The role of anaphylatoxins C3a and C5a in regulating innate and adaptive immune responses.
C3a and C5a, the small (approximately 10KDa) cleavage fragments released by complement activation, are potent mediators of inflammation. They are anaphylatoxins and act as cell activators with nanomolar affinity, exerting their functions through binding to specific receptors (C3aR and C5aR or C5L2 respectively). Recent studies suggest that locally generated complement effector molecules including C3a and C5a contribute to pathological processes in inflammatory and immunological diseases as well as adaptive immune response besides its host defence mechanism. Targeting the receptors and/or their ligands can reduce undesired inflammatory responses and tissue damage in certain pathological conditions. In this article we describe the recent developments in this important area and focus on the role of C3a/C5a in inflammatory and autoimmune diseases and in adaptive immune responses.
Peng
Qi
Q
Complement Laboratory, MRC Centre for Transplantation, King's College London, School of Medicine at Guy's Hospital, London SE1 9RT, UK.
Li
Ke
K
Sacks
Steven H
SH
Zhou
Wuding
W
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism; D001327:Autoimmune Diseases / Q000276:immunology / Q000378:metabolism; D015926:Complement C3a / Q000276:immunology / Q000378:metabolism*; D015936:Complement C5a / Q000276:immunology / Q000378:metabolism*; D003165:Complement System Proteins / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007110:Immunity, Active; D007113:Immunity, Innate; D007249:Inflammation / Q000276:immunology* / Q000378:metabolism; D011951:Receptors, Complement / Q000276:immunology / Q000378:metabolism; D015427:Reperfusion Injury / Q000276:immunology / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism
D011951:Receptors, Complement; D015926:Complement C3a; D015936:Complement C5a; D003165:Complement System Proteins