Comparison of some methods for the detection of antigen-antibody reactions in amoebiasis

The indirect hemagglutination test (IHA) and counterimmuno-electrophoresis (CIE) were used to test for antibodies to Entamoeba histolytica in human sera using antigens from axenic cultures of the HK9 strain. Correlation between the test was excellent with most sera from patients with amoebiasis demonstrating precipitin lines by CIE at IHA titers considered diagnostically positive, larger than or equal to 1:128. Precipitin reactions with positive sera were also compared by CIE, immunoelectrophoresis (IEP) and two-dimensional electrophoresis is (2D-IEP). The greatest number of antigen-antibody components were demonstrated by 2D-IEP. Further studies utilizing 2D-IEP should be of value in the antigenic analysis of E. histolytica.