On the other hand, the IL-4 levels produced by ConA and anti-CD3-stimulated liver MNCs were significantly reduced in the α-GalCer group, suggesting the suppression of Th2 immune responses. A predominant Th2 cytokine response in human membranous lupus nephritis has been reported33, and important roles for the Th2 immune responses in the pathogenesis of membranous lupus nephritis have been suggested34,35. Therefore, the present study strongly supported that the repeated administration of α-GalCer ameliorated the progression of lupus nephritis through the suppression of Th2 immune responses. However, it has also been reported that an α-GalCer injection modulates immune responses towards a Th2 phenotype in B6 mice36 and that Th2-biased immune responses induced by the administration of α-GalCer17,18 or its derivative37 prevented diabetes in NOD mice. Thus, the effects of α-GalCer could vary depending on the disease model.