COL5A2 and systemic sclerosis: As expected, we found a significant decrease in the mRNA COL5A2 expression in the SSc cells cultured with COL5A2 siRNA transfection compared to the mRNA COLVA2 in the SSc fibroblasts not transfected (0.19 ± 0.0182 vs. 1.40 ± 0.15; p < 0.0001) (Figure 4A).