Wong, EmilyAkilimali, Ngomu AkeemGovender, PamlaSullivan, Zuri A.Cosgrove, CormacPillay, MonaLewinsohn, David M.Bishai, William R.Walker, BruceNdung'u, ThumbiKlenerman, PaulKasprowicz, Victoria Olivia2014-03-112013Wong, E. B., N. A. Akilimali, P. Govender, Z. A. Sullivan, C. Cosgrove, M. Pillay, D. M. Lewinsohn, et al. 2013. “Low Levels of Peripheral CD161++CD8+ Mucosal Associated Invariant T (MAIT) Cells Are Found in HIV and HIV/TB Co-Infection.” PLoS ONE 8 (12): e83474. doi:10.1371/journal.pone.0083474. http://dx.doi.org/10.1371/journal.pone.0083474.1932-6203http://nrs.harvard.edu/urn-3:HUL.InstRepos:11879516Background: High expression of CD161 on CD8+ T cells is associated with a population of cells thought to play a role in mucosal immunity. We wished to investigate this subset in an HIV and Mycobacterium tuberculosis (MTB) endemic African setting. Methods: A flow cytometric approach was used to assess the frequency and phenotype of CD161++CD8+ T cells. 80 individuals were recruited for cross-sectional analysis: controls (n = 18), latent MTB infection (LTBI) only (n = 16), pulmonary tuberculosis (TB) only (n = 8), HIV only (n = 13), HIV and LTBI co-infection (n = 15) and HIV and TB co-infection (n = 10). The impact of acute HIV infection was assessed in 5 individuals recruited within 3 weeks of infection. The frequency of CD161++CD8+ T cells was assessed prior to and during antiretroviral therapy (ART) in 14 HIV-positive patients. Results: CD161++CD8+ T cells expressed high levels of the HIV co-receptor CCR5, the tissue-homing marker CCR6, and the Mucosal-Associated Invariant T (MAIT) cell TCR Vα7.2. Acute and chronic HIV were associated with lower frequencies of CD161++CD8+ T cells, which did not correlate with CD4 count or HIV viral load. ART was not associated with an increase in CD161++CD8+ T cell frequency. There was a trend towards lower levels of CD161++CD8+ T cells in HIV-negative individuals with active and latent TB. In those co-infected with HIV and TB, CD161++CD8+ T cells were found at low levels similar to those seen in HIV mono-infection. Conclusions: The frequencies and phenotype of CD161++CD8+ T cells in this South African cohort are comparable to those published in European and US cohorts. Low-levels of this population were associated with acute and chronic HIV infection. Lower levels of the tissue-trophic CD161++ CD8+ T cell population may contribute to weakened mucosal immune defense, making HIV-infected subjects more susceptible to pulmonary and gastrointestinal infections and detrimentally impacting on host defense against TB.en-USBiologyImmunologyImmune CellsT CellsImmunopathologyMicrobiologyVirologyCo-InfectionsMedicineClinical Research DesignCross-Sectional StudiesInfectious DiseasesBacterial DiseasesTuberculosisViral DiseasesHIVRetrovirology and HIV immunopathogenesisJournal Article2014-03-1110.1371/journal.pone.0083474