In a cohort of MCTD patients with PAH, a significant correlation was found between the serum AECA levels and both the TM and vWF levels, suggesting that the presence of AECAs and endothelial cell activation may play a role in the development of PAH and in the maintenance of the obliterative vascular process in MCTD patients [88]. This evidence concerns the gene VWF and mixed connective tissue disease.