Figure 4From: Induction of multiple matrix metalloproteinases in human dermal and synovial fibroblasts by Staphylococcus aureus: implications in the pathogenesis of septic arthritis and other soft tissue infectionsPotentiation of matrix metalloproteinase (MMP) protein expression in human fibroblasts by Staphylococcus aureus grown in the presence of recombinant human interleukin (rhIL)-1β. The cell pellets from S. aureus grown in the presence or absence of rhIL-1β were washed repeatedly to prepare cell lysate. Enzyme-linked immunosorbent assay (R&D Systems, Inc., Minneapolis, MN, USA) was carried out to make sure that the bacterial cell lysate was devoid of any traces of rhIL-1β. Confluent monolayers of human dermal fibroblasts were exposed to 25 μg/well of IL-1β-free cell lysate obtained from S. aureus for 48 hours. The supernatants were collected and expression of multiple MMP protein was assessed using multi-MMP-Array kit from RayBiotech, Inc. (Norcross, GA, USA) as described in the text. The data presented show that MMP-2, -3, and 8 are relatively more expressed in fibroblasts treated with S. aureus cell lysate obtained from strain grown in the presence of 5 and 15 ng/ml rhIL-1β. Tissue inhibitor of metalloproteinases (TIMP)-4 expression was also slightly enhanced in fibroblasts treated with S. aureus lysate obtained from strain treated with 15 ng/ml IL-1β.Back to article page