Reliminary Isolation And Identification Of Stem Cells From Holstein Mammary

Holstein cow is one of the world’s major dairy breeds, also is the feed required minimum breed which produces per unit of milk varieties. There is close contact between mammary stem cells and milk production. The mammary stem cells are also the important materials for biological reactor research.In order to obtain the mammary stem cells, cow mammary were digested with400units/ml collagenase at37℃for20hours. And then the obtained primary mammary cells were screened and purified by suspension culture and adherent culture. The acquired stem cells have the following characteristics.(1) They were been induced and differentiated into osteoblasts. And they could be stained by alizarin red, which was a characteristic of osteoblasts.(2) They have self-renewal capacity. They could form mammosphere-like cell mass by suspension culture. They also expressed stem cell markers like Nanog, Sox2, Oct4and the mammary stem cells reference markers like CD24, CD29and CD49f.In addition, those cells we gained have great cell activities after the procedure of frozen in liquid nitrogen and thawed and normal diploid after identified by the number of chromosome analysis. So these cells were showed to have good genetic stabilities.