Interleukin-10 prevents spontaneous death of germinal center B cells by induction of the bcl-2 protein

J Clin Invest. 1994 Jan;93(1):424-8. doi: 10.1172/JCI116977.

Abstract

In this study, we show that IL-10 enhances in vitro the viability of purified splenic B cells. There was a two- to threefold increase in recovery of viable cells during a 15-d culture period in the presence of IL-10. This effect was abolished by neutralizing antibodies to IL-10. The survival of large splenic B cells, which mostly represent follicular center cells, was similarly increased. The in vitro rescue from spontaneous death of the latter cells is known to involve a bcl-2-dependent pathway. We therefore investigated whether IL-10 might affect bcl-2 expression. Unseparated B cells as well as large splenic B cells displayed a strong expression of bcl-2 protein by immunofluorescence at days 2-7 of culture in the presence of IL-10. Other lymphokines such as IL-2 and IL-4 were able to trigger only a transient and faint expression of bcl-2; moreover, this effect was abolished by anti-IL-10 mAb. Inasmuch as activated B cells can produce their own IL-10, this lymphokine may play a crucial role in relieving from apoptosis those B cells that encounter their antigen in B cell follicles.

MeSH terms

  • B-Lymphocytes / drug effects*
  • B-Lymphocytes / immunology
  • B-Lymphocytes / pathology
  • Cell Death / drug effects*
  • Cell Survival / drug effects
  • Cells, Cultured
  • Flow Cytometry
  • Fluorescent Antibody Technique
  • Humans
  • Interleukin-10 / pharmacology*
  • Interleukin-2 / pharmacology
  • Kinetics
  • Lymphocyte Activation
  • Protein-Tyrosine Kinases / biosynthesis
  • Proto-Oncogene Proteins / biosynthesis*
  • Proto-Oncogene Proteins c-bcl-2
  • Purpura, Thrombocytopenic, Idiopathic / immunology
  • Recombinant Proteins / pharmacology
  • Spleen / immunology
  • Time Factors

Substances

  • Interleukin-2
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-bcl-2
  • Recombinant Proteins
  • Interleukin-10
  • Protein-Tyrosine Kinases