Methods; We assessed oral delivery of Lactococcus lactis expressing an IL-27 hyperkine on the innate immune response in vivo in a genetically intact, non-infective acute murine colitis model induced by intra-rectal instillation of 2,4,6-Trinitrobenzenesulfonic acid in SJL/J mice.
Results; IL-27 attenuates acute severe colitis through reduction of colonic mucosal neutrophil infiltrate associated with a decreased CXC chemokine gradient. This suppression was T cell-independent and IL- 10-dependent, initially featuring enhanced mucosal IL-10. IL-27 was associated with a reduction in colonic pro-inflammatory cytokines and induced a multifocal strong positive nuclear expression of phosphorylated STAT-1 in mucosal epithelial cells.
Conclusion; We have defined novel mechanisms of IL-27 immunosuppression towards colonic innate immune responses in vivo. Mucosal delivery of IL-27 has translational potential as a novel therapeutic for IBD and is a future mucosal directed rescue therapy in acute severe inflammatory bowel disease.
Bibliographical noteThis work was supported in part by the Intramural Research Program of the National Institutes of Health, National Cancer Institute, as well as a fellowship funded by Crohn’s and Colitis Foundation of America (MHM) and a grant from the Broad Medical Research Foundation. This project has been funded in whole or in part with Federal funds from the National Cancer Institute, National Institutes of Health, under Contract No. HHSN261200800001E (MRA). The content of this publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.