Background/Purpose:

Systemic sclerosis (SSc) is autoimmune disease characterized by autoimmunity, diffuse fibrosis in the skin and internal organs, and vasculopathy in moderate size arteries and arterioles. The vasculopathy associated with SSc is one of the major contributors to the clinical manifestations of the disease and can result in non healing ulcers, gangrene and digit loss, hypertension and cardiovascular disease and it has a profound impact on the quality of life. Endothelial injury, smooth muscle cells proliferation and fibrosis of the vessel wall result in lumen occlusion and tissue hypoxia that is treated currently with pharmacologic agents.  New therapies including stem cells are needed to reconstitute the diseased vascular tissue. Adipose derived stem cells (ADSCs) represent an ideal stem cell source for SSc vasculopathy therapy.

The aim of this study is to investigate if human ADSCs can be differentiated into smooth muscle cells (SMC) and endothelial cells (EC) and if these differentiated cells can be constructed into cell sheets and vascular tissue.

Methods:

Human ADSCs were isolated expanded, induced into EC and SMC using endothelial growth medium-2 (EGM-2) and Transforming growth factor (TGF-β1) respectively. The growth and morphology of the cells were followed up for 4 weeks. The phenotype of induced cells were checked for SMC markers; actin, calponin and heavy chain myosin and for endothelial cell markers; CD31 and Von Willebrand factor (vWF) through immunocytochemistry and western blot. The induced SMC and EC cells were used to construct either SMC and EC cell sheets or bilayered vascular structures by culturing them in special culture dishes. Confluent cultured cells were harvested as a contiguous cell sheet only by lowering temperature. The cell sheets and vascular structures were stained with H&E and Masson Trichrome and verified for smooth muscle markers and for endothelial cell markers. The formation of extracellular matrix of the both cell sheets was tested using Picrosirius Red staining and collagen IV.

Results:

The induced cells showed positive staining for endothelial cell markers after 2 weeks and smooth muscle markers after 3 weeks for SMC cells. The western blot confirmed their phenotype conversion. The cell sheets and vascular structures were detached easily in a consistent manner by lowering the temperature in intact and viable condition. The monolayer cell sheets were formed of 2–5 cell layers that showed positive staining for either SMC or EC markers. They also showed positive staining for Picrosirius Red and collagen IV indicating the formation of extracellular matrix. Vascular structures exhibited upper layer of EC and multiple layers of SMC with collagen layer in between.

Conclusion:

The results showed the ability of human ADSCS to form SMC and EC and constitute renewable source for cellular therapy. The cell sheets and vascular structures made of ADSCs form new technology for improvement of vascular dysfunction in SSc.

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« Back to 2012 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/adipose-derived-stem-cells-as-an-alternative-source-of-cellular-repair-for-vascular-dysfunction-in-systemic-sclerosis/