Author Archives: Xin Dong

Another battlefield against HIV

Posted on April 4, 2019 | Leave a comment

HIV ( human immunodeficiency virus) is devastating: it has been estimated that over 63,000 people are living with HIV in Canada, that is to say, about 2 in 10,000 Canadians are carriers of HIV. Thanks to the life-saving medications and treatments like antiretroviral therapy (ART), the life expectancy of HIV carriers has been prolonged dramatically. However, these medications/treatments are not preventive, a large number of people are still getting infected every day: about 5,000 people get infected every day globally.

HIV Infection Statistics Source:https://www.flickr.com/photos/gdsdigital/4016463258

Historically, vaccines have been the most effective and cost-efficient weapon to prevent and eradicate infectious diseases like smallpox and measles. People have  assumed that vaccination will be the ultimate solution for HIV/AIDS. However, people haven’t won the battle this time. Scientists still haven’t found a single HIV vaccine that is effective, despite numerous time-consuming and expensive trials and experiments being conducted. The good news is, it is possible to speed up this painful process thanks to the work by Lang Wu and Tingting Yu.

Joint Model for HIV Vaccine Efficacy           URL:https://www.youtube.com/watch?v=rZ4hQeLQMfk

Last year, Professor Wu and his PhD student Tingting Yu at UBC (University of British Columbia) proposed an improved model to test the efficacy of vaccines based on the actual data from a clinical trial. Their work makes it possible to predict the likelihood of a certain individual being infected shortly after he/she gets the vaccination. With this in mind, researchers wouldn’t need to wait for years to tell the efficacy of a vaccine, instead, they could spend more time on developing and modifying new vaccines. Hopefully, this will speed up the development of HIV vaccine. 

On top of that, this model is not restricted to the assessment of the efficacy of HIV vaccines, according to Professor Wu, it can even be applied to predict the efficacy of treatments to other diseases, including cancer.

Written By Zoe Zhou, Xin Dong, Helen Hu, and Cameron Carvalho

 

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Young Blood, Old Soul

Posted on March 4, 2019 | Leave a comment

We often hear our grandparents telling their stories in those “good old days”. Indeed, who doesn’t want to stay forever young? Humans all experience physical and mental function declines as we are inevitably getting old and a lot of researches have been done so far to solve the mystery of aging. As evidence piles up, scientists say that the fountain of youth may lie in the blood.

Credit: Geralt

Can we reverse aging? Credit: Geralt

A recent paper published on Communications Biology showed a restored cognitive function in old mice after they received bone marrow transplantation from younger mice. They found that the level of a critical chemical, called CCL11, in blood was lowered in young bone marrow recipients mice and therefore reasoned that hematopoietic (blood cell generating) system may play a special part in regulating CCL11. This molecule is thought to have an inhibitory effect on nerve cells regeneration, which is a hallmark of aging.

However, this is not the first study in the field. In fact, discoveries on the rejuvenating power of young blood can be dated back as early as 1970s when scientists surgically connected the blood vessels of two lab mice with different ages so that they could share the same circulating blood. The old mice did become younger in terms of some physiological aspects. And more researches have found similar results and pinned down some critical molecules responsible for aging.

https://youtu.be/yKLlXRjktak

Blood transfusion reverses aging in mice
Credit: GeoBeats News

 

Those findings are very promising in helping us understand the mechanism of aging and develop drugs or therapies to fight some of the age-related disease, such as Alzheimer’s disease, in the future. However, our keenness to stay young has already been taken advantage of by some people. A start-up company in California called Ambrosia charged $8,000 to give clients one-time infusion with blood plasma from young people. Just in last month, FDA stated that “we’re concerned that some patients are being preyed upon by unscrupulous actors touting treatments of plasma from young donors as cures and remedies.” Soon after that, Ambrosia stopped their transfusion treatments.

Indeed, it’s not the time to jump the gun yet. First, those findings in animal models may or may not be applicable to humans yet: we still need more evidence to prove that. Secondly, such treatments are generally beyond the regulation of FDA, and they may bring other risks, such as blood-borne diseases, not to mention the societal consequences. Therefore, it seems we do have a long way to go before we find the real fountain of youth.

Written by Xin Dong

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Posted in Biological Sciences, Issues in Science, Science Communication

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“Vessel Baby” on the Way?

Posted on January 14, 2019 | Leave a comment

You probably have seen it more than once in Sci-fi movies: human babies are incubated in large fluid-filled vessels growing and waiting to come alive. I am not a big fan of such movies, but a recent study has made those scenes one step closer to reality.

A paper published on Nature  caught public’s attention in 2017. Scientists at the Children’s Hospital of Philadelphia kept eight premature lambs in an “artificial womb” system to allow those lambs to continue growing outside mother lambs’ body up to four weeks. The “artificial womb” looks a lot like a plastic bag filled with solution which mimics amniotic fluid in the real uterus. The baby lamb’s umbilical cord (containing blood vessels) was also connected to a bunch of tubes which provide oxygen and remove carbon dioxide at the same time.

Credit: Nature Communication

Schematic and Real Setup of Artificial Womb

Scientists of this study think such extra-uterine supporting system would be extremely beneficial for preterm human babies in the near future. Statistics show that infants have lower than 50% survival rate and may face lifelong health issues if they are born at or before 25 weeks. It is also one of the leading causes of new-born death and illness in the U.S. “These infants have an urgent need for a bridge between the mother’s womb and the outside world,” says  Alan W. Flake,  also the leading researcher of this study. With “artificial womb” like this, doctors and caregivers could keep a premature baby in a “uterus-like” environment longer enough for its important organs to grow and thus significantly reduces the rate of mortality and the risks of other complications.

Although this technology seems incredibly promising and considered as “a pretty momentous achievement” by  other researchers in the field, some people also raise ethical concerns about it. Can people abort a “vessel baby”? Who is going to raise the baby if both parents abandon it before it is born? They argue if artificial uterus further extends human’s ability to grow embryos and fetuses, such action would challenge our laws around issues like abortion and reproductive rights. However, other people embrace this technology which may become an option for homosexual males to have their own kids without the use of surrogate and allow women to have children without going through painful labour. Fortunately, we probably won’t see human babies “popped” out of such artificial system very soon since scientists need more time to tackle many technical issues and perfect the “womb”. This leaves the general public and policy makers some time to discuss all the ethical and legal considerations behind it.

Xin Dong

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Posted in Biological Sciences

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