On the other hand, there is evidence that IL-4 exerts a dominant-negative effect on the progression to IDDM in non-obese diabetic (NOD) mice (45–47), and NOD mice with the mVα14-Jα18 transgene were protected from diabetes (48), indicating that not only the number but also the phenotype of iNKT cells influences the incidence of diabetes both in humans and mice. This evidence concerns the gene IL4 and diabetes mellitus.