A team of scientists, at the Center for the AIDS Program of Research in South Africa (CAPRISA) found that two South African women infected with HIV were able to produce antibodies that neutralized and killed 88 percent of known strains of the virus.
Penny Moore, one of the lead scientists of the study published on Sunday in the journal Nature Medicine, said: ‘We’re hoping we can use this information to develop a vaccine that prompts the body’s immune system to make broadly neutralising antibodies’.
The women studied by CAPRISA for several years were able to produce ‘broadly neutralizing antibodies’, which can kill a wide range of the HIV virus, across different individuals and overcoming regional variations.
According to the study, the virus formed a layer of a sugar (called glycan) to protect itself from the common, strain-specific antibodies of the two women.
The study however found that glycan proved to be what Moore called the virus’s ‘Achilles heel’.
The women produced broadly neutralizing antibodies that targeted and bonded with glycan, thus blocking the virus from infecting healthy cells.
According to CAPRISA director Salim Abdool Karim, these antibodies could be the key to developing an HIV vaccine.
Speaking with IRIN/PlusNews he said: ‘The holy grail of HIV prevention is a safe, effective HIV vaccine.
‘This discovery provides new clues on how vaccines could be designed to elicit broadly neutralizing antibodies.’
The researchers stress that vaccine based on these antibodies will take several years to develop.
The solution may in fact be a series of different vaccines that will mimic the HIV infection, its progression and the body’s response.
Moore said: ‘[We would like to see] if we could trick [the] immune system to go through the same arms race it went through in these two women, without HIV infection’.
The research is co-funded by the US government and South Africa’s Ministry of Science and Technology.
The next phase of the research is produce a microbicide (substance whose purpose is to reduce the infectivity a virus).
If the microbicide would be successful in follow-up trials, the South African government plans to begin local production of its active ingredient to ensure affordability and reduce dependence on foreign importers.
South African Health Minister Aaron Motsoaledi congratulated researchers and acknowledged the two women’s contributions: ‘I wish to thank these women for allowing their experiences to be studied for the benefit of all us.
‘Sometimes, we forget about [study participants], but I think they are also scientists in one way or another. Without contributions like theirs, even the best idea cannot be tested.’
One of the women is healthy living with her partner and HIV-negative children in Durban.
The other unfortunately died of extensively drug-resistant tuberculosis about a year ago.
Karim stated: ‘Such are the challenges we deal with on a daily basis in our country with HIV patients.
‘But her specimens, her virus, continue to inform our work and enable us to understand [HIV] so, in many ways, she’s left a lasting legacy.’