title: Complement in basic processes of the cell.
abstract: The complement system is reemerging in the last few years not only as key element of innate immunity against pathogens, but also as a main regulator of local adaptive responses, affecting dendritic cells as well as T and B lymphocytes. We review data showing that leucocytes are capable of significant autocrine synthesis of complement proteins, and express a large range of complement receptors, which in turn regulate their differentiation and effector functions while cross talking with other innate receptors such as Toll-like receptors. Other unconventional roles of complement proteins are reviewed, including their impact in non-leukocytes and their intracellular cleavage by vesicular proteases, which generate critical cues required for T cell function. Thus, leucocytes are very much aware of complement-derived information, both extracellular and intracellular, to elaborate their responses, offering rich avenues for therapeutic intervention and new hypothesis for conserved major histocompatibility complex complotypes.
authors.affiliation: Department of Immunology, Complutense University School of Medicine and Hospital 12 de Octubre Health Research Institute, Madrid, Spain. Electronic address: ajreinoso@med.ucm.es.
authors.forename: Anaïs
authors.initials: A
authors.lastname: Jiménez-Reinoso
authors.affiliation: Department of Immunology, Complutense University School of Medicine and Hospital 12 de Octubre Health Research Institute, Madrid, Spain. Electronic address: anavictoriamarin@ucm.es.
authors.forename: Ana V
authors.initials: AV
authors.lastname: Marin
authors.affiliation: Department of Immunology, Complutense University School of Medicine and Hospital 12 de Octubre Health Research Institute, Madrid, Spain. Electronic address: regueiro@med.ucm.es.
authors.forename: José R
authors.initials: JR
authors.lastname: Regueiro
mesh_terms: D000818:Animals; D003167:Complement Activation / Q000276:immunology*; D003165:Complement System Proteins / Q000276:immunology*; D006801:Humans
chemical_list: D003165:Complement System Proteins
keywords: B lymphocyte; Complement; Complotype; Dendritic cell; T lymphocyte