Development of recombinant vaccines against IL-12/IL-23 p40 and in vivo evaluation of their effects in the downregulation of intestinal inflammation in murine colitis.

Overexpression of IL-12 and IL-23, which share the p40 subunit, has been implicated in the pathogenesis of Crohn's disease. Targeting these cytokines with monoclonal antibodies has emerged as a new and effective therapy, but one with adverse reactions. In this study, we sought to develop p40 peptide-based virus-like particle vaccines that elicit autoantibodies to IL-12 and IL-23 for a long-term treatment of the disease. Three vaccines (named C, D and F) against the p40 were developed by inserting peptides derived from p40 into the carrier, hepatitis B core antigen, using molecular engineering methods. Immunization with the vaccines, without the use of adjuvants, induced high titered and long-lasting antibodies to IL-12, IL-23 and p40. The three vaccines were evaluated in vivo in 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced chronic murine colitis. Mice were immunized with a vaccine three times, followed by weekly intrarectal administrations of TNBS. Vaccine groups, especially groups C and F, showed reduced expression of IL-12/IL-23p40, less inflammation, and decreased collagen deposition in colon tissues when compared with controls. We concluded that IL-12/IL-23p40 vaccines may be a potential therapeutic approach in the treatment of Crohn's disease and other autoimmune diseases.