Amelioration of experimental autoimmune uveoretinitis by pretreatment with a pathogenic peptide in liposome and anti-CD40 ligand monoclonal antibody.

We have defined a peptide K2 (ADKDVVVLTSSRTGGV) that corresponds to residues 201-216 of bovine interphotoreceptor retinoid-binding protein and induces experimental autoimmune uveoretinitis (EAU)4 in H-2Ak-carrying mice (H-2Ak mice). In this study, we attempted to ameliorate EAU in the H-2Ak mice without nonspecific suppression of T cell responses. Preceding s.c. administration of liposomes including K2 (liposomal K2) specifically inhibited subsequent generation of T cell response to K2. The same result was obtained with a combination of OVA323-339 peptide and the OVA-specific TCR-transgenic T cells. It was suggested that the inhibition was mainly attributed to peripheral anergy induction of T cells specific for the peptide Ag, although specific cell death might also be involved in the inhibition. Pretreatment with liposomal K2 also considerably abolished IFN-gamma production but not IL-4 production. The specific inhibitory effect of the pretreatment with liposomal peptide was augmented by a simultaneous administration of anti-CD40 ligand (anti-CD40L) mAb. Moreover, it was shown that the pretreatment with liposomal K2 reduced both the incidence and severity of the subsequent K2-induced EAU, and the simultaneous administration of anti-CD40L mAb augmented this preventive effect by liposomal K2. Our findings demonstrate that the s.c. administration of liposomal pathogenic peptide and anti-CD40L mAb can be applied to preventing autoimmune diseases without detrimental nonspecific suppression of T cell responses.