Loss of circulating CD4 T cells with B cell helper function during chronic HIV infection

PLoS Pathog. 2014 Jan 30;10(1):e1003853. doi: 10.1371/journal.ppat.1003853. eCollection 2014 Jan.

Abstract

The interaction between follicular T helper cells (TFH) and B cells in the lymph nodes and spleen has a major impact on the development of antigen-specific B cell responses during infection or vaccination. Recent studies described a functional equivalent of these cells among circulating CD4 T cells, referred to as peripheral TFH cells. Here, we characterize the phenotype and in vitro B cell helper activity of peripheral TFH populations, as well as the effect of HIV infection on these populations. In co-culture experiments we confirmed CXCR5+ cells from HIV-uninfected donors provide help to B cells and more specifically, we identified a CCR7(high)CXCR5(high)CCR6(high)PD-1(high) CD4 T cell population that secretes IL-21 and enhances isotype-switched immunoglobulin production. This population is significantly decreased in treatment-naïve, HIV-infected individuals and can be recovered after anti-retroviral therapy. We found impaired immunoglobulin production in co-cultures from HIV-infected individuals and found no correlation between the frequency of peripheral TFH cells and memory B cells, or with neutralization activity in untreated HIV infection in our cohort. Furthermore, we found that within the peripheral TFH population, the expression level of TFH-associated genes more closely resembles a memory, non-TFH population, as opposed to a TFH population. Overall, our data identify a heterogeneous population of circulating CD4 T cells that provides in vitro help to B cells, and challenges the origin of these cells as memory TFH cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Antibodies, Neutralizing / immunology*
  • Antigens, Differentiation / immunology
  • B-Lymphocytes / immunology*
  • Chronic Disease
  • Female
  • HIV Antibodies / immunology*
  • HIV Infections / immunology*
  • HIV Infections / pathology
  • HIV Infections / therapy
  • Humans
  • Immunologic Memory
  • Male
  • T-Lymphocytes, Helper-Inducer / immunology*
  • T-Lymphocytes, Helper-Inducer / pathology

Substances

  • Antibodies, Neutralizing
  • Antigens, Differentiation
  • HIV Antibodies