Altered antigen presentation in mice lacking H2-O

Immunity. 1998 Feb;8(2):233-43. doi: 10.1016/s1074-7613(00)80475-6.


HLA-DM catalyzes the release of MHC class II-associated invariant chain-derived peptides (CLIP) from class II molecules. Recent evidence has suggested that HLA-DO is a negative regulator of HLA-DM in B cells, but the physiological function of HLA-DO remains unclear. Analysis of antigen presentation by B cells from mice lacking H2-O (the mouse equivalent of HLA-DO), together with biochemical analysis using purified HLA-DO and HLA-DM molecules, suggests that HLA-DO/H2-O influences the peptide loading of class II molecules by limiting the pH range in which HLA-DM is active. This effect may serve to decrease the presentation of antigens internalized by fluid-phase endocytosis, thus concentrating the B cell-mediated antigen presentation to antigens internalized by membrane immunoglobulin.

MeSH terms

  • Animals
  • Antigen Presentation*
  • Antigen-Presenting Cells / immunology*
  • Antigens, Differentiation, B-Lymphocyte / analysis
  • B-Lymphocytes / immunology*
  • Fluorescent Antibody Technique
  • Gene Targeting
  • HLA-D Antigens / genetics
  • HLA-D Antigens / immunology*
  • Histocompatibility Antigens Class II / analysis
  • Hydrogen-Ion Concentration
  • Immunoglobulin G / blood
  • Lymph Nodes / cytology
  • Lymph Nodes / immunology
  • Mice
  • Mice, Mutant Strains
  • Peptides / immunology
  • Precipitin Tests
  • Spleen / cytology
  • Spleen / immunology


  • Antigens, Differentiation, B-Lymphocyte
  • H-2O antigen
  • H2-M antigens
  • HLA-D Antigens
  • HLA-DM antigens
  • HLA-DO antigens
  • Histocompatibility Antigens Class II
  • Immunoglobulin G
  • Peptides
  • invariant chain