Reduced connexin 43 in eutopic endometrium and cultured endometrial stromal cells from subjects with endometriosis.

Accumulating evidence indicates that reduced fecundity associated with endometriosis reflects a failure of embryonic receptivity. Microdomains composed of endometrial gap junctions, which facilitate cell-cell communication, may be implicated. Pharmacological or genetic inhibition of connexin (Cx) 43 block human endometrial cell differentiation in vitro and conditional uterine deletion of Cx43 alleles cause implantation failure in mice. The aim of this study was to determine whether women with endometriosis have reduced eutopic endometrial Cx43. Cx26 acted as a control. Endometrial biopsies were collected from age, race and cycle phase-matched women without (15 controls) or with histologically confirmed endometriosis (15 cases). Immunohistochemistry confirmed a predominant localization of Cx43 in the endometrial stroma, whereas Cx26 was confined to the epithelium. Cx43 immunostaining was reduced in eutopic biopsies of endometriosis subjects and western blotting of tissue lysates confirmed lower Cx43 levels in endometriosis cases, with Cx43/ß-actin ratios=.4±1.5 in control and =1.2±0.3 in endometriosis biopsies (P<0.01). When endometrial stromal cells (ESC) were isolated from endometriosis cases, Cx43 levels and scrape loading-dye transfer were reduced by ∼45% compared with ESC from controls. In vitro decidualization of ESC derived from endometriosis versus control subjects resulted in lesser epithelioid transformation and a significantly reduced up-regulation of Cx43 protein (1.2±0.2- versus 1.7±0.4-fold, P<0.01). No changes in Cx26 were observed. While basal steady-state levels of Cx43 mRNA did not differ with respect to controls, ESC from endometriosis cases failed to manifest a response to hormone treatment in vitro. In summary, eutopic endometrial Cx43 concentrations in endometriosis cases were <50% those of controls in vivo and in vitro, functional gap junctions were reduced and hormone-induced Cx43 mRNA levels were blunted.

Transplantation of mesenchymal stem cells cultured on biomatrix support induces repairing of digestive tract defects, in animal model.

Transplanted mesenchymal stem cells (MSCs) appear to play a significant role in adult tissue repair. The aim of this research was to obtain MSCs enriched, three dimensional (3D) patches for transplant, and to test their ability to induce repair of iatrogenic digestive tract defects in rats. MSCs were obtained from human and rat bone marrow, cultured in vitro, and seeded in a collagen-agarose scaffold, where they showed enhanced viability and proliferation. The phenotype of the cultured cells was representative for MSCs (CD105+, CD90+, and CD34-, CD45-, CD3-, CD14-). The 3D patch was obtained by laying the MSCs enriched collagen-agarose scaffold on a human or swine aortic fragment. After excision of small portions of the rat digestive tract, the 3D patches were sutured at the edge of the defect using micro-surgical techniques. The rats were sacrificed at time-points and the regeneration of the digestive wall was investigated by immunofluorescence, light and electron microscopy. The MSCs enriched 3D patches were biocompatible, biodegradable, and prompted the regeneration of the four layers of the stomach and intestine wall in rats. Human cells were identified in the rat regenerated digestive wall as a hallmark of the transplanted MSCs. For the first time we constructed 3D patches made of cultured bone marrow MSCs, embedded into a collagen-rich biomatrix, on vascular bio-material support, and transplanted them in order to repair iatrogenic digestive tract defects. The result was a complete repair with preservation of the four layered structure of the digestive wall.