There is encouraging news this week on the prospects for an effective vaccine against HIV. A research team led by Professor Mariano Esteban at the Spanish Superior Scientific Research Council (CSIC) have announced that the vaccine MVA-B elicited a persistent immune response against HIV in 85% of volunteers in a phase 1 clinical trial. MVA-B is a therapeutic vaccine, it is not intended to block infection but rather to keep HIV levels in the body at levels well below those at which the virus can cause illness.
As a CSIC press release published online on EureakAlert! notes the MVA-B vaccine, created by inserting four HIV genes from the B subtype of HIV – the subtype accounting for most HIV infections in Europe and North America – into a vector derived from the Modified Ankara Vaccinia virus (a smallpox vaccine and shown to be safe in both animal studies and extensive human use), notes that:
In 2008, MVA-B already showed very high efficiency in mice as well as macaque monkeys against Simian’s immunodeficiency virus (SIV). Due to it’s high immunological response in humans, Phase I clinic trials will be conducted with HIV infected volunteers, to test its efficiency as a therapeutic vaccine.”
This is indeed true, a 2007 study in mice revealed that the MVA-B vaccine induced a strong immune response , while a paper published in 2008 by the same group demonstrated that a very similar MVA vaccine was able to induce a robust response involving both the HIV-1-specific CD4+ helper T-cells and CD8+ cytotoxic T cells in Rhesus macaques, and was able to control virus levels in macaques infected with the SHIV 89.6P hybrid virus whereas in unvaccinated monkeys the levels of virus rose and most developed an AIDS-like illness.
There is a question over whether the immune response generated by the MVA-B vaccine will be able to restrict HIV in humans, after all the MRK-Ad5 vaccine which failed to restrict the HIV virus in human trials and the pathogenic SIV MAC239 – considered a better model for HIV infection than SHIV 89.6p – in macaque monkeys had successfully controlled SHIV 89.6P in earlier studies.
Some reassurance on this issue comes from a study at Oregon Health and Science University (OHSU) that was announced earlier this year, where a group led by Dr. Louis Picker used a different vaccine vector – one based on Cytomegalovirus – to elicit a very similar broad immune response , with strong memory T-cell involvement, to that induced by MVA-B, and found that it induced long-term control the highly pathogenic SIV MAC239 strain. This was the highest degree of control demonstrated to date against this SIV strain, and indeed the cytomegalovirus vaccine is one of the first to demonstrate any ability to control SIV MAC239 levels.
Professor Esteban and his colleagues are certainly not resting on their laurels either, further clinical trials of the MVA-B vaccine are planned, to determine whether it can protect against HIV. In the meantime they are also seeking to improve on this vaccine. Earlier this year they published a paper in the open-access journal PloS One where they deleted a gene in the MVA vector to yield a new MVA-B vaccine that showed in mice a substantial increase in the magnitude and breath of the immune response compared with their original MVA-B vaccine, and an even better memory T-cell response. They now plan to evaluate this improved vaccine in a non-human primate model of HIV infection, and it will be interesting to see if they choose to use a more stringent model of infection such as SIV MAC239 rather than SHIV-89.6P.
Despite the setbacks and disappointments over the past two decades, it is clear from the work being done at the CSIC and OHSU that real progress is being made towards the development of both prophylactic and therapeutic vaccines against HIV, and it is just as clear that animal research continues to play a vital role in that progress.
Posted in News, Science News
Tagged aids, CSIC, hiv, HIV vaccine, immune response, immune system, Louis Picker, macaque, Mariano Esteban, mice, monkey, mouse, MVA-B, ohsu, Oregon Health and Science University, rhesus macaque, SHIV, SHIV-89.6P, SIV, SIV MAC239, Spanish Superior Scientific Research Council, T-cell, vaccine
Charities are regularly targeted by animal rights groups. Currently Animal Aid have been targeting some of the UKs biggest medical research charities including the British Heart Foundation (strong proponents of animal-based research), Cancer Research UK, Alzheimer’s Society and Parkinson’s UK. It was refreshing to see these charities responding to this national press by providing comments about the importance of animal research to their work (see also previous post on this):
Cancer Research UK – “We have strict ethical policies in relation to animals and follow rigorous government guidelines to ensure that animals are only used where there’s no alternative. Millions of people are alive thanks to life-saving treatments for cancer.”
British Heart Foundation – “Research funded by the BHF advances our understanding of the heart and circulatory system in order to improve our ability to prevent, diagnose, monitor and treat cardiovascular disease – saving and improving the lives of those people affected.”
Alzheimer’s Society – “Our research aims to move us closer to a cure and improve the quality of life of people with dementia. We strive to ensure that alternatives are used where possible, that the minimum number of animals are used and that researchers keep to the highest welfare standards.”
Parkinson’s UK – “Experiments involving accurate animal models of Parkinson’s are the key to improved drug screening and swifter movement into clinical trials involving humans for the best drugs that will allow people with Parkinson’s to lead a normal life, free from its symptoms.”
Nonetheless, many charities shy away from dealing with local press accusations, worrying that they may attract more attention, or simply that ignoring them will make the problem go away. So when Animal Aid made a verbal attack on Parkinson’s UK in a local Derby newspaper, it was a nice change to see the organisation respond with an equal measure of vigour.
IN her letter “Campaign seeks an end to research on animals” (Derby Telegraph, September 9) Dawn Spencer, of Animal Aid, makes a number of claims that cannot pass unchallenged.
Ms Spencer claimed that Parkinson’s UK does not wish people to find out how much we spend on research involving animals. I am happy to be open about this. Some 40% of the £4.6m we spend on research each year is on projects involving animals.
Our research work is governed by some of the toughest restrictions in the world, enforced by the Home Office. Details of our UK-funded research are on our website and the research strategy which specifies the development of new models is publicly available. Our policy is also on our website.
Ms Spencer said that “people wanted… alternative research using tissue cells”. We fund the Parkinson’s UK Brain Bank, which supplies donated human brain tissue for Parkinson’s research. However, the use of human tissue is not appropriate in every case.
She comments that “animal experiments can be unreliable and… misleading”. We know that research involving animals has been demonstrated to help to identify improved treatments, help us gain a greater understanding of the causes of the Parkinson’s and ultimately lead to the development of a cure.
Since the 1970s, the lives of millions of people with Parkinson’s have been transformed by taking the drug levodopa, which would not have been developed without the insights gained from research involving animals.
People who give money to Parkinson’s UK can choose to support other areas as we also fund campaigning and support to improve life for everyone affected by Parkinson’s. We’ll keep doing that until we find a cure.
Dr Kieran Breen
Director of research and innovation
Well done Dr. Breen for this clear and concise reply to Animal Aid.
For those charities considering speaking up in defence of life-saving medical research using animals, I recommend the follwing resources:
1. Understanding Animal Research – A Researchers’ Guide to Communication
2. Association of Medical Research Charities – Medical Research Charities and Animal Studies
3. Understanding Animal Research – Funding Animal Research: Communications Guidelines for Charities
There is no excuse for standing on the sidelines – it is time everyone stood up and spoke of the importance of animal testing.
Posted in Animal Rights News, Campus Activism, News
Tagged Alzheimer's Society, Animal Aid, animal research, animal testing, British Heart Foundation, Cancer Research UK, Kieran Breen, medical research charity, Parkinson's UK
We recently updated the statistics page of the website. Here are the highlights:
- The numbers of dogs used in research was at its lowest rate since measurements began in the 1970s. The current figure is less than 1/3 of its number in the late 1970s.
- The number of cats used remains at a general low (up very slightly from its historic low in 2009). The figure of 21, 578 is considerably smaller than the 74, 259 used in 1974.
- Primate research has risen slightly over the past decade, in part due to increasing amounts of research into neurodegerative diseases such as Alzheimer’s, which is expected to affect four times the number people in 2050 as it does today.
- Cats, dogs and primates together account for around 0.60% of animals used in research, making 2010 the fourth year this percentage has fallen.
The number of animals covered by the Animal Welfare Act used in medical research since 1973. This graph does not include the use of mice or rats.
Check out the statistics page now for more information
Posted in News, Science News
Tagged animal experiemtnation, animal research, animal testing, cats, dogs, medical research, primates, statistics, stats, us
I wanted to alert our viewers to a fantastic new blog I discovered recently.
The Ark Hive, written by Dr. Paul Foster, a Lecturer in Molecular Endocrinology at the University of Birmingham in the UK. According to his blog, Dr. Foster is:
“an experienced cancer researcher and pharmacologist with a strong interest in understanding how animals help advance medical research”
It is important that researchers, just like Dr. Foster, use their knowledge to help improve public understanding about the role of animals in research. Foster carefully balances scientific rigour with layman’s language to create a blog that is both enlightening and readable. Taken from his website is a short explanation of why he believes animal research is crucial.
Tests in intact animals are necessary to understand how a drug will work in the context of the myriad metabolic and homeostatic mechanisms that are active in vivo. Screening tests are commonly conducted with in vitro systems and isolated tissues or organs to identify and, in some cases, to act as a bioassay to help purify pharmacologically active agents. However, the variable processes of absorption, distribution within the organism, metabolism to either inactive or more active products, and excretion will modulate the expression of pharmacologic activity in vivo. The only way this modulation can be estimated is by studying the new drug in intact animals.
Aside from studies of pharmacologic activity, side effects of new drugs must be identified and an initial assessment made of their risk-to-benefit ratio. Again, mechanisms of action and effects on specific organs can be studied by using in vitro techniques. However, to identify unexpected adverse effects and to estimate the dosages that may be pharmacologically active without producing unwanted effects, in vivo studies must be conducted.
Speaking up about your own research doesn’t have to involve creating your own blog from scratch – feel free to jump on our bandwagon and offer to write a guest post on the merits of animal research for this blog.
As populations in many developed countries age an important question facing medical science is whether cognitive decline is insvitible as we age, and whether it can be presented or reversed.
Professor Carol A. Burns of the University of Arizona- who was last year awarded the prestigious Mika Salpeter Lifetime Achievement Award by the Society for Neuroscience – has written a fascinating account of what we have learned about aging and cognitive decline in recent decades. Her essay, which highlights the contribution made by animal research to advancing knowledge in this field, can be read in the September edition of The Scientist.
While developed societies face up to the challengs of an aging population, it is too easy to forget thet despite great advances in healthcare in most countries in recent decades far to many people still die from infectious diseases for which treatments are limited. One of these diseases is human trypanosomiasis – better known as sleeping sickness – which kills tens of thousands of people every year in sub-saharan Africa, and the current standard therapy for late stage disease, an arsenic-based medicine named melarsoprol, is highly toxic.
Now, as Understanding Animal Research report, a group of scientists based at the University of Glasgow have developed modified versions of melarsoprol that are highly effective in clearing trypanosome infection in mice, while avoiding the toxicity associated with melarosprol, publishing their findings in the open-access journal PLoS Neglected Tropical Diseases. It is to be hoped that this drug will soon be evaluated in clinical trials, as it has the potential to save many thousands of lives.
Posted in News, Science News
Tagged Aging, Carol A. Burns, cognitive decline, human trypanosomiasis, melarosprol, neuroscience, PLos Neglected Tropical Diseases, Sleeping sickness, Society for Neuroscience, the Scientist, trypanosome, University of Arizona