T Cells Specific for a Mycobacterial Glycolipid Expand after Intravenous Bacillus Calmette-Guérin Vaccination.

Affiliation

Layton ED(1), Barman S(1), Wilburn DB(2), Yu KKQ(1), Smith MT(1), Altman JD(3), Scriba TJ(4), Tahiri N(5), Minnaard AJ(5), Roederer M(6), Seder RA(6), Darrah PA(6), Seshadri C(7)(8).
Author information:
(1)Department of Medicine, University of Washington School of Medicine, Seattle, WA 98109.
(2)Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195.
(3)National Institutes of Health Tetramer Core Facility, Emory University, Atlanta, GA 30329.
(4)South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 9747, South Africa.
(5)Stratingh Institute for Chemistry, University of Groningen 7925, Groningen, the Netherlands.
(6)Vaccine Research Center, National Institutes of Health, Bethesda, MD 20892; and.
(7)Department of Medicine, University of Washington School of Medicine, Seattle, WA 98109; [Email]
(8)Tuberculosis Research and Training Center, University of Washington, Seattle, WA 98109.

Abstract

Intradermal vaccination with Mycobacterium bovis bacillus Calmette-Guérin (BCG) protects infants from disseminated tuberculosis, and i.v. BCG protects nonhuman primates (NHP) against pulmonary and extrapulmonary tuberculosis. In humans and NHP, protection is thought to be mediated by T cells, which typically recognize bacterial peptide Ags bound to MHC proteins. However, during vertebrate evolution, T cells acquired the capacity to recognize lipid Ags bound to CD1a, CD1b, and CD1c proteins expressed on APCs. It is unknown whether BCG induces T cell immunity to mycobacterial lipids and whether CD1-restricted T cells are resident in the lung. In this study, we developed and validated Macaca mulatta (Mamu) CD1b and CD1c tetramers to probe ex vivo phenotypes and functions of T cells specific for glucose monomycolate (GMM), an immunodominant mycobacterial lipid Ag. We discovered that CD1b and CD1c present GMM to T cells in both humans and NHP. We show that GMM-specific T cells are expanded in rhesus macaque blood 4 wk after i.v. BCG, which has been shown to protect NHP with near-sterilizing efficacy upon M. tuberculosis challenge. After vaccination, these T cells are detected at high frequency within bronchoalveolar fluid and express CD69 and CD103, markers associated with resident memory T cells. Thus, our data expand the repertoire of T cells known to be induced by whole cell mycobacterial vaccines, such as BCG, and show that lipid Ag-specific T cells are resident in the lungs, where they may contribute to protective immunity.