HIV-Infected Spleens Present Altered Follicular Helper T Cell (Tfh) Subsets and Skewed B Cell Maturation

PLoS One. 2015 Oct 26;10(10):e0140978. doi: 10.1371/journal.pone.0140978. eCollection 2015.

Abstract

Follicular helper T (Tfh) cells within secondary lymphoid organs control multiple steps of B cell maturation and antibody (Ab) production. HIV-1 infection is associated with an altered B cell differentiation and Tfh isolated from lymph nodes of HIV-infected (HIV+) individuals provide inadequate B cell help in vitro. However, the mechanisms underlying this impairment of Tfh function are not fully defined. Using a unique collection of splenocytes, we compared the frequency, phenotype and transcriptome of Tfh subsets in spleens from HIV negative (HIV-) and HIV+ subjects. We observed an increase of CXCR5+PD-1highCD57-Tfh and germinal center (GC) CD57+ Tfh in HIV+ spleens. Both subsets showed a reduced mRNA expression of the transcription factor STAT-3, co-stimulatory, regulatory and signal transduction molecules as compared to HIV- spleens. Similarly, Foxp3 expressing follicular regulatory T (Tfr) cells were increased, suggesting sustained GC reactions in chronically HIV+ spleens. As a consequence, GC B cell populations were expanded, however, complete maturation into memory B cells was reduced in HIV+ spleens where we evidenced a compromised production of B cell-activating cytokines such as IL-4 and IL-10. Collectively our data indicate that, although Tfh proliferation and GC reactions seem to be ongoing in HIV-infected spleens, Tfh "differentiation" and expression of costimulatory molecules is skewed with a profound effect on B cell maturation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • B-Lymphocytes / physiology*
  • Cell Differentiation / physiology
  • Cytokines / analysis
  • DNA, Viral / metabolism
  • Flow Cytometry
  • Gene Expression Profiling
  • HIV Infections / immunology*
  • HIV Infections / pathology
  • Humans
  • Real-Time Polymerase Chain Reaction
  • STAT3 Transcription Factor / analysis
  • Spleen / chemistry
  • Spleen / cytology
  • Spleen / immunology
  • Spleen / pathology*
  • T-Lymphocytes, Helper-Inducer / physiology*
  • Virus Integration

Substances

  • Cytokines
  • DNA, Viral
  • STAT3 Transcription Factor
  • STAT3 protein, human

Grants and funding

This work was supported by the Agence Nationale de Recherche sur le SIDA et les hépatites virales (ANRS) and INSERM, by the French government’s “Investissement d’Avenir” Program, Laboratoire d’excellence “Integrative Biology of Emerging Infectious Diseases” (ANR-10-LABX-62-IBEID) and by the CutHIVac European consortium EU-FP7. A. Six and HPP contribution was partially sponsored by the LabEx Transimmunom (ANR-11-IDEX-0004-02). S. Cardinaud was supported by ANRS and Sidaction. A. Urrutia was supported by Sidaction. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.