| First Author | Ballesteros-Tato A | Year | 2013 |
| Journal | J Exp Med | Volume | 210 |
| Issue | 8 | Pages | 1591-601 |
| PubMed ID | 23835849 | Mgi Jnum | J:202249 |
| Mgi Id | MGI:5517739 | Doi | 10.1084/jem.20130097 |
| Citation | Ballesteros-Tato A, et al. (2013) CD4+ T helper cells use CD154-CD40 interactions to counteract T reg cell-mediated suppression of CD8+ T cell responses to influenza. J Exp Med 210(8):1591-601 |
| abstractText | CD4(+) T cells promote CD8(+) T cell priming by licensing dendritic cells (DCs) via CD40-CD154 interactions. However, the initial requirement for CD40 signaling may be replaced by the direct activation of DCs by pathogen-derived signals. Nevertheless, CD40-CD154 interactions are often required for optimal CD8(+) T cell responses to pathogens for unknown reasons. Here we show that CD40 signaling is required to prevent the premature contraction of the influenza-specific CD8(+) T cell response. CD40 is required on DCs but not on B cells or T cells, whereas CD154 is required on CD4(+) T cells but not CD8(+) T cells, NKT cells, or DCs. Paradoxically, even though CD154-expressing CD4(+) T cells are required for robust CD8(+) T cell responses, primary CD8(+) T cell responses are apparently normal in the absence of CD4(+) T cells. We resolved this paradox by showing that the interaction of CD40-bearing DCs with CD154-expressing CD4(+) T cells precludes regulatory T cell (T reg cell)-mediated suppression and prevents premature contraction of the influenza-specific CD8(+) T cell response. Thus, CD4(+) T helper cells are not required for robust CD8(+) T cell responses to influenza when T reg cells are absent. |
