Authors : Chunyan Lu, Runjun Yang , Boyang Liu , Zezhong Li , Binglei Shen , Shouqing Yan , Yonghong Zhang , Liying Zhang and Zhihui Zhao
Abstract: Chinese Holstein dairy cow is the main dairy cow in China. With the development of Chinese milk industry, more attention is being placed on the factors that might affect milk quality, especially milk fat and milk protein content. So, the objective of this study was to establish a culture system for two types of bovine mammary epithelial cell line, high fat high protein Mammary Epithelial Cell line (MEC-HH) and low fat low protein Mammary Epithelial Cell Line (MEC-LL) in vitro and elucidate the unique characteristics of these cell lines. Mammary tissues from two lactating dairy cows whose milk were high fat high protein content and low fat low protein content were used as sources of these epithelial cell lines. The tissues were cultured in plastic dishes by the method of tissue nubbles culture. Fibroblast and epithelial cells successively grew and extended from mammary tissues after 6 days from low fat low protein cow but 10 days from high fat high protein cow and pure epithelial cells were obtained by continuous culture and digestion for 3-5 times. The epithelial cells cultured in the 10% FBS maintained a normal growth tendency and had normal cell nucleus. The α-s1 casein and κ-casein expression of epithelial cells were detected by RT-PCR. The positive immunocytochemistry to cytokeratin 18 suggested the obtained cell line exhibited the specific character of epithelial cells. A TG-kit was used to detect the TG content of the two types of cells, the results showed that the cell lines kept the character of high fat and low fat cows in the 1st and 2nd passages. The obtained mammary epithelial cell lines had normal morphology, growth characteristics, cytogenetic and secretory characteristics. Thus, it might supply a useful tool for studying the gene function about milk fat and protein. The research provides the basis for the future study of lipometabolism mechanism in dairy cow.
Chunyan Lu, Runjun Yang , Boyang Liu , Zezhong Li , Binglei Shen , Shouqing Yan , Yonghong Zhang , Liying Zhang and Zhihui Zhao , 2012. Establishment of Two Types of Mammary Epithelial Cell Lines from Chinese Holstein Dairy Cow. Journal of Animal and Veterinary Advances, 11: 1166-1172.