title: Relationship between xenotransplantability and cell surface properties of ascites sublines of a rat mammary adenocarcinoma.
abstract: Cell surface properties of several ascites sublines of the 13762 rat mammary adenocarcinoma were compared in an effort to understand factors important to the xenotransplantability of these tumors into C57BL/6J mice. MAT-C, MAT-C1, and MAT-cMR6-S ascites sublines were xenotransplantable; MAT-B1, MAT-C2, and MAT-MR2-S were not. All of these sublines contained a large mucin-type sialoglycoprotein (ASGP-1) as a major cell surface component. Mat-B1 and MAT-cMR6-S ASGP-1 molecules were sulfated, but MAT-C1 and MAT-MR2-S incorporated little sulfate. The major oligosaccharide of MAT-C1 ASGP-1, a disialo-oligosaccharide, was present in very low amounts in the other sublines. ASGP-1 was detected readily in the plasma of animals with MAT-C1 or MAT-MR2-S tumors, but it was not detected readily in animals with MAT-B1 or MAT-cMR6-S tumors. Thus none of these significant features of ASGP-1 that differed among the sublines correlated with xenotransplantation. However, both MAT-C1 and MAT-cMR6-S sublines had branched cell surface microvilli. Moreover, MAT-C grown in mice after xenotransplantation had extensive, branched microvilli, even though only about 10% of the population of the cells grown in the rat had them. These results suggest that the branched microvilli may provide a protective mechanism, possibly by acting as a barrier to the approach of cytotoxic cells.
mesh_terms: D000230:Adenocarcinoma / Q000032:analysis*; D000818:Animals; D001943:Breast Neoplasms / Q000032:analysis*; D002460:Cell Line; D002499:Centrifugation, Density Gradient; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D008855:Microscopy, Electron, Scanning; D051381:Rats; D011952:Receptors, Concanavalin A / Q000032:analysis; D012795:Sialoglycoproteins / Q000032:analysis / Q000097:blood; D013499:Surface Properties
chemical_list: D011952:Receptors, Concanavalin A; D012795:Sialoglycoproteins