CD4 and asthma: The atopic march refers to the development of atopic dermatitis during infancy and subsequent asthma in later childhood, and the skin is considered to be an important route for allergen sensitization.37 Although previous studies suggested that DCs, basophils, CD4 + T cells, and ILC2s were the potential targets of TSLP, there was no systematic analysis.15–26 We analyzed lineage-specific TSLPR-deficient mice revealing that both DCs and CD4 + T cells were the major responders to TSLP, and that they enhanced the induction of allergen-specific Th2 cells during the sensitization phase in vivo.