Plasmid encoding interferon-gamma exacerbates reovirus type-2-induced diabetes in DBA/1 suckling mice

Synthetic CpG oligodeoxynucleotides accelerate the development of lupus nephritis during preactive phase in NZB x NZWF1 mice

The effect of synthetic CpG-oligodeoxynucleotides (CpG-ODN) on the development of lupus nephritis during preactive phase (within seven months of age) in autoimmune lupus NZB x NZWF1 (B/WF1) mice was examined. Treatment of CpG-ODN was started at the age of 2.75 months and continued until 6.25 months. Overt disease began at the age of six months and progressed linearly at the age of 6.75 months in CpG-ODN-treated, but not control ODN-treated (control) groups. Also compared to control group, CpG-ODN-treated mice exhibited a severe glomerulonephritis (GN), with prominent deposits of IgG2a and C3, which paralleled increased titre of IgG2a type anti-nuclear antibody in the blood. Among several cytokines (interleukin, IL-6, IL-4, IL-1alpha, IL-10, interferon-gamma and tumor necrosis factor-alpha) in blood, IL-6 production paralleled the development of lupus nephritis. The present study suggests that CpG-ODN may enhance IL-6 production. The role of IL-6 in the development of GN will be discussed.

Interleukin-4-expressing plasmid DNA inhibits reovirus type-2-triggered autoimmune insulitis in DBA/1 J suckling mice

In this study we have examined the effect of systemic administration of T helper (Th) 2 cytokines on reovirus type-2 (Reo-2)-triggered Th1-mediated autoimmune insulitis with impaired glucose tolerance (IGT) in DBA/1J suckling mice. We have demonstrated clearly that the systemic administration of both interleukin (IL)-4-expressing plasmid DNA (pIL-4) and recombinant IL-4 (rIL-4) inhibited the development of insulitis with IGT in a dose dependent manner as compared to untreated groups in Reo-2-infected DBA/1J suckling mice. The inhibitory effects of IL-4 on the development of insulitis with IGT and the advantages of pIL-4 as compared to rIL-4 in this model are discussed.

CpG oligodeoxynucleotides accelerate reovirus type 2-triggered insulitis in DBA/1 suckling mice

We reported previously that reovirus type-2 (Reo-2) triggers T-helper (Th) 1-mediated autoimmune insulitis resulting in temporal impaired glucose tolerance (IGT) approximately 10 days post infection (d.p.i) in suckling DBA/1 mice. We hypothesized that CpG motifs in bacteria may enhance virus-induced insulitis through its content of unmethylated CpG motifs. In the infected mice, the intraperitoneal treatment of synthetic 20-base oligodeoxynucleotides with CpG motifs (CpG ODN) caused increase in cumulative incidence of insulitis with IGT, increased serum interferon (IFN)-gamma concentration, and high frequency of autoantibody against pancreatic islet cells, compared to the infected mice without CpG ODN at 17 d.p.i. Also CD4+ and CD8+ lymphocytes infiltrated in and/or around pancreatic islets in the CpG ODN-treated mice. This evidence suggests that CpG ODN may contribute to accelerate Reo-2-induced autoimmune reaction against pancreatic islet cells via additional effects of Th1 cytokines especially IFN-gamma.