title: Detachment of cell surface-bound anticarcinoembryonic antigen immune complexes by phospholipase C.
abstract: CEA as well as normal cross-reacting antigens (NCA) are fixed to the cell membrane via phosphatidylinositol (PI). To find out whether these antigens are internalized after antibody contact, acid pH desorption was compared to phospholipase C (PLC)-mediated cleavage of the antigen anchor. With the former procedure, marked differences in the desorbability of individual MAbs were noted, while PLC was able to cleave off surface-bound immune complexes irrespective of the MAb involved. From this it is concluded that internalization of MAb complexes of CEA/NCA, if occurring at all, is a low efficiency process.
authors.affiliation: Institute of Radiology, German Cancer Research Center, Heidelberg.
authors.forename: S
authors.initials: S
authors.lastname: Matzku
authors.forename: J P
authors.initials: JP
authors.lastname: Mach
authors.forename: F
authors.initials: F
authors.lastname: Buchegger
authors.forename: G
authors.initials: G
authors.lastname: Moldenhauer
authors.forename: M
authors.initials: M
authors.lastname: Stadler
authors.forename: H
authors.initials: H
authors.lastname: Kalthoff
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology; D000936:Antigen-Antibody Complex / Q000378:metabolism*; D002272:Carcinoembryonic Antigen / Q000276:immunology*; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010716:Phosphatidylinositols / Q000378:metabolism; D014407:Tumor Cells, Cultured; D010738:Type C Phospholipases / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D002272:Carcinoembryonic Antigen; D010716:Phosphatidylinositols; D010738:Type C Phospholipases