Use of a high molecular weight Entamoeba histolytica antigen fraction in enzyme-linked immunosorbent assay and thin layer immunoassay tests.

A high molecular weight Entamoeba histolytica antigen fraction I was employed for the determination of anti-amoebic antibodies in ELISA and thin layer immunoassay (TIA) tests. A large number of human serum and immunized guinea pig serum samples were tested against this antigen. In comparison, ELISA was found more sensitive than the TIA technique. The potent antigen fraction I used in these tests was lyophilized at an optimum concentration of 1 mg/ml for obtaining uniform results.