To further explain these results an immunoprecipitation assay was performed, and our results are showed in Figure 2B. After VEGF treatment, VEGFR2 protein was detected in Cav-1 immunoprecipitates obtained from HC-MSCs protein extracts; on the contrary, in SSc-MSCs the Cav-1/VEGFR2 co-localization was absent. This evidence concerns the gene KDR and systemic sclerosis.