Research
Human amniotic epithelial cells do not express on their surfaces HLA-A, B, C, and DR antigens, or β2-microglobulin. In vitro these cells synthesise the enzymes lacking in patients with selected enzymatic deficiencies: the survival of a transplanted monolayer of human amniotic epithelial cells was therefore investigated in seven volunteers. None of the volunteers showed clinical signs of acute rejection. [Read More]
Postlaminectomy epidural adhesion is implicated as a main cause of ‘‘failed back surgery syndrome’’ and associated with increased risk of complications during revision surgery. Various materials acting as mechanical barriers to reduce fibroblasts infiltration into epidural space have met with limited success. In present research, amniotic membrane (AM) was studied to investigate its effects on reducing epidural scar adhesion after laminectomy in a canine model. Laminectomy sites were created at L-1, L-3, L-5, and L-7 levels in 24 adult mongrel dogs. [Read More]
Stem cells capable of differentiating to multiple lineages may be valuable for therapy. We report the isolation of human and rodent amniotic fluid–derived stem (AFS) cells that express embryonic and adult stem cell markers. Undifferentiated AFS cells expand extensively without feeders, double in 36 h and are not tumorigenic. Lines maintained for over 250 population doublings retained long telomeres and a normal karyotype.[Read More]
Mesenchymal stem cell‐derived exosomes (MSC‐Ex) play important roles in tissue injury repair, however, the roles of MSC‐Ex in skin damage repair and its mechanisms are largely unknown. Herein, we examined the benefit of human umbilical cord mesenchymal stem cell derived exosome (hucMSC‐Ex) in cutaneous wound healing using a rat skin burn model. We found that hucMSC‐Ex‐treated wounds exhibited significantly accelerated re‐epithelialization, with increased expression of CK19, PCNA, collagen I (compared to collagen III) in vivo. HucMSC‐Ex promoted proliferation and inhibited apoptosis of skin cells after heat‐stress in vitro. We also discovered that Wnt4 was contained in hucMSC‐Ex, and hucMSC‐Ex derived Wnt4 promoted β‐catenin nuclear translocation and activity to enhance proliferation and migration of skin cells, which could be reversed by β‐catenin inhibitor ICG001. In vivo studies confirmed that the activation of Wnt/β‐catenin by hucMSC‐Ex played a key role in wound re‐epithelialization and cell proliferation. Furthermore, knockdown of Wnt4 in hucMSC‐Ex abrogated β‐catenin activation and skin cell proliferation and migration in vitro. The in vivo therapeutic effects were also inhibited when the expression of Wnt4 in hucMSC‐Ex was interfered. In addition, the activation of AKT pathway by hucMSC‐Ex was associated with the reduction of heat stress induced apoptosis in rat skin burn model. Collectively, our findings indicate that exosome‐delivered Wnt4 provides new aspects for the therapeutic strategy of MSCs in cutaneous wound healing.[Read More]
Amniotic membrane (AM), the most internal placental membrane, has unique properties including antiadhesive effects, bacteriostatic, wound protection and pain-reduction properties, as well as epithelialization initialization capacities. Furthermore, AM is widely available and less costly than other bioengineered skin substitutes. In a prospective pilot study, we evaluated the safety, feasibility, and the effects on healing of AM graft in 15 patients with chronic venous leg ulcers. AM grafts were prepared from placentas harvested during cesarean section. All grafted AM had adhered to the wound bed 7 days after being applied with a 100% engraftment rate. The percentage of granulation tissue increased significantly (from 17% on day 0 to 69% on day 14, p < 0.0001), along with a significant decrease of fibrinous slough (from 36% at day 0 to 16% at day 14,p < 0.001).[Read More]
Aim: To evaluate the safety & effectiveness of the amniotic membrane dressing in the management of varicose ulcers. Materials & Methods: A prospective comparative study was conducted in the department of surgery, A.J. hospital & research centre, India, from Jan 2010 to Jan 2012. 200 cases with leg varicose ulcers were studied,[Read More]
Amniotic membrane (AM) is the inner most extraembryonic membrane that surrounds the foetus in a sac of amniotic fluid, functioning as a protective barrier to ascending infection and trauma during pregnancy[1,2]. This is separated from a single layer of cuboidalepithelium by a basement membrane (BM). [Read More]
Amniotic fluid (AF) is a marvelously complex and dynamic milieu that changes as pregnancy progresses. AF contains nutrients and growth factors that facilitate fetal growth, provides mechanical cushioning and antimicrobial effectors that protect the fetus, and allows assessment of fetal maturity and disease. [Read More]
Biopsy specimens from the beds of leg ulcers of fifteen patients were obtained before and after the application for 5 days of cultured human amnion. After amnion application there was considerable granulation tissue in the ulcer bed and microscopical evidence of thinned connective tissues, vessel development, more compact resolution of vascular basement membranes, and many more factor VIII granules within endothelial cells. [Read More]
Human amniotic membrane proved to be a versatile and useful temporary biologic dressing in studies involving 120 patients. Wounds, both traumatic and nontraumatic in origin, responded to a protocol that allowed coverage of tissues as diverse as exposed bowel, pleura, pericardium, blood vessels, tendon, nerve and bone. Wounds unresponsive to usual therapeutic measures responded to membrane application.[Read More]