Regulatory role of CD19 molecules in B-cell activation and differentiation

Cell Immunol. 1989 Feb;118(2):368-81. doi: 10.1016/0008-8749(89)90385-7.


Cluster of differentiation ([CD]) 19 antigens are B-cell-specific molecules expressed on virtually all human cells of the B-lymphocyte lineage except plasma cells. We produced a new anti-CD19 monoclonal antibody (McAb), CLB-CD19, that was used to study the role of CD19 molecules in B-cell activation. Anti-CD19 McAb induced mobilization of free intracellular calcium ([Ca2+]i) in Daudi cells, but not in normal spleen or tonsillar B cells, for which crosslinking with a second anti-mouse Ig antibody was not required. Anti-CD19 McAb inhibited B-cell proliferation induced by anti-IgM coupled to Sepharose beads. This inhibitory effect was overcome by the addition of nonmitogenic concentrations of phorbol myristate acetate. Anti-CD19 McAb did not interfere with Staphylococcus aureus- or B-cell growth factor-induced B-cell proliferation. Anti-CD19 McAb inhibited T-cell-dependent polyclonal B-cell differentiation in pokeweed mitogen-, interleukin 2-, or anti-CD3-driven culture systems. Delayed addition studies showed that once differentiation of B cells was induced, CD19 molecules lost their regulating function. Taken together, our results indicate that CD19 molecules play a regulatory role in B-cell proliferation and differentiation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Anti-Idiotypic / immunology
  • Antibodies, Monoclonal / immunology*
  • Antibody Formation
  • Antibody Specificity
  • Antigen-Presenting Cells / immunology
  • Antigens, CD19
  • Antigens, Differentiation, B-Lymphocyte / immunology*
  • Antigens, Differentiation, T-Lymphocyte / immunology
  • B-Lymphocytes / immunology*
  • CD3 Complex
  • Calcium / physiology
  • Humans
  • Immunoglobulin M / immunology
  • Interleukin-4
  • Interleukins / pharmacology
  • Lymphocyte Activation / drug effects
  • Lymphocyte Cooperation
  • Receptors, Antigen, T-Cell / immunology
  • T-Lymphocytes / immunology
  • Tetradecanoylphorbol Acetate / pharmacology


  • Antibodies, Anti-Idiotypic
  • Antibodies, Monoclonal
  • Antigens, CD19
  • Antigens, Differentiation, B-Lymphocyte
  • Antigens, Differentiation, T-Lymphocyte
  • CD3 Complex
  • Immunoglobulin M
  • Interleukins
  • Receptors, Antigen, T-Cell
  • Interleukin-4
  • Tetradecanoylphorbol Acetate
  • Calcium