Enhanced Systemic Response of Matrix Metalloproteinases and Their Regulators in Campylobacter and Salmonella Patients

Campylobacters are major enteropathogens worldwide with a substantial financial burden. Matrix metalloproteinases (MMPs) are proteolytic metalloendopeptidases with ability to modify immune response and shown to be upregulated in patients with several tissue destructive diseases, including infections. We measured here serum concentrations of MMP-8 and MMP-9 together with their regulators myeloperoxidase (MPO), human neutrophil elastase (HNE), and tissue inhibitor of metalloproteinases (TIMP)-1 in 80 Campylobacter and 25 Salmonella patients as well as in 27 healthy controls. Paired serum samples were available for 73 and 23 patients, respectively. When the initial serum samples were compared to those from controls, both Campylobacter and Salmonella patients showed elevated concentrations of all biomarkers tested (p ≤ 0.037). In the follow-up samples, collected about 25 days afterwards, MMP-8 levels of Campylobacter patients had already turned to normal but all the other biomarkers still showed elevated, although from the initial levels significantly dropped, levels. For the follow-up samples of Salmonella patients, only MMP-9 and MPO levels were at a significantly higher level than in controls. It remains to be studied if the systematically enhanced neutrophil-derived proteolytic and oxidative stress, induced by Campylobacter infection as shown here and persisting for several weeks, is important for the development of late sequelae.