STIMULATING ACTION OF MULTIPLE VIRULENCE FACTORS PRODUCED BY Vibrio cholerae non-O1

已知除O1型血清型（非O1型霍乱弧菌）以外的霍乱弧菌菌株可引起腹泻。与非0型霍乱弧菌相关的肠胃炎表现出各种临床症状，如黏液和带血腹泻、呕吐、恶心、发烧、腹痛以及与0型霍乱弧菌引起的霍乱相似的水样腹泻。自1992年以来，新型血清群O139霍乱弧菌在印度或孟加拉国引起流行。O139引起的严重临床症状与O1型霍乱弧菌引起的霍乱无法区分。这些不同的症状可能是由霍乱弧菌产生多种毒素引起的，包括霍乱毒素（CT）样毒素、耐热性直接溶血素（TDH）样毒素（NAG-rTDH）、热稳定性（ST）样毒素（NAG-ST）、El - Tor溶血素样毒素和血凝素/蛋白酶（Vc-HA/P）。我们已经提纯了毒素，并分析了每种毒素的生物活性。由于多种毒力因子在体内实际上似乎是相互影响的，我们分析了多种致病因子的刺激作用以及O139产生的毒力因子的鉴定。在这一时期我们得到的结果是：(1)我们用限制性片段模式发现了O139染色体基因中ctchi基因的不稳定性；(2)我们纯化了O139产生的蛋白酶，并将其与霍乱弧菌O1的蛋白酶进行了比较，发现这两种蛋白酶无法区分。(3)在攻毒前对家兔回肠袢进行蛋白酶处理，发现E1 Tor溶血素样毒素可被霍乱弧菌非o1产生的蛋白酶加工，从而增加其在体液中的蓄积活性。(4)我们在哺乳小鼠实验中观察到ct样肠毒素与NAG-ST、NAG-ST和E1 Tor溶血素样毒素之间存在刺激作用。

Vibrio cholerae strains other than serovar O1 (non-O1 V.cholerae) have been known to cause diarrhea. Gastroenteritis associated with V.cholerae non-O1 shows vareous clinical symptomes, such as mucous and bloody diarrhea, vomiting, nausea, fever, abdominal pain as well as watery diarrhea similar to cholera due to V.cholerae O1. Novel serogroup V.cholerae O139 have caused epidemics in India or Bangladesh since 1992. Severe clinical sympotme due to O139 were undistinguishable from cholerae due to V.cholerae O1. These various symptomes may be explained by the production of a varaiety of toxins by V.cholerae non-O1, including cholera toxin (CT) -like toxin, thermostable direct hemolysin (TDH) -like toxin (NAG-rTDH), heat-stable (ST) -like toxin (NAG-ST), El Tor hemolysin-like toxin, and hemagglutinin/protease (Vc-HA/P). We already purified toxins and analyzed biological activity of each toxins. As multiple virulence factors are seemed to affect each other in vivo actually, we analyzed stimulating action of multiple pathogenic factors as well as identification of virulence factors produced by O139.The results we have got in this periods are (1) we showed unstability of ctchi gene in chromosomal gene of O139 by using restriction fragment pattem, (2) we purified protease produced by O139 and compared to protease of V.cholerae O1, showing both proteases are undistinguishable, (3) Protease treatment of rabbit ileal loop before challenge of E1 Tor-hemolysin-like toxin showed increased fluid accumulation activity because E1 Tor hemolysin-like toxin is known to be processed by protease produced by V.cholerae non-O1 and results in increasing of activity, (4) we observed stimulating action between ct-like enterotoxinand NAG-ST,NAG-ST and E1 Tor hemolysin-like toxin in suckling mouse assay.