Comparing Viral (HIV) and Bacterial (Staphylococcus aureus) Infection of the Bone Tissue

This paper focuses on the differences between S. aureus bacterial and HIV viral infection of the bone tissue. Both of these infections alters the RANK/RANKL/OPG signalling dynamics that regulates osteoblasts and osteoclasts behavior in bone remodelling. These infections rapidly lead to severe bone loss and it may even spread to other parts of the body. Since both HIV and osteomyelitis cause loss of bone mass, we focused on comparing the dynamics of these diseases by means of computational models. Firstly, we performed meta-analysis on the gene expression data of normal, HIV and osteomyelitis bone conditions and compare the effects of HIV and S. aureus infection. We mainly focused on RANKL/OPG signalling, the TNF and TNF receptor superfamilies and the NF-kB pathway. Using information from the gene expression data, we estimated parameters for a novel model of osteomyelitis. Then we develop another multi strain HIV ODE model incorporating the HAART therapy. Our ODE modelling aims at investigating the dynamics of the effects of osteomyelitis and HIV infection in bone remodelling.