Transcutaneous immunization with a highly active form of XCL1 as a vaccine adjuvant using a hydrophilic gel patch elicits long-term CD8 T cell responses.

Memory CD8 cytotoxic T-lymphocytes (CTLs) play a key role in protective immunity against infection and cancer. However, the induction of memory CTLs with currently available vaccines remains difficult. The chemokine receptor XCR1 is predominantly expressed on CD103 cross-presenting dendritic cells (DCs).