Caroline T. Tiemessen
Professor Caroline T. Tiemessen
DST/NRF Research Chair of HIV Vaccine Translational Research
University of the Witwatersrand
Head: Cell Biology, Centre for HIV and STIs
National Institute for Communicable Diseases, NHLS
Caroline Tiemessen heads the Cell Biology Research Laboratory within the Centre for HIV and STIs at the National Institute for Communicable Diseases (NICD), and holds a joint appointment as Research Professor at the University of the Witwatersrand. In 2013 she was awarded the DST/NRF Research Chair of HIV Vaccine Translational Research in the Faculty of Health Sciences at the University of the Witwatersrand, was appointed a member of the Academy of Science of South Africa (ASSAf). Research interests include the study of HIV vaccines and HIV cure (paediatric and adult). A focus is on natural resistance models which include maternal-infant HIV-1 transmission for studying protective immunity to HIV-1, and the study of long term nonprogressors and elite controllers to understand natural attenuation of disease progression. A more recent and major focus of research efforts is in the field of paediatric HIV cure. Here her laboratory is exploring viral reservoir and host biomarkers as part of an NIH U01-funded LEOPARD clinical trial currently being conducted in Johannesburg, and is intensely studying the recent case of the HIV-infected South African child in remission. This case offers a unique study opportunity to find clues as to what might make long-term remission possible for more individuals, and could help inform the search for the more challenging goal of a complete cure for HIV.
Title of the talk: Models for the study of HIV remission: elite and post-treatment controllers
There is widespread consensus that an HIV cure is required and is feasible. The ideal of controlling HIV-1 in the absence of antiretroviral treatment/ART (“functional cure” or remission) or eradicating HIV-1 (“eradicating cure”) will have enormous individual and public health benefits. The early establishment of latently HIV-1-infected CD4+ T-cells harbouring replication-competent virus remains the major obstacle to HIV cure or remission. Support for the importance of the timing of initiation of ART in relation to the time of HIV-1 acquisition comes from adult studies with the identification of “post-treatment controllers”, and from paediatric remission cases of the “Mississippi baby”, the “French teenager” and the “South African child”. There are many questions around why remission can be maintained consistently for some, while in other cases not at all, or for only for short periods of time before rebound occurs. This is reminiscent of the scenario of natural control of HIV-1 infection, where disease course ranges from very rapid progression on the one hand, to the opposite extreme that occurs in a very rare group of individuals called elite controllers – who suppress viral load to undetectable levels in the absence of ART. Unravelling the complexities of virus and host in the context of effective control of HIV-1 in cases of elite controllers and post-treatment controllers will provide much needed insights to inform strategies for HIV cure interventions.