Research

Precisely controlling latent reservoirs

An essential question for HIV cure research is: how small must HIV reservoirs be to achieve sustained remission without antiretroviral drugs? Antiretroviral therapy (ART) effectively controls HIV replication, but it is not a cure. Thus, considerable effort is devoted to developing treatments that reduce viral reservoirs and boost antiviral immunity. However, one of the enduring questions for HIV research is how far these interventions must reduce viral reservoirs to attain clinically relevant periods of HIV remission after stopping ART. To address this question, we developed a simian immunodeficiency virus (SIV) model to precisely set the size of latent reservoirs in rhesus macaques. We use this model to establish extremely small SIV reservoirs—determining the impact of small viral reservoirs on the timing of viral rebound and antiviral immune responses’ ability to control virus replication after ART withdrawal.

Isolating monoclonal antibodies

We have developed methods for isolating antibodies from individual B cells. Currently, we are isolating monoclonal antibodies that bind individual macaque major histocompatibility complex (MHC) and killer-immunoglobulin-like receptor (KIR) molecules; the anti-MHC antibodies are available to the scientific community through the Nonhuman Primate Reagent Resource. In addition, we offer a monoclonal antibody cloning service through the WNPRC Immunology Services unit.

Our paper describing isolating an anti-MHC antibody: Isolating an anti-Mamu-A1*001 antibody

Dog leukocyte antigen (DLA)-88 genotyping

Major histocompatibility complex class I (MHC-I) are cell surface molecules that enable the immune system to distinguish between healthy and diseased cells. Many versions of the MHC-I genes exist within human and animal populations, with specific MHC-I variants associated with either good or poor disease outcomes. To aid disease association studied in dogs, we are adapting next-generation sequencing technologies to improve canine MHC genotyping.

Mapping minor histocompatibility antigens

Minor histocompatibility antigens (mHAgs) are MHC-bound peptides on cell surfaces that can stimulate immune responses after organ transplants and arise from genetic differences between the organ donor and recipients. Identifying mHAgs is challenging due to the size of the genome and the number of potential differences between individuals. We have developed a process to map mHAg in Mauritian cynomolgus macaques using a combination of cellular immunology, genomics, and bioinformatics.

Our paper identifying the first nonhuman primate mHAg.

 

The conceptual outline for mapping mHAgs in Mauritian cynomolgus macaques. (1) exome sequence the genomes of MHC-identical MCM, (2) generate bulk mHAg-reactive T cell lines, (3) single-cell sort mHAg-reactive T-cell clones, (4) test clones against a panel of BLCL from exome sequenced MCM, (5) group into BLCL that induce clone reactivity or non-reactivity, and (6) segregation analysis to identify candidate mHAgs.