Activated liver dendritic cells generate strong acquired immunity in α-galactosylceramide treatment

Background/Aims α-Galactosylceramide (α-GalCer) presented by dendritic cells (DCs) activates NKT cells that in turn drive DC maturation. However, the potential of generating acquired immunity of liver DCs in α-GalCer treatment remains unclear. Methods We examined the activation of acquired immunity in the α-GalCer treatment against liver or spleen tumor and the ability of liver and spleen DCs in the generation of acquired immunity. Results Administration of α-GalCer resulted in generation of p53 peptide-specific cytotoxic T lymphocytes (CTLs) in mice bearing liver CMS4 tumor, aberrantly expressing p53, but not in mice bearing spleen CMS4 tumor. The growth of rechallenged CMS4 subcutaneous tumor was inhibited in α-GalCer-treated mice against liver CMS4 tumor, but not in α-GalCer-treated mice against CMS4 spleen tumor. The antigen presenting related functions of liver DCs were significantly higher than those of spleen DCs in α-GalCer-treated mice. Vaccination of normal mice with p53 peptide pulsed liver DCs isolated from α-GalCer treated mice resulted in generation of p53 peptide-specific CTLs, but that with p53 peptide pulsed spleen DCs did not. Conclusions These results demonstrated that α-GalCer treatment induced unique immunologic activation of liver DCs in comparison with spleen DCs, which might be favorable to generate liver acquired immunity.