Chimeric specific antigen epitope‐carrying dendritic cells induce interleukin‐17(+) regulatory T cells to suppress food allergy

Background The on‐purpose‐modulated dendritic cells ( DC s) have shown charming effects on restoring immune regulatory functions in subjects with immune diseases. Objective This study aims to construct DC s carrying chimerical antigen (Ag) peptides ( CAP ‐ DC s) to induce interleukin ( IL )‐17+ inducible Tregs ( iT regs) to alleviate food allergy ( FA ) in a murine model. Methods In this study, we constructed CAP ‐ DC s. The CAP is a fusion protein, consisting of a segment of recombinant scFv of anti‐ DEC 205 antibody and an ovalbumin ( OVA ) epitope ( IC ). A murine OVA ‐ FA model was developed to test the effects of CAP ‐ DC s on suppressing the allergic response in the intestine. Results The CAP ‐ DC s are characterized as that a complex of scFv‐ IC is presented on the surface of the cells, moderately express CD 80 and CD 86 as well as IL ‐6, IL ‐23, transforming growth factor ( TGF )‐β and CCR 9. After being passively transferred with CAP ‐ DC s or injection of scFv‐ IC , Ag‐specific IL ‐17+ Foxp3+ iT regs were induced in the intestinal lamina propria of FA mice. The iT regs showed immune suppressive effects on Ag‐specific Th2 response. FA mice were adoptively transferred with the CAP ‐ DC s or scFv‐ IC injection, which resulted in a significant decrease in the number of Ag‐specific Th2 cells and suppression of FA response in an Ag‐specific manner. Conclusions and Clinical Relevance CAP ‐ DC s can ameliorate FA response by inducing Ag‐specific IL ‐17+ Foxp3+ iT regs and suppressing Ag‐specific Th2 response. To generate CAP ‐ DC s has the translational potential in the treatment of FA .