Entamoeba histolytica: electron-dense granule secretion, collagenase activity and virulence are altered in the cytoskeleton mutant BG-3.

HM-1:IMSS, a pathogenic strain of Entamoeba histolytica, and its mutant BG-3, identified by resistance to cytochalasin D, were tested for their capacity to: (i) secrete electron-dense granules; (ii) adhere and digest native type I collagen gels; and (iii) produce liver abscesses in new-born hamsters. The results demonstrate that the mutant has low adherence to collagen, low electron-dense granule secretion and collagenolytic activity, and low capacity to produce liver lesions in vivo, compared with the parental strain HM1:IMSS.