| First Author | Salagianni M | Year | 2007 |
| Journal | J Immunol | Volume | 178 |
| Issue | 8 | Pages | 4771-8 |
| PubMed ID | 17404257 | Mgi Jnum | J:145203 |
| Mgi Id | MGI:3833814 | Doi | 10.4049/jimmunol.178.8.4771 |
| Citation | Salagianni M, et al. (2007) An essential role for IL-18 in CD8 T cell-mediated suppression of IgE responses. J Immunol 178(8):4771-8 |
| abstractText | The ability of CD8 T cells to suppress IgE responses is well established. Previously, we demonstrated that CD8 T cells inhibit IgE responses via the induction of IL-12, which promotes Th1 and suppresses Th2 responses. In this study, we show that IL-18 also plays an essential role in IgE suppression. In vitro, IL-18 synergized with IL-12 to promote Th1/T cytotoxic 1 and inhibit Th2/T cytotoxic 2 differentiation. OVA-specific TCR transgenic (OT-I) CD8 cells induced both IL-12 and IL-18 when cultured with OVA(257-264) peptide-pulsed dendritic cells. In vivo, IL-18(-/-) mice exhibited higher IgE and IgG1 levels compared with wild-type mice after immunization with OVA/alum. Furthermore, adoptive transfer of CD8 T cells from OVA-primed mice suppressed IgE responses in OVA/alum-immunized mice, but not in IL-18(-/-) mice. IgE suppression in IL-18(-/-) mice was restored if CD8 T cells were coadoptively transferred with IL-18-competent wild-type bone marrow dendritic cell progenitors, demonstrating an essential role of IL-18 in CD8 T cell-mediated suppression of IgE responses. The data suggest that CD8 T cells induce IL-18 production during a cognate interaction with APCs that synergizes with IL-12 to promote immune deviation away from the allergic phenotype. Our data identify IL-18 induction as a potentially useful target in immunotherapy of allergic disease. |
