転移型ヒト口腔扁平上皮癌株細胞HSC-3, LMF4およびLMF5の発現する細胞表面分子に関する研究
1994 年 61 巻 4 号 p. 527-541
詳細
1994 年 61 巻 4 号 p. 527-541
Production and characterization of hemidesmosome-specific mouse monoclonal antibodies 3A1 and 8A12 raised against the oral Squamous carcinoma line cells were previously reported. In this study, further investigations were carried out to characterize these antigens using those cells.
Immunoaffinity-purified 3A1 antigen was identified as a 180kD glycoprotein [205kD under reduced conditions] . Acetate membrane electrophoresis of disaccharides originating from this antigen digested by chondroitinase ABC showed that this protein was associated with hyaluronate.
Immunoprecipitates by 3A1 and 8A 12 antibodies were composed of two bands: 180kD and 140kD [205kD and 125kD by reduction], and were similar to integrin α6β4 precipitated by monoclonal anti-α6 subunit antibody. Immunoprecipitation-Western Blot analysis showed that the 140kD [125kD] protein precipitated by 3A1 and 8A12 was α6 subunit and that the 180kD [205kD] β4 subunit. After the α6 subunit was immunodepleted, only the 180kD [205kD] band was immunoprecipitated by 3A1 or 8A12. Both 3A1 and 8A12 blocked the adhesion of LMF5 cells to laminin.
These data indicated that 3A1 and 8A12 recognized integrin β4 subunit and that integrin α6β4 functioned as a laminin receptor on these cells. It was suggested that hyaluronan detected in the 3A1 antigen was associated with two putative hyaluronan-binding motifs in the extracel-lular domain of the integrin β4 subunit.
