SUMMARY Despite significant research and investment, no FDA approved broad spectrum countermeasures are available to rapidly mitigate vesicant-induced injury following intentional or accidental chemical exposure. Inflammatory pathways are a promising shared target for therapeutic intervention as: (1) inflammatory mechanisms may be conserved across multiple vesicants as inflammatory damage is present in all types of burns; (2) burn injury is not static, inflammatory damage continues to occur up to 72 hours after exposure and there is potential to arrest inflammatory damage and necrosis with early anti-inflammatory intervention; and (3) there is an existing portfolio of anti-inflammatory therapies and an active drug development pipeline that can be applied and optimized. Current approaches to investigate inflammatory mechanisms in skin lack integration of mechanistic and spatial information. Systemic fluid readouts may not accurately reflect local burn response and all spatial information is lost when skin biopsies are homogenized for traditional omics analyses. Histological analysis of biopsies can provide spatial information regarding tissue damage but lacks mechanistic insight. Therefore, novel spatial omics approaches that provide in situ understanding of the pathological response will be important tools in the discovery and development of medical countermeasures to vesicant-induced damage. The long-term objective of this research is to implement and establish a state-of-the-art spatial multi-omics platform to investigate conserved mechanisms of inflammatory damage induced by cutaneous exposure of sulfur mustard and lewisite vesicants in a clinically relevant porcine skin model. Utilizing innovative methods in spatial mass spectrometry, MALDI mass spectrometry imaging (MALDI-MSI), immunohistochemistry, and spatial transcriptomics we will map the distribution of transcriptional pathways and biomediators associated with localized vesicant-induced skin damage. The specific aims of this study are to 1) Identify the inflammatory phenotypes induced in response to dermal exposure to sulfur mustard and lewisite; and 2) Use high resolution spatial transcriptomics integrated with MALDI-MSI and immunohistochemistry to identify pathologic programs conserved across sulfur mustard and lewisite burn lesions. Our proposed spatial mapping approach will allow us to decipher the local inflammatory pathological effects of vesicants not evident in systemic studies and thus elucidate conserved pathologic inflammatory pathways that drive tissue damage and can be targeted for the development of medical countermeasures.