PCR检测大鼠卡氏肺孢子虫的研究

Detection of Pneumocystis carinii in rat by PCR

目的探讨PCR技术检测大鼠卡氏肺孢子虫的应用价值。方法SD大鼠和Wistar大鼠均随机分成实验组和对照组,实验组每周两次皮下注射醋酸可的松,诱导产生卡氏肺孢子虫;8week后,收集肺组织和支气管肺泡灌洗液(BALF),用PCR技术检测卡氏肺孢子虫DNA,并与Giemsa染色法比较。结果实验组两种大鼠肺组织卡氏肺孢子虫DNA阳性率分别为9643%和100%,BALF阳性率亦分别为9643%和100%,它们之间均无显著性差异(P>005);BALF的PCR阳性检出率显著高于Giemsa病原染色法,肺组织的两种方法检出率无显著性差异。结论PCR是一种检出率较高的方法,可作为早期诊断PCP的常规方法,特别适用于BALF检测卡氏肺孢子虫DNA。

To evaluate the value of PCR for the detection of Pneumocystis carinii in rats, the present study was performed by using SD and Wistar rats, in which they were divided randomly into experimental and control groups, and the experimental group was rendered immuno suppressive by subcutaneous injections of hydrocortisone acetate twice weekly for 8 weeks. Then the lung tissues and the bronchio akveolar lavage fluid (BALF) were collected; meanwhile, the P.carinii DNA was detected by PCR and was compared with the results obtained by the examinations with Giemsa staining. The results showed that the positive rates of P.carinii DNA detection both in lung tissues and BALF of SD and Wistar rats were 93.43% and 100% respectively. The DNA detection rate by PCR in BAL was significantly higher than that obtained by the Giemsa staining; but the positive rate in lung tissues by both methods showed no significant difference. It is concluded that P.carinii DNA detection by PCR is a better method with high detection rate,and can be used for the early diagnosis of Pneumocystis carinii pneumonia (PCP), especially for the detection of P.carinii DNA in BALF.