Antimouse CD52 monoclonal antibody inhibits established spontaneous colitis in IL-10-deficient mice

Treatment approaches to patients with multiple sclerosis and coexisting autoimmune disorders

The past decades have yielded major therapeutic advances in many autoimmune conditions - such as multiple sclerosis (MS) - and thus ushered in a new era of more targeted and increasingly potent immunotherapies. Yet this growing arsenal of therapeutic immune interventions has also rendered therapy much more challenging for the attending physician, especially when treating patients with more than one autoimmune condition. Importantly, some therapeutic strategies are either approved for several autoimmune disorders or may be repurposed for other conditions, therefore opening new curative possibilities in related fields. In this article, we especially focus on frequent and therapeutically relevant concomitant autoimmune conditions faced by neurologists when treating patients with MS, namely psoriasis, rheumatoid arthritis and inflammatory bowel diseases. We provide an overview of the available disease-modifying therapies, highlight possible contraindications, show pathophysiological overlaps and finally present which therapeutics can be utilized as a combinatory treatment, in order to 'kill two birds with one stone'.

Anti-mouse CD52 Treatment Ameliorates Colitis through Suppressing Th1/17 Mediated Inflammation and Promoting Tregs Differentiation in IL-10 Deficient Mice

Recent studies suggested that excessive T helper (Th)1/17 cells concomitant with regulatory T cell deficiency might play important roles in Crohn's disease. Anti-cluster of differentiation 52 (CD52) monoclonal antibody (mAb), which aims on CD52 antigen on mature immunocytes, has both T cell depletion and immunosuppressive activities. In this study, we evaluated the therapeutic effects and possible mechanisms of anti-CD52 treatment on interleukin-10 (IL-10) deficient mouse. Anti-mouse CD52 mAb was administered to C3H/HeJBir.IL-10^-/- (C3H.IL-10^-/-) mice intraperitoneally 20 µg per week for 2 weeks. The disease activity index, body weight, the histological grading of colitis, and levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, IL-17 and IL-6 in colon were quantified after treatment. In addition, CD25, Forkhead box P3 (Foxp3) and transforming growth factor (TGF)-β gene as well as the percentage of CD25⁺Foxp3⁺ T cells in colon were also measured. The severity of colitis in IL-10^-/- mice was significantly decreased by the treatment, with improvement of colon histological grade. The treatment also decreased the TNF-α, IFN-γ, IL-17 and IL-6 levels in colon. Furthermore, the treatment up-regulated the mRNA expression of CD25, Foxp3 and TGF-β gene as well as the percentage of CD25⁺Foxp3⁺ T cells in colon lamina propria mononuclear cells (LPMCs) of IL-10^-/- mice. Our data might indicate that anti-CD52 treatment could ameliorate the colitis of C3H.IL-10^-/- mice and it might be related to the suppression of Th1/17 related inflammation and the promotion of regulatory T cell differentiation. Thus, our data reveals that anti-CD52 treatment may hold potential for clinical applications for Crohn's disease treatment.

Anti-mouse CD52 monoclonal antibody ameliorates intestinal epithelial barrier function in interleukin-10 knockout mice with spontaneous chronic colitis

Intestinal inflammation causes tight junction changes and death of epithelial cells, and plays an important role in the development of Crohn's disease (CD). CD52 monoclonal antibody (CD52 mAb) directly targets the cell surface CD52 and is effective in depleting mature lymphocytes by cytolytic effects in vivo, leading to long-lasting changes in adaptive immunity. The aim of this study was to investigate the therapeutic effect of CD52 mAb on epithelial barrier function in animal models of IBD. Interleukin-10 knockout mice (IL-10(-/-) ) of 16 weeks with established colitis were treated with CD52 mAb once a week for 2 weeks. Severity of colitis, CD4(+) lymphocytes and cytokines in the lamina propria, epithelial expression of tight junction proteins, morphology of tight junctions, tumour necrosis factor-α (TNF-α)/TNF receptor 2 (TNFR2) mRNA expression, myosin light chain kinase (MLCK) expression and activity, as well as epithelial apoptosis in proximal colon were measured at the end of the experiment. CD52 mAb treatment effectively attenuated colitis associated with decreased lamina propria CD4(+) lymphocytes and interferon-γ/IL-17 responses in colonic mucosa in IL-10(-/-) mice. After CD52 mAb treatment, attenuation of colonic permeability, increased epithelial expression and correct localization of tight junction proteins (occludin and zona occludens protein-1), as well as ameliorated tight junction morphology were observed in IL-10(-/-) mice. CD52 mAb treatment also effectively suppressed the epithelial apoptosis, mucosa TNF-α mRNA expression, epithelial expression of long MLCK, TNFR2 and phosphorylation of MLC. Our results indicated that anti-CD52 therapy may inhibit TNF-α/TNFR2-mediated epithelial apoptosis and MLCK-dependent tight junction permeability by depleting activated T cells in the gut mucosa.

Anti-mouse CD52 monoclonal antibody ameliorates iron-deficient anaemia in IL-10 knockout mice

Approximately 50 % of patients with inflammatory bowel disease (IBD) suffer from anaemia, with Fe deficiency being the most common cause. CD52 monoclonal antibody (mAb) targets the cell surface CD52 and is effective in depleting lymphocytes through cytolytic effects in vivo. The aim of the present study was to investigate the therapeutic effect of anti-mouse CD52 mAb on Fe-deficient anaemia in IBD. IL-10 knockout mice (IL-10− / −) of 12 weeks with established colitis were treated with anti-mouse CD52 mAb once per week for 2 weeks. Severity of colitis, blood T lymphocytes, blood Hb, haematocrit, plasma erythropoietin (EPO), serum Fe concentration, transferrin saturation, splenic Fe stores, expression of liver hepcidin mRNA, Western blotting of the phosphorylated form of Smad1/5/8 and total Smad1 were measured at the end of the experiment. IL-10− / − mice treated with CD52 mAb showed a reduction in the percentage of CD4+ and CD4+CD45+ T cells in blood and weight loss typically associated with colonic inflammation, serum levels of EPO, the expression of liver hepcidin mRNA and total Smad1 protein, while they showed an increase in Hb concentrations, haematocrit, levels of serum Fe, transferrin saturation and splenic Fe stores. The present results indicated that anti-CD52 therapy may ameliorate Fe-deficient anaemia by reducing colonic inflammation. These findings may open novel horizons in the treatment of patients with IBD by resetting of immunological homeostasis in the gut by depleting the activated T cells in the gut mucosa.