TIMP1 and coinfection: Under our experimental conditions, well-known fibrogenic genes, including αSMA (ACTA2), isoforms of collagenase (COL1A2 and COL3A1), transforming growth factor-beta (TGF-β), tissue inhibitor of metalloproteinase (TIMP, except TIMP1), and matrix metalloproteinase (MMP, except MMP1) were not induced in LX-2 cells by HCV and HIV mono- and co-infection of MLH co-cultures (Figs 6 and S2).