Phenotype and function of peripheral blood γδ T cells in HIV infection with tuberculosis

Abstract

Background: Although γδ T cells play an essential role in immunity against Human Immunodeficiency Virus (HIV) or Mycobacterium tuberculosis (MTB), they are poorly described in HIV infection with tuberculosis (TB). Methods: The phenotypic and functional properties of peripheral blood γδ T cells in patients with HIV/TB co-infection were analyzed compared to healthy controls and patients with HIV mono-infection or TB by direct intracellular cytokine staining (ICS). Results: The percentage of Vδ1 subset in HIV/TB group was significantly higher than that in TB group, while the decreased frequency of the Vδ2 and Vγ2Vδ2 subsets were observed in HIV/TB group than in TB group. The percentage of CD4+CD8- Vδ2 subset in HIV/TB group was markedly lower than in TB group. However, the percentage of CD4+CD8+ Vδ2 subset in HIV/TB group was markedly higher than HIV group or TB group. A lower percentage TNF-α and a higher percentage of IL-17A of Vδ2 subset were observed in HIV/TB group than that in HIV mono-infection. The percentage of perforin-producing Vδ2 subset was significantly lower in HIV/TB group than that in HIV group and TB group. Conclusions: Our data suggested that HIV/TB co-infection altered the balance of γδ T cell subsets. The influence of HIV/TB co-infection on the function of γδ T cells to produce cytokines was complicated, which will shed light on further investigations on the mechanisms of the immune response against HIV and/or MTB infection.