IgA reactivity in patients with intestinal or hepatic amebiasis.

The antigens of E. histolytica recognized by IgA antibodies in sera from patients with either amebic liver abscess or intestinal amebiasis, as well as saliva from the latter, were determined in immunoblots of whole native trophozoite proteins. Results show that sera of patients with amebic liver abscess reacted mainly with amebic proteins of more than 200 kDa, whereas those of individuals with intestinal amebiasis recognized a protein of 145 kDa. The saliva of the latter detected a protein of 210 kDa which is not always seen when using the sera of patients with intestinal or hepatic amebiasis.