006 Conventional dendritic cell 2 as an activator for cytotoxic T lymphocytes in the elicitation phase of murine contact hypersensitivity

Cytotoxic T lymphocyte (CTL) has been found to be activated by cutaneous dendritic cell (DC) in inducible skin-associated lymphoid tissue (iSALT) a murine contact hypersensitivity (CHS) model. Cutaneous DCs are classified into Langerhans (LC), conventional DC1 (cDC1), DC2 (cDC2) and monocyte-derived DC (MoDC); however, which subsets activate CTL within iSALT during the elicitation phase of CHS remained unclear. To clarify this, we used Langerin-diphtheria toxin receptor (DTR), XCR1-DTR CD301b-DTR mice deplete LC, cDC1 cDC2, respectively. remove MoDC, anti-CCR2 depleting antibody. Mice were sensitized applying 0.5% 2,4-dinitrofluorobenzene (DNFB) abdominal skin (day 0). Following administration diphtheria or antibody, elicited 0.3% DNFB ear 5). After 24 hours, swelling interferon-gamma (IFN-γ) production from significantly attenuated depletion cDC2 MoDC. However, there no significant differences LC cDC1. Immunohistochemical analysis revealed that cluster formation was suppressed but not In addition, colocalized with clusters. Taken together, these results suggest CHS. Further study elucidate molecular mechanism interaction between will provide new therapeutic strategies for CTL-mediated diseases.