PHENOTYPIC AND PATHOGENIC CHARACTERIZATION OF BLASTOCYSTIS ISOLATES FROM EGYPTIAN PATIENTS WITH COLORECTAL CARCINOMA

Abstract

Blastocystis spp., a group of ubiquitous enteric protistan parasites with extensive genetic diversities, infects humans and many other animals. Recent studies have speculated a possible correlation between Blastocystis sp. and CRC with many conflicting reports on the question of pathogenicity of different subtypes of Blastocystis. The parasite's antigen extracted from symptomatic isolates is more pathogenic than that from asymptomatic ones causing a more extensive inflammatory reaction as well as more enhanced proliferation of cancer cells in vitro in the colorectal carcinoma HT116 cells. Moreover, the parasites caused enhancement of drug-induced carcinogenesis in experimentally infected animals. The aim of the present work was to investigate the phenotypic characters and pathogenic effects of human-derived Blastocystis isolates from early diagnosed colorectal carcinoma patients before chemotherapy intake and from Blastocystis sp. carriers apparently without colorectal carcinoma both symptomatic and asymptomatic