Intravenous inoculation of Swiss mice with S. aureus leads to severe synovial joint tissue swelling along with prominent T lymphocyte infiltrate with associated
inflammation in synovial tissue.
Cytokines released from macrophages such as TNF-α, IL-1β and
IL-6 the main players that precede cartilage and bone destruction during
septic arthritis (SA) followed by osteoclast differentiation and
bone resorption. CD4+ naïve T cells upon
cytokine driven activation, differentiate into lineages of helper (Th) and regulatory T cells (Treg) including inflammatory Th17 cell lineage. Acting as counterbalance, Tregs protect the host by releasing anti-inflammatory
IL-10. A disturbed balance between Th17 and Treg cell development skews the pathways towards Th17 lineage, but how it actually induces SA is still unexplored. Therefore, this study has been attempted to demonstrate the Th17/Treg ratio in synovial tissue, spleen and peripheral blood by FACS and their derived
cytokines from serum of arthritic mice. Here, we reported that the ratios of Th17/Treg as well as their related
cytokine levels were increased at 3 days post-
infection which was decreased during 9 DPI but heightened again at 15DPI resulting in persistence of the disease, though decreased again at 30 DPI even in animals with increased dose of
infection. Bacterial colonies were present in synovial joints at 15 DPI in animals with increased
infection but found to be absent at 30 DPI. Maintaining Th17/Treg balance by neutralizing functionally active Th17 and their related
cytokines or adoptive transfer of fully active Tregs and/or their related
cytokines may lead to a novel therapeutic strategy for combating Staphylococcal
arthritis.