Antigens of Entamoeba histolytica recognized by immune sera from liver abscess patients.

Immune sera from 11 patients cured of amebic liver abscess was used to identify antigens of Entamoeba histolytica. Strain HM1-IMSS, among the most virulent in axenic culture, was used. The 37 and 90 Kd antigens were surface glycoproteins as indicated by lactoperoxidase iodination and by Concanavalin A blotting; the 59 Kd antigen was a mannose containing glycoprotein that did not appear to be on the cell surface. Western blots of 11 different immune sera revealed specific binding of immune IgG to 9 amebic proteins. Most frequently recognized proteins were of molecular weight 37, 59, and 90 Kd. The immunoblot pattern in 5 patients was unchanged for up to 30 months post-treatment for liver abscess.