This Phase 1 split-site pilot study will evaluate the safety and dermal tolerability of a topical exosome-containing liquid in 10 healthy adult volunteers. The investigational liquid will be applied to a small defined area of intact skin. A vehicle liquid without exosomes may be applied to a matched contralateral skin site as a control. The study will assess local skin reactions, systemic adverse events, vital signs, clinical laboratory parameters, and feasibility of topical administration. No burn wound or artificial skin wound will be induced in participants in this Phase 1 safety study.