Joel P Joseph Biological Sciences, Health, Medicine, News

Using viruses to kill Tuberculosis bacteria

This article was first published in Research Matters. Read the article, as it appeared on researchmatters.in, here.

Viruses are infamous for the infectious diseases they cause in different organisms — the year 2020 has proved it for us to see. But, a virus that causes an infection in one organism could be harmless in another. The Nipah virus, for example, is harmless in bats but causes a deadly disease in humans. Likewise, there are a group of viruses called bacteriophages that infect and kill bacteria but are harmless in humans. Within this group of viruses are myriad individuals, each one specific to certain bacteria.

In a recent study, researchers from the Indian Institute of Science (IISc), Bengaluru, have found that a cocktail of bacteriophages could kill Mycobacterium tuberculosis – the bacteria that causes Tuberculosis (TB), and its cousin Mycobacterium smegmatis­. The study was led by Rachit Agarwal, Assistant Professor at the Centre for BioSystems Science and Engineering, IISc, and the findings were published in the journal Frontiers in Microbiology.

Tuberculosis (TB) is one of the top 10 causes of death worldwide. It affected 10 million people and killed 1.4 million of them last year. India has the highest burden of TB worldwide, with nearly 4.5 lakh deathsreported in 2018. When M. tuberculosis infects a person, their immune system launches an attack against it. A group of immune cells, called macrophages, engulf the bacteria to form a packet inside the cell containing the bacteria with a slightly acidic environment. Typically, this packet would fuse with another component inside the cell, called the lysosome, which would make the environment more acidic and thereby kill the bacteria.

However, M. tuberculosis and its relatives have a smart way of escaping this process. They not only block this process of creating a more acidic environment, but they also thrive in an acidic environment and in low-oxygen conditions where other cells would die! They switch to a state in which they do not multiply fast, but grow slowly, residing inside these acidic compartments made by the body’s immune system.

Doctors treat tuberculosis with a combination of drugs that includes antibiotics. Over the years, the indiscriminate use of antibiotics has led the bacteria to develop resistance to these drugs, resulting in antibiotic-resistant tuberculosis infection. India also has the highest burden of such infections.

“The main motivation behind our study was the fact that antibiotic-resistance has been on the rise and is predicted to be a major global health crisis soon,” says Yeswanth C Kalapala, the lead author of the study.

In recent years, researchers have explored the use of bacteriophages against tuberculosis bacteria to curb their growth and kill them. The current study is no different. The researchers have studied how bacteriophages work against Mycobacterium in various disease-mimicking environments.

“We found that these bacteriophages were effective against Mycobacterium in various disease-mimicking conditions like acidic environment, low oxygen concentration and nutrient starvation,” says Rachit.

The researchers first studied the effect of single bacteriophage on the growth of Mycobacterium and later used a mixture of them — five different bacteriophages against M. smegmatis, and three against M. tuberculosis — in their lab.

“The bacteria develop some tolerance against individual phages over time, but a cocktail of phages inhibit the growth of the bacteria for a longer time and delay the development of tolerance to phages,” explains Pallavi R Sharma, one of the authors of the study.

The researchers found that the cocktail was effective in acidic environments, low-oxygen and low-nutrition conditions — all of which are present in cells infected with tuberculosis. It was also working against slow-growing bacteria. They then used the cocktail in combination with rifampicin, an antibiotic conventionally used to treat TB, on lab-grown bacteria. They found that the combination had a synergistic effect in reducing the growth when compared to the using either one separately.

As TB cases caused by antibiotic-resistant bacteria are on the rise, the authors also looked into the effect of the phage cocktail on an antibiotic-resistant strain of M. smegmatis. M. smegmatis generally do not cause a disease, but behave similar to other Mycobacteria. This allows researchers to use this bacteria in laboratory conditions where safety requirements are lesser than those for the use of M. tuberculosis, while giving them an idea of how M. tuberculosis might behave in similar conditions. Besides, M. smegmatis reproduce faster than M. tuberculosis. So, the authors used the antibiotic resistant M. smegmatis as a model to study how other antibiotic resistant Mycobacteria react to phage cocktails.

“We found that the five-phage cocktail was effective in infecting and killing antibiotic-resistant M. smegmatis. We also saw that the phage cocktail complemented rifampicin and eliminated the bacteria that were resistant to it,” says Yeswanth.

Following these interesting observations, the researchers are planning to study the effect of these phage cocktails on Mycobacterium tuberculosis growing inside human cells cultured in the lab and animal models like mice.

“We wish to see how this therapy can be used in animals and later translated to humans to treat TB, particularly in the case of drug-resistant TB,” signs off Rachit.

Joel P Joseph COVID Warriors, COVID-19, Health, Medicine

COVID-19: A day in the life of a healthcare worker

India has seen a steady increase in the number of reported COVID-19 cases in the last two months. While the country languishes under the weight of the pandemic, our healthcare workers are giving their all to the fight against the pandemic. Here is a story of a healthcare worker who treats COVID patients.

4.30 AM.

The alarm rings.

It’s time to wake up, do the domestic chores, get ready, and report to work.

“God, I hope I don’t get exposed [to the virus] today,” she thinks to herself as she gets ready to go to the frontline – to the war, as some would call it. The war that is fought using medical science, complemented with compassion, care, and love.

Susan Thomas is a staff nurse working in the Intensive Care Unit (ICU) designated for COVID-19 patients in a private hospital in Bengaluru. Before the pandemic, her duty used to last 8 hours a day, six days a week. But things have been different since the end of March. She has been working for about 12-14 hours a day, five days a week.

On a typical day at work, Susan goes into the COVID ICU after she has put on the personal protective equipment (PPE). There, her predecessor updates her about the status of the patients and hands them over to her care.

“It’s a lot of pressure and it’s physically exhausting,” Susan says. “It’s more than just taking care of patients. There is also the paperwork that must be done. All this extra work takes up a lot of time, but we have to do it for the good of everyone. There is very little time to have food or even to take a break in between.”

She has to protect herself while treating the patient. Even the smallest mistake or negligence can get her infected. It’s quite an ordeal. The PPE makes the routine work also difficult. “I am soaked in sweat for the most part of the day. And things get worse when I have my periods,” Susan says. While on duty, she hums a tune or sings a chorus to keep herself calm and make the patient also feel better.

After the long day at work, all she just wants to do is to get home, take a shower and hit the bed with the hope that her patients get better. Although she tries not to think about her patients when she is going to sleep, it seems impossible sometimes. I tell myself, “Hey, stop thinking about your patient now!”

The ordeal of being in treating patients during a pandemic is not only physically exhausting but is also mentally taxing. Susan combats this challenge by making the best of the days when she is not working. She cooks, listens to music, prays, and catches up on the lost sleep, getting herself ready for another week of fighting the pandemic.

Joel P Joseph Medicine, Motivational, Women in Science

Christian Medical College: Ida Scudder’s legacy to the Vellore community

Dr Ida Sophia Scudder – the founder of Christian Medical College (CMC), Vellore – breathed her last sixty years ago on this day. But her life and legacy continue to inspire hundreds of thousands across the world. An American by origin, Dr Ida spent her lifetime uplifting the community in Vellore through her medical practice. Her work is never more relevant than now when we are facing a pandemic. In this article, I have attempted to highlight some of the contributions of Dr Ida Scudder,  and others, which continue through CMC, Vellore. 

Dr Ida S. Scudder. Picture Source: http://www.friendsofvellore.org
CMC Vellore campus. Picture Source: http://www.cmch-vellore.edu

It would be hard to believe that the town which once greeted medical officers, who tried to vaccinate people to contain the plague, with sticks and stones would later be the first in the country to be polio-free. The person whose life and legacy was mainly influential in bringing this change was a woman physician by name, Ida S. Scudder. Dr Ida Scudder and the professionals at the medical college she founded – Christian Medical College (CMC) – transformed the community in Vellore to what it is today.

CMC, Vellore, is renowned globally for its many achievements in the field of medicine. One of the major contributions of the medical college, through which the legacy of Aunt Ida continues, is its community service. From Dr Ida Scudder’s efforts in containing the plague outbreaks to Dr Paul W Brand’s accomplishments in rehabilitating lepers and Dr T Jacob John’s leadership in eradicating polio and containing HIV/AIDS, CMC’s services to public health have not only impacted Vellore and India but has also influenced the world.

It all began one night at Tindivanam, Tamil Nadu, when 20-year-old Ida Scudder encountered a life-changing incident. Three men – a Brahmin, an upper-caste Hindu, and a Muslim – approached Ida seeking help for their wives who were in labour. Ida explained that she had no medical training, but her father who was a missionary doctor could help them. But none of them would agree. In Ida’s words, the Brahmin drew himself up and said, “Your father come into my caste home and take care of my wife! She had better die than have anything like that happen.” The Muslim also responded with similar words saying, “She had better die than have a man come into the house.” Ida could not sleep that night. She wrote about this incident later, “Within the very touch of my hand were three young girls dying because there was no woman to help them.” She spent the night in anguish, torn between a great life in America and the need to serve the people in India. Ida had come to Tindivanam only to take her ailing mother back to the USA. Until that night, she wanted to enter Wellesley College and “continue in the happy free life of a young woman in America.”

The next day, Ida sent a servant to check what had happened to the three women only to hear that all of them had died the previous night. She shut herself in the room. After much thought and prayer, Ida told her parents that she wanted to go home and study medicine to come back and help such women in India.

In 1895, Ida entered the Women’s Medical College of Philadelphia. It was a time when women were not welcome as qualified surgeons and doctors. Three years later, when Cornell opened its doors for the first time for women students of medicine, Ida transferred there for better opportunities. As Mary Pauline Jeffrey writes in her biographical account of Ida Scudder, some students at Cornell often “did things to make women feel that they were foreign bodies.” Nobody would have imagined then that about 50 years later, Ida would be admitting male students to the Women’s Medical College she founded at Vellore!

On January 1, 1900, Dr Ida Scudder landed in India. She started running a clinic in a 12*8 feet room at her house. Meanwhile, she worked toward realizing the hospital for which she had received a donation of $10,000 while in the USA. In 1902, the 40-bedded Mary Taber Schell Memorial Hospital opened. Her vision was that women should have equal access to quality healthcare as men, regardless of their religious or socio-economic status. In 1909, Dr Ida established a school of nursing and in 1918 she established a medical college for women. The medical college was called Missionary Medical College for Women. In 1945, it was renamed as Christian Medical College and in 1947 CMC opened its doors to male students.

The tiny clinic and the hospital thus grew to be the medical college that would have many firsts to its credit. Dr Ida was deeply connected with the community she lived in – a legacy that the medical college would become renowned for. This was never more relevant to us than now. In 1903, when the plague hit Vellore, as many as 17 people were dying every day. In 1904, the total number of cases in India had reached 1,100,000 before preventive measures showed any sign of success. At that time, along with the municipal commissioner, Dr Ida “sallied forth to grapple with the deadly epidemic. Into the homes of the community in Vellore these two went, enforcing sanitary measures and administering prophylactic inoculations.”

Half a century from then, Dr Paul Brand carried that torch making another mark in the community in Vellore. Realizing his life’s calling at CMC, Dr Paul established the New Life Center at Vellore to rehabilitate lepers and dispel the stigma that prevailed even among medical professionals. Dr Paul also performed the world’s first reconstructive surgery on leprosy patients at CMC, Vellore.

Paul Brand
From Left to Right: Drs Brand, Scudder, Balfour, Chandy. Picture Source: http://www.cmch-vellore.edu

A couple of decades later, Vellore became the first town to eradicate polio. An alumnus of CMC, Dr T. Jacob John led the initiative of making Vellore polio-free and later headed the national efforts in eradicating polio. In his own words in conversation with the journal Current Science, “Globally, Vellore was the centre conducting such basic and problem-solving research on polio from the mid-1960s.” Dr Jacob John headed the virology services at CMC from 1967-1995. During this time, he also played a key role in India’s efforts to contain HIV/AIDS.

Dr Ida Scudder’s legacy continues through the work of CMC. The medical college has produced some of the best doctors, surgeons and scientists in the country, who have been recognized for their work.  Of special note in the context of public health, epidemiology and community medicine are experts like Dr Gagandeep Kang, Dr T. Jacob John, Dr Jayaprakash Muliyil and others.

At this time, when the country is faced with an epidemic, Dr Ida Scudder’s legacy serves as a reminder of what empathy, compassion and boldness can help one achieve. It is her legacy that we need now – of providing quality and compassionate healthcare for all sections of society.

Sources:

*All the quotations with no explicit mention of the source are from the book: Ida S. Scudder of Vellore (2014). By Mary Pauline Jefferey.

https://www.vellorecmc.org/who-we-are/history/

https://friendsofvellore.org/about/history-of-cmc/

https://www.theguardian.com/news/2003/aug/27/guardianobituaries.health

https://leprosyhistory.org/database/person31

https://www.currentscience.ac.in/Volumes/114/03/0436.pdf

 

Joel P Joseph Biological Sciences, Health and Lifestyle, Medicine

TB talk: an interview on World Tuberculosis Day

On World Tuberculosis Day (March 24, 2020), I interviewed Priyadharshini M V, project assistant in Mycobacterium Diseases in Animal Network (MyDAN) lab at Tamil Nadu Veterinary and Animal Sciences University (TANUVAS), Chennai. She holds an M.Tech in Biotechnology and worked as a medical geneticist in Centre for Medical Genetics, Chennai, prior to her work at TANUVAS. In this interview, she elaborates on TB, the challenges and mitigation strategies in India, and how the general public can contribute to the fight to eradicate TB. 

New Doc 2020-03-25 13.18.53 (1)   h5FQsSizWwiUWBXMmhYkD8-320-80

Left: Priyadharshini M V. Right: A depiction of Mycobacterium tuberculosis in a patient’s lung. Picture retrieved from livescience.com

Could you please tell a little bit about TB and how badly India is affected by TB?

TB is an airborne disease caused by the bacterium Mycobacterium tuberculosis (Mtb). It is the leading cause of death from an infectious disease worldwide and claims about 3 lives every minute. TB is curable and preventable. The bacteria usually attack the lungs (pulmonary TB) but can also attack other parts of the body like the kidney, spine, and brain.

Not everyone infected with TB bacteria becomes sick. So, there are two TB-related conditions: latent TB infection (LTBI) and TB disease (active TB). Many people who have latent TB infection never develop TB disease, but there are a few exceptions. If it is not treated properly, TB can be fatal. There are also the multidrug-resistant (MDR) and extensively drug-resistant (XDR) forms of TB that occur, but they are still rare.

India accounts for about a quarter of the global TB burden. Worldwide, India is the country with the highest burden of TB – both TB and MDR TB. There are an estimated 79,000 multi-drug resistant TB patients among the notified cases of pulmonary TB each year. India is also the country with the second-highest number (after South Africa) of estimated HIV associated TB cases.

How does a person get infected with TB? What are the symptoms of the disease?

The TB bacteria are introduced into the air when a person with TB disease of the lungs or throat coughs, sneezes, speaks, or sings. People nearby may breathe in these bacteria and become infected.

TB disease in the lungs may cause symptoms like a bad cough that lasts 3 weeks or longer, pain in the chest, coughing up blood or sputum (phlegm from deep inside the lungs). There are also other symptoms like weakness or fatigue, weight loss, loss of appetite, chills, fever, sweating at night.

Could you describe some measures taken by the government to curb this disease?

The Government of India aims to eliminate TB by 2025. This was announced by Shri J P Nadda, Union Minister of Health and Family Welfare, in March 2017. For this, a lot of things set out in the National Strategic Plan 2017 – 2025 needs to be done.

According to the World Health Organisation (WHO), the elimination of TB means that there should be less than one case of TB for a population of one million people. TB treatment and care in India is provided in the public sector by the government’s Revised National TB Control Programme (RNTCP), which is responsible for implementing the government’s five-year plans to combat TB. India’s remarkable achievements in TB control in the last ten years include testing more than 80 million people, detecting and treating 15 million TB patients, and saving millions of lives as a result of the efforts of the RNTCP.

What are some of the plans in this new strategy of the government?

The financial resources for TB control for 2017-2025 are doubled, the diagnostic tool CB-NAAT is to be rolled out across the country, and the two drugs Bedaquiline and Delamanid are also scheduled for a broader rollout. First and second-line drug susceptibility testing is in use or at least on the agenda. Also, patients with TB are tested for HIV and patients with HIV are tested for TB. Drug treatment is moving from intermittent therapy to daily fixed-dose combinations.

 

Why, in your opinion, has the battle against TB in India been difficult?

India’s progress against the disease has not been consistent. As per WHO reports, it has been a persisting problem in developed countries. People infected with HIV are 19 times more likely to develop active TB. The risk of active TB is also greater in people suffering from conditions that impair their immune system. Malnourished or undernourished people are 3 times more likely to contract TB when compared to the others. So, it’s pretty obvious that India, being a third world country with two-third of its population in poverty and having the third-largest population suffering from AIDS, has been struggling to combat and eradicate TB. Shortage of resources and research is another big limitation.

How can the general public contribute to the fight against TB?

There are two important things one can do to contribute to the fight against TB: One is to create awareness about the disease and the other is to get the people who fall in the high-risk group to test for TB. People with HIV infection, people who were infected with TB bacteria in the last 2 years, babies, young children, people who inject illegal drugs, people who are sick with other diseases that weaken the immune system, people who were not treated correctly for TB in the past, and the elderly are at high risk of developing TB disease.

People who anticipate repeated or prolonged exposure or an extended stay over a period of the year may undergo annual testing. Additional preventive measures could include using personal respiratory protective devices. Tuberculosis germs don’t thrive on surfaces. You can’t get the disease from shaking hands with someone who has it or by sharing their food or drink.

If one has latent TB, he/she must take all of his/her medication, so he/she doesn’t develop active TB, which is contagious. People with active TB must limit their contact with other people at work, school, or home. They must cover their mouth when they laugh, sneeze, or cough and wear a surgical mask when they’re around other people during the first weeks of treatment.

People travelling to a place where TB is common must avoid getting close to or spending a lot of time in crowded places with people who have TB. Children in countries where TB is common should get the BCG vaccine.

Joel P Joseph Health and Lifestyle, Medicine

Be empathetic: A message on World Down Syndrome Day

March 21, 2020: On World Down Syndrome Day, I interviewed Suruthi Abirami, a genetic counsellor, about her personal experience in helping people who are fighting this disorder. Suruthi Abirami currently works as a genetic counsellor and geneticist at Anderson Diagnostics and Labs, Chennai. She completed her postgraduate diploma in medical and genetic counselling from Kamineni Hospitals Pvt. Ltd. and her M.Tech in Genetic Engineering from SRM Institute of Science & Technology. She is a Level 1 Genetic Counsellor certified by the Board of Genetic Counselling, India.

Suruthi

Suruthi Abirami at Kamineni Hospitals Pvt. Ltd., Hyderabad

Could you please briefly share your journey as a genetic counsellor so far?

My journey of helping families with genetic disorders make informed decisions has been incredible. In a country like India, the challenging part for me is to consider the psycho-social and religious aspects of the families while making decisions. I counsel roughly about 20 patients in a week. I also provide scientific support for clinicians around the country. I help them understand the situation and offer the best genetic testing for the patient.

How has your experience with Down syndrome patients been?

With many new technologies that are available these days, most of the pregnant women around the country are offered prenatal screening for Down Syndrome and other genetic conditions. That means pregnant women are screened to see if the baby they are expecting has a risk of having Down syndrome. If the screening shows a high risk, a confirmatory test is done, and the couple is counselled to make informed decisions. So, most of my counselling in case of Down syndrome is for couples with a high risk of having a child with Down syndrome. I mostly counsel them before the child is born. When the confirmatory test is positive, I counsel them about the condition, prognosis and management.

From your experience, how prevalent is this rare disease in India?

Down syndrome is no longer a rare disease in India. India lacks statistical data, but I think about 1 in 750 to 1000 births in India may have Down syndrome. By educating the public about the prenatal screening for Down syndrome, the situation can be improved.

What kind of problems do these Down syndrome patients deal with?

The main problem is social stigma and acceptance. The average life expectancy of individuals with Down syndrome is 60 years. But they need constant medical care because they suffer from different levels of intellectual disability, cardiac issues, thyroid dysfunction, poor muscle tone and low immune system.

What message would you like to share with the community on World Down Syndrome Day?

As we celebrate people with Down Syndrome today, I urge everyone to be empathetic. Show love and acceptance for people with Down syndrome and other genetic disorders. They deserve a life just like all of us and recognizing them as one among us means a lot to this community. At the end of the day, that is what every single person in this world with a rare disease or genetic disorder wants.

Joel P Joseph Biological Sciences, Health and Lifestyle, Medicine

COVID-19: key terms you should know

2019 nCOV cryoEM structure

Side and top views of the structure of a protein – S protein – of 2019-nCoV.          Retrieved from the paper by Wrapp and others published in the journal Science.

With new COVID-19 cases being reported in India, there has been a deluge of information – news stories, articles and awareness campaigns – around it. Containment, social distancing, transmission, flattening the curve, epidemic, and pandemic are some terms that you will now find in most articles. In this short post, I try to explain some of these terms.

COVID-19, SARS-CoV-2, 2019-nCOV: COVID-19 (Coronavirus Disease) is an infectious disease caused by the most recently discovered coronavirus. Coronaviruses are a family of viruses that have RNA as their genetic material. Other viruses of this family include MERS (Middle East Respiratory Syndrome coronavirus), SARS (Severe Acute Respiratory Syndrome coronavirus) and viruses that cause common cold (E.g. Rhinoviruses). The new coronavirus was initially called 2019-nCOV (2019 novel coronavirus) when it was first identified in China. The virus is now named SARS-CoV-2 (Severe Acute Respiratory Syndrome coronavirus 2). WHO announced the name of the new coronavirus disease as COVID-19 on February 11, 2020.

Endemic: A disease, or an infectious agent that causes it, is called an endemic when it is usually present in or is restricted to a community in a certain geographical area. For example, Kyasanur Forest Disease (KFD), commonly known as monkey fever is a viral disease endemic to South India. This is a disease seen in specific areas in South India. KFD is an endemic prevalent in Shimoga district of Karnataka.

Epidemic: When the number of disease cases is in excess than the normally expected numbers, then the disease is called an epidemic. The numbers of normally expected cases are defined specifically for each case. When the number or density of susceptible cases exceed a threshold (called an epidemic threshold), the event is defined as an epidemic.

Outbreak: When the disease cases that occur are more than what is normally expected, it is called an outbreak. For example, there were two outbreaks of Nipah in Kerala (2018 and 2019). Although epidemic and outbreak have overlapping definitions, an outbreak can be seen as the process of occurrence of an epidemic.

Pandemic: When a disease epidemic spreads across a continent or worldwide, it is called a pandemic. WHO characterized COVID-19 as a pandemic on March 11, 2020.

Infected person: A person who has the infectious agent, which causes the disease, in his body.

Incubation period: This is the time in which the infectious agent (say, a virus) is present in the host (an infected person), but the person has no symptoms. The incubation period for COVID-19 is 14 days or less. According to a study, the average incubation time for COVID-19 is 5.5 days. Less than 2.5% of the cases develop symptoms in 2.2 days and 97.5% of the cases develop symptoms in 11.5 days. Only 1 in 10,000 cases developed symptoms after 14 days.

Convalescent period: This is the time when an infected person recovers from the illness.

Transmission: The way in which a disease spreads from one person to another is called transmission. If the disease is transmitted from an infected person to a healthy person, it is called contact transmission. Contact transmission can be direct – when there is physical contact between the infected person and the healthy person, or indirect – where the infectious agent spreads by indirect means without direct physical contact. Indirect transmission can include droplet transmission or transmission by fomites.

Droplet Transmission: When an infectious agent (say, a virus) is transmitted through respiratory droplets that are propelled into the air by sneezing or coughing, it is called droplet transmission. When an infected person coughs or sneezes, droplets of moisture of different sizes contaminated with infectious agents are propelled out in the air. When these droplets contact the eyes, nose or mouth of a healthy person, he/she can get infected. Droplets are usually heavier and settle down to the ground quickly because of gravity. These droplets can be propelled to about 1 metre depending on the size of the particle and the force with which it is expelled.

Aerosol Transmission: When an infectious agent (say, a virus) is transmitted through aerosols (suspension of fine particles in the air) propelled into the air by sneezing or coughing, it is called aerosol transmission. When an infected person coughs or sneezes, aerosols of moisture of different sizes contaminated with infectious agents are propelled out in the air. Aerosols are lighter and can remain in the air for sometime before it falls. They can be propelled up to 3 metres depending on the size of the particle and the force with which it is expelled. SARS-CoV-2 is reported to be stable in aerosols for 3 hours.

Transmission by Fomites: Fomites are non-living objects that can be contaminated with infectious agents and can transmit the disease. These include water, plastics, metals – doorknobs, keyboards, phones, handrails etc. If an infected person sneezes or coughs and the droplets fall on fomites, the infectious agents can remain active on fomites for hours or days. When a healthy person touches an infected surface and then touches his/her nose, eyes or mouth, the infectious agent can get inside the body. A recent study has shown that SARS-CoV-2 can be viable for 3 hours in aerosols, and up to 3 days on stainless steel, copper and cardboard surfaces.

Local Transmission: When the source of infection is present with a locality, there is local transmission of the disease. That means if a person in Bangalore gets infected by someone who is in Bangalore, then there is a local transmission. This is referred to as stage II of the epidemic.

Community Transmission: When one cannot relate confirmed cases by chains of transmission (i.e., when one cannot trace the source of infection of all the different people in the chain) for a large number of cases, then it is called community transmission. In other words, if a person who has not come in contact with anyone known to be infected and has not travelled to any country when the virus is spreading tests positive, then there is community transmission. This is referred to as stage III of the epidemic.

Social distancing: It is the practice of maintaining more than the usual physical distance from other people. The purpose is to stop or slow down the spread of a disease that can be transmitted by physical contact, droplets, or fomites. The more distance you maintain from people, the lesser the risk of getting the disease.  

Flattening the curve:  This is a term used to indicate preventing a sharp peak of infections. During an epidemic, the disease spreads quickly as infected people come in contact with healthy people, who in turn come in contact with more people. Let us say there is one infected person (the person may or may not have developed symptoms). He/She hangs out with 3-4 friends. There is a possibility that these 3-4 people are now infected. These people now meet with more people, who in turn meet other people. Suddenly there is a sharp increase in the number of cases when all of these people develop symptoms within a few days. This overwhelms the healthcare system. If people practise social distancing, the chances of infection are lesser and, therefore, the sharp peak can be flattened as lesser cases are present in a given time. This can reduce the burden on the healthcare system.

Quarantine: The process of isolating people who have been exposed to an infection that can spread. The aim of quarantining is to contain – prevent the further spread of – the disease. Quarantine for 14 days is recommended for suspected COVID-19 cases.

Herd immunity: This is indirect protection for susceptible people in a community. In an outbreak, if a large proportion has become immune to the infection, they indirectly protect people who are not immune to the infection by disrupting the spread. Consider the situation with COVID-19. Let us say healthy people get infected. They become sick, isolate themselves (especially from people who are at higher risk of death by infection because of other health conditions) and eventually recover. When the number of recovered people increases in a population, they indirectly protect those who have not been infected as the chain can now be broken quickly.

Covidiot (informal use): This term is used to refer to a person who ignores the warnings regarding public health or safety and hoards goods denying them from their neighbours during the COVID-19 pandemic.

Sources:

https://www.cdc.gov/csels/dsepd/ss1978/glossary.html

https://www.who.int/emergencies/diseases/novel-coronavirus-2019

 

Joel P Joseph Biological Sciences, Medicine, News

Scientists identify a compound that protects neurons from degeneration

460711949-56a793d25f9b58b7d0ebda5c     neuron

Scientists from the Bengaluru-based institution Jawaharlal Nehru Center for Advanced Scientific Research (JNCASR), with the help of National Institute of Mental Health and Allied Sciences (NIMHANS) and Center for Cellular and Molecular Platforms (C-CAMP), have identified a molecule that could clear toxic aggregates in the brain and reduce the loss of neurons (neurodegeneration). The study was led by Dr Ravi Manjithaya, Associate Professor, Autophagy laboratory, Molecular Biology and Genetics Unit, and Associate Faculty of Neuroscience, JNCASR. The findings were recently published by the Lancet journal EBioMedicine.

Parkinson’s disease is a neurodegenerative disease that affects 10 million people worldwide. In Parkinson’s disease, misfolded proteins form clumps in a set of neurons in the brain – the neurons that release dopamine (dopaminergic neurons). These aggregates, known as Lewy bodies, majorly constitute a misfolded protein called α-synuclein and result in the loss of dopaminergic neurons. Loss of dopaminergic neurons affects the movement and cognition of a person. The person is unable to walk properly, has shaky hands and legs, and becomes forgetful, drastically affecting his/her quality of life.

Several scientists across the globe have tried to develop drugs that reverse this situation but have failed. In this study, the team of researchers identified a chemical compound that blocks a protein (c-abl kinase), thereby clearing the toxic aggregates formed. The team had to screen numerous small molecules before pinning down on the small molecule, PD180970.

The team overexpressed (forced synthesis beyond natural limit in the cell) α-synuclein in yeast cells, making it toxic for the cells and killing them. This model could mimic how α-synuclein aggregates kill neurons and the researchers tested the small molecules on this. “We screened a small molecule library and identified those that rescued growth of yeast cells expressing the Parkinson’s disease-associated protein, α-synuclein,” Dr Manjithaya said. “Later we narrowed down to molecules that were rescuing the growth defect in an autophagy-dependent manner.”

The team found that PD180970 could inhibit c-abl kinase and induce autophagy to reduce the toxicity in neurons caused by the aggregates. This was evidenced by their studies on neuronal cell lines and in mouse midbrain. In addition to clearing aggregates, preventing the inflammation of neurons is important to stop neurodegeneration. “A small molecule that induces autophagy to clear the aggregates and also has anti-inflammatory property would be more potent in curbing neurodegeneration,” Dr Manjithaya said. “This is how we think PD180970 works,” he added.

The collaborations with Dr Phalguni Alladi, Senior Scientific Officer, NIMHANS, Dr James Clement Chelliah, Neuroscience Unit, JNCASR, and Dr Taslimarif Saiyed, CEO and Director, C-CAMP, were vital in this aspect. “While my lab focuses on the autophagy aspects, my collaborator Phalguni Alladi at NIMHANS mentioned about the impact of neuroinflammation. To this end, we collaborated with Taslim’s lab at C-CAMP to test if any of our molecules had anti-inflammatory properties.” Dr Manjithaya said. “PD180970 was the most effective among the ones they tested.” PD180970 prevented neuroinflammation by inhibiting cytokines like IL-6 (interleukin-6) and MCP-1 (monocyte chemoattractant protein-1), which facilitate inflammation.

Dr Manjithaya is highly appreciative of collaborations in science. “As a young researcher, having collaborations is looked down upon in our country although it is the norm and is encouraged in the western world,” he said. “Good collaborations bring in various aspects that make a study complete. Apart from their unique expertise and direction, there is further confirmation of the work, and more importantly different – sometimes contrasting – views. That makes you think more critically about your data and gives a fresh perspective. This study is a culmination of efforts from four labs across three institutions.”

In mice where the dopaminergic neurons were degenerated by injecting a chemical called MPTP. Treatment with PD180970 along with MPTP injection improved the condition. This was supported by evidence from the changes at a molecular level in the brain and the behavioural changes that occurred in the mice.

That’s not all. The lab is working with Vipragen Bioscience to patent the molecule and take it forward to the next stage in drug development.

Read the full paper here

Pictures from verywellmind.com andeinstein.yu.edu

Joel P Joseph Biological Sciences, Interviews, Medicine

A viral conversation: Interview with Dr G Arun Kumar

Dr G. Arun Kumar, currently heading Manipal Institute of Virology (MIV) under Manipal Academy of Higher Education (MAHE), is a renowned Indian microbiologist and virologist. He also heads the Regional Reference Laboratory for Influenza viruses established by Ministry of Health and Family Welfare, Government of India at Manipal and the ICMR Virology Network Laboratory (Grade-1) at Manipal. He is the pioneering scientist, who established the virology facility in Manipal with the support of the University and the Government. His research interests include viral diseases, epidemiology and diagnostic virology and public health response during infectious disease outbreaks. He led the team that was instrumental in containing the first Nipah Virus outbreak in South India. He is an expert member of several national and international committees pertinent to public health. 

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Dr G. Arun Kumar at Manipal Institute of Virology

How did you come to join Manipal Academy of Higher Education and how was the virology facility set up there?

I came to Manipal in 1994 to pursue MSc in Medical Microbiology after my BSc in Medical Laboratory Technology from Trivandrum Medical College. It was within a year since Manipal had become a deemed university. As soon as I finished MSc, I received the CSIR-JRF fellowship and went to the All India Institute of Medical Sciences (AIIMS), Delhi, to pursue my PhD in Virology.

About six months into AIIMS, as I was preparing to register for PhD there, my Professor from Manipal, Dr P G Shivananda MD, PhD., wrote to me asking me to join them. It was a difficult decision to take as Manipal did not have a virology lab at that time. The risk-benefit analysis showed that it was risky to move to Manipal. But my professor was insistent and promised me to provide a small facility for virology. I also discussed these things with my guide Dr Pradeep Seth, MD at AIIMS, New Delhi, and he also suggested taking up Manipal’s offer. I then thought that moving to Manipal was a challenge I had to take up – to initiate something that would have a lasting impact not only on me but also on the institution.

So, I joined Manipal as a lecturer in Nov 1997. I wrote a proposal to Prof. M. S. Valliathan, the then Vice-Chancellor of MAHE, through my professor, Dr P G Shivananda, to establish a virology laboratory. After a year, INR 500,000 was granted to set up a virology facility. That is how the virology lab was set up in Manipal and I came to be associated with it.

How did this facility grow to be an internationally renowned institute?

In May 1999, we set up a small lab with viral serology, tissue culture and virus isolation facility and started working on some clinically relevant viruses. We started the work with Respiratory Syncytial Virus (RSV) as I had worked on it in AIIMS and was familiar with it. I also started my PhD on RSV and completed it in 2002. By then we were actively working on 4 to 5 viruses and were providing diagnostics for it. This was also the time when we started attending conferences and people started noticing our work.

In 2003, there was a huge outbreak of SARS in Hong Kong. Government of India started looking at developing the capacity to detect and fight this virus. A review committee emphasized the requirement for more virology labs in India. The government also wanted to prepare the country for Avian Influenza (bird flu) Virus. Fortunately for us, without our knowledge, our facility was identified as a potential lab to be supported to work on these programs.

In 2007, we got a letter from the Indian Council of Medical Research (ICMR) asking if we were willing to develop the lab to a state-level virus diagnostic and research laboratory (VRDL). Following an expert site visit and a detailed project proposal review in 2010, they sanctioned a grant of INR 5 crore for a period of five years.  Meanwhile National Centre for Diseases Control (NCDC), Delhi had included our lab under the network of regional influenza laboratories.  This enabled our facility to be notified as a reference laboratory for influenza A H1N1 when the pandemic influenza arrived in India in 2009. The ICMR- VRDL facility was established in March 2010. Subsequently, realizing the potential of the lab, MAHE elevated it as a University department – Manipal Centre for Viral Research (MCVR). Now I had to report directly to the Pro-Vice-Chancellor of the university. This removed many hurdles and facilitated a faster decision-making process. We also moved into a new building with the support of the university. In this way, we grew in close association with the State and Central Health Services in India in the area of disease surveillance

In 2013, we had another quantum leap when we received a foreign grant from the Centre for Disease Control (CDC), USA as part of the global health security agenda (GHSA). We were awarded a sum of USD 250,000 to study emerging pathogens in the human-animal interface. We started the study in Shimoga, Karnataka. It progressed well and we received an upgrade of the award in 2015 to carry out the study in ten states in India. With that our funding had increased and our capacity grew tremendously. This enabled us to become a centre for excellence in disease surveillance and outbreak investigations.

In this way, we grew with the support of the university and the Government of India. We received several grants from the government and the university provided us with the infrastructural support. Manipal provided enormous support, space and freedom to grow and implement some of the dreams I had. The support has continued and now we have been elevated as independent institute – Manipal Institute of Virology (MIV) – under the university with higher containment labs and facilities.

MCVR (now MIV) did an excellent job in checking the Nipah virus outbreak. How did you go about detecting this rare virus?

Since 2009, we have been working very closely with Kerala on the detection of Pandemic Influenza. Besides the Influenza virus, we would also run diagnostic tests for other viruses in many cases. Gradually, many doctors of Kerala gained confidence in our viral detection tests and we developed a close relationship with the doctors. Baby Memorial Hospital at Calicut was one of the hospitals we had been closely working with.

In May 2018, a patient with symptoms of Encephalitis came to Dr Anoop Kumar at Baby Memorial Hospital. His brother had died with a similar illness 12 days earlier and two others in his family were also sick. This cluster of brain fever in a family raised an alarm. There were two possibilities viz., (i) Serial Poisoning (ii) An infection. When Dr Anoop called me around lunchtime on May 17, 2018, and explained the case, I sensed that it was a serious case. I directed him to collect multiple clinical samples and asked him to send it across quickly by hand. In a usual case, the samples are collected through a nodal officer at the district and are sent as a batch by train either daily or on alternate days.

In our primary investigation of this sample, in addition to the test for common Encephalitis agents like Herpes Simplex Virus and Japanese Encephalitis Virus, we tested for Nipah Virus as well. In the usual case of Encephalitis from Kerala of Karnataka, we would never consider testing for Nipah in the first set. But we considered it because of our understanding of Nipah epidemiology and knew that Nipah presents as a family cluster of encephalitis. Nipah virus testing was not new for us. In our fever study program in Assam and Tripura, we had tested samples for Nipah in the border areas close to Bangladesh (Bangladesh has been reporting Nipah cases every year since 2001) but didn’t detect any. That is why we considered it in our primary investigation and it turned out that the patient was positive for Nipah. But since this was from a different region, we were sceptical. We wanted to be sure. So we tested for about 30 other agents and by evening we were sure that it was Nipah only.

How did you tackle the situation when you realized that you were dealing with this deadly virus? What were the measures you took to rise to this public health challenge?

By the evening of May 17, 2018, we knew that we were dealing with Nipah. But you cannot announce it right away as it would have implications on national and international mobility. We also had to be absolutely sure of the agent. But the information had to be conveyed quickly to contain the virus and avoid transmission.

So immediately we sent the samples to National Institute of Virology (NIV), Pune, for a reconfirmation. In the meantime, we alerted the central and the state government authorities about the virus without naming it and urged the hospitals to isolate people who had come in contact with the patient.

Kerala responded to this situation in a very positive way. The health department instructed the hospitals about isolation procedures and patient care. The healthcare workers were pro-active, and the public also responded well.

The Hon. Health Minister of Kerala Smt. KK Shailaja teacher asked me to join them on the field as very little was known about this outbreak and had to be investigated. When we got there, we realized that there were several undiagnosed deaths in the medical college that week. Fortunately, the samples were preserved for few cases at least and they turned out to be positive for Nipah.

But these cases had no obvious connection to the first patient or the family. This was frightening. By this time the public and the government were growing restless and wanted to know what was happening. If these cases were not linked to the first cluster, we would have to consider the case of a biothreat. But Nipah is a difficult agent and is usually not used as a bioweapon. We launched a thorough epidemiological and virological investigation and traced those who had come in contact with the initial patients, isolated them and put them under surveillance. The health department of Kerala had already started isolation procedures on the night on May 18.

We then went into a detailed investigation of the first case, twelve days before the reported death. The patient was hospitalized in the Taluk hospital for one day and in the Medical College Hospital for another day. The Taluk hospital had already been evacuated, but the staff recreated the scene of the original patient in the ward. He had cough, vomiting, and irritability. His father and brother had attended to him and there were some deaths from the same ward because of human to human transmission. Nine cases were thus linked to this hospital.

When we tried to trace the other cases, we found an intriguing association with the radiology corridor of the Calicut medical college. Investigations revealed that the index case when admitted to Calicut medical college was subjected to a CT scanning on 5 May and most of the cases had exposure to index case that day. The index case was moved around the CT scan room and in the corridor for about four hours since it was difficult to get his scan due to his altered sensorium and irritability. CCTV footages helped trace this exposure.  Once this link was established, we were relieved. Health department identified all contacts of these people and isolated all symptomatic cases and the situation came under control.

After this, the health department called for a meeting with News Editors and discussed the situation. We made them aware that Nipah is transmitted by droplets, where the person had to be within one-meter vicinity of the patient for it to be transmitted and not by aerosol (Airborne). At the start of the meeting, about 60% were wearing masks and at the end of it, no one was wearing a mask as the mask was required only for persons in close contact with the patient. This communication helped a lot to clear the public fear.

In retrospect, how do you view this achievement of Nipah intervention and what do you think about it?

Looking back, I think there were some critical junctures where important decisions had to be taken. The district administration was very supportive and was with the health team all the time. There was very good participation and intervention by the state and central health services. Hon. Health minister of Kerala Smt. KK Shailaja Teacher, The Additional Chief Secretary of Health department Sri. Rajeev Sadanandan and the Director of Health Services Dr RL Sarita has provided exceptional leadership. The Nipah emergency operation room at Calicut worked flawlessly in coordinating the response. It was a very good model and I am afraid if it can be replicated in other places.

Recently, Manipal Institute of Virology was added as a centre of Excellence within Global Virus Network (GVN). Could you please tell me a little bit about GVN and how you view this addition?

Global Virus Network (GVN) was founded by Robert Gallo, who won the second Lasker Award for the discovery of HIV, in conjunction with William Hall of University College London and Reinhard Kurth of the Robert Koch Institute. It is a Non-Government network that brings virologists and institutes together in a collaborative effort to fight viral infections.

The idea of the network is to develop expertise through centres for excellence and to exchange it among them to act quickly during an outbreak. The aims of the network include collaboration among virus scholars, expansion of virologist training programs, and evidence-based policy advocacy. The network also collaborates with WHO and gives expert opinion helping in framing evidence-driven policies.

I think our addition to the GVN will help us in building our capacity, be instrumental in framing evidence-based policies and to work on one health – a concept that tells that the health of people is connected to the health of animals and the environment, which is nascent in India. This collaboration is going to help us in the study of these aspects.

What is your vision for MIV for the next 10 years?

As we are transitioning from a centre to an Institute we are redefining our vision and goals. In the next ten years, we envisage transforming MIV to the most preferred place for infectious diseases researchers especially in the area of emerging and re-emerging diseases.  We will enable and nurture basic, translational and public health virology research which is designed to contribute to achieving the sustainable developmental goals.

As a person who has been instrumental in building a centre of excellence in research, what is your advice for other academicians treading the path?

Three things are important to build a department or institution: (i) Your team: You need people who stay with you and understand your vision and philosophy (ii) An enabling leadership and environment (iii) Liaison with government systems and stakeholders.

It is also important that you grow in a niche area. For example, we specialized in disease surveillance, outbreak detection and pathogen detection, which requires quick mobilisation the team in the field.

However, it is important to periodically identify the strengths, weaknesses, opportunities and threats and strategize to reinvigorate the growth rate.

Joel P Joseph Biological Sciences, Medicine, Motivational

The Nobel winners, 2019: Physician-scientists who discovered how cells adapt to changing oxygen levels

The Nobel Prize in Physiology or Medicine, 2019 was awarded to Gregg L. Semenza, William G. Kaelin Jr. and Peter J. Ratcliffe and for their work on how cells sense and adapt to oxygen availability. Their research elucidated the genetic mechanisms through which cells respond to changes in oxygen levels. The findings have implications in treating many diseases, including cancer, anaemia, heart attacks and strokes. These scientists had also shared the Albert Lasker Basic Medical Research Award in 2016. 

Nobel 2019

Left to Right: William G. Kaelin Jr., Sir Peter J. Ratcliffe, Gregg L. Semenza

If Semenza, Kaelin and Ratcliffe had one thing in common, besides their area of research, it is that they chose to publish houses of brick rather than mansions of straw. It sure took a while for the world to notice them, but it did.

About the papers that earned him the Lasker, Kaelin wrote, “Most would be considered quaint, preliminary and barely publishable today.” These papers would get him the Nobel Prize three years later.

Semenza and Kaelin woke up to the call from the Nobel media that day. While Semenza’s first reaction was to hug his wife, Kaelin told Adam Smith – the Chief Scientific Officer of Nobel media – how he missed his late wife on that occasion. Ratcliffe, on the other hand, was working on a grant when Smith called him. “I was writing and will continue to write an EU Synergy grant for collaborative work with friends and colleagues in Finland, and also my good friend and colleague Christopher Schofield, so of course the EU’s on our minds at the moment, and we’re writing a Synergy grant. And despite this good news, I guess I’ll continue doing that and meet the deadline,” Ratcliffe said.

What made these scientists embark on their journey in research is worth knowing. In an interview with The Journal of Clinical Investigation (JCI) in 2016, Semenza said that it was his high school biology teacher, Rose Nelson, who inspired him to pursue biology. “I had her as a freshman for biology and then as a senior for AP biology when it was genetics within biology that I got really excited about. With her help, I was able to enrol in an NSF-sponsored summer program at the Boyce Thompson Institute for plant research. It was really my first exposure to research and experiments,” he said. His interest in genetics and his meeting with a family friend’s child, who had Down syndrome, motivated him to pursue MD-PhD to study genetics and to care for those with genetic disorders.

It wasn’t easy for him at this stage either. Being the first graduate student of the lab with a very ambitious project in hand, he had reached the stage where he felt it wasn’t working out. He then switched to another lab at Children’s Hospital of Philadelphia in the second year, where he studied β-thalassemia.

“I was tasked with studying an unusual family, where one of the alleles was a silent carrier,” Semenza told JCI. “Normally, you can tell from looking at the blood cells whether someone is a carrier. In this case, it was the father who was an obligate carrier, as he had two affected children, but you couldn’t tell he was a carrier. It was suggested that the mutation was in some way different; this was going to be my project. The idea was that you take the blood, isolate the DNA, make a library, pull out the β-globin gene, and sequence it. I did all that and at the end of one year, I got the sequence, and the mutation was the exact same mutation as the previous study, which meant that somehow the clone had become contaminated, and the whole thing had been for nothing. So now I was going to have to start over the third time. I went back, started over again; things went smoothly because technically I’d already done it, and we went through the project and got an answer.”

He then moved to Johns Hopkins for his post-doctoral education, where he worked with Haig Kazazian and Stylianos Antonarakis – leaders in finding the molecular basis of β-thalassemia. He started working on this gene called Erythropoietin (EPO), which Chuck Shoemaker from Genetics Institute in Cambridge had asked Kazazian and Antonarakis to consider. Semenza tried to identify the DNA sequences in the gene responsible for its expression in different tissues. They put different fragments of human DNA spanning the EPO gene into mice and checked if and where the gene was expressed.

This was the turning point for Semenza. He figured that the gene was regulated by oxygen. Now, he had to understand where these DNA sequences regulated by oxygen were located. On investigating further, he realized that this sequence was in the DNA sequence that came after the gene (3’ flanking sequence). This was unusual as such regulating regions usually lie before the gene (5’ flanking sequence). But the data said that it was the 3’ flanking sequence. So, they took this sequence and put them in a plasmid which had a reporter. They then put this plasmid inside human cells grown in the dish and deprived them of oxygen. At low oxygen levels, the EPO gene would be expressed because of the sequence present in the plasmid. They then made smaller fragments of that sequence and repeated the process until they got down to 33 base pairs. On mutating individual nucleotides in this region, they found that the EPO gene expression was stopped.

“We suspected that there was a very important factor, which was binding to that sequence and was responsible for turning on the gene. And so, we tried to find the protein that was the key factor for turning on the EPO gene,” Semenza told JCI.

At this point, he was a young faculty with a post-doctoral fellow, Guang Wang. Semenza and Wang started looking for a protein that would bind to this DNA sequence (Hypoxia Responsive Element). The challenge was to figure out the conditions that allowed binding. They were also hoping to find something that would be present in the nucleus of cells with low oxygen (hypoxic) but absent in those with normal oxygen levels (normoxic). “Guang would do several of these experiments a day and had this stack of blots with negative results on his desk. I was thumbing through them one day, and I came across this one gel where there seemed to be a faint band in the hypoxic lane. I got all excited and said, ‘Did you see this? Did you see this?’ After optimizing the assay in a very short period of time, he generated really strong definitive results of a binding activity that we called hypoxia-inducible factor 1,” Semenza said.

For Ratcliffe, the start was serendipitous. In his Lasker acceptance speech, Ratcliffe reflects on an incident from his days at the Lancaster Royal Grammar School for the boys. “I was a terrible schoolboy chemist and following the career of some distant relative, I was keen to study industrial chemistry. One day the ethereal but formidable headmaster appeared in the chemistry laboratory, summoned me to one side, and said, ‘Ratcliffe, I think you should study medicine.’ I said ‘Yes, Sir’ decisively. Without further thought, the university application papers were changed accordingly,” he said. “To this day, I don’t really know whether he felt I would be a good doctor or a bad chemist. But the moment sticks with me as a reminder of the importance of serendipity in a scientific career, at least in mine,” he added.

He trained in Medicine as a Kidney specialist and started his research career fascinated by the extraordinary sensitivity with which the kidneys regulate the hormone Erythropoietin (EPO) to regulate red blood cell production. “I felt that the problem was interesting, conceivably attractable and there was a new opportunity for study with the cloning of the erythropoietin gene. But some people felt, with the emerging success of recombinant Erythropoietin, that understanding how the hormone was regulated was a niche area unlikely to be of very general importance. They advised me accordingly to study something else,” he said.

In the telephone interview with Nobel Media, Kaelin shared what drew him to science. “You know, I’m a big believer of curiosity-driven, hypothesis-driven research,” he said. “I know that’s complementary to other ways of generating knowledge but I think in the end what drew me to science and what draws a lot of scientists to science is that we like interesting puzzles, like clinical features of patients who had mutations in the VHL gene, were a curious constellation of findings but one way to unify them was there was some abnormality in the way the tumours they were developing were sensing and responding to oxygen, and we thought if we could understand that we could understand more globally how cells and tissues sense and respond to changes in oxygen.”

Little did these physician-scientists know while addressing their research problems, that they were reaching for the Nobel with their findings. But that’s the beauty of Science. Think about these Nobel laureates. As someone who made a serendipitous entry into medicine later pursuing an area of research, which many thought had no scope beyond the niche area of kidney research, Ratcliffe won the Nobel Prize for the findings that have immense physiological importance. Sharing the award with him are Semenza, who struggled in the early days of PhD and found his way through, and Kaelin, whose pre-medical school mentor remarked on his college transcript, “Mr. Kaelin appears to be a bright young man, whose future lies outside of the laboratory.” Their life and work are a testament to the fact that houses of brick stand the test of time.

Sources:

Kaelin Jr., William G. (2017). Publish houses of brick, not mansions of straw. Nature. Retrieved from https://www.nature.com/news/publish-houses-of-brick-not-mansions-of-straw-1.22029

Neill, Ushma S. (2016). A conversation with Gregg Semenza. The Journal of Clinical Investigation.  Retrieved from https://www.jci.org/articles/view/90960

Albert and Mary Lasker Foundation. Peter Ratcliffe, Acceptance Speech, 2016 Lasker Awards. Retrieved from https://www.youtube.com/watch?v=wB5gzwZMvTM

Albert and Mary Lasker Foundation. William Kaelin Jr, Acceptance Speech, 2016 Lasker Awards. Retrieved from https://www.youtube.com/watch?v=K2Ds_S48IWg&t=54s.

Sir Peter J. Ratcliffe Interview. Retrieved from https://www.nobelprize.org/prizes/medicine/2019/ratcliffe/interview/

William G. Kaelin Jr. Interview. Retrieved from https://www.nobelprize.org/prizes/medicine/2019/kaelin/interview/

Gregg L. Semenza Interview. Retrieved from https://www.nobelprize.org/prizes/medicine/2019/semenza/interview/

 

Joel P Joseph Biological Sciences, Medicine, News

Cancer drugs may not be working the way we think they work

Scientists at Cold Spring Harbor Laboratory (CSHL) have discovered that many anti-cancer drugs do not work the way we think they work. The study, led by Jason M. Sheltzer, evaluated 10 anti-cancer drugs in the pre-clinical or clinical trials. Findings of this research may help in establishing more stringent tests for drugs before trying them on humans.

cancer colorful word in the wooden background

Sheltzer’s earlier investigations of a protein, MELK, paved way to this study. Several reports had suggested that MELK was essential for the survival of cancer cells. But Sheltzer found otherwise – cancer cells survived even in the absence of MELK. They also found that an anti-cancer drug (OTS167), which the clinicians claimed would target MELK, killed cancer cells that were depleted of MELK. Clearly, OTS167 did not target MELK to kill the cancer cells.

Sheltzer adopted this strategy to study more anti-cancer drugs. The team shortlisted 10 anti-cancer drugs that were in pre-clinical or clinical testing. They selected drugs that clinicians claimed would stop the proliferation of cancer cells by targeting a single protein. The researchers then deleted the gene that coded for the claimed target protein using the CRISPR-Cas9 technology and checked if the cancer cells survived. But cancer cells were killed. This suggested that the drugs were not targeting these proteins.

The researchers particularly studied a drug (OTS964) targeting the protein PBK in greater detail. They gave enough time for cancer cells to accumulate mutations and develop resistance to OTS964 to find what protein the drug targeted. Cancer cells are genetically unstable and accumulate mutations over time. These mutations, resulting in changes in the protein they code for, restrain the drug from binding to the target protein. Knowing the genes that are mutated help us understand the actual target proteins. On analysis, they found that the gene coding for CDK11 had several mutations in it. This indicated that CDK11 was the actual target of this drug.

This may be one reason why 97 per cent of cancer drugs tested in clinical trials do not go on to receive US FDA approval. Understanding the accurate ‘mode of action’ of a drug increases the chances of its success. It is possible that the earlier experimental methods of inhibiting a gene or protein – RNAi and small molecule inhibitors – could be blocking some other protein in the cell. This may well the reason why drugs work differently than how we thought they would.

With advanced technologies like CRISPR-Cas9 technology, we can be more accurate. As the current study showed, this can be used as a method to test the claimed “mode of action” of the drug before they are tested on humans. This study also gives us a method to understand what proteins or genes are essential for the survival of cancer cells.

Pic Courtesy: China Daily