WHAT: New discoveries about anti-HIV antibodies may bring researchers a step closer to creating an effective HIV vaccine, according to a new paper co-authored by scientists at the Vaccine Research Center of the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

Scientists know that an HIV-neutralizing antibody called b12 binds to gp120, an HIV surface protein, at one of the few areas of the virus that does not mutate: the site where gp120 initially attaches to human immune cells (http://www3.niaid.nih.gov/news/newsreleases/2007/b12antibody.htm). It was thought that exposing the human immune system to this site on gp120 would generate antibodies that, like b12, can neutralize HIV. Studies have found that for unknown reasons, however, the vast majority of antibodies that recognize this site do not block the virus from infecting cells. Now a new study solves this puzzle, suggesting that antibodies must home in precisely on the site of initial gp120 attachment to successfully neutralize HIV.

The gp120 protein usually appears on the surface of HIV and on infected cells in inactive forms of viral debris or non-functional viral spikes. Only rarely do gp120 molecules appear on the surface of the virus in a functional viral spike, which contains a cluster of three gp120 molecules, known as a trimer, in specific alignment. HIV uses this functional viral spike to bind to immune cells and infect them.

The new study shows that most antibodies able to bind to non-functional forms of gp120 cannot bind to gp120 in the functional viral spike and therefore cannot neutralize HIV. Further, the study demonstrates that the reason most anti-gp120 antibodies similar to b12 cannot bind to the functional viral spike is because of the way these antibodies attach to gp120. A close examination of two such antibodies illustrated that their binding positions on gp120 cause a key portion of the protein either to swing in or flare out in positions incompatible with the trimer structure. In contrast, the position of b12 antibody binding allows gp120 to neatly form its normal trimeric structure.

The scientists conclude that generating HIV neutralizing antibodies will require teaching the immune system to make antibodies that precisely target the site of vulnerability on gp120 as it appears in the functional viral spike rather than targeting the plentiful forms of viral debris such as single gp120 molecules.

ARTICLE: L Chen et al. Structural basis of immune evasion at the site of CD4 attachment on HIV-1 gp120. Science DOI 10.1126/science.1175868 (2009).

WHO: Peter D. Kwong, Ph.D., and John R. Mascola, M.D., chiefs of the Structural Biology Section and BSL-3 Core, respectively, in the NIAID Vaccine Research Center, as well as Gary J. Nabel, M.D., Ph.D., director of the Vaccine Research Center.

Source: Laura Sivitz

NIH/National Institute of Allergy and Infectious Diseases

HIV and sexual health charity Terrence Higgins Trust (THT) is calling for people across Shropshire, Telford & Wrekin to get involved in World AIDS Day (December 1) this year, either by attending an event, making a donation to support local HIV services, or wearing a red ribbon to raise awareness.

World AIDS Day, which has been running every December since 1988, is dedicated to raising awareness of HIV and AIDS. In the UK alone, over 80,000 people are living with HIV and over 7,000 are diagnosed every year.

The following events, run in collaboration with Shropshire Buddies & Body Positive, are taking place in Shropshire, Telford & Wrekin for World AIDS Day:

- County-wide Awareness Drive (various times and locations across Shropshire)
Friday 27 November (10.00am - 2.00pm): Newport High Street
Saturday 28 November (10.00am - 1.00pm): Wellington High Street
Saturday 28 November (9.00am - 6.00pm): Telford Shopping Centre
Tuesday 1 December (9.00am - 6.00pm): Pride Hill Shopping Centre, Shrewsbury
Saturday 5 December (10.00am - 1.00pm): Ludlow Market
THT staff and volunteers will be out in force at locations across Shropshire in the run up to and immediately after World AIDS Day, raising awareness of HIV, collecting donations, and handing out red ribbons.

- Tuesday 1 December (10.00am - 5.00pm): Day of Remembrance, St Laurence Church, Ludlow
St Laurences Church will be open all day for people to light a candle in remembrance and celebration, with an hour-long vigil from 12.00pm - 1.00pm. THT will provide a display with information on HIV and how to prevent it. The day will conclude at 4.45pm with prayers of remembrance.

- Tuesday 1 December (6.30pm - 8.00pm): Candle-Lit Vigil, The Square, Shrewsbury
THT will be holding a special candle-lit vigil to remember those that have died and to celebrate the lives of those with HIV today. The vigil is open to all, and will feature a reading by Reverend Mark Thomas, a performance by Heart and Soul Community Choir, and a two minute silence.

Lotte Hakeman, Centre Manager for THT in Shropshire, said “World AIDS Day is one of the most important events in THT’s calendar. Currently in the UK one in four people with HIV don’t know they have it, so it’s vital that we continue to raise awareness. We hope local people will get involved in some way, either by attending an event, making a donation, or just wearing a red ribbon.”

Source
Terrence Higgins Trust

HIV and sexual health charity, Terrence Higgins Trust (THT) is calling for people in Sandwell to get involved in World AIDS Day (December 1) this year, either by attending an event, making a donation to support local HIV services, or wearing a red ribbon to raise awareness.

World AIDS Day, which has been running every December since 1988, is dedicated to raising awareness of HIV and AIDS. In the UK alone, over 80,000 people are living with HIV and over 7,000 are diagnosed every year.

The following events are taking place in Sandwell for World AIDS Day this year:

- Saturday 21 November (3.00pm - 6.00pm): Open forum on HIV for English-speaking Africans
At THT’s Sandwell centre (290-292 High Street), there will be a special session for English-speaking Africans living locally, providing basic facts about how people can protect themselves from HIV, answering questions, and giving general information on World AIDS Day.

- Friday 27 November (3.00pm - 6.00pm): Open forum on HIV for French-speaking Africans
At THT’s Sandwell centre (290-292 High Street), there will be a special session for French-speaking Africans living locally, providing basic facts about how people can protect themselves from HIV, answering questions, and giving general information on World AIDS Day.

- Tuesday 1 December (10.00am - 4.00pm): Awareness drive, West Bromwich high street
Staff and volunteers from THT will be out in force on West Bromwich High Street, raising awareness of HIV, providing information on safer sex and giving out red ribbons.
Jane Morel, Regional Manager for THT in the West Midlands, said: “World AIDS Day is one of the most important events in THT’s calendar. Currently in the UK one in four people with HIV don’t know they have it, so it’s vital that we continue to raise awareness. We hope local people will get involved in some way, either by attending an event, making a donation, or just wearing a red ribbon.”

Source
Terrence Higgins Trust