036 Unique proteins appear at different times during the course of a delayed-type hypersensitivity reaction in human skin

Diphencyprone (DPCP) is a hapten that induces delayed-type hypersensitivity (DTH) reactions and used therapeutically for various conditions including alopecia areata melanoma metastases. Prior work has shown gene expression markers of major T cell subsets (Th1, Th2, Th17) are significantly increased at 3 days after single application DPCP in healthy volunteers. We evaluated the cutaneous proteome skin eight volunteers 3, 14, 120 application. assessed 96 proteins using Olink immuno-oncology panel. Compared to placebo-treated sites, DPCP-challenged (peak clinical inflammation) had 68 deregulated (P<0.05). At 14 (during resolution inflammation), 63 were (when inflammation completely resolved), no deregulated. 15 day but not 10 53 both Pathways upregulated progressively decreased with time, included: promoting tumor immunity, apoptosis/cell killing, inhibitory checkpoints, suppressing chemotaxis, vascular tissue remodeling, Th1, Th17 IL12 was only thus potentially directing Th1 intensification over time repeated as done therapeutically. As many all differentially expressed distinct points studied, uniquely during course DTH reaction may function polarize or resolve inflammation. The marked proteomic changes suggest duration human recall response defined antigen be more prolonged than suggested by current model systems.