Germinal center B cells regulate their capability to present antigen by modulation of HLA-DO

J Exp Med. 2002 Apr 15;195(8):1063-9. doi: 10.1084/jem.20012059.


Peptide acquisition by MHC class II molecules is catalyzed by HLA-DM (DM). In B cells, HLA-DO (DO) inhibits or modifies the peptide exchange activity of DM. We show here that DO protein levels are modulated during B cell differentiation. Remarkably, germinal center (GC) B cells, which have low levels of DO relative to naive and memory B cells, are shown to have enhanced antigen presentation capabilities. DM protein levels also were somewhat reduced in GC B cells; however, the ratio of DM to DO in GC B cells was substantially increased, resulting in more free DM in GC B cells. We conclude that modulation of DM and DO in distinct stages of B cell differentiation represents a mechanism by which B cells regulate their capacity to function as antigen-presenting cells. Efficient antigen presentation in GC B cells would promote GC B cell-T cell interactions that are essential for B cells to survive positive selection in the GC.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Antigen Presentation / immunology*
  • Antigen-Presenting Cells / immunology
  • Antigens, Differentiation, B-Lymphocyte / immunology
  • B-Lymphocyte Subsets / immunology
  • B-Lymphocytes / immunology*
  • Cell Line
  • Down-Regulation
  • Germinal Center / immunology*
  • HLA-D Antigens / immunology*
  • HLA-DR Antigens / immunology
  • Histocompatibility Antigens Class II / immunology
  • Humans


  • Antigens, Differentiation, B-Lymphocyte
  • HLA-D Antigens
  • HLA-DM antigens
  • HLA-DO antigens
  • HLA-DR Antigens
  • Histocompatibility Antigens Class II
  • invariant chain