本研究表达并提纯了无毒诱变葡萄球菌肠毒素C与谷胱甘肽硫转移酶重组融合蛋白(GST-mSEC)。用GST—mSEC作免疫抗原对小鼠进行免疫,研究其对金黄色葡萄球菌(金葡菌)经乳导管注射感染的免疫效果。试验结果表明,在小鼠乳腺感染金葡菌3d后,免疫小鼠乳腺的眼观病理变化显著轻于未免疫的对照组,乳腺组织中的菌数也明显低于未免疫的对照组。GST—mSEC免疫小鼠可引起大量的特异性抗体产生,并对葡萄球菌超抗原刺激的炎症性细胞因子的产生具有显著的中和抑制作用。结果表明GST—mSEC融合蛋白及其诱导的特异性抗体对金葡菌引起的乳腺感染具有良好的抗感染作用。
To investigate immune protection of glutathione S-transferase and mutant staphylococcal enterotoxin C fusion protein (GST-mSEC) against Staphylococcus aureus intramammary infection, mice were immunized with the GST-mSEC in alum adjuvant and challenged with viable S.aureus through the teat canal of mouse mammary. The results showed that the gross pathological changes in the mammary gland of immunized significantly lower than those of control mice. Immunization mice were noticeably alleviated and the bacteria counts were with GST-mSEC induced strong production of specific anti-SEC antibodies. Furthermore, serum samples from mice immunized with GST-mSEC could effectively inhibit cytokine production in spleen cell cultures induced by SEC. These results suggest that vaccination with GST-mSEC provides protection against S.aareus intramammary infection and that the protection might be mediated by SEC-neutralizing antibody.