The study with rapid detection for the toxins of Methicillin-resistant Staphylococcus aureus and with the action of the toxins

1. 建立了用聚合酶链反应（PCR）检测葡萄球菌肠毒素和TSST-1基因的方法。制备了5对（ent A - D和test）寡核苷酸引物，并用金黄色葡萄球菌临床分离株进行了检测。在A、B、D和试验中，PCR和免疫法的结果几乎相同。免疫法未检出肠毒素C的金黄色葡萄球菌菌株，用PCR法检测了ent C基因。术后MRSA肠炎的主要致病菌株毒性类型为A、C和test .2。然后，直接从临床标本（痰液和胃液）中提取葡萄球菌DNA，进行mec A PCR和检测。MRSA最小CFU的检测灵敏度mec A约为800 CFU， test约为200 CFU。给新西兰大白兔注射tst -1。他们的动脉血压被监测，白细胞计数被检查。观察到动脉血压下降和白细胞计数下降。但血清TNF和IL-1无法通过生物检测检测到。我们检测了在不同条件下（Mo、Mo + Tcell、Mo + IL-2、Mo + INF γ、单核细胞），用TSST-1或LPS刺激人分离单核细胞（Mo）产生TNF。各培养上清之间TNF水平无明显差异。

1. We have established the method for detection of genes for staphylococcal enterotoxins and TSST-1 by the polymelase chain reaction (PCR). Five pairs (ent A - D and tst) of oligonucleotid primers were made and tested with clinical isolated strains of S.aureus. The results using PCR and immunological method are almost same within ent A, B, D and tst. But ent C genes were detected by PCR with the strain of S.aureus whose enterotoxin C were not detected by immunological method. The toxical type of most causative strains of post operative MRSA enteritis was ent A, C and tst.2. Next, PCR for mec A and tst was performed with directly extracted staphylococcal DNA from clinical samples (sputum and gastric juice). The sensibilitys for the detection of minimal CFU of MRSA were about 800 CFU for mec A and about 200 CFU for tst.3. New Zealand white Rabbits were injected with TSST-1. Their arterial blood pressure were monitored and their white blood cell count was examined. The decline of the arterial blood pressure and decrease of white blood cell count were observed. But we could not detect serum TNF and IL-1 with bioassay.4. We examined TNF production from human isolated monocyte (Mo) with stimulation of TSST-1 or LPS under various conditions (Mo, Mo + Tcell, Mo + IL-2, Mo + INF gamma, mono nuclear cells). There was no significant deferenciation of TNF level between each culture supernatant.