The STAR Study: a real-world, international, observational study of the safety and tolerability of, and adherence to, serum-free subcutaneous interferon ß-1a in patients with relapsing multiple sclerosis.

BACKGROUND: Adverse reactions, particularly injection site reactions (ISRs), are common reasons for nonadherence to injectable multiple sclerosis (MS) treatments. Adherence to MS treatment is important to ensure good treatment outcomes. OBJECTIVE: The aim of this study was to assess the local tolerability of subcutaneous (SC) serum-free interferon (IFN) ß-1a in patients with relapsing MS over 1 year in a real-life, international setting. The study also assessed safety, disease activity, and adherence. METHODS: This was a prospective, international, multicenter, observational study of 251 patients with relapsing-remitting MS treated with SC serum-free IFN ß-1a 44 µg or 22 µg 3 times weekly for 12 months or until early discontinuation. The primary end point was the proportion of patients with ISRs. Secondary end points included proportion of patients with adverse events (AEs); annualized relapse rate (ARR); proportion of patients remaining relapse-free; and adherence to treatment. RESULTS: During the observation period, 27.5% (69 of 251) of patients experienced nonserious ISRs, which was consistent with the incidence reported in clinical studies. Five patients discontinued treatment and 2 patients suspended treatment because of ISRs. Mean age was 35.8 years; patients were predominantly white (94.8%), and two thirds (66.1%) were female. The overall incidence of AEs was 63.7% (160 of 251), and overall safety and tolerability were assessed as excellent, very good, or good in >85% of patients. More than 70% of patients remained relapse-free, and the mean ARR was 0.4. More than 90% of patients had very good or good adherence to treatment; a significantly greater proportion of these were relapse-free at 12 months compared with those with fair or poor adherence (77.6% vs 50.0%; P = 0.0107), and their ARR was significantly lower (0.3 vs 0.9; P = 0.0055). Patients with fair or poor adherence had 4.6 times higher odds of experiencing a relapse than those with very good or good adherence. CONCLUSIONS: The incidence of ISRs and the overall safety profile in this observational study, in an international population in a real-life setting, confirm the good local tolerability of SC serum-free IFN ß-1a reported in clinical studies. The association between good adherence and a lower ARR underlines the importance of good adherence. The good local and general tolerability of SC IFN ß-1a may help ensure a high level of adherence, which is associated with better clinical outcomes. ClinicalTrials.gov identifier: NCT01080027.

CD44 variant isoforms control experimental autoimmune encephalomyelitis by affecting the lifespan of the pathogenic T cells.

CD44 variant (CD44(v)) isoforms play important roles in the development of autoimmune disorders, including colitis and arthritis, but their role in multiple sclerosis (MS) has been explored only to a limited extent. We determined the functional relevance of CD44(v) isoforms in MS and its animal model, experimental autoimmune encephalomyelitis (EAE). Genetic ablation of CD44(v7) and CD44(v10) isoforms significantly reduced the clinical EAE burden, as well as the number of inflammatory infiltrates. CD44(v7) and CD44(v10) expression on both memory T and antigen-presenting cells, participated in the development of adoptive transfer EAE. Significantly reduced mRNA expression of Th1 signature genes was detected in the brains of CD44(v10-/-) mice compared with those of CD44(WT) mice. Furthermore, forkhead transcription factor 3 (Foxp3), Bcl-2, and inducible nitric oxide synthase (iNOS) levels were reduced in CD44(v10-/-) brains, whereas active caspase-3 was elevated. Brain-infiltrating CD4(hi)CD44(v10+) T cells preceded EAE onset and paralleled disease severity in wild-type but not in CD44(v7-/-) and CD44(v10-/-) mice. CD44(v7) and CD44(v10) expression contributed to EAE by increasing the longevity of autoreactive CD4(hi)panCD44(hi) T cells. Accordingly, the absence of CD44(v7) and CD44(v10) led to increased apoptosis in the inflammatory infiltrates and reduced Th1 responses, resulting in marked disease reduction. Although absent in noninflamed human brains, we detected CD44(v3), CD44(v7), and CD44(v10) isoforms on glial cells and on perivascular infiltrating cells of MS lesions. We conclude that CD44(v7) and CD44(v10), expressed on autoreactive CD4(hi)panCD44(hi) T cells, are critically involved in the pathogenesis of classic EAE by increasing their life span. Targeting these short CD44(v) isoform regions may reduce inflammatory processes and clinical symptoms in MS.

Efficacy of vitamin D3 as add-on therapy in patients with relapsing-remitting multiple sclerosis receiving subcutaneous interferon ß-1a: a Phase II, multicenter, double-blind, randomized, placebo-controlled trial.

Recent studies have demonstrated the immunomodulatory properties of vitamin D, and vitamin D deficiency may be a risk factor for the development of MS. The risk of developing MS has, in fact, been associated with rising latitudes, past exposure to sun and serum vitamin D status. Serum 25-hydroxyvitamin D [25(OH)D] levels have also been associated with relapses and disability progression. The identification of risk factors, such as vitamin D deficiency, in MS may provide an opportunity to improve current treatment strategies, through combination therapy with established MS treatments. Accordingly, vitamin D may play a role in MS therapy. Small clinical studies of vitamin D supplementation in patients with MS have reported positive immunomodulatory effects, reduced relapse rates and a reduction in the number of gadolinium-enhancing lesions. However, large randomized clinical trials of vitamin D supplementation in patients with MS are lacking. SOLAR (Supplementation of VigantOL(®) oil versus placebo as Add-on in patients with relapsing-remitting multiple sclerosis receiving Rebif(®) treatment) is a 96-week, three-arm, multicenter, double-blind, randomized, placebo-controlled, Phase II trial (NCT01285401). SOLAR will evaluate the efficacy of vitamin D(3) as add-on therapy to subcutaneous interferon beta-1a in patients with RRMS. Recruitment began in February 2011 and is aimed to take place over 1 calendar year due to the potential influence of seasonal differences in 25(OH)D levels.

CD97 in leukocyte trafficking.

CD97 is a member of the EGF-TM7 family of adhesion G protein-coupled receptors (GPCRs) broadly expressed on leukocytes. CD97 interacts with several cellular ligands via its N-terminal epidermal growth factor (EGF)-like domains. To understand the biological function of CD97, monoclonal antibodies (mAbs) specific for individual EGF domains have been applied in a variety of in vivo models in mice, which represent different aspects of innate and adaptive immunity. Targeting CD97 by mAbs inhibited the accumulation of neutrophilic granulocytes at sites of inflammation thereby affecting antibacterial host defense, inflammatory disorders and stem cell mobilization from bone marrow. Interestingly, targeting CD97 did not impact antigen-specific (adaptive response) models such as delayed type hypersensitivity (DTH) or experimental autoimmune encephalomyelitis (EAE). However, collagen-induced arthritis (CIA), a model for rheumatoid arthritis, was significantly ameliorated suggesting therapeutic value of CD97 targeting. CD97-deficient mice are essentially normal at steady state except for a mild granulocytosis, which increases under inflammatory conditions. Comparison of the consequences of antibody treatment and gene targeting implies that CD97 mAbs actively inhibit the innate response presumably at the level of granulocyte or macrophage recruitment to sites of inflammation. Based on the collected data, we propose that the CD97 mAbs either activate CD97-mediated signal transduction via a yet unknown mechanism or act by inducing CD97 internalization, making CD97 unavailable for binding to its ligands and thereby blocking recruitment of neutrophils and possibly macrophages.

Phagocytes containing a disease-promoting Toll-like receptor/Nod ligand are present in the brain during demyelinating disease in primates.

Recent studies claim a central role for Toll-like receptor (TLR) ligands in stimulating autoimmune disease by activation of antigen-presenting cells in the target organ, but it is unclear if and how TLR ligands reach target organs. Most evidence comes from rodent models, and it is uncertain whether this principle holds in primates. Here we identify which cells contain peptidoglycan (PGN) in multiple sclerosis brain and in two nonhuman primate experimental autoimmune encephalomyelitis (EAE) models with different disease courses: acute (rhesus monkey) versus chronic disease (marmoset). Because persistence of TLR ligands in the central nervous system might be consequential for disease progression, we also determined the expression of two major PGN-degrading enzymes, ie, lysozyme and N-acetylmuramyl-l-alanine amidase. Distinct phagocyte subsets, including granulocytes, macrophages, and dendritic cells, contained PGN in the brain and coexpressed the inflammatory cytokine interleukin-12. The number of phagocytes carrying PGN increased in acute and chronic EAE compared with control animals, with the highest number of PGN-containing cells in acute EAE brain. Lytic enzymes were scarcely expressed in monkey and multiple sclerosis brain, favoring PGN persistence. PGN stimulated interleukin-12p70 release by leukocytes from all three primate species. The presence of PGN in the inflamed brain may have major implications because TLR2/Nod ligation potentially promotes inflammation and disease progression.

Proinflammatory bacterial peptidoglycan as a cofactor for the development of central nervous system autoimmune disease.

Upon stimulation by microbial products through TLR, dendritic cells (DC) acquire the capacity to prime naive T cells and to initiate a proinflammatory immune response. Recently, we have shown that APC within the CNS of multiple sclerosis (MS) patients contain peptidoglycan (PGN), a major cell wall component of Gram-positive bacteria, which signals through TLR and NOD. In this study, we report that Staphylococcus aureus PGN as a single component can support the induction of experimental autoimmune encephalomyelitis (EAE) in mice, an animal model for MS. Mice immunized with an encephalitogenic myelin oligodendrocyte glycoprotein peptide in IFA did not develop EAE. In contrast, addition of PGN to the emulsion was sufficient for priming of autoreactive Th1 cells and development of EAE. In vitro studies demonstrate that PGN stimulates DC-mediated processes, reflected by increased Ag uptake, DC maturation, Th1 cell expansion, activation, and proinflammatory cytokine production. These data indicate that PGN-mediated interactions result in proinflammatory stimulation of Ag-specific effector functions, which are important in the development of EAE. These PGN-mediated processes may occur both within the peripheral lymph nodes as well as in the CNS and likely involve recognition by TLR on DC. Thus, PGN may provide a physiological trigger of DC maturation, and in this way disrupt the normal tolerance to self Ag. As such, PGN signaling pathways may serve as novel targets for the treatment of MS.

Reduced experimental autoimmune encephalomyelitis after intranasal and oral administration of recombinant lactobacilli expressing myelin antigens.

Oral administration of autoantigens is a safe and convenient way to induce peripheral T-cell tolerance in autoimmune diseases like multiple sclerosis (MS). To increase the efficacy of oral tolerance induction and obviate the need for large-scale purification of human myelin proteins, we use genetically modified lactobacilli expressing myelin antigens. A panel of recombinant lactobacilli was constructed producing myelin proteins and peptides, including human and guinea pig myelin basic protein (MBP) and proteolipid protein peptide 139-151 (PLP(139-151)). In this study we examined whether these Lactobacillus recombinants are able to induce oral and intranasal tolerance in an animal model for multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). Lewis rats received soluble cell extracts of Lactobacillus transformants intranasally three times prior to induction of EAE. For the induction of oral tolerance, rats were fed live transformed lactobacilli for 20 days. Ten days after the first oral administration EAE was induced. Intranasal administration of extracts containing guinea pig MBP (gpMBP) or MBP(72-85) significantly inhibited EAE in Lewis rats. Extracts of control transformants did not reduce EAE. Live lactobacilli expressing guinea pig MBP(72-85) fused to the marker enzyme beta-glucuronidase (beta-gluc) were also able to significantly reduce disease when administered orally. In conclusion, these experiments provide proof of principle that lactobacilli expressing myelin antigens reduce EAE after mucosal (intranasal and oral) administration. This novel method of mucosal tolerance induction by mucosal administration of recombinant lactobacilli expressing relevant autoantigens could find applications in autoimmune disease in general, such as multiple sclerosis, rheumatoid arthritis and uveitis.

Expression of the EGF-TM7 receptor CD97 and its ligand CD55 (DAF) in multiple sclerosis.

CD97 is a recently identified seven-span transmembrane (7-TM) protein that is expressed by leukocytes early after activation. CD97 binds to its cellular ligand CD55 (decay accelerating factor), which protects several cell types from complement-mediated damage. The functional consequences of CD97-CD55 binding are largely unknown, but previous data imply that CD97-CD55 interactions play a role in cellular activation, migration, and adhesion under inflammatory conditions. Here we examined the expression of CD97 and CD55 by immunohistochemistry in multiple sclerosis (MS). On the basis of established criteria for inflammation and demyelination, different lesion stages were distinguished in MS post-mortem brain tissue. In normal white matter, CD97 expression was not found, but CD55 was expressed with weak staining intensity on endothelial cells. In pre-active lesions, defined by abnormalities of the white matter, many infiltrating T cells, macrophages (MPhi) and microglia expressed CD97. CD55 was highly expressed by endothelial cells. In active lesions with myelin degradation, MPhi and microglia expressed both CD55 and CD97. Furthermore, a sandwich ELISA showed significantly (p<0.05) elevated levels of soluble CD97 in serum but not in cerebrospinal fluid of MS patients (37%) compared to healthy controls (8%).Collectively, these data suggest that CD97-CD55 interactions are involved in the inflammatory processes in MS. CD55, which is expressed in lesions by vessels to protect against complement-mediated damage, might bind to CD97 on infiltrating leukocytes. This interaction may facilitate cell activation and migration through the blood-brain barrier. In addition, CD97-CD55 interactions in the parenchyma of the brain may contribute to the inflammation.