CCN4 and idiopathic pulmonary fibrosis: To our surprise and contrary to what others have reported [35], we did not observe any direct effect of WISP1(1000 nM) treatment in initiating the induction of profibrotic genes increase, particularly for collagens such as COL1A1, COL3A1, and ACTA2, and FN1 in NHLF (Figure 4A), IPF-DHLF (Figure 4B), and NHDF (Figure 4C).