ABSTRACT
BACKGROUND:Spermatogonial stem cel s with abilities of differentiation, self renewal and proliferation are a kind of adult stem cel s that can transfer genetic information into offspring, which have great application prospects in medicine, genetics and zoology. OBJECTIVE:To review the source, biological characteristics, and application of spermatogonial stem cel s as wel as self-renewal and molecular regulation underlining these differentiations. METHODS:PubMed and CNKI databases were searched by the first author using key words of“spermatogonial stem cel , biological characteristics, self-renewal, differentiation”in English and in Chinese, respectively, to retrieve relevant articles published from 1990 to 2015. Literatures addressing spermatogonial stem cel s were included, and 46 articles were chosen for further analysis eventual y. RESULTS AND CONCLUSION:Spermatogonial stem cel s can be cultured in vitro, cryopreserved, and genetical y modified as wel as used for al ogeneic or xenogeneic transplantation, al of which contribute to understanding the mechanisms of spermatogenesis, thereby providing new means for treatment of male sterile disease and genetic diseases and providing new hopes for chemotherapy-induced germ cel damage in young cancer patients. Microenvironment and Plzf, GDNF, SCF/c-Kit signaling pathways can play an important role in the regulation of spermatogonial stem cel self-renewal and differentiation. As a cel model, spermatogonial stem cel s become an important tool for the researches on spermatogenesis mechanism, regeneration of spermatogenesis in sterile individuals and reproduction of transgenic animals.
ABSTRACT
BACKGROUND:Tol-like receptor 4 (TLR4) and its ligand, lipopolysaccharid, are closely associated with the occurrence and development of periodontitis. Meanwhile, the immunological properties of periodontal ligament stem cells (PDLSCs) play an important role in the reconstruction of periodontal tissue and cel-based therapy of periodontitis. However, the effect of TLR4 and lipopolysaccharid on the immunological properties of PDLSCs remains unclear. OBJECTIVE:To investigate the effect of TLR4 on the immunological characteristics of human PDLSCs. METHODS:PDLSCs were isolated by enzyme digestion method as previously reported, and were cultured in the medium containing 10 mg/L lipopolysaccharid, the ligand of TLR4 for 3 days. Using un-treated PDLSCs as controls, we then investigated whether lipopolysaccharid-treated PDLSCs could cause the proliferation of al ogeneic T lymphocytes as wel as the effect of lipopolysaccharid-treated PDLSCs on the mixed lymphocytes reaction and proliferation of lymphocytes induced by phytohemagglutinin. PDLSCs, peripheral blood mononuclear cells and phytohemagglutinin were co-cultured, and the concentration of prostaglandin E2 in the culture supernatant was examined. Then we added indomethacin, which is the inhibitor of prostaglandin E2, into the co-culture system of PDLSCs, peripheral blood mononuclear cells and phytohemagglutinin, and tested the proliferation of lymphocytes. RESULTS AND CONCLUSION:Lipopolysaccharid-treated PDLSCs did not lead to the proliferation of al ogeneic T lymphocytes just as un-treated PDLSCs, and could suppress the mixed lymphocytes reaction and proliferation of phytohemagglutinin-induced lymphocytes. However, the inhibitory ability of lipopolysaccharid-treated PDLSCs was significantly lower than that of un-treated PDLSCs. The levels of prostaglandin E2 were significantly elevated in the co-culture of PDLSCs, peripheral blood mononuclear cells and phytohemagglutinin. After adding of indomethacin, the PDLSCs-suppressed proliferation of lymphocytes restored to normal levels. Lipopolysaccharid weakened the immunosuppressive capacity of PDLSCs, which may be due to the decreasing secretion of prostaglandin E2.
ABSTRACT
The protein expression of cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated Cl(-) channel, in ovarian stimulated premature female rat ovary during a cycle of follicle development and corpus luteum formation was investigated. Animals were injected with 10 U pregnant Mare's serum gonadotropin (PMSG) and subsequently 10 U hCG 48 h later. Time-dependent immunohistochemistry and Western blotting experiments were performed before and 24, 48, 72 h after hCG treatment. The immunohistochemistry revealed that administration of PMSG stimulated the CFTR expression in thecal cell layer and granulosa cell layer of mature follicles 48 h post injection, coincident with the PMSG-induced peak in follicular estradiol. However, the expression of CFTR in the granulose lutein cell layer and thecal lutein cell layer was time-dependently reduced following hCG injection, in accordance with the gradually increased progestogen level during luteum corpus formation. Western blotting analysis demonstrated that rat ovarian tissue expressed the special CFTR band at 170 kD. It is concluded that cAMP-dependent Cl(-) channels are involved in regulation of follicle development and luteum formation.