Low levels of SIV-specific CD8+ T cells in germinal centers characterizes acute SIV infection

PLoS Pathog. 2019 Mar 21;15(3):e1007311. doi: 10.1371/journal.ppat.1007311. eCollection 2019 Mar.

Abstract

CD8+ T cells play an important role in controlling of HIV and SIV infections. However, these cells are largely excluded from B cell follicles where HIV and SIV producing cells concentrate during chronic infection. It is not known, however, if antigen-specific CD8+ T cells are excluded gradually as pathogenesis progresses from early to chronic phase, or this phenomenon occurs from the beginning infection. In this study we determined that SIV-specific CD8+ T cells were largely excluded from follicles during early infection, we also found that within follicles, they were entirely absent in 60% of the germinal centers (GCs) examined. Furthermore, levels of SIV-specific CD8+ T cells in follicular but not extrafollicular areas significantly correlated inversely with levels of viral RNA+ cells. In addition, subsets of follicular SIV-specific CD8+ T cells were activated and proliferating and expressed the cytolytic protein perforin. These studies suggest that a paucity of SIV-specific CD8+ T cells in follicles and complete absence within GCs during early infection may set the stage for the establishment of persistent chronic infection.

Publication types

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

MeSH terms

  • Acute Disease
  • Animals
  • B-Lymphocytes / physiology
  • CD8-Positive T-Lymphocytes / metabolism
  • CD8-Positive T-Lymphocytes / physiology*
  • Germinal Center / immunology
  • Germinal Center / physiology*
  • Macaca mulatta
  • Simian Acquired Immunodeficiency Syndrome / immunology*
  • Simian Acquired Immunodeficiency Syndrome / physiopathology
  • Simian Immunodeficiency Virus / immunology
  • Viral Load / immunology
  • Virus Replication