 2. Vascular Progenitor Cells and the Pathogenesis of Systemic SclerosisOriginally listed separately as DAIT SCSSc-01-02, NCT00871221. The purpose of this study is to measure and characterize the circulating endothelial progenitor cells from the blood of 30 participants and also to determine the extent of vascular cell apoptosis and proliferation in cutaneous microvasculature in these participants before and after the receipt of the two SCOT treatment regimens. 