The search for an effective AIDS vaccine began a quarter-century ago and after a series of failures, there finally appears some reason to cheer. The first signs of success are beginning to emerge, ironically, from a trial (RV144) that seemed destined to flop. The two vaccine candidates — ALVAC-HIV and AIDSVAX — used in the prime-boost trial conducted in Thailand from 2003 to 2009 failed in their prime objectives when each vaccine was tested individually. However, the trial, which involved more than 16,000 healthy volunteers, showed a statistically significant protection rate of 31 per cent in one of the three analyses performed. Further analysis of the trial data has revealed something more interesting. During an AIDS Vaccine Conference held recently in Bangkok, scientists reported the discovery of molecular clues that might have played a crucial role in the vaccine’s performance. Forty-one volunteers who received the vaccine and contracted HIV, and 205 others who received the vaccine but did not get infected with the virus, were chosen for some detailed investigations. Much to their surprise, the scientists found distinct antibodies that provided protection against or made the volunteers vulnerable to HIV infection. A Y-shaped immune molecule called an immunoglobulin G (IgG) was found in the blood of those who were not infected. It turned out that this molecule had the ability to recognise a particular portion of HIV’s outer covering and hence was able to confer better protection. On the other hand, another antibody (IgA) that recognised different portions of the HIV’s outer covering made people more susceptible. According to Nature, these people were 54 per cent more likely to become infected than those who did not have this antibody.
This is the first time a clinical trial has provided interesting leads that hold the promise of advancing AIDS vaccine research. Scientists are already planning animal studies to test the effectiveness of these antibodies. Three human trials using the same vaccines are also likely to start on a small scale in Thailand next year. The results from such studies may tell us if the antibodies caused the protection against HIV or if other factors played a role. But one thing is certain — the outer covering that conferred protection will become one of the most studied aspects of the virus. Only further trials in different populations can ascertain if the antibodies will be able to confer the same level of protection when used in other HIV vaccines and against other HIV strains. There is a ray of hope, but the need to temper optimism with caution stands out in a field littered with failures and disappointments.
Keywords: AIDS vaccine, HIV, AIDS, clinical trials
The work of these scientists is indeed a noble gesture commended by the scientist community. Though am not a critic, I feel that it's not just enough working on an aspect of the HIV virus, talking about the protein coat that is inducing the antibody responses. Because of their unique nature of overcoming the job of our immune potentials by evasive mechanisms plus the host of different strains and serovars, a combination of protein inhibitors that will act on all types of the glycoproteins found on the coat surfaces have to be made to achieve the objective of preventing attachment of the viruses to our immune cells. Keep the hope alive.
Glad to see the little hope of ray in AIDS vaccine search,definitely it will bring smile to many innocent sufferers!
I think discovery of vaccine can be a milestone in medicinal era. But this virus in human race is a result of sordid character. We should try to sort out this problem also. Otherwise any other virus can hit the human race more harshly than AIDS did.
The possible emergence of a vaccine against AIDS is a comforting piece of news. HIV has played havoc with lives of people. The innocent infants born with HIV through their infected parents or a possible blood transfusion during process of birth have to bear the cross for no sin of theirs. The school children have to bear the brunt as they were denied admission, due to the needless social stigma and unfounded fears of contagion attached to the plague. We had read an absorbing news report on the initial days of discovery of the disease. Some brutish elemnts, who descended to sexually assault a hapless woman took to their heels at her shouting that she was HIV infected. Once I noticed a railway engineer stepping into a hair-dressing saloon with a box carrying the paraphernalia for the task, possibly to avert the use of the barber's implements. Such was the nightmare people were mired in , when AIDS became popular news. However, we hope IgG molecule would soon help materialise a cure.
A good news for human race.I salute the commendable efforts of whole team involve in this noble research. But in my view ,we must follow the golden rule of -" prevention is better then cure"
Virus which is trasmitted from animals has created an atmosphere of fear in the human fraternity.Hard work of the scientists from all over the world is really appreciable.Their efforts have shown some light of hope to us.Thanks to all of them.
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