Immunological detection of human bladder carcinoma.

A rabbit antiserum (RABCa) to membrane antigenic extracts of human bladder carcinomas was produced. RABCa failed to detect bladder cancer-specific antigens in gel diffusion reaction against antigenic extracts of bladder carcinoma and normal bladder mucosa. However, RABCa showed higher complement fixation activity against urines from bladder cancer patients compared with normal urines. The micro-complement fixation (CF) assay (108 patients) was positive in 17 of 27 bladder cancer patients (62.9%) compared to only 1 of 29 normals (3.4%). However, 10 of 11 patients with urinary infections also were positive. A micro-Ouchterlony agar gel diffusion assay was also used to study urine samples (118 patients). RABCa produced separate precipitin bands against 20 of 30 bladder cancer urines (66.7%) while only 1 of 24 normal urines gave these bands (4.2%). Again, infected urines were positive (9 of 11). Additionally, urine from patients with benign urological disease was often positive in CF (11 of 41) and Ouchterlony (15 of 43) assays. RABCa serum was absorbed with normal bladder mucosa membrane extracts either once (1X) or three times (3X) to increase the specificity of the Ouchterlong gel diffusion assay. Using RABCa (1X) the per cent of positive bladder cancer urines and normals decreased only slightly, while the number of positive reactions against benign urological disease urines dramatically decreased (17.9%). RABCa (3X) further reduced the per cent of positive reactions with benign urological disease urines (10.3%), greatly reduced the reactivity with infected urines (60.0%), and gave no positive reactions with normal urines, without significantly decreasing the abiltiy to detect bladder carcinoma (51.9%). Although RABCa was 100% effective in detecting high grade (III) bladder tumors, almost two-thirds of all transitional cell papilloma urines were also positive. The nature of the material detected in bladder cancer and infected urines by RABCa is probably a product of in vivo inflammation. It does not appear to be part of the bacterial cell membrane or a bacterial metabolite. CEA (up to 10 ng/ml) did not produce positive precipitin bands with RABCa. Sephadex G-100 fractionation of urines suggests that RABCa reacts in the CF and Ouchterlony assays with a component or urine which has a molecular weight greater than 100,000-200,000 M.W. In summary, an antiserum has been prepared which may be used in micro-complement fixation and micro-Ouchterlony agar gel diffusion assays for immunological screening in the early detection of clinical disease, especially bladder cancer and urinary infection.