[ effect of laminin and gelatin extracellular matrix on short-term cultivation of neonate mouse spermatogonial stem cells]

To compare the effect of laminin and gelatin on short-term culture of spermatogonial stem cells [SSCs] from neonatal mouse testes. Cell suspension containing SSCs were isolated from testes of 6 day-old mice and cultured in the presence of Glial-derived neuroterophic factor [GDNF], Epidermal Growth Factor [EGF] and Basic Fibroblastic Growth Factor [bFGF] on laminin-and gelatin-coated plates for 9 days. Number and area of colonies were measured in 5th, 7th and 9th days after culturing. At 9th day Immunostaining was used to detect expression of SSC markers, alpha 6-Integrin and beta 1-Integrin. moreover, the colonies were harvested and the percentage of alpha 6-Integrin and beta 1-Integrin positive cells was assessed by flowcytometery in both groups. Immunostaining analysis showed that our culture system contained SSC colonies as they were positive for alpha 6-Integrin and beta 1-Integrin. Additionally, the number of colonies those were formed on laminin were significantly higher in comparison with those of other group. but colony area was higher on gelatin. There was no significant difference in percentage of cells that expressed alpha 6-Integrin, beta 1-Integrin detected by flowcytometry in both groups. laminin as extracellular matrix cause to increase the number of neonate spermatogonial colonies and decrease the area of them [P

Effect of extracellular matrix on differentiation of mouse embryonic stem cells into insulin-producing cells

Evaluation of extracellular matrics [ECMs] effect on differentiation of embryonic stem cells [ESCs] to pancreatic beta-cell. Mouse ESC line, Royan B1, was subjected to differentiation into beta-like cells in a three-step method: generation of embryoid bodies [EBs], spontaneous differentiation and induction by Nicotinamide onto different matrices including poly L-ornithine/laminin, gelatin, and two different dilution of matrigel [1:30, 1:100] and control group [no ECM]. At the final step, differentiated cells were analyzed for expression of some pancreas-specific genes using "semi-quantitative RT-PCR ", for detection of insulin and C-peptide presence in cells using "immunocytochemistry" and for the evaluation of the amount of secretd insulin in response to glucose Using "insulin secretion assay". The semi-quantitative RT-PCR analysis of differentiated cells on 1:30 matrigel coated-plates showed consistent higher expression of beta-cell specific markers including Insulin I, Insulin II, Slc2a2 in comparison to the other ECMs. The results of immunostainig for C-peptide showed no significant differences between the experimental groups and finally insulin secretion assay revealed that differentiated cells on 1:30 matrigel coated-plates secreted more insulin in response to glucose in comparison to the other ECMs. Our results suggest that type of ECM may influence ESC differentiation into insulin-secreting cells and 1:30 matrigel was more effective. However, the success rate of differentiation needs further investigations using other appropriate ECMs