Functional Blocking Monoclonal Antibodies against IL-12p40 Homodimer Inhibit Adoptive Transfer of Experimental Allergic Encephalomyelitis

Abstract

IL-12p70 (p40:p35) and IL-23 (p40:p19) are bioactive cytokines and their role in experimental allergic encephalomyelitis (EAE), an animal model for multiple sclerosis, are becoming clear. On the other hand, the IL-12p40 homodimer (p402) was considered as an inactive or inhibitory molecule and its functions are poorly understood. To facilitate the studies on p402, we have recently generated neutralizing mAb against mouse p402. The present study demonstrates the effectiveness of p402 mAb in treating the disease process of relapsing-remitting EAE in female SJL/J mice. The p402 mAb ameliorated clinical symptoms and disease progression of EAE in recipient mice and suppressed the generation of encephalitogenic T cells in donor mice. Histological and blood-brain barrier (BBB) and blood-spinal cord barrier (BSB) permeability studies reveal that p402 mAb effectively inhibited the infiltration of mononuclear cells into brain and spinal cord and improved the integrity of BBB and BSB in EAE mice. Consequently, p402 mAb also suppressed the expression of proinflammatory molecules, normalized the expression of myelin genes, and blocked demyelination in the CNS of EAE mice. On the other hand, recombinant mouse p402 increased the infiltration of mononuclear cells into the CNS, enhanced the permeability through BBB and BSB, stimulated CNS expression of proinflammatory molecules, and aggravated the disease process of EAE. Taken together, our results suggest that p402 participates in the pathogenesis of EAE and that neutralization of p402 may be beneficial in multiple sclerosis patients.

Gemfibrozil, a Lipid-lowering Drug, Increases Myelin Genes in Human Oligodendrocytes via Peroxisome Proliferator-activated Receptor-β

“…11C). Earlier we have demonstrated a decrease in myelin gene expression in CNS tissues of EAE mice (28,30). Accordingly, here we also saw decreased protein levels of PLP and MOG in the spinal cord of PLP-TCR Tg mice compared with the non-Tg control (Fig.…”

“…Staining for Myelin-Spinal cord sections were stained with Luxol fast blue for myelin as described earlier (28,30). Slides were assessed in a blinded fashion for demyelination by three examiners using the following scale: 0, normal white matter; 1, rare foci; 2, a few areas of demyelination; and 3, large areas of demyelination.…”

Regulation of Encephalitogenicity of Neuroantigen-Primed T Cells by Nitric Oxide: Implications for Multiple Sclerosis

“…After perfusion with PBS (pH 7.4) and then with 4% (w/v) paraformaldehyde solution in PBS, cerebellum and whole spinal cord were dissected out from each mouse. The tissues were further fixed and then divided into two halves: one-half was used for histology analysis whereas the other half was used for myelin staining as described earlier (10)(11)(12)(13). For histological analysis, routine histology was performed to obtain perivascular cuffing and morphological details of cerebellar tissues of different groups of mice.…”

“…MBP-specific T cells were isolated and EAE was induced in 4-6 week old naïve female SJL/J mice (Harlan Sprague-Dawley (Indianapolis, IN) by adoptive transfer as described earlier (10)(11)(12)(13). Briefly, donor mice were immunized s.c. with 400 µg bovine MBP and 60 µg M. tuberculosis in IFA.…”

“…Semi-quantitative RT-PCR was carried out as described earlier (11-13) using a RT-PCR kit from Clontech. Briefly, 1 µg of total RNA was reverse transcribed using oligo(dT) [12][13][14][15][16][17][18] as primer and MMLV reverse transcriptase (Clontech) in a 20 µl reaction mixture. The resulting cDNA was appropriately-diluted, and diluted cDNA was amplified using Titanium Taq DNA polymerase and following primers.…”