Transcription Factor T-bet in B Cells Modulates Germinal Center Polarization and Antibody Affinity Maturation in Response to Malaria

Cell Rep. 2019 Nov 19;29(8):2257-2269.e6. doi: 10.1016/j.celrep.2019.10.087.

Abstract

Despite the key role that antibodies play in protection, the cellular processes mediating the acquisition of humoral immunity against malaria are not fully understood. Using an infection model of severe malaria, we find that germinal center (GC) B cells upregulate the transcription factor T-bet during infection. Molecular and cellular analyses reveal that T-bet in B cells is required not only for IgG2c switching but also favors commitment of B cells to the dark zone of the GC. T-bet was found to regulate the expression of Rgs13 and CXCR3, both of which contribute to the impaired GC polarization observed in the absence of T-bet, resulting in reduced IghV gene mutations and lower antibody avidity. These results demonstrate that T-bet modulates GC dynamics, thereby promoting the differentiation of B cells with increased affinity for antigen.

Keywords: B cells; T-bet; affinity maturation; antibodies; germinal center; malaria.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibody Affinity / genetics
  • Antibody Affinity / physiology
  • B-Lymphocytes / metabolism*
  • Germinal Center / cytology*
  • Germinal Center / metabolism*
  • Malaria / immunology
  • Malaria / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Mutation / genetics
  • RGS Proteins / genetics
  • RGS Proteins / metabolism
  • Receptors, CXCR3 / genetics
  • Receptors, CXCR3 / metabolism
  • T-Box Domain Proteins / genetics
  • T-Box Domain Proteins / metabolism*

Substances

  • RGS Proteins
  • Receptors, CXCR3
  • T-Box Domain Proteins
  • T-box transcription factor TBX21