Feasibility of spermatogonial stem cells separation with alpha 6-integrin and c-kit as specific surface makers in mice / 中国组织工程研究

ABSTRACT

BACKGROUND:It is accepted that the best method for spermatogonial stem cells separation is using artificial cryptorchism model combined with surface makers.OBJECTIVE:To explore the feasibility of separation spermatogonial stem cells with ?6-integrin and c-kit as specific surface markers.DESIGN,TIME AND SETTING:The randomized control experiment was performed at the Renmin Hospital of Wuhan University from May to December 2006.MATERIALS:Forty adult,white Kunming mice with 6 weeks old were randomly divided into cryptorchidism and control groups,with 20 animals in each group.METHODS:Artificial cryptorchidism model was prepared by made an incision at the median of abdomen,and testis was pulled into abdominal cavity,which was fixed at the each side of lateral abdominal wall.There was no treatment in the control group.The single cell suspension of seminiferous epithelium was obtained by traditional two step enzyme digestion at 2-3 months after operation.FITC-conjugated anti-?6-intergrin antibody and PE-conjugated anti-c-kit antibodies were added.Then the cells with low side scatter light-scattering properties were sorted and positively stained for ?6-intergrin and negative c-kit expression.Meanwhile,the viability of the isolated cells was assessed by trypan blue staining.MAIN OUTCOME MEASURES:The morphological changes of cryptorchidism,and the sorting results of spermatogonial stem cells.RESULTS:Cell distribution in seminiferous tubule was disorder with reduced numbers.The layer and lumens were disappeared,and cell division phase could be seen in the center of tubules.Compared to the control group,the testicular cells in the cryptorchidism group were increased in the side scatterlow,Forward scatterhi areas,with figure left-upward displacement.The distribution of ?6-integrin+ and c-kit cells were deviated each other,it named that most ?6-integrin+ cell were not spermatogonial stem cells,so do the c-kit-cells.Only 2.8% of testicular cells exhibited side scatterlow,?6-integrin+,and c-kit-,which were spermatogonial stem cells in the cryptorchidism group.And trypan blue staining showed that over 95% of them were viable.CONCLUSION:Using the two surface markers to sort spermatogonial stem cells can advance the purity of the spermatogonial stem cells in cell suspension,but the specificity is insufficient.