[Monoclonal antibody to desmosome associated 34 kD protein and immunohistochemical study in relation to the malignancy of transitional cell carcinomas of urinary bladder].

A mouse monoclonal IgG1 antibody (B-11) that recognized desmosomes in some human tissues was isolated and characterized. By Western blotting, B-11 recognized 34 kD protein only in squamous and transitional epithelium. By avidin-biotin complex (ABC) and immunofluorescence method, B-11 was reactive to squamous and transitional epithelium, but was not reactive to simple columnar epithelium from stomach and colon, simple cuboidal epithelium from urinary tubule and thyroid, and pseudostratified ciliated epithelium from trachea and ductus epididymidis. ABC method of B-11 was performed in 47 patients with transitional cell carcinoma of bladder. The higher positive staining was observed in well differentiated (83% in Grade (G) 1, 73% in G2 and 20% in G3), superficial (76% in non-invasive and 20% in invasive) and expansive growth (68% in Infiltration (INF) alpha, 24% in IFN beta and 18% in IFN gamma) carcinomas. 34 kD protein recognized by a new monoclonal antibody (B-11) is a new cell-type-specific desmosomal component which relates to the histological grade, stage and invasive manner of the transitional cell carcinoma of bladder. The transitional cell carcinoma of bladder obtained by operation or surgical biopsy from 47 patients was stained by ABC method using B-11.