α‐GalCer, a specific and potent stimulant for iNKT cells, can activate iNKT cells to promote the production of Th1 and Th2 cytokines, such as IL‐4, IL‐13 and IFN‐γ, and thereby modulate a diverse array of immune‐related diseases, including autoimmune disorders, tumour and infection.5, 6, 7 Many studies use mouse models of iNKT cell deficiency to investigate the role of iNKT cells. This evidence concerns the gene IL4 and neoplasm.