title: Regulation of mast cell activation by complement-derived peptides.
abstract: It is known for more than 25 years that the complement-derived anaphylatoxic peptides, C3a, C4a and C5a are potent activators of basophils and certain types of mast cells. Although tissue distribution of receptors for C3a and C5a well exceeds myeloid cells, apparently they are not expressed on mucosal type mast cells, consequently these cells are not activated by C3a and C5a. Our results do however demonstrate that C3a and peptides related to this complement activation product are able to inhibit FcRI-clustering induced activation of mucosal type mast cells-such as RBL-2H3 cells and bone-marrow derived mast cells. Based on the current results we propose the presence of separate "activator" and "inhibitor" sequence motifs in C3a which are in balance under physiologic conditions.
authors.affiliation: Department of Immunology, Research Group of the Hungarian Academy of Sciences, Eötvös Loránd University, Pázmány Péter s. 1/C, H-1117 Budapest, Hungary. anna.erdei@freemail.hu
authors.forename: Anna
authors.initials: A
authors.lastname: Erdei
authors.forename: Márton
authors.initials: M
authors.lastname: Andrásfalvy
authors.forename: Hajna
authors.initials: H
authors.lastname: Péterfy
authors.forename: Gábor
authors.initials: G
authors.lastname: Tóth
authors.forename: Israel
authors.initials: I
authors.lastname: Pecht
mesh_terms: D000818:Animals; D015926:Complement C3a / Q000276:immunology / Q000502:physiology; D003165:Complement System Proteins / Q000276:immunology* / Q000502:physiology; D006801:Humans; D008407:Mast Cells / Q000276:immunology* / Q000502:physiology; D010446:Peptide Fragments / Q000276:immunology* / Q000502:physiology
chemical_list: D010446:Peptide Fragments; D015926:Complement C3a; D003165:Complement System Proteins