Autoimmunity reviews
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Autoimmunity reviews · Aug 2011
ReviewCellular players in angiogenesis during the course of systemic sclerosis.
Vascular endothelial injury in Systemic Sclerosis (SSc) leads to pathological changes in the blood vessels that adversely impact the physiology of many organs, resulting in chronic tissue ischemia. The response to hypoxia induces complex cellular and molecular mechanisms in the attempt to recover endothelial cell function and tissue perfusion. The progressive losses of capillaries on one hand, and the vascular remodeling of arteriolar vessels on the other, result in insufficient blood flow, causing severe and chronic hypoxia. ⋯ Although hematopoietic endothelial progenitor cells (EPC) count in the peripheral blood of SSc patients is still a matter of controversy, alterations in mobilization process, an excessive immune-mediated EPC destruction in the peripheral circulation or in the bone marrow, a progressive depletion of EPCs following homing to ischemic tissues under persistent peripheral vascular injury, an intrinsic functional impairment could lead to poor vasculogenesis. Human mesenchymal stem cells represent an alternative source of endothelial progenitor cells and it has been observed that their angiogenic potential is reduced in SSc. Targeting autologous stem and progenitor cells could be an ideal tool to counteract and repair dysfunctional angiogenesis.