Mast cells are critical promoters of adaptive immunity in the contact hypersensitivity model. but the mechanism of allergen sensitization is poorly understood. Using Mcpt5-CreTNFFL/FL mice. we show here that the absence of TNF exclusively in mast cells impaired the expansion of CD8+ T cells upon sensitization and the T-cell-driven adaptive immune response to elicitation. https://jalyttlers.shop/product-category/early-learning-toy/