CAJ | 학술논문

目的探讨两株具有不同最高生长温度的葡萄孢弗隆那霉临床分离株的致病力、基因型的差异.方法将在37℃生长良好的江苏株和在36℃不生长的河南株葡萄孢弗隆那霉造成实验性感染.观察动物的发病、死亡以及各脏器受累情况.提取两临床分离株的DNA进行随机扩增多态DNA(RAPD)分析以及核糖体内转录间隔区(ITS区)扩增,并对产物测序.结果江苏株可造成免疫正常及免疫抑制小鼠的暗色丝孢霉病,前者死亡率为30%,后者死亡率65%,两组间差异有统计学意义.免疫抑制组小鼠的肺脏感染率为100%,明显高于其他脏器,差异具有统计学意义;肝脏直接镜检阳性率为64.7%,组织培养阳性率为70.5%;免疫正常组各脏器感染阳性率差异无统计学意义,肺脏阳性率为57.8%,肝脏为42.1%.免疫抑制组小鼠的肺脏感染率明显高于免疫正常组.河南株在免疫正常组和免疫抑制组均未见导致明确的感染.RAPD和ITS区测序结果显示,在ITS区的236位碱基处有一个碱基的差异(A→G).结论两株菌具有不同的基因型;葡萄孢弗隆那霉江苏株可以导致免疫抑制和免疫正常小鼠的系统性暗色丝孢霉病,前者的致死率显著高于后者,致病力与其免疫状态有关;免疫抑制状态下,肺脏是其最常受累的器官.
목적 탐토량주구유불동최고생장온도적포도포불륭나매림상분리주적치병력、기인형적차이.방법 장재37℃생장량호적강소주화재36℃불생장적하남주포도포불륭나매조성실험성감염.관찰동물적발병、사망이급각장기수루정황.제취량림상분리주적DNA진행수궤확증다태DNA(RAPD)분석이급핵당체내전록간격구(ITS구)확증,병대산물측서.결과 강소주가조성면역정상급면역억제소서적암색사포매병,전자사망솔위30%,후자사망솔65%,량조간차이유통계학의의.면역억제조소서적폐장감염솔위100%,명현고우기타장기,차이구유통계학의의;간장직접경검양성솔위64.7%,조직배양양성솔위70.5%;면역정상조각장기감염양성솔차이무통계학의의,폐장양성솔위57.8%,간장위42.1%.면역억제조소서적폐장감염솔명현고우면역정상조.하남주재면역정상조화면역억제조균미견도치명학적감염.RAPD화ITS구측서결과 현시,재ITS구적236위감기처유일개감기적차이(A→G).결론 량주균구유불동적기인형;포도포불륭나매강소주가이도치면역억제화면역정상소서적계통성암색사포매병,전자적치사솔현저고우후자,치병력여기면역상태유관;면역억제상태하,폐장시기최상수루적기관.
Objective To study the difference in pathogenicity and genotype between two isolates of Veronaeae botryosa with different temperature tolerance. Methods Two strains of Veronaeae botryose were isolated from two patients with phaeohyphomycosis in Jiangsu and Henan province respectively. Of them, the Jiangsu strain could grow well at 37 ℃, but Henan strain could not grow at 36 ℃. Eighty mice were equally classified into immunocompetent and immune-suppressed (induced by cyclophosphamide) groups to be inoculated with the two strains of Veronaeae botryosa respectively. Ten mice remained uninoculated and served as the control. The general condition, growth and organic involvement of mice were observed for 4 weeks followed by the killing of surviving mice. Homogenated tissue samples were obtained from liver, spleen, lung, kidney and brain; then, tissue culture, direct microscopy and pathological examination were performed. Genomie DNA was extracted from tissue samples and subjected to random amplified polymor-phic DNA (RAPD) analysis. PCR was performed to amplify the intemal transcribed spacer (ITS) of rDNA followed by sequencing Results Systemic phaeohyphomycosis was induced in both immunocompetent and immune-suppressed mice by the Jiangsu strain of Veronaeae botryose; the mortality was 30% in immune-competent mice and 65% in immune-suppressed mice with statistical significance between the two groups. In immune-suppressed mice inoculated with the Jiangsu strain, the infection rate was 100% in the lung,signifi-cantly higher than in other organs; on direct microscopy the infection rate reached 64.7% in the liver, and 70.5% on tissue culture. There was no significant difference in the infection rate among these organs in immunocompetent mice inoculated with the Jiangsu strain, with the infection rate being 57.8% in the lung and 42.1% in the liver. Increased infection rate was observed in the lung of immune-suppressed mice com-pared with immunocompetent mice (P < 0.05). No definite infection was seen in immunoeompetent or immune-suppressed mice innoculated with the Henan strain. RAPD analysis and sequencing revealed that there was a base variation (A/G) at position 236 of ITS gene between the two strains. Conclusions The two strains of Veronaeae botryosa have different genotypes. Systemic phaeohyphomycosis can be caused in immunocompetent and immuno-suppressed mice by the Veronaeae botryosa isolate from Jiangsu Province; the mortality was higher in immuno-suppressed mice than in immunocompetent mice. The pathogenicity of Veronaeae botryose is associated with the immune status of hosts. In immuno-suppressed mice, lung is the organ most susceptible to infection by Veronaeae botryosa.