CCN2 and Hepatic fibrosis: Indeed, high numbers of CD9hi macrophages have been found in fibrotic regions of the liver (Seidman et al., 2020; Daemen et al., 2021; Ramachandran et al., 2019; Remmerie et al., 2020), and these cells are able to prime quiescent primary murine hepatic stellate cells to upregulate the expression of fibrillar collagen through CTGF (Ramachandran et al., 2019), thereby promoting and exacerbating liver fibrosis.