Researchers believe that Tat is a gene of HIV that regulates production of the virus.
This is according to the website www.hiv1tat-vaccines.info, which explains that, without Tat, the virus can enter a cell in the body, but can’t replicate.
It is produced very early after HIV-1 infection, even before the virus becomes part of the host cell’s genetic machinery, and is necessary for the virus to replicate and infect new cells. Acutely infected cells release it and it helps “recruit” and “activate” uninfected cells.
This provides new cells for the HIV-1 virus, the most prevalent strain, to infect, helping spread the HIV infection throughout the body.
According to the website, data suggests vaccination with Tat may modify the virus-host dynamics and control HIV-1 replication. This can be used in prevention and treatment, they believe.
A vaccination for HIV-1 positive people is believed to result in a reduced replication of the virus and slowing down of the disease. Researchers also think it can modify the virus-host dynamics at the beginning of infection.
The programme, funded by the Italian foreign affairs ministry, aims to strengthen healthcare services, establish a local good manufacturing practice-certified facility for recombinant protein vaccine products, and conduct phase two of the clinical trial.
In the services component, it will focus on HIV/Aids care and antiretroviral treatment, through helping upgrade and provide equipment to 40 health clinics in Gauteng, the Eastern Cape and Mpumalanga.
The production component will focus on developing a local production facility for vaccine manufacturing at The Biovac Institute (TBI) in Cape Town.
The vaccine component foresees the preparation and conduct of the “ISS-T003” clinical trial.
An independent international scientific advisory committee will monitor the programme periodically. The trial will be conducted at the Medunsa Clinical Research Unit (Mecru) at the University of Limpopo’s Ga-Rankuwa campus in Gauteng. An additional trial site, the Walter Sisulu University, HIV Vaccine Research Unit in Mthatha, Eastern Cape, is envisaged by the last quarter of 2011.
The ISS T-003 protocol has been approved by the Medicines Control Council and the Medunsa Research and Ethics Committee, according to the statement. It will involve the recruitment of 200 participants between 18 and 45 years old.
The objective is the evaluation of the immunogenicity (the ability of an antigen or vaccine to stimulate immune responses) of the vaccine candidate three times, at four weekly intervals, and to confirm the safety of the candidate vaccine as previously tested in Italy.
“Subjects eligible for the study will be individuals with chronic HIV infection on ARV treatment. The enrolment of the volunteers will be performed at Mecru.”