奶牛乳腺上皮细胞的分泌、免疫与乳体细胞数的相关研究

项目名称： 奶牛乳腺上皮细胞的分泌、免疫与乳体细胞数的相关研究

项目编号： No.30871800

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 赵国琦

作者单位： 扬州大学

项目金额： 30万元

中文摘要： 为解决我国牛奶中体细胞数过多这一问题，本项目利用泌乳奶牛进行饲养试验，研究了泌乳阶段和胎次对血液的免疫细胞和乳体细胞的变化、相关氧化酶活性的变化；通过乳腺上皮细胞体外培养技术，获得乳腺上皮细胞，并构建乳腺上皮细胞腔，对乳腺上皮细胞的分泌和免疫功能进行了研究，结果如下：随胎次的增加，乳脂肪酶活性显著降低，过氧化氢酶活性显著增加，过氧化物酶活性先升高后降低；乳体细胞主要是巨噬细胞、粒细胞、淋巴细胞（乳中白细胞）和少量上皮细胞，随胎次的增加，乳中巨噬细胞比值显著增加，淋巴细胞比值极显著降低；牛乳体细胞数随胎次而显著增加；外周血中白细胞组成比例在不同胎次间的变化比较稳定，在一定范围内波动，随着胎次的增加，巨噬细胞的比值有降低趋势，粒细胞的比值有所升高，淋巴细胞的比值有降低趋势，但各胎次间差异不显著；巨噬细胞受到病原刺激后通过提高IL-6和TNF-αNA的表达量提高了天然免疫的作用；单核细胞和巨噬细胞在受到LPS刺激24h后，TLR2和TLR4蛋白水平表达量相对提高，证实了TLR2和TLR4在单核细胞及其由来的巨噬细胞抵抗病原物质感染时发挥了重要作用。

中文关键词： 奶牛；乳腺上皮细胞；分泌；免疫；体细胞数

英文摘要： To solve the high Somatic Cell Count（SCC）in milk problem in our country, this project used lactating dairy cows feeding experiment to evaluate the effect of lactation period and parity on the varieties of immunocyte in blood, SCC in milk, and relative oxidase activities; Mammary Epithelial Cells (MEC) in vitro culture method was used to obtain the MEC and built up the MEC cavity to study the secretion and immunity function of MEC, the results are as follows：With the increase of parity, milk lipase activity decreased while catalase activity increased, peroxidase activity increased firstly and then decreased. The SCC in milk are mainly composed of macrophages, polymorphonuclear neutrophil leucocytes, lymphocyte (leukocyte in milk) and a small amount of epithelia; the macrophages percentage and SCC increased significantly while lymphocyte percentage dramatically decreased with the increase of parity. In peripheral blood, the ratio of composition in leukocyte was steady changed and flutuated in a centain range by parity. The ratio of macrophages and lymphocyte tended to decrease, while that of polymorphonuclear neutrophil leucocytes increased with the increased of parity; however, there was no remarkble difference among parities. Macrophages enhanced IL-6 and TNF-αNA expressions to increase the innate immunity activation by pathogen stimulation; monocytes and macrophages enhanced Toll-like receptors 2 (TLR2) and TLR4 protein expressions by lipopolysaccarid (LPS) stimulation for 24h, which confirmed that TLR2 and TLR4 played the important functions in resisting pathogeny infection by monocytes and monocytes - derive macrophages.

英文关键词： dairy cow; Mammary Epithelial Cells; secretion; immunity; Somatic Cell Count