Cutting edge: murine CD59a modulates antiviral CD4+ T cell activity in a complement-independent manner.
CD59 blocks formation of the membrane attack complex of complement by inhibiting binding of C9 to the C5b-8 complex. To investigate a role for CD59 in promoting T cell responses, we compared T cell activation in CD59a-deficient (Cd59a-/-) and wild-type (WT) mice after in vitro stimulation and after infection with rVV. Virus-specific CD4+ T cell responses were significantly enhanced in Cd59a-/- mice compared with WT mice. Similarly, Cd59a-/- T cells responded more vigorously to in vitro stimulation with CD3-specific Abs compared with WT mice. This effect of CD59a on T cell proliferation was found to be complement-independent. Collectively, these results demonstrate that CD59a down-modulates CD4+ T cell activity in vitro and in vivo, thereby revealing another link between complement regulators and T cell activation.
Longhi
M Paula
MP
Medical Biochemistry and Immunology, School of Medicine, Cardiff University, Wales, United Kingdom. longhimp@Cardiff.ac.uk
Sivasankar
Baalasubramanian
B
Omidvar
Nader
N
Morgan
B Paul
BP
Gallimore
Awen
A
D000818:Animals; D015153:Blotting, Western; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000821:virology*; D018957:CD59 Antigens / Q000276:immunology*; D049109:Cell Proliferation; D003165:Complement System Proteins / Q000276:immunology*; D047468:Immunoprecipitation; D008213:Lymphocyte Activation / Q000276:immunology; D008217:Lymphocytic choriomeningitis virus / Q000276:immunology; D051379:Mice; D014616:Vaccinia virus / Q000276:immunology; D014764:Viral Proteins / Q000276:immunology
D018957:CD59 Antigens; D014764:Viral Proteins; D003165:Complement System Proteins