الفهرس | Only 14 pages are availabe for public view |
Abstract Previous studies had related Blastocystis sp. to cancer colon, as Blastocystis sp. antigen facilitates the proliferation of cancer cells in vitro and the organisms caused enhancement of drug-induced carcinogenesis in vivo. The present work aimed to investigate the phenotypic and pathogenic characters and pathogenic effects of human-derived Blastocystis isolates from patients with colorectal carcinoma and from carriers without colorectal carcinoma (CRC) both symptomatic and asymptomatic. Nineteen Blastocystis sp. isolates were recruited from CRC patients, and apparent Non-CRC symptomatic and asymptomatic carriers. For each isolate the following was done: growth kinetics study and MTZ-sensitivity assay in LE medium, examination of surface ultrastructure of organisms under SEM, analysis of protein profile and zymography by SDS-page. Experimental blastocystosis have been induced in mice to examine histopathological sections of large intestine for pathogenic effects of different isolates Statistical significant differences existed between CRC and Non-CRC isolates as regards the surface ultrastructure, showing a coarse, intensely folded rough surface of CRC isolates, in contrast to, slightly rough and smooth surface of symptomatic and asymptomatic isolates, respectively, from Non-CRC carriers. A significant presence of two protein bands of 230 and 32 kDa could differentiate between CRC and Non-CRC isolates by SDS-page protein analysis. Significant differences in invasive proliferative pathogenic effects were recorded in histopathological sections of large intestine of mice infected by isolates from CRC patients and isolates from Non-CRC carriers. Zymography showed statistical non-significant increased number of protease bands in CRC isolates than Non-CRC isolates. MTZ-sensitivity was nearly similar for CRC and Non-CRC asymptomatic isolates, both are significantly higher than in symptomatic isolates. In vitro growth kinetics of CRC and Non-CRC symptomatic isolates were nearly similar with higher peaks than the slower growing Non-CRC-asymptomatic isolates. In conclusion, phenotypic and pathogenic differentiating characters exist between CRC and Non-CRC Blastocystis isolates. |