The occurrence of mastitis will cause reduction in the milk yield, abnormality of the milk quality, and elimination of the cow, and the extra manpower and the medicament expenditure are needed to to cure the mastitis, which is the most serious economic problem in the dairy farming industry. The problem of using antibiotics presently for curing is the tendency of causing the problems of medicine-resistant bacteria and antibiotics residual in the dairy product, making vaccine the best solution, although the vaccine is not commercially available in the domestic market. According to the research, it is pointed out that the first step of the Staphylococcus aureus to invade into a host is to utilize the clumping factor A (ClfA) to combine with the fibrin of the hosts epithelial cell, which is viewed as an important virulence factor, and it is confirmed that the vaccine can induce the excellent immune reaction and block the Staphylococcus aureus from adhering to the epithelial cell of the mammary gland. The disclosed research successfully expresses the ClfA recombinant proteins to be combined with the water-in-oil-in-water adjuvant in the immune rat, which can not only reduce the kidney bacterial amount and symptom of the rat after attack, but also have the higher antibody reaction than that of the control group on 14th and 21th day after immune reaction and is higher in the immune group than the control group after 28 days as displayed by the cell proliferation result.乳房炎發生後,會造成乳量減少、乳質異常和牛隻的淘汰,且需投入額外人力及藥物經費來治療乳房炎,是酪農業最嚴重的經濟問題。目前使用抗生素來做治療,易產生抗藥性細菌及乳品抗生素殘留問題,疫苗是最好的解決之道,但國內尚無市售疫苗。根據研究指出金黃色葡萄球菌入侵宿主的第一步是利用表面黏附蛋白(clumping factor A,ClfA)結合宿主上皮細胞的纖維蛋白,視為重要的毒力因子,且已證實能引起良好免疫反應及阻斷金黃色葡萄球菌貼附乳腺上皮細胞。本研究成功表現ClfA重組蛋白,結合水包油包水佐劑免疫小鼠,攻毒後不僅能降低小鼠腎臟菌量及病徵,且於免疫14、21天時較對照組有高的抗體反應,在細胞增生結果顯示於28天免疫組較對照組高。
