Navigation
Public engagement

Becoming a Scientist

Read online for free

Print your own copy

Virus Fighter

Build a virus or fight a pandemic!

Play online

Maya's Marvellous Medicine

Read online for free

Print your own copy

Battle Robots of the Blood

Read online for free

Print your own copy

Just for Kids! All about Coronavirus

Read online for free

Print your own copy

Archive
LabListon on Twitter

Entries from July 1, 2010 - July 31, 2010

Tuesday
Jul272010

Juvenile Diabetes Research Foundation

Good news in funding appears to come in pairs. The Juvenile Diabetes Research Foundation is supporting the Autoimmune Genetics Laboratory through a Career Development Award. This is a grant that I am particularly happy to receive, not just for the science that will come out of it, but because I have been a long-time admirer of the JDRF, who tirelessly raise money for research on type 1 diabetes. They are not only the leading sponsor of type 1 diabetes research (spending over $1.4 billion on research since 1970), but also take an active role in coordinating researchers and integrating patient into trials to ensure that the best results come from the money spent. As a PhD student with Chris Goodnow, I always joined in the Walk for the Cure fundraiser, and JDRF sponsored my conference travel to the International Immunology Congress in 2004.

Now the JDRF is supporting our research project on the contribution of non-hematopoietic defects to autoimmune diabetes:

The Non-obese diabetic (NOD) mouse is one of the best studied models of common autoimmune disease in humans, with the spontaneous development of autoimmune diabetes. Similar to the way multiple autoimmune diseases run in families of diabetic patients, the NOD mouse strain is also susceptible to multiple autoimmune diseases, with specific disease development depending on slight alterations in the environment and genetics. These results demonstrate the complexity of autoimmune genetics – in both human families and inbred mouse strains there appear to be a subset of genetic loci that skew the immune system towards dysfunction and an additional subset of genetic loci that result in this immune damage affecting a particular target organ. In the case of NOD mice and type 1 diabetic patients these additional genetic factors result in damage to the beta islets of the pancreas. While the previous emphasis on type 1 diabetes was strictly on the immune system, this model suggests the important role the pancreas may play in the disease process. If certain individuals harbour genetic loci that increase the vulnerability of pancreatic islets to immune-mediated damage, the combination of immune and pancreatic loci could provoke a pathology not caused by either set of genes alone.

Current approaches to genetic mapping in both mice and humans are confounded by the large number of small gene associations and are not able to discriminate between these functional subsets of genetic loci. However, we have developed an alternative strategy for functional genetic mapping. Instead of mapping diabetes as the sole end-point, with small genetic contributions by multiple genes, we map discrete functional processes of diabetes development. This has three key advantages. Firstly, as simpler sub-traits there are fewer genes contributing, each with larger effects, making mapping to particular genes more feasible. Secondly, by mapping a functional process within diabetes we start out with functional information for every gene association we find. Thirdly, by mapping a series of functional processes and then building up this genetic information into diabetes as an overall result we gain a more comprehensive view of diabetes, as a network of genetic and environmental influences that cause disease by influencing multiple systems and processes.

In this project we propose to use the functional genetic mapping approach to probe the role of the pancreatic beta islets in the development of diabetes in the NOD mice. We have developed a transgenic model of islet-specific cellular stress which demonstrates that NOD mice have a genetic predisposition of increased vulnerability of the pancreatic islets to dying and hence the development of diabetes. This is a unique model to analyse the genetic, cellular and biochemical pathways that can be altered in the pancreas of diabetes-susceptible individuals, shedding light on the role the beta islets play in the development of disease.

Saturday
Jul242010

A breakthrough for HIV prevention?

This week a breakthrough for HIV prevention was announced in Science. AIDS researchers in South Africa just completed a long-term study of Tenofovir Gel, and found that the gel, inserted into the vagina before sex, results in a 40% HIV protection rate for women. With 900 women being followed up for 30 months, the results look very solid, and potentially even better than the headline figure of 39% protection. As with all such studies, the protection rate given is with average usage, not ideal usage. The average study participant only actually used the gel for ~75% of sexual intercourse occasions. For the "high adherers", the group using the vaginal gel for >80% of sexual intercourse occasions, the protection rate was 54%. How important is this breakthrough? In a way, it is both bigger and smaller than the headlines would suggest.

A new tool to fight HIV spread

In the age of vaccines with efficacy rates of >99%, a ~40% protection rate sounds rather poor. Furthermore, this is currently a form of protection only against heterosexual transmission of HIV to women, with no data yet on any protection granted to males having sex with a HIV+ woman or as an anal gel for male homosexual transmission. HIV acquisition by non-sexual routes, such as intravenous drug use, will of course be unaffected by the gel. This is a very poor efficacy rate when compared to condom use. A Cochrane meta-analysis has determined that consistent use of condoms results in an 85% protection rate against HIV, which can go as high as 95% with correct usage. The protective effect is only on par with that of male circumcision, which multiple randomized trials have found protects males from heterosexual HIV transmission at a rate of around 60%.

Is the new gel then completely redundant? A downgrade from the condom? No, not for a key population group - the women of southern Africa. The ten countries of southern Africa together constitute 35% of global HIV cases, with HIV reaching a hyper-endemic situation with 10-30% of adults infected with HIV. In this region, heterosexual spread is the dominant form of HIV transmission, and indeed the risk factor of greatest magnitude at the population level goes to married women. Condom usage in Africa is generally very poor, with an average of only 4.6 condoms available per man per year, due to low demand. Only 7% of women in southern Africa reported using a condom the last time they had sexual intercourse with a regular partner. In particular, women who are food insecure are 70% less likely to use a condom when having sex, with less personal control over sexual relationships. Other women may not use a condom during sex for more personal reference - such as trying to conceive. A vaginal gel therefore provides (partial) HIV protection for the first time to any women who would not otherwise use a condom during sex, either because of personal choice, lack of sexual control, or through a desire to become pregnant.

The other important consideration is that any protection results in a greater number of cases being prevented than the effectiveness of the protection to the individual. This is because each case stopped also prevents the flow-on cases which would have spread from the infected individual. It has been estimated that a weakly protective vaccine, with only a 50% protection rate and only given to 30% of the population, would reduce new HIV infections by more than half, over 15 years. These figures are comparable to the results for Tenofovir Gel, so if the maximal potential is realized, this breakthrough has the ability to halve new African HIV cases.

A tool that will sit idle?

The problem, of course, is that the potential of this gel will not be realized. In many ways, the HIV epidemic is not a problem waiting for a medical solution, but rather a problem waiting for a social and political solution. Consider mother-to-child HIV prevention. Current medical treatment of HIV+ women during pregnancy and after birth reduces the transmission rate to the child by more than 99%. Even in developing countries, the treatment program has over 98% efficacy. And yet these cases, almost entirely preventable under current treatment, make up 15% of global HIV cases and 40% of HIV cases in southern Africa, since only 33% of pregnant HIV+ women in Africa get any form of anti-HIV treatment, let alone the recommended treatment program.

Other strategies, which are already proven to work, could make similar impacts if broadly implemented. Widespread male circumcision would reduce HIV rates by 60% in males and, by reducing prevalence, 30% in females. Comprehensive sexual education focused on preventing new infections can be highly successful. An aggressive campaign of university HIV testing and near universal antiretroviral treatment would be capable of reducing new HIV infections by 95% within 5 years. Just the simple treatment of individuals with genital herpes with current antiherpatic drugs could be expected to reduce transmission of HIV in southern Africa by 50%.

No, a new tool to fight HIV is not going to stop the virus. Realistically, the current tools available could cut new HIV cases by 99% within the decade, if only they were implemented. The true scourge of HIV is that it attacks the marginalised in society, hitting regions of great poverty, infecting those on the receiving side of racial and sexual discrimination. The people that, quite frankly, too many people feel deserve to be sick. Being interwoven with issues of sexuality, drugs, race and poverty, people in power have not only been slow to move - they have often moved in the wrong direction, such as the $15 billion pledged in aid by George W. Bush, with its focus on replacing effective condom use with ineffective "abstinence only" programs.

A major part of the problem is certainly lack of resources, both funding and public health infrastructure. The response to HIV has been delayed, fragmented, inconsistent and grossly under-resourced. Lesotho launched a national voluntary counselling and testing campaign aiming at universal testing, which fell through due to a lack of resources. In South Africa only 28% of HIV+ people have access to antiretrovirals. In Zimbabwe only 4.4% of HIV+ pregnant women are receiving antiretroviral treatment to prevent mother to child transmission. In Nigeria 10% of all HIV transmission events are due to lack of funds for hospitals to screen transfused blood, a situation which requires only funding to remedy. However, funding is not the only impediment to an efficient HIV prevention campaign. Policy makers have repeatedly failed to spend limiting resources on HIV prevention, concentrating on medical treatment without adequate care and support. This is despite the cost of most HIV prevention techniques being well under the $4770 per infection prevented that it would take to create a cost savings compared to simple treatment. What is needed to end the HIV crisis is, in fact, simple in health terms and is difficult only in political implementation – a coordinated and adequately funded approach to integrate evidence-based HIV prevention strategies, in concert with major social and economic development efforts to eliminate gender disparities, race- and sexuality-based discrimination and extreme poverty.

Thursday
Jul222010

European Research Council funding

A major investment of my time last year and this year was in putting together an application for a European Research Council Start grant. The process was quite an ordeal, with both a substantial written grant and a challenging oral defense, probably consuming over 100 hours of my time. Fortunately, with excellent independent researchers in the laboratory, great research continued to be done in the laboratory while I was locked away with the computer.

Being open to researchers across Europe, in any discipline, the competition is fierce, however there are some large advantages to the ERC Start grant process: 1) the committee looks favourably upon large ideas, rather than safe ideas; 2) the competition is segregated according to career stage, so that I was only competing with other researchers less than five years out from their PhD; 3) the funding is sufficient in scale and duration to really put forward a grand plan. Just recently I found out that the application was approved, and the VIB put out the following press release:

VIB receives high score from European Research Council (ERC)
Two young top researchers awarded €1.5 million research grants!

Leuven - VIB landed two research grants worth 1.5 million euros each. The prestigious grants are courtesy of the European Research Council (ERC) and are aimed at giving talented young scientists the opportunity to develop their own research team. The honor fell to Adrian Liston and Patrik Verstreken, both recently transferred to VIB-K.U.Leuven from abroad.

The European Research Council
ERC was created to encourage excellent research in Europe. ERC starting grants give young talented researchers the opportunity to develop a research group. At present, there are still too few opportunities in Europe for young scientists to initiate and lead their own research, which is extremely unfortunate as it results in top researchers leaving the region to develop their careers elsewhere.

Adrian Liston studies autoimmune diseases.
The immune system is our body's defense system and allows it to fight off foreign substances and micro-organisms. In people with an autoimmune disease, the immune system has gone awry: it can no longer distinguish between the body's own and foreign substances and ends up attacking vital tissues and organs. Adrian Liston studies immune system cells (T cells) that are responsible for this malfunction. With his ERC research grant, he plans to bridge the gap between his research on mice models and humans. This may be a first step in the development of new therapies for autoimmune diseases.

Patrik Verstreken explores the communication between brain cells.
Brain disorders take a major toll on society. Many brain diseases are caused by the disruption of communication between brain cells. Finding a solution depends on understanding this communication in the smallest detail. Patrik Verstreken uses the fruit fly as his model organism for studying genes involved in the communication between brain cells. The ERC research grant gives him the opportunity to expand his research to more complex neural communication networks that control behavior. This step is crucial if we are to understand neurological disorders such as Parkinson's disease.