Immunologic characterization of the membrane-bound collagen in normal human fibroblasts: identification of a distinct membrane collagen.
Collagen, the major extracellular matrix protein, is also a membrane protein. Two types of collagen are detected on the normal human fibroblast membrane in culture, type I collagen and a new immunologically and chemically distinct collagen, type M (membrane) collagen. Antibodies to type M collagen elicited complement-mediated cytotoxicity, which could be blocked by pretreatment of the cells with bacterial collagenase or the antibody with type M collagen. Pretreatment of the cells with other proteolytic enzymes or the antibody with type I collagen or type III collagen had no effect on this complement-mediated cytotoxicity. Although type I collagen is the major collagen synthesized by normal human fibroblasts type M collagen may be the major cell membrane collagen and may be a major cell membrane component.
D000937:Antigen-Antibody Reactions; D002462:Cell Membrane / Q000378:metabolism; D003094:Collagen / Q000276:immunology* / Q000302:isolation & purification / Q000378:metabolism; D003601:Cytotoxicity Tests, Immunologic; D005347:Fibroblasts / Q000378:metabolism* / Q000648:ultrastructure
D003094:Collagen