| First Author | Resende M | Year | 2013 |
| Journal | J Immunol | Volume | 191 |
| Issue | 1 | Pages | 262-73 |
| PubMed ID | 23729437 | Mgi Jnum | J:205365 |
| Mgi Id | MGI:5544684 | Doi | 10.4049/jimmunol.1203518 |
| Citation | Resende M, et al. (2013) Leishmania-infected MHC class IIhigh dendritic cells polarize CD4+ T cells toward a nonprotective T-bet+ IFN-gamma+ IL-10+ phenotype. J Immunol 191(1):262-73 |
| abstractText | A differential behavior among infected and bystander dendritic cells (DCs) has been explored in different infection models. We have analyzed both populations sorted on contact with visceral Leishmania infantum on a susceptible mice model evaluating the subsequent repercussions on adaptive immune response. Our results demonstrate a clear dichotomy between the immunomodulatory abilities of bystander and infected DCs. The bystander population presents increased levels of IL-12p40 and costimulatory molecules being capable to induce CD4(+) T cell activation with immune protective capabilities. In contrast, infected DCs, which express lower costimulatory molecules and higher levels of IL-10, promote the development of Leishmania Ag-specific, nonprotective T-bet(+)IFN-gamma(+)IL-10(+) CD4(+) T cells with an effector phenotype. This specific polarization was found to be dependent on IL-12p70. Splenic infected DCs recovered from chronic infected animals are similarly capable to polarize ex vivo syngeneic naive CD4(+) T cells toward a T-bet(+)IFN-gamma(+)IL-10(+) phenotype. Further analysis revealed that only MHC class II(high)-infected DCs were responsible for this polarization. The adoptive transfer of such polarized CD4(+) T cells facilitates visceral leishmaniasis in BALB/c mice in a clear contrast with their counterpart generated with bystander DCs that significantly potentiate protection. Further, we demonstrated that CD4(+) T cells primed by infected DCs in an IL-10 free system, thus deprived of T-bet(+)IFN-gamma(+)IL-10(+) population, restore the immune response and reduce parasite load, supporting a deleterious role of IFN-gamma(+)IL-10(+) T cells in the maintenance of infection. Overall, our results highlight novel subversion mechanisms by which nonprotective T-bet(+)IFN-gamma(+)IL-10(+) T cells are associated with chronicity and prolonged parasite persistence. |
