Isoenzyme pattern of clones of Entamoeba histolytica

The isoenzyme pattern of clones of E. histolytica isolated from symptomatic and asymptomatic patients of amoebiasis were determined by starch gel electrophoresis. Ten parent cultures (uncloned), 5 from symptomatic and 5 from asymptomatic patients were isolated and established in Robinsons medium as xenic cultures. A total of 100 clones were isolated from parent cultures but only 65 could be established. Starch gel electrophoresis was carried out on the uncloned and cloned cultures. The analysis showed that the 5 uncloned culture from symptomatic patients had 4 isolates with pathogenic zymodeme and 1 isolate with non-pathogenic zymodeme pattern. The presence of beta band and absence of alpha band for phosphoglucomutase (PGM) and a fast moving Hexokinase (HK) band were taken as markers of pathogenicity. The 5 cloned cultures from asymptomatic patients had three isolates with pathogenic and 2 with non-pathogenic pattern. The cloned isolates from symptomatic patients (35) had 20 pathogenic zymodemes and asymptomatic patients (30) had 15 pathogenic zymodemes. Non-pathogenic zymodeme obtained in the present study were I, IV, V, X and XIII and the pathogenic zymodemes obtained were II and XIV. The data of the study indicated that (i) asymptomatic patients also harbour pathogenic zymodemes; and (ii) zymodeme II also coexsist with zymodeme XIV in the Indian population.