Saccharomyces boulardii protease inhibits the effects of Clostridium difficile toxins A and B in human colonic mucosa
Saccharomyces boulardii protease inhibits the effects of Clostridium difficile toxins A and B in human colonic mucosa
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DOI：
10.1128/iai.67.1.302-307.1999
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发表时间：
1999-01-01
影响因子：
3.1
通讯作者：
Pothoulakis, C
中科院分区：
文献类型：
--
作者：
Castagliuolo, I;Riegler, MF;Pothoulakis, C
布拉酵母菌是一种非致病性酵母菌，用于治疗艰难梭菌腹泻和结肠炎。我们报道了S.布拉地抑制C.通过释放54-kDa蛋白酶抑制大鼠中的艰难梭菌毒素A肠炎，所述蛋白酶抑制毒素A分子及其刷状缘膜（BBM）受体（I，Castagliuolo，J.T.拉蒙，S. T. Nikulasson，和C. Pothoulakis，Infect. Immun，63：5225-5232，1996）。本研究的目的是进一步评估S.，布拉氏蛋白酶对C.艰难梭菌毒素A肠炎的大鼠回肠，并确定它是否保护人类结肠粘膜从艰难梭菌毒素，一个多克隆兔抗血清提出了针对纯化的S，布拉氏丝氨酸蛋白酶抑制73%的蛋白水解活性存在于S，布拉氏条件培养基在体外。抗蛋白酶免疫球蛋白G（IgG）阻止布拉氏酵母菌对毒素A诱导的大鼠回肠肠分泌和粘膜对[H-3]甘露醇的通透性的作用，而对照兔IgG没有影响。抗蛋白酶IgG还阻止布拉酵母蛋白酶对毒素A和B消化的影响以及对[H-3]毒素A和[H-3]毒素B与纯化的人结肠BBM结合的影响。纯化的布拉氏酵母菌蛋白酶可逆转毒素A和毒素B对人结肠（HT-29）细胞蛋白质合成的抑制作用，并可使毒素A和毒素B引起的人结肠粘膜跨上皮阻力下降分别逆转60%和68%。布拉氏菌对艰难梭菌诱导的人类炎性腹泻的作用至少部分是由于分泌的蛋白酶对毒素A和B分子的蛋白水解消化。
Saccharomyces boulardii is a nonpathogenic yeast used in the treatment of Clostridium difficile diarrhea and colitis. We have reported that S. boulardii inhibits C. difficile toxin A enteritis in rats by releasing a 54-kDa protease which digests the toxin A molecule and its brush border membrane (BBM) receptor (I, Castagliuolo, J. T. LaMont, S. T. Nikulasson, and C. Pothoulakis, Infect. Immun, 63:5225-5232, 1996). The aim of this study was to further evaluate the role of S., boulardii protease in preventing C. difficile toxin A enteritis in rat ileum and determine whether it protects human colonic mucosa from C, difficile toxins, A polyclonal rabbit antiserum raised against purified S, boulardii serine protease inhibited by 73% the proteolytic activity present in S, boulardii conditioned medium in vitro. The anti-protease immunoglobulin G (IgG) prevented the action of S, boulardii on toxin A-induced intestinal secretion and mucosal permeability to [H-3]mannitol in rat ileal loops, while control rabbit IgG had no effect. The anti-protease IgG also prevented the effects of S, boulardii protease on digestion of toxins A and B and on binding of [H-3] toxin A and [H-3] toxin B to purified human colonic BBM. Purified S, boulardii protease reversed toxin A- and toxin B-induced inhibition of protein synthesis in human colonic (HT-29) cells, Furthermore, toxin A- and B-induced drops in transepithelial resistance in human colonic mucosa mounted in Ussing chambers were reversed by 60 and 68%, respectively, by preexposing the toxins to S, boulardii protease, We conclude that the protective effects of S. boulardii on C, difficile-induced inflammatory diarrhea in humans are due, at least in part, to proteolytic digestion of toxin A and B molecules by a secreted protease.