Analysis of soluble Entamoeba histolytica antigen using enzyme-L inked electroimmunotransfer blots

Soluble antigens of ten strains of E. histolytica were studied by sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked electroimmunotransfer blots (EITB). No relations of immune replicas to virulence, geographical origin and method of cultivation (xenic or axenic culture) were found. Antigens of all ten strains tested precipitated with anti-E. histolytica human serum in the area of 30-43 kD. Antigen of HK-9 strain created in this area a characteristic pattern with all sera containing the specific anti-E. histolytica antibodies and, therefore, EITB can be used for excluding false positive results in ELISA.