Comparative study of carcinoembryonic antigen in rheumatoid synovium, tumour, and normal adult lung.

Abstract

Material reacting like carcinoembryonic antigen (CEA) in the radioimmunoassay was extracted from [human] rheumatoid synovial membranes. This CEA activity was compared to that found in hepatic metastases from colorectal tumors and in normal adult lung. The antigen in the rheumatoid synovium was more sensitive to perchloric acid and was isolated with a lower weight than that derived from the tumor and lung. Immunodiffusion studies with anti-CEA indicate that the CEA-like determinants in the rheumatoid synovium have partial identity with tumor CEA and that a significant proportion of them are associated with large MW material. Production of an antiserum to these CEA-like components in the rheumatoid synovium should enable further identification of their relationship to tumor CEA and might allow a better judgement of whether they represent the expression of neoantigens in the disease.