Assay of epithelial membrane antigen (EMA) in human serum by ELISA.

An enzyme linked immuno sorbent assay (ELISA) for an epithelial membrane antigen (EMA) was described. Possible cross reactions with various antigens were investigated. In sera, EMA has been found in all the subjects studied. In normal population, levels were in the range of 500 ng/ml +/- 125 (S.D.) A significant increase was observed at the end of pregnancy and during lactation. A large number of patients suffering various benign and cancerous diseases were studied. The elevated levels found in breast and pulmonary pathology indicated that this assay could be useful in the follow-up of patients suffering from these diseases.