HIV Prevention Workshop

9 December 2015

Delegates from the HIV Prevention Workshop that was held in Jozini, KwaZulu-Natal

The 6th annual HIV Prevention workshop held in Jozini, KwaZulu-Natal, South Africa from 17-20 Nov 2015, was hosted by CAPRISA, the Ragon Institute, and the HIV Pathogenesis Program and attended by approximately 80 scientists from various local and international research institutions.

Sessions focused on understanding HIV transmission, particularly at the mucosal level, passive transfer of broadly neutralizing HIV antibodies, active vaccination strategies against HIV, and a variety of other pathogenesis and basic immunology topics.  

CAPRISA’s Director, Salim Abdool Karim, set the stage for the meeting, reminding us of the need for better combination HIV prevention within the scope of the ongoing HIV pandemic. He said that while new cases of HIV are declining globally and in South Africa, “the rate of decline has slowed and new products that do not require regular adherence are urgently needed, especially for young women”.

In the HIV transmission session Tom Hope presented exciting new data on the first mucosal cells infected in the macaque model of SIV. Jo-Ann Passmore presented on an expansion of studies of mucosal inflammation in young women. Presentations from Ashley Haase and Adam Burgener highlighted the important role of the mucosal barrier in protecting against HIV transmission. Aida Sivro presented on CD4+ T cell correlates of HIV acquisition in the CAPRISA004 study.
A large segment of the meeting focused on broadly neutralizing antibodies (bNAbs) against HIV. This included basic questions about how to induce bNAbs either in natural infection or by active vaccination, whether this be the story of how CAP256 gained breadth (Jinal Bhiman), the immunogenicity of the trimer (Dennis Burton), or a more rational approach toward somatic hypermutation using VRC01 as a model (Bill Schief).

These talks were augmented by engaging presentations on basic B cell immunology, including the rules that govern clonal expansion (Gabriel Victora), modeling affitinity maturation (Arup Chackaborty), and how intracellular adjuvants can stimulate B cell activity (Batista Fecundo). From a more practical perspective, thoughts on how to deliver bNAbs were proposed in talks by John Mascola (passive transfer of bNAbs), Alex Balzacs (gene therapy), and Dan Barouch (active vaccination with Adenovirus vectors). All of this was considered in light of the fact that a study of passive transfer of VRC01 was just approved by the Medicines Control Council (MCC) in South Africa while the meeting was in progress. An open discussion followed on where passive transfer fit in the context of overall strategies toward long-acting PrEP.
Several other highlights included an update on the immunology of very acute HIV infection in the FRESH study (Jenn Maroa, Zaza Ndlovu, and Kamini Gounder), HIV-infected children who progress slowly despite high viral loads (Philip Goulder), the mechanism of action of PD1 (John Wherry), and several others.

The meeting ended on a hopeful note, with many expressing optimism that several new HIV prevention modalities may be within reach in the next few years.  

Dr Lyle Mckinnon