Complement regulation of T cell immunity

Immunol Res. 2012 Dec;54(1-3):247-53. doi: 10.1007/s12026-012-8327-1.


Results of studies published since 2002 reveal that T cells and antigen-presenting cells (APCs) produce complement proteins. The immune cell-derived, alternative pathway complement components activate spontaneously, yielding local, but not systemic, production of C3a and C5a. These anaphylatoxins bind to their respective G-protein-coupled receptors, C3aR and C5aR, expressed on both partners. The resultant complement-induced T cell activation and APC activation drive T cell differentiation, expansion and survival. Complement deficiency or blockade attenuates T cell-mediated autoimmunity and delays allograft rejection in mice. Increasing complement activation, achieved by genetic removal of the complement regulatory protein decay-accelerating factor, enhances murine T cell immunity and accelerates allograft rejection. The findings support the need for design and testing of complement inhibitors in humans.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Adaptive Immunity
  • Animals
  • Complement System Proteins / immunology*
  • Humans
  • T-Lymphocytes / immunology*


  • Complement System Proteins