Hoste H, Nano J L, Mallet S, Huby F, Fournel S, Rampal P
INRA, Station de Pathologie Aviaire et de Parasitologie, C.R. de Tours, Nouzilly, France.
Epithelial Cell Biol. 1995;4(2):87-92.
The presence of the nematode parasite Trichostrongylus colubriformis in the small intestine is associated with an increase in epithelial renewal. To assess the possible role of excretory/secretory products from the worm on cell proliferation, adult Trichostrongylus colubriformis were incubated in vitro in Dulbecco's Modified Eagle's Medium for 24 h and the conditioned medium was added to the culture medium of the transformed epithelial cell line HT29-D4. A stimulation of the HT29-D4 cell growth was ascertained at concentrations of 0.25-1.0 micrograms protein/ml using counts of cell numbers, the MTT method and incorporation of tritiated thymidine. An increased incorporation of tritiated thymidine was also observed with the excretory/secretory products from T. colubriformis fourth stage larvae at 1.0 microgram/ml. Dialysis of the medium conditioned by the worms indicated that the molecular weight of the factor is greater than 8000 Daltons in size. Heat treatment, acid hydrolysis and precipitation by trichloracetic acid of the conditioned medium resulted in the disappearance of the proliferative effect while treatment with trypsin partially depleted the stimulative activity. These results suggest that T. colubriformis produce some protein factor which could increase the epithelial regeneration in the host small intestine.
小肠中存在的线虫寄生虫蛇形毛圆线虫与上皮更新增加有关。为了评估该蠕虫的排泄/分泌产物对细胞增殖的可能作用，将成年蛇形毛圆线虫在杜氏改良伊格尔培养基中体外培养24小时，然后将条件培养基添加到转化上皮细胞系HT29-D4的培养基中。使用细胞计数、MTT法和氚标记胸腺嘧啶核苷掺入法，在蛋白质浓度为0.25 - 1.0微克/毫升时确定了对HT29-D4细胞生长的刺激作用。在1.0微克/毫升时，还观察到蛇形毛圆线虫第四期幼虫的排泄/分泌产物使氚标记胸腺嘧啶核苷掺入增加。对蠕虫条件培养基进行透析表明，该因子的分子量大于8000道尔顿。对条件培养基进行热处理、酸水解和三氯乙酸沉淀导致增殖效应消失，而用胰蛋白酶处理则部分耗尽了刺激活性。这些结果表明，蛇形毛圆线虫产生了一些蛋白质因子，这些因子可能会增加宿主小肠中的上皮再生。
