Knocking out mouse BMP9 gene induced capillarization of LSECs in vivo, while treatment with an addition of BMP9 maintained the fenestration of primary cultured LSECs in vitro, and an absence of LSEC fenestrae occurred followed by liver inflammation and fibrosis in BMP9 gene knock-out mice (Miyao et al., 2015; Desroches-Castan et al., 2019). This evidence concerns the gene GDF2 and Hepatitis.