During early HIV infection, the virus stably integrates in long-lived cellular reservoirs which persist despite continuous antiretroviral therapy (ART). ART initiation during early acute HIV infection may limit viral reservoir size, reduce immune activation and improve treatment outcomes and post-treatment virologic control in adults and children. There are scant data on reservoir dynamics and determinants from sub Saharan Africa, the region of the world with most global pediatric HIV. We have previously demonstrated influence of antibody- dependent cellular cytotoxicity (ADCC) on infant HIV acquisition and disease control. We have also demonstrated marked plasticity of the natural killer (NK) cell population over the course of infancy and NK suppression of HIV and acquisition in adult cohorts. It is plausible that these immune responses may influence reservoir establishment and decay. Understanding these determinants could inform vaccine or therapeutic strategies to accelerate reservoir eradication. We have followed infants and older children for >5-10 years with serial PBMC and plasma collection and have quantified HIV reservoir in a subset of children who started ART during the first year of life with viral suppression from these cohorts. We propose mechanistic virology/immunogy studies leveraging these unique repositories and to extend follow-up of these children to track longer term reservoir changes (>15 years since ART initiation in some children). Our overarching aim is to determine reservoir dynamics and decay using mathematical modeling and identify immune determinants of reservoir decline and size. This project will be led by multiple PIs (MPIs): Drs. John-Stewart and Lehman. With our combined expertise in pediatric HIV molecular epidemiology (John-Stewart, Wamalwa) virology (Lehman, Overbaugh), immunology (Slyker, Blish) and modeling (Holte, Matsen) we propose to model longitudinal reservoir dynamics, and determine effects of infant timing of HIV acquisition, ART timing, and the influence of infant immune activation, ADCC, and NK population characteristics on reservoir decline and size. These studies will provide novel data on reservoir dynamics during infancy and early childhood from sub Saharan Africa and will elucidate potential influence of immune activation, ADCC, and natural killer phenotype in reservoir containment, and ultimately inform intervention strategies for improved long-term management and reservoir control in HIV infected children.

Public Health Relevance

To cure or improve long-term control of pediatric HIV infection, it is critical to understand mechanisms by which the latent HIV reservoir is established and maintained in children despite long-term antiretroviral treatment (ART). This study aims to elucidate longitudinal HIV reservoir dynamics, size and decay and immune factors that influence the reservoir using unique specimen repositories from ART-treated Kenyan infant and child cohorts with 5-10 years of follow-up.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
5R01HD094718-04
Application #
9948741
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Lorenzo, Eric
Project Start
2017-09-01
Project End
2022-06-30
Budget Start
2020-07-01
Budget End
2021-06-30
Support Year
4
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of Washington
Department
Public Health & Prev Medicine
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
Pankau, Mark D; Wamalwa, Dalton; Benki-Nugent, Sarah et al. (2018) Decay of HIV DNA in the Reservoir and the Impact of Short Treatment Interruption in Kenyan Infants. Open Forum Infect Dis 5:ofx268