Закономірності первинного росту Blastocystis sp. на п’яти типах живильних середовищ

Abstract

Introduction. Blastocystis sp. is the most prevalent intestinal protozoan parasite in humans and many animals. Unfavorable colonization of Blastocystis sp. in human intestine is associated with development of various inflammatory diseases and irritable bowel syndrome (IBS), which may be accompanied by allergic reactions. Currently, microscopic, cultural (in vitro parasite cultivation), immunological and molecular genetic methods are used for Blastocystis sp. detection in stool samples. Cultural methods are characterized by a high degree of sensitivity and specificity. They are widely used in epidemiological studies to evaluate Blastocystis sp. prevalence, to determine their sensitivity to drugs, and to obtain parasite antigens. Cultural methods are also used to study blastocystosis pathogenesis and pathogen strains of various origins and their virulent potential, including the intensity of the amoeboid morphoforms formation, which microscopic methods fail to detect directly in faecal samples. A vast majority of previous studies of Blastocystis sp. in vitro growth in different media were performed using axenic and stabilized xenic cultures of parasites. The goal of this study was to determine growth regularities of Blastocystis sp. primary cultures in five types of nutrient media and to identify the most effective media for amoeboid morphoforms detection in short-term cultures of parasites. Materials and Methods. Three fresh stool specimens of IBS-D (Rome IV) patients were used as inoculum. The specimens contained ≥ 5 cells ofBlastocystis sp. observed in the field of view under light microscopy with ×400 magnification. Blastocystis sp. identification was carried out by means of microscopy of the faecal smears, which were stained by Wheatley's modification trichrome stain and by Heidenhain's ironhematoxylin stain. The inoculation dose of faecal samples homogenate (1:10 dilution in PBS pH = 7.4) was 200 μl per tube with 5 ml of liquid media Jones’s (mJones’s), RPMI-1640 (RPMI), Iscove's modified DMEM (IMDMEM), RPMI/IMDMEM (mixture of equal volumes of RPMI and IMDMEM media) and a liquid phase of the modified two-phase LE medium (mLE, modification Boeck and Drbohlav's).