Immunity to HIV

Immunity to HIV

AIDS TREATMENT UPDATE Issue 26 - Feburary 1995
Keith Alcorn

British researchers in The Gambia have discovered that three out of six prostitutes who are not infected with HIV despite being repeatedly exposed to the virus may have acquired immunity. The three women have cytotoxic (cell-killing) T-cells that can kill HIV-infected cells in the lab. According to Dr Sarah Rowland-Jones, who led the study, "there is a distinct possibility that they have produced an immune response that has destroyed the virus".

The research lends support to the view that in some people who are exposed to the virus the immune response is sufficiently effective that it prevents infection from becoming established. A similar immune response has previously been detected in some laboratory workers known to have been exposed to HIV-infected blood, in some HIV-negative babies of HIV-positive mothers and some sexual partners of HIV-positive people.

Studies in macaque monkeys suggest that one reason why humans may avoid HIV infection is because they develop immunity after exposure to a low dose of HIV. But this immunity may not be permanent; cytotoxic T-cell production could be affected by overall health, or may require periodic re-exposure to HIV to maintain any protective effect.

Cytotoxic T-cells, or CD8 cells, are so-called because they are able to recognise virus-infected T-cells and destroy them. They play an important role in controlling all viral infections and high levels of these cells are also associated with good health in people who have been infected with HIV for ten to fifteen years. Professor Jay Levy of the University of California believes that his research shows that cytotoxic T-cells play the key role in controlling HIV infection in the body by producing substances that can kill HIV. Several studies are now underway in the USA to investigate whether cloning huge numbers of the cytotoxic T-cells and transfusing them into the bodies of HIV-positive people who are becoming unwell has an impact on their condition. For more information see issue 21/22 of AIDS Treatment Update.

9502
ATU2605

Always watch for outdated information. This article first appeared in 1995. This material is designed to support, not replace, the relationship that exists between you and your doctor.

Copyright © 1995 - AIDS Treatment Update. Permission granted for noncommercial reproduction, provided that our address and phone number are included if more than short quotations are used. Subscription lists are kept confidential. NAM Publications 16a Clapham Common Southside, London, England SW4 7AB; TEL: 01-71-627-3200 (from outside the UK: +44-171-627-3200); FAX: 01-71-627-3101 (from outside the UK: +44=171-627-3101) info@nam.org.uk http://www.nam.org.uk

This information is designed to support, not replace, the relationship that exists between you and your doctor.
©1995. AEGIS.