TNFRSF11B and HIV infectious disease: Another possible mechanism is the interaction between inflammation caused by the two viruses and the immune system, which may lead to upregulation of the receptor activator of the nuclear factor-kappaB ligand (RANKL) and osteoprotegerin (OPG) pathways and, hence, bone resorption, in addition to bone toxicity, as a result of the use of TDF or protease inhibitors to virologically suppress both HBV and HIV infections [59].