Oral administration of Lactococcus lactis expressing recombinant 15-lipoxygenase-1 (15 LOX-1) modulates chemically induced colitis in mice

Background: Inflammatory bowel disease (IBD), such as Crohn's disease and ulcerative colitis, are characterized by extensive inflammation due to dysregulation of the innate and adaptive immune system whose exact etiology is not yet completely understood. Currently there is no cure for IBD, thus the search for new molecules capable of controlling IBD and their delivery to the site of inflammation are the goal of many researchers. The aim of this work was to evaluate the anti-inflammatory effect of the oral administration of a Lactococcus (L.) lactis strain producing 15-lipoxygenase-1 (15-LOX-1) using a dextran sodium sulfate (DSS)-induced IBD mouse model. Methods: The anti-inflammatory strain L. lactislacti NCDO 2118 was modified to produce active 15-LOX-1 and tested in in a DSS induced IBD mouse model. Results: This 15-LOX-1 producing L. lactis was effective in the prevention of the intestinal damage associated to inflammatory bowel disease in a murine model and decreased pro-inflammatory cytokines such as IFN-γ and IL-4 while increasing the anti-inflammatory cytokine IL-10. L. lactis NCDO 2118 acts not just as a tool to delivery 15-LOX-1 in the inflamed gut mucosa but still retains its anti-inflammatory effects. Conclusions: This strain could be used in novel adjunct IBD treatment protocols.