Extrafollicular CD4+ T-B interactions are sufficient for inducing autoimmune-like chronic graft-versus-host disease

Nat Commun. 2017 Oct 17;8(1):978. doi: 10.1038/s41467-017-00880-2.

Abstract

Chronic graft-versus-host disease (cGVHD) is an autoimmune-like syndrome mediated by pathogenic CD4+ T and B cells, but the function of extrafollicular and germinal center CD4+ T and B interactions in cGVHD pathogenesis remains largely unknown. Here we show that extrafollicular CD4+ T and B interactions are sufficient for inducing cGVHD, while germinal center formation is dispensable. The pathogenesis of cGVHD is associated with the expansion of extrafollicular CD44hiCD62loPSGL-1loCD4+ (PSGL-1loCD4+) T cells. These cells express high levels of ICOS, and the blockade of ICOS/ICOSL interaction prevents their expansion and ameliorates cGVHD. Expansion of PSGL-1loCD4+ T cells is also prevented by BCL6 or Stat3 deficiency in donor CD4+ T cells, with the induction of cGVHD ameliorated by BCL6 deficiency and completely suppressed by Stat3 deficiency in donor CD4+ T cells. These results support that Stat3- and BCL6-dependent extrafollicular CD4+ T and B interactions play critical functions in the pathogenesis of cGVHD.Chronic graft-versus-host disease (cGVHD) is mediated by specific CD4 and B cells, but the relative contribution of extrafollicular and germinal centre (GC) T-B interaction is unclear. Here the authors show that the extrafollicular expansion of a specific CD4 T subset is sufficient for inducing cGVHD while GC is dispensable.

Publication types

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

MeSH terms

  • Animals
  • Autoimmune Diseases / immunology*
  • B-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / immunology*
  • Chronic Disease
  • Germinal Center / cytology
  • Germinal Center / immunology*
  • Graft vs Host Disease / genetics
  • Graft vs Host Disease / immunology*
  • Humans
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Proto-Oncogene Proteins c-bcl-6 / genetics
  • Proto-Oncogene Proteins c-bcl-6 / immunology
  • STAT3 Transcription Factor / genetics
  • STAT3 Transcription Factor / immunology
  • T-Lymphocytes, Helper-Inducer / immunology

Substances

  • Bcl6 protein, mouse
  • Proto-Oncogene Proteins c-bcl-6
  • STAT3 Transcription Factor
  • Stat3 protein, mouse