title: Virulence of nonpathogenic zymodemes of Entamoeba histolytica isolates from asymptomatic subjects in Calcutta, India.
abstract: 1. The zymodeme and virulence of 31 Entamoeba histolytica isolates obtained from asymptomatic human subjects in Calcutta, India are described. 2. Virulence was measured by the extent of lesion diameter (mm) induced by each isolate in the liver of golden hamsters and resistance of isolates to non-immune hamster sera in vitro. 3. Two nonpathogenic zymodemes, III (N = 17) and IV (N = 14), were detected among 31 isolates by isoenzyme electrophoresis. Most of the zymodeme III isolates were moderately to highly virulent while a quarter of the zymodeme IV were invasive although with low virulence. 4. The virulence of the isolates was found to have a significant positive correlation (r = 0.96, P < 0.001) with their greater resistance to complement-mediated lysis. 5. The data suggest that the virulence of E. histolytica is probably not related to its zymodeme.
authors.affiliation: Kothari Centre of Gastroenterology, Kothari Medical Centre, Calcutta, India.
authors.forename: R M
authors.initials: RM
authors.lastname: Mukherjee
authors.forename: M
authors.initials: M
authors.lastname: Mazumdar
authors.forename: T K
authors.initials: TK
authors.lastname: Maitra
authors.forename: K N
authors.initials: KN
authors.lastname: Jalan
mesh_terms: D000818:Animals; D015941:Complement Hemolytic Activity Assay; D006224:Cricetinae; D004591:Electrophoresis, Polyacrylamide Gel; D004748:Entamoeba histolytica / Q000201:enzymology* / Q000302:isolation & purification / Q000472:pathogenicity*; D004749:Entamoebiasis / Q000469:parasitology*; D005956:Glucose-6-Phosphate Isomerase / Q000032:analysis; D006593:Hexokinase / Q000032:analysis; D006801:Humans; D007194:India; D007527:Isoenzymes / Q000032:analysis*; D008291:Malate Dehydrogenase / Q000032:analysis; D008647:Mesocricetus; D010733:Phosphoglucomutase / Q000032:analysis; D014774:Virulence / Q000502:physiology
chemical_list: D007527:Isoenzymes; D008291:Malate Dehydrogenase; C031917:malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+); D006593:Hexokinase; D005956:Glucose-6-Phosphate Isomerase; D010733:Phosphoglucomutase