CD1d and CD1d-restricted iNKT-cells play a pivotal role in contact hypersensitivity

: CD1d‐restricted T‐cells are activated by glycolipids presented by the major histocompatibility complex class‐Ib molecule CD1d, found on the surface of antigen‐presenting cells (APC). This interaction between APC, most notably dendritic cells (DC), and CD1d‐restricted T‐cells is an important regulatory step in the initiation of adaptive immune responses. It is well known that DC play a crucial role in the induction of contact hypersensitivity (CHS), a frequently studied form of in vivo T‐cell‐mediated immunity. In this study, we show that CD1d‐restricted T‐cells are also necessary for CHS, because both wild‐type mice treated systemically or topically with CD1d glycolipid antagonists and CD1d‐restricted T‐cell‐null mice have markedly diminished CHS responses. Thus, pharmacologic antagonists of CD1d can be used as effective inhibitors of CHS, a prototype for a variety of delayed‐type tissue hypersensitivity responses.