Schematic depicting the overall effect of HIV/HCV co-infection on progression of liver disease. TIMP1 (tissue inhibitors of metalloproteinase 1), COL1A1 (Collagen, type I, alpha 1), MMPs (matrix metalloproteinase), TRAIL (TNF-related apoptosis-inducing ligand), TGF-β (transforming growth factor beta), NFkB (nuclear factor kappa-B), ROS (reactive oxygen species), CCR5 (C–C chemokine receptor type 5)