title: Complement receptors regulate lipopolysaccharide-induced T-cell stimulation.
abstract: Complement receptors type 1 and 2 (CR1 (CD35)/CR2 (CD21)) are known to enhance the adaptive immune response. In mice, CR1/CR2 are expressed on B cells, follicular dendritic cells, and activated granulocytes. Recently, we showed that a subset of CD44high and CD62Llow T cells also expresses CR1 and CR2. We now report that CR1/CR2 are detectable on both CD4+ and CD8+ subsets of T cells. Lipopolysaccharide (LPS) from Gram-negative bacteria causes polyclonal activation of B cells and stimulation of macrophages and other antigen-presenting cells. We further demonstrate that LPS induced marked up-regulation of CD25 and CD69 on T cells from CR1/CR2 sufficient (Cr+/+), but significantly lower up-regulation on T cells from CR1/CR2 deficient (Cr-/-) mice. These findings point to a novel mechanism by which CR1/CR2 modulates the activation of T cells by LPS.
authors.affiliation: Department of Internal Medicine III--Cardiology, University of Heidelberg, Heidelberg, Germany. ziya_kaya@med.uni-heidelberg.de
authors.forename: Ziya
authors.initials: Z
authors.lastname: Kaya
authors.forename: Theresa
authors.initials: T
authors.lastname: Tretter
authors.forename: Jens
authors.initials: J
authors.lastname: Schlichting
authors.forename: Florian
authors.initials: F
authors.lastname: Leuschner
authors.forename: Marina
authors.initials: M
authors.lastname: Afanasyeva
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Katus
authors.forename: Noel R
authors.initials: NR
authors.lastname: Rose
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002469:Cell Separation; D002478:Cells, Cultured; D005434:Flow Cytometry; D037181:Lectins, C-Type; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D008264:Macrophages / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011951:Receptors, Complement / Q000276:immunology*; D017463:Receptors, Complement 3b / Q000276:immunology; D017464:Receptors, Complement 3d / Q000276:immunology; D015375:Receptors, Interleukin-2 / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D037181:Lectins, C-Type; D008070:Lipopolysaccharides; D011951:Receptors, Complement; D017463:Receptors, Complement 3b; D017464:Receptors, Complement 3d; D015375:Receptors, Interleukin-2; D000099192:CD69 Antigens