CAJ | 학술논문

目的：通过研究肠球菌溶血素的毒力，为肠球菌的致病机制及其临床感染的诊断防治奠定基础。方法取30只清洁级 ICR小鼠，随机分为5组，每组6只，其中1～4组按10倍梯度以每只1 ml的量腹腔注射5×107 cfu／ml～5×1010 cfu／ml的 EF A7，第5组为对照组腹腔注射0.5 ml生理盐水。同样方法另取30只小鼠腹腔注射5×107 cfu／ml～5×1010 cfu／ml的 EF A7 cyl mutant，比较原始株、变异株感染小鼠的 LD50，并在感染后连续一周每天观察小鼠的死亡情况。另取7组小鼠用同一细菌浓度（5×109 cfu／ml）分别进行腹腔注射 EF A7和 EF A7 cyl mutant，分别在感染后6 h，12 h和24 h比较小鼠外周血白细胞的数量、急性期细胞因子TNF-α的浓度。结果肠球菌溶血素 EF A7 cyl mutant在小鼠腹膜炎模型中的半数致死量（LD50）比原始株肠球菌 EF A7降低了100倍以上。在相同细菌感染浓度下（5×1010 cfu／ml），EF A7 cyl mutant组和原始株 EF A7组小鼠的存活率差异有统计学意义（P＜0.05），EF A7 cyl mutant组和原始株 EF A7组6 h和12 h外周血白细胞差异有统计学意义（P＜0.05）。EF A7 cyl mutant组和原始株EF A7组腹腔注射感染小鼠6 h后腹腔积液中的炎症因子TNF-α的浓度差异有统计学意义（P＜0.05）。结论肠球菌溶血素在小鼠腹膜炎致病中起重要的作用，是肠球菌的毒力因子之一。
목적：통과연구장구균용혈소적독력，위장구균적치병궤제급기림상감염적진단방치전정기출。방법취30지청길급 ICR소서，수궤분위5조，매조6지，기중1～4조안10배제도이매지1 ml적량복강주사5×107 cfu／ml～5×1010 cfu／ml적 EF A7，제5조위대조조복강주사0.5 ml생리염수。동양방법령취30지소서복강주사5×107 cfu／ml～5×1010 cfu／ml적 EF A7 cyl mutant，비교원시주、변이주감염소서적 LD50，병재감염후련속일주매천관찰소서적사망정황。령취7조소서용동일세균농도（5×109 cfu／ml）분별진행복강주사 EF A7화 EF A7 cyl mutant，분별재감염후6 h，12 h화24 h비교소서외주혈백세포적수량、급성기세포인자TNF-α적농도。결과장구균용혈소 EF A7 cyl mutant재소서복막염모형중적반수치사량（LD50）비원시주장구균 EF A7강저료100배이상。재상동세균감염농도하（5×1010 cfu／ml），EF A7 cyl mutant조화원시주 EF A7조소서적존활솔차이유통계학의의（P＜0.05），EF A7 cyl mutant조화원시주 EF A7조6 h화12 h외주혈백세포차이유통계학의의（P＜0.05）。EF A7 cyl mutant조화원시주EF A7조복강주사감염소서6 h후복강적액중적염증인자TNF-α적농도차이유통계학의의（P＜0.05）。결론장구균용혈소재소서복막염치병중기중요적작용，시장구균적독력인자지일。
Objective The purpose of this study was to understand the pathogenic mechanisms of enterococcal hemolysin and establish the foundation to diagnose and control relevant diseases.Methods Take 30 clean grade ICR mice were randomly divided into ten groups,each 6,1 to 4 groups according to 10-fold gradient amount per 1 ml intraperitoneal injection of 5× 107 cfu/ml~5×1010 cfu/ml of EF A7,group 5 as a control group injected 0.5 ml saline,take another 30 clean grade ICR mice,intraperitoneal injection of 5×107 cfu/ml~5×1010 cfu/ml of EF A7 cyl mutant by the same measures,compared to the original strains of mice infected with mutant strain LD50,and a week after infection mortality was observed in mice daily. Another seven groups of mice with the same bacterial concentration (5×109 cfu/ml)were injected intraperitoneally EF A7 and EF A7 cyl mutant,after infection 6 h,12 h and 24 h comparing the number of leukocytes in peripheral blood of mice,re-spectively,the concentration of TNF-αin the acute phase of cytokines.Results In the mouse peritonitis models the 50% le-thal dose (LD50)of EF A7 cyl mutant was 100 times lower than enterococcus faecalis EF A7.The differences of the survival percentage of EF A7 cyl mutant groups and EF A7 groups have significance (P<0.05).As the changes in boold leukocytes numbers and the TNF-αlevel.Conclusion Cyl gene is probably a major virulence factor of Enterococcus and plays an impor-tant role in the mouse peritonitis model.