The classical and regulatory functions of C1q in immunity and autoimmunity.
A classical function of C1q is to bind immune complexes and initiate complement activation producing membrane lytic complexes, opsonins and anaphylatoxins. This classical pathway of complement activation is also elicited when C1q binds some other ligands. Besides complement activation, C1q also regulates cell differentiation, adhesion, migration, activation and survival. C1q deficiency is associated with autoimmunity as well as increased susceptibility to infections. In this article, we discuss the basic properties of C1q, its expression, and classical and regulatory functions.
Lu
Jin Hua
JH
Department of Microbiology, Yong Loo Lin School of Medicine and 2NUS Immunology Program, National University of Singapore, Blk MD4, 5 Science Drive 2, Singapore 117597. miclujh@nus.edu.sg
Teh
Boon King
BK
Wang
Lin da
Ld
Wang
Yi Nan
YN
Tan
Yen Seah
YS
Lai
Min Chern
MC
Reid
Kenneth B M
KB
D000818:Animals; D017951:Antigen Presentation; D000936:Antigen-Antibody Complex / Q000378:metabolism; D017209:Apoptosis; D015551:Autoimmunity; D002097:C-Reactive Protein / Q000276:immunology / Q000378:metabolism; D002454:Cell Differentiation; D003167:Complement Activation; D015922:Complement C1q / Q000172:deficiency / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D003171:Complement Pathway, Classical; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007107:Immune System / Q000166:cytology / Q000276:immunology; D008264:Macrophages / Q000276:immunology* / Q000378:metabolism; D010587:Phagocytosis; D011951:Receptors, Complement / Q000276:immunology / Q000378:metabolism
D000936:Antigen-Antibody Complex; D011951:Receptors, Complement; D015922:Complement C1q; D002097:C-Reactive Protein