Molecular basis of myelomonocytic receptor function in HIV-1 infection ABSTRACT Harnessing the potent antiviral activities of human immunodeficiency virus (HIV)-1-specific T cells is critical to the design and development of effective HIV-1 vaccines and immunogens. To do so, a clear understanding of the precise molecular mechanisms that influence the evolution and immunoregulatory function of these cells is needed. In previous collaborative work, the PI and co-PI discovered a novel regulatory mechanism for HIV-1-specific T cells, which depends on the interactions of inhibitory and activating myelomonocytic major histocompatibility complex class I (MHC-I) receptors on dendritic cells and monocytes with HIV-1 cytotoxic T lymphocyte (CTL) epitope/MHC-I complexes. We have found (i) that binding between these molecules is both antigenic peptide- and human leukocyte antigen (HLA) allele- specific, (ii) that HIV-1 CTL escape mutations increase peptide/MHC-I (pMHC-I) affinities for inhibitory myelomonocytic receptors causing dendritic cells to become tolerogenic, and (iii) that HLA class I alleles that are known to be HIV-1-protective in humans bind activating myelomonocytic receptors with increased relative affinities. In these ways, and perhaps others, myelomonocytic receptors play key and previously unrecognized immunoregulatory roles in the adaptive immune response to HIV-1 viremia. Here, we propose that determining the molecular basis of pMHC-I/myelomonocytic receptor interactions and that the targeted manipulation of these binding events will lead to novel and improved HIV-1 vaccines and immunogens.
We aim to determine a comprehensive structural, energetic and functional basis for molecular specificity in pMHC-I/myelomonocytic receptor interactions in order to provide a clear rational for including specific peptide epitopes in HIV-1 vaccines and to engineer affinity-matured myelomonocytic receptor variants to act as HIV-1 immunogens.

Public Health Relevance

Molecular basis of myelomonocytic receptor function in HIV-1 infection More than 30 million individuals are currently infected with human immunodeficiency virus (HIV)-1 worldwide, and in the year 2007 alone 2.7 million additional individuals were infected with the virus and a further 2 million individuals died of AIDS. While relatively effective anti-retroviral therapy exists, it is widely available only in first world countries, and some 95 percent of HIV-1-infected individuals reside in the developing world, and thus, the development of an effective HIV-1 vaccine remains an outstanding global health goal. Our proposed studies are aimed at elucidating critical molecular mechanisms by which HIV-1 infection progresses in humans to drive innovation in HIV-1 vaccine design and at engineering novel protein-based therapeutics to counteract HIV-1 infection.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI087452-05
Application #
8389623
Study Section
AIDS Molecular and Cellular Biology Study Section (AMCB)
Program Officer
Embry, Alan C
Project Start
2009-12-01
Project End
2014-11-30
Budget Start
2012-12-01
Budget End
2013-11-30
Support Year
5
Fiscal Year
2013
Total Cost
$361,538
Indirect Cost
$93,060
Name
University of Maryland Baltimore
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
188435911
City
Baltimore
State
MD
Country
United States
Zip Code
21201
Bashirova, Arman A; Martin-Gayo, Enrique; Jones, Des C et al. (2014) LILRB2 interaction with HLA class I correlates with control of HIV-1 infection. PLoS Genet 10:e1004196