IFATS Collection: Adipose-Derived Stromal Cells Improve the Foreign Body Response

Abstract

Many implanted devices fail due to the formation of an avascular capsule surrounding the device. Additionally, fat has long been known to promote healing and vascularization. The goals of this study were to identify potential mechanisms of the provascular actions of adiposederived stromal cells (ASCs) and to improve implant biocompatibility. First, adult ASCs and fibroblasts from rats were attached to polyurethane and polystyrene in vitro and their cytokine secretion profile was analyzed. Secretion of vascular endothelial growth factor (VEGF) from ASCs was 10 -70 times higher than fibroblasts after 3 and 6 days. Next, polyurethane, bare and with cellular coatings, was implanted subcutaneously in rats. The fibrous capsule surrounding bare polyurethane implants was 17%-32% thicker and the amount of collagen was 27% greater than the capsule surrounding ASC-coated implants. Finally, the microvessel density adjacent to ASC-coated polyurethane was approximately 50%-80% higher than bare polyurethane. In summary, ASCs attached to polyurethane have a dramatically increased VEGF production compared with fibroblasts in vitro, and these cells also produce an increased microvessel density in the surrounding tissue when implanted subcutaneously in rats.

Adipose Tissue Derived Stem Cells Secretome: Soluble Factors and Their Roles in Regenerative Medicine

“…Another interesting work is the one reported by Prichard et al [55], which revealed that rat ASCs adhered to a polyurethane implant modulate, and in part favoured, the foreign body response to the latter in a rat model. Quite interesting from the perspective of the present review the screenings made on the supernatants of ASCs when seeded in either polystyrene or polyurethane implants.…”

The Roles of Bone Morphogenetic Proteins and Their Signaling in the Osteogenesis of Adipose-Derived Stem Cells

“…2,5,6 For the induction of osteogenesis of ASCs, BMPs are introduced through three ways: the administration of exogenous BMPs, gene technology, and the induction of endogenous BMPs.…”

“…In the presence of osteogenic medium, 50 ng/mL BMP-2 appears to be the minimum dose to obtain a significant difference in extracellular mineralization 37 ; the optimal effect is obtained at approximately 100 ng/mL. 6,37 The amount and type of active agents in osteogenic medium also influence the efficacy of the osteogenic differentiation of ASCs. For example, dexamethasone was one of the main components for the osteogenic differentiation of ASCs in the traditional osteogenic medium.…”

“…[2][3][4] These properties confer human ASCs a promising application potential in the clinic. Several members of the bone morphogenetic protein (BMP) family are robust osteoinductive agents 2,5,6 and have been shown to enhance and accelerate the osteogenesis of ASCs. Further, BMP signaling pathways also mediate the promoting effects of many drugs on the osteogenesis of ASCs.…”

Materials that harness and modulate the immune system

“…In contrast, implants in the epididymal fat pads of rats exhibit less evidence of fibrous capsule formation and extensive neovascularization in implant-adjacent tissues. 24 The mechanisms by which this reduction in foreign body response severity occurs are yet to be clarified. However, groups have shown that adipose-derived stromal cells (ASCs; pluripotent progenitor cells found in fatty tissues) have exceptional regenerative qualities.…”