Aspectos regenerativos e imunomodulatórios das células estromais mesenquimais do tecido adiposo em modelo murino de anemia falciforme

Abstract

Chronic leg ulcers (CLU) are common microvascular complications in patients with sickle cell anemia. CLUs are recalcitrant and the absence of treatment can lead to lower limb amputation. Adipose tissue stromal cells (ASC) represent an alternative for the treatment of CLUs, due to their ability to secrete soluble mediators involved in tissue repair. Thus, we evaluated the effects of the ASC secretome in vitro model of umbilical cord endothelial cells (HUVECs) and in vivo model with transgenic Nestin- GFP+/NG2-DsRed+ mice and sickle Towness mice. Our work found that the secret of ASC preconditioned in normoxia (condition with 20% oxygen) and hypoxia (condition with 5% oxygen) presented in its composition markers of tissue regeneration (eg: VEGF, MCP1, IL-8 and angiogenin). In vitro analysis demonstrated that both conditioned media (CMs) exerted anti-apoptotic and angiogenic action on HUVECs, with better performance of cells treated with CM in normoxia. Our in vivo model using C57BL/6 transgenic mice revealed radiation from the healing process of wounds treated with MCs. Considering that our therapeutic product performed better under conditions of normoxia, we analyzed the therapeutic potential of MC normoxia in wound healing model with sickle cell mice. In this work, we sought to evaluate the proangiogenic and immunomodulatory effect in skins treated with CM using immunohistochemistry, immunofluorescence and RT-PCR techniques. Our results revealed that CM administration was able to stimulate the healing process by reducing local inflammation, increasing the number of fibroblasts and increasing collagen production. Just as we identified reduced expression of inflammatory transcripts, evidencing the therapeutic effect of MC on immunomodulation.