This is an interventional (a treatment given during the course of a research study) and multicenter (when more than one hospital or medical school team work on a medical research study) study. The study will consist of 3 Phases: Screening Phase (Up to 4 weeks), Data Collection Phase (9 days) and, Follow-up Phase (7 days). The maximum study duration for each participant will not exceed 43 days. Primarily, the cell populations and inflammatory mediator responses in suction skin blister fluid after allergic skin reaction (ASR) will be assessed. Participants' safety will be monitored throughout the study.