Monoclonal antibodies in MS: mechanisms of action

People with Primary Progressive Multiple Sclerosis Have a Lower Number of Central Memory T Cells and HLA-DR+ Tregs

The importance of circulating immune cells to primary progressive multiple sclerosis (PPMS) pathophysiology is still controversial because most immunotherapies were shown to be ineffective in treating people with PPMS (pwPPMS). Yet, although controversial, data exist describing peripheral immune system alterations in pwPPMS. This study aims to investigate which alterations might be present in pwPPMS free of disease-modifying drugs (DMD) in comparison to age- and sex-matched healthy controls. A multicentric cross-sectional study was performed using 23 pwPPMS and 23 healthy controls. The phenotype of conventional CD4+ and CD8+ T cells, regulatory T cells (Tregs), B cells, natural killer (NK) T cells and NK cells was assessed. Lower numbers of central memory CD4+ and CD8+ T cells and activated HLA-DR+ Tregs were observed in pwPPMS. Regarding NK and NKT cells, pwPPMS presented higher percentages of CD56dimCD57+ NK cells expressing NKp46 and of NKT cells expressing KIR2DL2/3 and NKp30. Higher disease severity scores and an increasing time since diagnosis was correlated with lower numbers of inhibitory NK cells subsets. Our findings contribute to reinforcing the hypotheses that alterations in peripheral immune cells are present in pwPPMS and that changes in NK cell populations are the strongest correlate of disease severity.

Phase II trial of natalizumab for the treatment of anti-Hu associated paraneoplastic neurological syndromes

Background

Paraneoplastic neurological syndromes with anti-Hu antibodies (Hu-PNS) have a very poor prognosis: more than half of the patients become bedridden and median survival is less than 12 months. Several lines of evidence suggest a pathogenic T cell-mediated immune response. Therefore, we conducted a prospective open-label phase II trial with natalizumab.

Methods

Twenty Hu-PNS patients with progressive disease were treated with a maximum of three monthly natalizumab cycles (300 mg). The primary outcome measure was functional improvement, this was defined as at least one point decrease in modified Rankin Scale (mRS) score at the last treatment visit. In addition, treatment response was assessed wherein a mRS score ≤3 after treatment was defined as treatment responsive.

Results

The median age at onset was 67.8 years (SD 8.4) with a female predominance (n = 17, 85%). The median time from symptom onset to Hu-PNS diagnosis was 5 months (IQR 2–11). Most patients had subacute sensory neuronopathy (n = 15, 75%), with a median mRS of 4 at baseline. Thirteen patients had a tumor, all small cell lung cancer. After natalizumab treatment, two patients (10%) showed functional improvement. Of the remaining patients, 60% had a stable functional outcome, while 30% showed further deterioration. Treatment response was classified as positive in nine patients (45%).

Conclusions

Natalizumab may ameliorate the disease course in Hu-PNS, but no superior effects above other reported immunosuppressive and immunomodulatory were observed. More effective treatment modalities are highly needed.

Trial registration

https://www.clinicaltrialsregister.eu/ctr-search/trial/2014-000675-13/NL

Decreased Neurofilament L Chain Levels in Cerebrospinal Fluid and Tolerogenic Plasmacytoid Dendritic Cells in Natalizumab-Treated Multiple Sclerosis Patients - Brief Research Report

Background

Neurofilament Light (NfL) chain levels in both cerebrospinal fluid (CSF) and serum have been correlated with the reduction of axonal damage in multiple sclerosis (MS) patients treated with Natalizumab (NTZ). However, little is known about the function of plasmacytoid cells in NTZ-treated MS patients.

Objective

To evaluate CSF NfL, serum levels of soluble-HLA-G (sHLA-G), and eventual tolerogenic behavior of plasmacytoid dendritic cells (pDCs) in MS patients during NTZ treatment.

Methods

CSF NfL and serum sHLA-G levels were measured using an ELISA assay, while pDCs (BDCA-2⁺) were accessed through flow cytometry analyses.

Results

CSF levels of NfL were significantly reduced during NTZ treatment, while the serum levels of sHLA-G were increased. Moreover, NTZ treatment enhanced tolerogenic (HLA-G⁺, CD274⁺, and HLA-DR⁺) molecules and migratory (CCR7⁺) functions of pDCs in the peripheral blood.

Conclusion

These findings suggest that NTZ stimulates the production of molecules with immunoregulatory function such as HLA-G and CD274 programmed death-ligand 1 (PD-L1) which may contribute to the reduction of axonal damage represented by the decrease of NfL levels in patients with MS.

Update on infective complications in patients treated with alemtuzumab for multiple sclerosis: review and meta-analysis of real-world and randomized studies

OBJECTIVE

We aimed to systematically assess the pooled prevalence of infective complications in randomized controlled trials (RCTs) and real-world studies (RWSs) investigating alemtuzumab treatment in multiple sclerosis (MS), also looking at selected infections and their severity.

METHODS

We included in the analysis RCTs and RWSs investigating the use of alemtuzumab in MS in which infective complications were reported, as well as case reports of rare infections. We conducted a meta-analysis of proportions and a random effect model meta-regression to investigate heterogeneity.

RESULTS

The pooled prevalence of infective complications in alemtuzumab treated MS patients is 24%. The most common reported infections are respiratory tract infections (47%) and the most part of the infections are mild-to-moderate (85%). Severe infections account for 6% of the total estimate. We found first-time-reported cases of invasive aspergillosis, hepatitis E virus infection, EBV hepatitis, and cerebral toxoplasmosis. The prevalence of infections is higher in studies conducted before 2009, and in studies with higher proportion of male participants.

CONCLUSIONS

Clinicians should be aware that the prevalence of serious infections during alemtuzumab can be higher than expected from RCTs. Peculiar opportunistic infections should be considered when evaluating a patient treated with alemtuzumab who develops signs of infection.

An Overview of Therapeutic Options in Relapsing-remitting Multiple Sclerosis

Multiple sclerosis (MS) is a chronic disorder of the central nervous system (CNS). MS affects 2.1 million individuals every year and is also considered a major cause of economic health burden around the world. Genetics and environmental factors both play a role in the pathogenesis of MS by activating the immune response and causing inflammation. Patients with MS can have various clinical courses, but the most common pattern seen is relapsing-remitting multiple sclerosis (RRMS). Multiple therapeutic options have been studied to prevent RRMS patients from frequent relapses. The oldest and most frequently used medication for MS is interferon beta, either used alone or as add-on therapy with other drugs. Newer treatment options that have been recently approved to control MS symptoms and suppress the inflammation are glatiramer acetate and siponimod. Infusion therapies consisting of monoclonal antibodies and immunosuppressive drugs have also been studied in the recent past. Some trials have been conducted on the use of stem cells for RRMS patients. We have briefly discussed all treatment options and the response of RRMS patients in multiple trials.

Daclizumab Therapy for Multiple Sclerosis

Daclizumab is a humanized monoclonal antibody that prevents formation of high-affinity interleukin (IL)-2 receptor (IL-2R). Because activated T cells up-regulate high-affinity IL-2R and IL-2 is used to grow activated T cells in vitro, daclizumab was envisioned to selectively inhibit activated T cells. However, the mechanism of action (MOA) of daclizumab is surprisingly broad and it includes many unanticipated effects on innate immunity. Specifically, daclizumab modulates the development of innate lymphoid cells, leading to expansion of immunoregulatory CD56^bright natural killer (NK) cells. Activated CD56^bright NK cells migrate to the intrathecal compartment in multiple sclerosis (MS) and regulate autoreactive T cells via cytotoxicity. Finally, daclizumab also restricts initial steps of T-cell activation by blocking trans-presentation of IL-2 by dendritic cells to antigen-specific T cells. In conclusion, daclizumab has complex immunomodulatory effects with resultant inhibition of central nervous system inflammation in MS.

Intrathecal B Cells in MS Have Significantly Greater Lymphangiogenic Potential Compared to B Cells Derived From Non-MS Subjects

Although B cell depletion is an effective therapy of multiple sclerosis (MS), the pathogenic functions of B cells in MS remain incompletely understood. We asked whether cerebrospinal fluid (CSF) B cells in MS secrete different cytokines than control-subject B cells and whether cytokine secretion affects MS phenotype. We blindly studied CSF B cells after their immortalization by Epstein-Barr Virus (EBV) in prospectively-collected MS patients and control subjects with other inflammatory-(OIND) or non-inflammatory neurological diseases (NIND) and healthy volunteers (HV). The pilot cohort (n = 80) was analyzed using intracellular cytokine staining (n = 101 B cell lines [BCL] derived from 35 out of 80 subjects). We validated differences in cytokine production in newly-generated CSF BCL (n = 207 BCL derived from subsequent 112 prospectively-recruited subjects representing validation cohort), using ELISA enhanced by objective, flow-cytometry-based B cell counting. After unblinding the pilot cohort, the immortalization efficiency was almost 5 times higher in MS patients compared to controls (p < 0.001). MS subjects' BCLs produced significantly more vascular endothelial growth factor (VEGF) compared to control BCLs. Progressive MS patients BCLs produced significantly more tumor necrosis factor (TNF)-α and lymphotoxin (LT)-α than BCL from relapsing-remitting MS (RRMS) patients. In the validation cohort, we observed lower secretion of IL-1β in RRMS patients, compared to all other diagnostic categories. The validation cohort validated enhanced VEGF-C production by BCL from RRMS patients and higher TNF-α and LT-α secretion by BCL from progressive MS. No significant differences among diagnostic categories were observed in secretion of IL-6 or GM-CSF. However, B cell secretion of IL-1β, TNF-α, and GM-CSF correlated significantly with the rate of accumulation of disability measured by MS disease severity scale (MS-DSS). Finally, all three cytokines with increased secretion in different stages of MS (i.e., VEGF-C, TNF-α, and LT-α) enhance lymphangiogenesis, suggesting that intrathecal B cells directly facilitate the formation of tertiary lymphoid follicles, thus compartmentalizing inflammation to the central nervous system.

Risk of opportunistic infections in patients treated with alemtuzumab for multiple sclerosis

INTRODUCTION

Alemtuzumab is a monoclonal anti CD-52 antibody recently approved for use in relapsing-remitting multiple sclerosis(MS). Given that the targeted antigen is primarily expressed on B and T lymphocytes, the administration of this biological drug is associated with rapid but protracted peripheral lymphopenia.

AREAS COVERED

The impact on infective risk of this immune impairment is still to be fully understood. In this review, we attempt to summarize all the available literature concerning opportunistic infections occurring in patients with MS receiving alemtuzumab. Infective adverse events were observed in more than 70% of patients in phase 2/3 RCTs, mainly of mild-to-moderate severity. Nevertheless, several post-marketing reports documented cases of serious, rare, and unexpected infections.

EXPERT OPINION

Predictive risk factors and prognostic features of opportunistic infections in this setting still need to be exactly assessed. At present, the only recommended preventive measures consist in anti-herpetic prophylaxis, Listeria-free diet, Tuberculosis prophylaxis and annual Papillomavirus screening. Given the non-negligible risk of unpredicted infective events, we advise physicians to take into account patients' history of infectious diseases and vaccine status and to consider supplementary prophylactic strategies, including screening for Toxoplasma gondii and viral hepatitis serostatus as well as pre-emptive approaches to avert CMV reactivation and Pneumocystosis.

Pharmacokinetic drug evaluation of daclizumab for the treatment of relapsing-remitting multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system. Despite the availability of several disease-modifying therapies for relapsing MS, there is a need for highly efficacious targeted therapy with a favorable benefit-risk profile and a high level of treatment adherence. Daclizumab is a humanized monoclonal antibody directed against CD25, the α subunit of the high-affinity interleukin 2 (IL-2) receptor, that reversibly modulates IL-2 signaling. Areas covered: Daclizumab blocks the activation and expansion of autoreactive T cells that plays a role in the immune pathogenesis of MS. As its modulatory effects on the immune system, daclizumab's potential for use in MS was tested extensively showing a high efficacy in reducing relapse rate, disability progression and the number and volume of gadolinium-enhancing lesions on brain magnetic resonance imaging. Moreover, phase II and III trials showed a favorable pharmacokinetic (PK) profile with slow clearance, linear pharmacokinetics at doses above 100 mg and high subcutaneous bioavailability, not influenced by age, sex or other clinical parameters. Expert opinion: Among the new emerging drugs for MS, daclizumab also, thanks to a favorable PK profile, may represent an interesting and promising therapeutic option in the wide MS therapies armamentarium.

Alemtuzumab versus interferon beta 1a for relapsing-remitting multiple sclerosis

BACKGROUND

Alemtuzumab is a humanised monoclonal antibody that alters the circulating lymphocyte pool, causing prolonged lymphopenia, thus remoulding the immune repertoire that accompanies homeostatic lymphocyte reconstitution. It has been proved more effective than interferon (IFN) 1a for the treatment of relapsing-remitting multiple sclerosis (RRMS).

OBJECTIVES

To compare the efficacy, tolerability and safety of alemtuzumab versus interferon beta 1a in the treatment of people with RRMS to prevent disease activity.

SEARCH METHODS

We searched the Cochrane Multiple Sclerosis and Rare Diseases of the CNS Group Trials Register (1 February 2017) which, among other sources, contains records from CENTRAL, MEDLINE, Embase, CINAHL, LILACS, PEDRO and the trial registry databases Clinical Trials.gov and WHO International Clinical Trials Registry Platform for all prospectively registered and ongoing trials.

SELECTION CRITERIA

All double-blind, randomised, controlled trials comparing intravenous alemtuzumab (12 mg per day or 24 mg per day on five consecutive days during the first month and on three consecutive days at months 12 and 24) versus subcutaneous IFN beta 1a (22 μg or 44 μg three times per week (Rebif) or intramuscular injection 30 μg once a week (Avonex)) in people of any gender and age with RRMS.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included three trials involving 1694 participants. All trials compared alemtuzumab 12 mg per day or 24 mg per day versus IFN beta 1a for treating RRMS. In CAMMS223, participants received either subcutaneous IFN beta 1a 44 μg three times per week or annual intravenous cycles of alemtuzumab (at a dose of 12 mg per day or 24 mg per day) for 36 months. In CARE-MS I and CARE-MS II, participants received subcutaneous IFN beta 1a 44 μg three times per week or annual intravenous cycles of alemtuzumab 12 mg per day for 24 months. The methodological quality was good for all three studies.In the alemtuzumab 12 mg per day group, the results showed statistically significant difference in reducing relapses (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.52 to 0.70), preventing disease progression (RR 0.60, 95% CI 0.45 to 0.79) and developing new T2 lesions on magnetic resonance imaging (RR 0.75, 95% CI 0.61 to 0.93) after 24 and 36 months' follow-up, but found no statistically significant difference in the changes of Expanded Disability Status Scale (EDSS) score (mean difference (MD) -0.35, 95% CI -0.73 to 0.03). In the alemtuzumab 24 mg per day group, the results showed statistically significant differences in reducing relapses (RR 0.38, 95% CI 0.23 to 0.62), preventing disease progression (RR 0.42, 95% CI 0.21 to 0.84) and the changes of EDSS score (MD -0.83, 95% CI -1.17 to -0.49) after 36 months' follow-up.All three trials reported adverse events and serious adverse events. There was no statistically significant difference in the number of participants with at least one adverse event (RR 1.03, 95% CI 0.97 to 1.08) and the number of participants who experienced serious adverse events (RR 1.03, 95% CI 0.83 to 4.54).

AUTHORS' CONCLUSIONS

There is low- to moderate-quality evidence that annual intravenous cycles of alemtuzumab at a dose of 12 mg per day or 24 mg per day reduces the proportion of participants with relapses, disease progression, change of EDSS score and developing new T2 lesions on MRI over 24 to 36 months in comparison with subcutaneous IFN beta-1a 44 μg three times per week.Alemtuzumab appeared to be relatively well tolerated. The most frequently reported adverse events were infusion-associated reactions, infections and autoimmune events. The use of alemtuzumab requires careful monitoring so that potentially serious adverse effects can be treated early and effectively.

Lipopolysaccharide Binding Protein and Oxidative Stress in a Multiple Sclerosis Model

Recent findings in experimental autoimmune encephalomyelitis (EAE) suggest that altering certain bacterial populations present in the gut may lead to a proinflammatory condition, that could result in the development of multiple sclerosis (MS). Also, Reactive Oxygen Species seem to be involved in the course of MS. In this study, it has been aimed to relate all these variables starting from an analysis of the lipopolysaccharide (LPS) and LPS-binding protein (LBP) with the determination of parameters related to oxidative stress in the blood, brain and spinal cord. For this purpose, samples obtained from EAE rats and relapsing-remitting (RRMS) MS patients were used. In addition, EAE rats were treated with Natalizumab, N-acetyl-cysteine and dimethyl fumarate. Natalizumab was also employed in RRMS. The results of this study revealed an improvement in the clinical symptoms of the EAE and MS with the treatments, as well as a reduction in the oxidative stress parameters and in LBP. Correlations between the clinical variables of the disease, i.e. oxidative damage and LBP, were established. Although the conclusions of this research are indeed relevant, further investigation would be necessary to establish the intrinsic mechanisms of the MS-oxidative stress-microbiota relationship.

Spotlight on daclizumab: its potential in the treatment of multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory-demyelinating disease of the central nervous system of a putative autoimmune etiology. Although the exact pathogenic mechanisms underlying demyelination and axonal damage in MS are not fully understood, T-cells are believed to play a central role in the pathogenesis of the disease. Daclizumab is a humanized binding monoclonal antibody that binds to the Tac epitope on the α-subunit (CD25) of the interleukin-2 (IL-2) receptor, thus effectively blocking the formation of the high-affinity IL-2 receptor, which is expressed mainly on T-cells. A series of clinical trials in patients with relapsing MS demonstrated a profound effect of daclizumab on inflammatory disease activity and improved clinical outcomes compared with placebo or interferon-β, which led to the recent approval of daclizumab (Zinbryta™) for the treatment of relapsing forms of MS. Enhancement of endogenous mechanisms of immune regulation rather than inhibition of effector T-cells might explain the effects of daclizumab in MS. These include expansion and improved function of regulatory CD56bright NK cells, inhibition of the early activation of T-cells through blockade of IL-2 transpresentation by dendritic cells and reduction in the number of intrathecal proinflammatory lymphoid tissue inducer cells. The enhanced efficacy of daclizumab is accompanied by an increased frequency of adverse events and risks of serious adverse events, thus placing it as a second-line therapy and calling for the implementation of a strict risk management program. This review details the mechanisms of action of daclizumab, discusses its efficacy and safety in patients with MS, and provides an insight into the place of this novel therapy in the treatment of MS.

Absence of systemic oxidative stress and increased CSF prostaglandin F2α in progressive MS

OBJECTIVE

We aimed to investigate the role of oxidative stress in the progression of multiple sclerosis (MS).

METHODS

We determined by liquid chromatography-tandem mass spectrometry nonenzymatic (F2-isoprostanes) and enzymatic oxidation products of arachidonic acid (prostaglandin F2α [PGF2α]) in plasma and CSF of 45 controls (other neurologic disease [OND] with no signs of inflammation) and 62 patients with MS. Oxidation products were correlated with disease severity and validated biomarkers of inflammation (chemokine ligand 13; matrix metalloproteinase-9; osteopontin) and axonal damage (neurofilament light protein).

RESULTS

Compared with OND controls, plasma concentrations of F2-isoprostanes and PGF2α were significantly lower in patients with progressive disease, and decreased with increasing disability score (Expanded Disability Status Scale). In contrast, CSF concentrations of PGF2α, but not F2-isoprostanes, were significantly higher in patients with progressive disease than OND controls (p < 0.01). The content of PGF2α in CSF increased with disease severity (p = 0.044) and patient age (p = 0.022), although this increase could not be explained by age. CSF PGF2α decreased with natalizumab and methylprednisolone treatment and was unaffected by the use of nonsteroidal anti-inflammatory drug in secondary progressive MS. CSF PGF2α did not associate with validated CSF markers of inflammation and axonal damage that themselves did not associate with the Expanded Disability Status Scale.

CONCLUSIONS

Our data suggest that MS progression is associated with low systemic oxidative activity. This may contribute to immune dysregulation with CNS inflammation accompanied by increased local cyclooxygenase-dependent lipid oxidation.

Cytokine Profile in Patients with Progressive Multiple Sclerosis and Its Association with Disease Progression and Disability

Inflammation is the driving force for brain injury in patients with multiple sclerosis (MS). The objective of the present study is to delineate the serum cytokine profile in patients with progressive MS in a Southern Brazilian population compared with healthy controls and patients with relapsing-remitting MS (RRMS) and its associations with disease progression and disability. We included 32 patients with progressive MS, 126 with RRMS, and 40 healthy controls. The patients were evaluated using the Expanded Disability Status Scale (EDSS) and magnetic resonance imaging (MRI) with gadolinium. Serum interleukin (IL)-1β, IL-6, IL-12, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, IL-10, IL-4, and IL-17 levels were assessed using an enzyme-linked immunosorbent assay. IL-1β, IL-6, TNF-α, IFN-γ, IL-17, IL-4, and IL-10 levels were higher in progressive MS than in controls. Increased IL-1β and IFN-γ and decreased IL-12 and IL-4 levels were found in progressive MS compared with RRMS. Patients with progressive MS with disease progression presented higher TNF-α, IFN-γ, and IL-10 levels than those without disease progression. Patients with progressive MS with disease progression showed a higher frequency of positive gadolinium-enhanced lesions in MRI; higher TNF-α, IFN-γ, and IL-17 levels; and decreased IL-12 levels compared with RRMS patients with progression. There was a significant inverse correlation between IL-10 levels and EDSS score in patients with progressive MS. The results underscore the complex cytokine network imbalance exhibited by progressive MS patients and show the important involvement of TNF-α, IFN-γ, and IL-17 in the pathophysiology and progression of the disease. Moreover, serum IL-10 levels were inversely associated with disability in patients with progressive MS.

Recent Advances in Monoclonal Antibody Therapies for Multiple Sclerosis

INTRODUCTION

Multiple sclerosis (MS) is the most common chronic inflammatory, demyelinating disease of the CNS and results in neurological disability. Existing immunomodulatory and immunosuppressive approaches lower the number of relapses but do not cure or reverse existing deficits nor improve long-term disability in MS patients.

AREAS COVERED

Monogenic antibodies were described as treatment options for MS, however the immunogenicity of mouse antibodies hampered the efficacy of potential therapeutics in humans. Availability of improved antibody production technologies resulted in a paradigm shift in MS treatment strategies. In this review, an overview of immunotherapies for MS that use conventional monoclonal antibodies reactive to immune system and their properties and mechanisms of action will be discussed, including recent advances in MS therapeutics and highlight natural autoantibodies (NAbs) that directly target CNS cells.

EXPERT OPINION

Recent challenges for MS therapy are the identification of relevant molecular and cellular targets, time frame of treatment, and antibody toxicity profiles to identify safe treatment options for MS patients. The application of monoclonal antibody therapies with better biological efficacy associated with minimum side effects possesses huge clinical potential. Advances in monoclonal antibody technologies that directly target cells of nervous system may promote the CNS regeneration field from bench to bedside.

Multiple sclerosis increases the risk of venous thromboembolism: a nationwide cohort analysis

OBJECTIVES

The purpose of this study was to evaluate the effects of multiple sclerosis (MS) on the risk of venous thromboembolism (VTE) development.

METHODS

We identified patients diagnosed with MS in Taiwan between 1998 and 2010 using the National Health Insurance Research Database and the Catastrophic Illness Patient Database (RCIPD). Each MS patient was frequency matched to 4 controls according to age, sex and the year of MS registration to the RCIPD. Patients with a history of VTE and incomplete information of age and sex were excluded. All patients were followed up from the index year until VTE diagnosis, loss to follow-up or the end of 2010. We calculated the hazard ratios (HRs) and 95% confidence intervals (CIs) of VTE in the MS and comparison cohorts using Cox proportional hazards regression models.

RESULTS

We followed up 1238 MS patients and 4952 comparison patients for approximately 6437 and 27 595 person-years, respectively. After adjusting for age, sex and comorbidities, the MS patients exhibited a 6·87-fold increased risk of VTE compared with the control patients. Women with MS were associated with an 11·1-fold increased risk of VTE development compared with the non-MS women (95% CI: 2·70-45·5). The MS patients aged < 50 years exhibited a 14·8-fold increased risk of developing VTE compared with age-matched patients in the comparison cohort (95% CI: 2·99-73·4). The risk of VTE development increased with the duration of hospitalization stay.

CONCLUSION

MS patients are associated with significantly greater risk of developing VTE compared with non-MS patients.

Achieving Remission in Gulf War Illness: A Simulation-Based Approach to Treatment Design

Gulf War Illness (GWI) is a chronic multi-symptom disorder affecting up to one-third of the 700,000 returning veterans of the 1991 Persian Gulf War and for which there is no known cure. GWI symptoms span several of the body’s principal regulatory systems and include debilitating fatigue, severe musculoskeletal pain, cognitive and neurological problems. Using computational models, our group reported previously that GWI might be perpetuated at least in part by natural homeostatic regulation of the neuroendocrine-immune network. In this work, we attempt to harness these regulatory dynamics to identify treatment courses that might produce lasting remission. Towards this we apply a combinatorial optimization scheme to the Monte Carlo simulation of a discrete ternary logic model that represents combined hypothalamic-pituitary-adrenal (HPA), gonadal (HPG), and immune system regulation in males. In this work we found that no single intervention target allowed a robust return to normal homeostatic control. All combined interventions leading to a predicted remission involved an initial inhibition of Th1 inflammatory cytokines (Th1Cyt) followed by a subsequent inhibition of glucocorticoid receptor function (GR). These first two intervention events alone ended in stable and lasting return to the normal regulatory control in 40% of the simulated cases. Applying a second cycle of this combined treatment improved this predicted remission rate to 2 out of 3 simulated subjects (63%). These results suggest that in a complex illness such as GWI, a multi-tiered intervention strategy that formally accounts for regulatory dynamics may be required to reset neuroendocrine-immune homeostasis and support extended remission.

Varicella-zoster virus infections in patients treated with fingolimod: risk assessment and consensus recommendations for management

IMPORTANCE

Varicella-zoster virus (VZV) infections increasingly are reported in patients with multiple sclerosis (MS) and constitute an area of significant concern, especially with the advent of more disease-modifying treatments in MS that affect T-cell-mediated immunity.

OBJECTIVE

To assess the incidence, risk factors, and clinical characteristics of VZV infections in fingolimod-treated patients and provide recommendations for prevention and management.

DESIGN, SETTING, AND PARTICIPANTS

Rates of VZV infections in fingolimod clinical trials are based on pooled data from the completed controlled phases 2 and 3 studies (3916 participants) and ongoing uncontrolled extension phases (3553 participants). Male and female patients aged 18 through 55 years (18-60 years for the phase 2 studies) and diagnosed as having relapsing-remitting MS were eligible to participate in these studies. In the postmarketing setting, reporting rates since 2010 were evaluated.

INTERVENTIONS

In clinical trials, patients received fingolimod at a dosage of 0.5 or 1.25 mg/d, interferon beta-1a, or placebo. In the postmarketing setting, all patients received fingolimod, 0.5 mg/d (total exposure of 54,000 patient-years at the time of analysis).

MAIN OUTCOMES AND MEASURES

Calculation of the incidence rate of VZV infection per 1000 patient-years was based on the reporting of adverse events in the trials and the postmarketing setting.

RESULTS

Overall, in clinical trials, VZV rates of infection were low but higher with fingolimod compared with placebo (11 vs 6 per 1000 patient-years). A similar rate was confirmed in the ongoing extension studies. Rates reported in the postmarketing settings were comparable (7 per 1000 patient-years) and remained stable over time. Disproportionality in reporting herpes zoster infection was higher for patients receiving fingolimod compared with those receiving other disease-modifying treatments (empirical Bayes geometric mean, 2.57 [90% CI, 2.26-2.91]); the proportion of serious herpes zoster infections was not higher than the proportion for other treatments (empirical Bayes geometric mean, 1.88 [90% CI, 0.87-3.70]). Corticosteroid treatment for relapses might be a risk factor for VZV reactivation.

CONCLUSIONS AND RELEVANCE

Rates of VZV infections in clinical trials were low with fingolimod, 0.5 mg/d, but higher than in placebo recipients. Rates reported in the postmarketing setting are comparable. We found no sign of risk accumulation with longer exposure. Serious or complicated cases of herpes zoster were uncommon. We recommend establishing the patient's VZV immune status before initiating fingolimod therapy and immunization for patients susceptible to primary VZV infection. Routine antiviral prophylaxis is not needed, but using concomitant pulsed corticosteroid therapy beyond 3 to 5 days requires an individual risk-benefit assessment. Vigilance to identify early VZV symptoms is important to allow timely antiviral treatment.

An update on the use of natalizumab in the treatment of multiple sclerosis: appropriate patient selection and special considerations

In the context of an increasing repertoire of multiple sclerosis (MS) therapeutics, choosing the appropriate treatment for an individual patient is becoming increasingly challenging. Natalizumab, a humanized monoclonal antibody directed against alpha4beta1 integrin, has proven short-term and long-term efficacies in terms of relapse rate reduction, prevention of disability progression, and reduction of magnetic resonance imaging-detectable activity. It is well tolerated and has further been shown to improve patients' quality of life. Its use is limited by the risk of progressive multifocal leukoencephalopathy (PML), which occurs at an overall incidence of 3.78 cases per 1,000 patients. Three major risk factors for the occurrence of natalizumab-associated PML have been identified: John Cunningham virus (JCV) seropositivity, prior use of immunosuppressants, and treatment duration ≥2 years. Therefore, in patients considered for natalizumab therapy, as well as in patients receiving natalizumab, effective control of MS activity has to be balanced against the risk of an opportunistic central nervous system infection associated with a high risk of significant morbidity or death. Discontinuation of natalizumab is an issue in daily clinical practice, since it is an option to reduce the PML risk. However, after cessation of natalizumab therapy, currently, there is no approved strategy for avoiding postnatalizumab disease reactivation available. In this paper, short-term and long-term safety and efficacy data are reviewed. Issues in daily clinical practice, such as selection of patients, monitoring of patients, and natalizumab discontinuation, are discussed.

The efficacy and safety of daclizumab and its potential role in the treatment of multiple sclerosis

Daclizumab is a humanized monoclonal antibody of the immunoglobulin G1 (IgG1) isotype that binds to the α-subunit (CD25) of the high-affinity interleukin-2 (IL-2) receptor expressed on activated T cells and CD4+CD25+FoxP3+ regulatory T cells. Based on the assumption that it would block the activation and expansion of autoreactive T cells that are central to the immune pathogenesis of multiple sclerosis (MS), daclizumab was tested in several small open-label clinical trials in MS and demonstrated a profound inhibition of inflammatory disease activity. Surprisingly, accompanying mechanistic studies revealed that the most important biological effect of daclizumab was rather a dramatic expansion and activation of immunoregulatory CD56(bright) natural-killer (NK) cells that correlated with treatment response, while there was no or only minor effect on peripheral T-cell activation and function. These CD56(bright) NK cells were able to gain access to the central nervous system in MS and kill autologous activated T cells. Additional and relatively large phase IIb clinical trials showed that daclizumab, as add-on or monotherapy in relapsing-remitting (RR) MS, was highly effective in reducing relapse rate, disability progression, and the number and volume of gadolinium-enhancing, T1 and T2 lesions on brain magnetic resonance imaging (MRI), and reproduced the expansion of CD56(bright) NK cells as a biomarker for daclizumab activity. Daclizumab is generally very well tolerated and has shown a favorable adverse event (AE) profile in transplant recipients. However, several potentially serious and newly emerging AEs (mainly infections, skin reactions, elevated liver function tests and autoimmune phenomena in several body organs) may require strict safety monitoring programs in future clinical practice and place daclizumab together with other new and highly effective MS drugs as a second-line therapy. Ongoing phase III clinical trials in RRMS are expected to provide definite information on the efficacy and safety of daclizumab and to determine its place in the fast-growing armamentarium of MS therapies.

Optimized nonclinical safety assessment strategies supporting clinical development of therapeutic monoclonal antibodies targeting inflammatory diseases

An increasing number of immunomodulatory monoclonal antibodies (mAbs) and IgG Fc fusion proteins are either approved or in early-to-late stage clinical trials for the treatment of chronic inflammatory conditions, autoimmune diseases and organ transplant rejection. The exquisite specificity of mAbs, in combination with their multi-functional properties, high potency, long half-life (permitting intermittent dosing and prolonged pharamcological effects), and general lack of off-target toxicity makes them ideal therapeutics. Dosing with mAbs for these severe and debilitating but often non life-threatening diseases is usually prolonged, for several months or years, and not only affects adults, including sensitive populations such as woman of child-bearing potential (WoCBP) and the elderly, but also children. Immunosuppression is usually a therapeutic goal of these mAbs and when administered to patients whose treatment program often involves other immunosuppressive therapies, there is an inherent risk for frank immunosuppression and reduced host defence which when prolonged increases the risk of infection and cancer. In addition when mAbs interact with the immune system they can induce other adverse immune-mediated drug reactions such as infusion reactions, cytokine release syndrome, anaphylaxis, immune-complex-mediated pathology and autoimmunity. An overview of the nonclinical safety assessment and risk mitigation strategies utilized to characterize these immunomodulatory mAbs and Fc fusion proteins to support first-in human (FIH) studies and futher clinical development in inflammatory disease indications is provided. Specific emphasis is placed on the design of studies to qualify animal species for toxicology studies, early studies to investigate safety and define PK/PD relationships, FIH-enabling and chronic toxicology studies, immunotoxicity, developmental, reproductive and juvenile toxicity studies and studies to determine the potential for immunosuppression and reduced host defence against infection and cancer. Nonclinical strategies to facilitate clinical and market entry in the most efficient timeframe are presented.

Efficacy and side effects of natalizumab therapy in patients with multiple sclerosis

Natalizumab (Nat) is a humanized monoclonal antibody used for the treatment of relapsing multiple sclerosis (MS). Nat inhibits lymphocyte migration via the blood brain barrier (BBB) by blockage of an integrin adhesion molecule, very late antigen 4. During the phase III clinical trials, it was shown that Nat reduces disease activity and prevents disability progression. In addition, several smaller studies indicate a positive influence of Nat on cognition, depression, fatigue, and quality of life (Qol). Therapeutic efficacy has to be weighed against the risk of developing potentially fatal progressive multifocal leukoencephalopathy (PML), an opportunistic infection by JC-virus (JCV) with an incidence of 3.4/1000 (95% CI 3.08–3.74) in Nat treated MS patients. In this review article, we will review data on the presumed mechanism of Nat action, clinical and paraclinical efficacy parameters, and adverse drug reactions with a special focus on PML.

Effect of natalizumab on oxidative damage biomarkers in relapsing-remitting multiple sclerosis

BACKGROUND

Natalizumab is a monoclonal antibody used to treat multiple sclerosis. This study sought to determine whether the protective action of natalizumab involved a reduction in oxidative damage.

METHODS

Twenty-two multiple sclerosis patients fulfilling the revised McDonald criteria were assigned to treatment with 300 mg natalizumab intravenously once monthly (infusion every 4 weeks) in accordance with Spanish guidelines. Carbonylated proteins, 8-hydroxy-2'-deoxyguanosine, total glutathione, reduced glutathione, superoxide dismutase, glutathione peroxidase, and myeloperoxidase levels were measured at baseline and after 14 months' treatment, and the antioxidant gap was calculated.

RESULTS

Natalizumab prompted a drop in oxidative-damage biomarker levels, together with a reduction both in myeloperoxidase levels and in the myeloperoxidase/neutrophil granulocyte ratio. Interestingly, natalizumab induced nuclear translocation of Nrf2 and a fall in serum vascular cell adhesion molecule-1 levels.

CONCLUSION

These findings suggest that natalizumab has a beneficial effect on oxidative damage found in MS patients.

Treatment of chronic inflammatory demyelinating polyradiculoneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a sporadically occurring, acquired neuropathic condition of autoimmune origin with chronic progressive or relapsing-remitting disease course. CIDP is a treatable disorder; a variety of immunosuppressive and immunomodulatory agents are available to modify, impede, and even reverse the neurological deficits and sequelae that manifest in the course of the disease. However, in many cases CIDP is not curable. Challenges that remain in the treatment of CIDP patients are well recognized and include a remarkably individual heterogeneity in terms of disease course and treatment response as well as a lack of objective and feasible measures to predict and monitor the responsiveness to the available therapies. In this chapter an overview of the currently used drugs in the treatment of CIDP patients is given and some important and controversial issues that arise in the context of care for CIDP patients are discussed.

Established and novel disease-modifying treatments in multiple sclerosis

Multiple sclerosis (MS) is a presumed autoimmune disorder of the central nervous system, resulting in inflammatory demyelination and axonal and neuronal injury. New diagnostic criteria that incorporate magnetic resonance imaging have resulted in earlier and more accurate diagnosis of MS. Several immunomodulatory and immunosuppressive therapeutic agents are available for relapsing forms of MS, which allow individualized treatment based upon the benefits and risks. Disease-modifying therapies introduced in the 1990s, the beta-interferons and glatiramer acetate, have an established track record of efficacy and safety, although they require administration via injection. More recently, monoclonal antibodies have been engineered to act through specific mechanisms such as blocking alpha-4 integrin interactions (natalizumab) or lysing cells bearing specific markers, for example CD52 (alemtuzumab) or CD20 (ocrelizumab and ofatumumab). These agents can be highly efficacious, but sometimes have serious potential complications (natalizumab is associated with progressive multifocal leukoencephalopathy; alemtuzumab is associated with the development of new autoimmune disorders). Three new oral therapies (fingolimod, teriflunomide and dimethyl fumarate, approved for MS treatment from 2010 onwards) provide efficacy, tolerability and convenience; however, as yet, there are no long-term postmarketing efficacy and safety data in a general MS population. Because of this lack of long-term data, in some cases, therapy is currently initiated with the older, safer injectable medications, but patients are monitored closely with the plan to switch therapies if there is any indication of a suboptimal response or intolerance or lack of adherence to the initial therapy. For patients with MS who present with highly inflammatory and potentially aggressive disease, the benefit-to-risk ratio may support initiating therapy using a drug with greater potential efficacy despite greater risks (e.g. fingolimod or natalizumab if JC virus antibody-negative). The aim of this review is to discuss the clinical benefits, mechanisms of action, safety profiles and monitoring strategies of current MS disease-modifying therapies in clinical practice and of those expected to enter the market in the near future.

Purification of chimeric heavy chain monoclonal antibody EG2-hFc using hydrophobic interaction membrane chromatography: an alternative to protein-A affinity chromatography

Heavy chain monoclonal antibodies are being considered as alternative to whole-IgG monoclonal antibodies for certain niche applications. Protein-A chromatography which is widely used for purifying IgG monoclonal antibodies is also used for purifying heavy chain monoclonal antibodies as these molecules possess fully functional Fc regions. However, the acidic conditions used to elute bound antibody may sometimes also leach protein-A, which is immunotoxic. Low pH conditions also tend to make the mAb molecules unstable and prone to aggregation. Moreover, protein-A affinity chromatography does not remove aggregates already present in the feed. Hydrophobic interaction membrane chromatography (or HIMC) has already been studied as an alternative to protein-A chromatography for purifying whole-IgG monoclonal antibodies. This paper describes the use of HIMC for capturing a humanized chimeric heavy chain monoclonal antibody (EG2-hFC). Binding and eluting conditions were suitably optimized using pure EG2-hFC. Based on this, an HIMC method was developed for capture of EG2-hFC directly from cell culture supernatant. The EG2-hFc purity obtained in this single-step process was high. The glycan profiles of protein-A and HIMC purified monoclonal antibody samples were similar, clearly demonstrating that both techniques captured similarly glycosylated population of EG2-hFc. Moreover, this technique was able to resolve aggregates from monomeric form of the EG2-hFc.

Daclizumab-induced adverse events in multiple organ systems in multiple sclerosis

OBJECTIVE

To report 3 patients with multiple sclerosis (MS) who presented with daclizumab-related adverse events (AEs) in multiple organ systems.

METHODS

A retrospective chart review was performed of patients with MS who had clinical and histopathologic findings suggestive of daclizumab-induced AEs between 2004 and 2010 at the Johns Hopkins MS Clinic. This study met criteria for exemption from review from the institutional review board.

RESULTS

Of 20 total patients with MS who had been treated with daclizumab, 3 patients with clinical and histopathologic findings suggestive of daclizumab-induced AEs were identified. All patients were treated with Zenapax (1 mg/kg monthly IV infusions) outside of a clinical trial setting. Clinical manifestations after a mean treatment duration of 20 months consisted of diffuse rash and alopecia, diffuse lymphadenopathy, and breast nodules. Tissue histopathology demonstrated lymphocytic infiltrates with CD56-expressing cells in 2 patients (lymph node, breast nodule). On daclizumab discontinuation, the rash/alopecia and diffuse lymphadenopathy resolved, while the breast nodules stabilized.

CONCLUSIONS

Daclizumab-induced AEs can occur in various organ systems after a relatively prolonged duration of exposure and require clinician awareness. Future studies are needed to better understand the relationship between natural killer cells and daclizumab-related AEs.

The autoimmune disease-associated transcription factors EOMES and TBX21 are dysregulated in multiple sclerosis and define a molecular subtype of disease

We have identified a marked over-representation of transcription factors controlling differentiation of T, B, myeloid and NK cells among the 110 MS genes now known to be associated with multiple sclerosis (MS). To test if the expression of these genes might define molecular subtypes of MS, we interrogated their expression in blood in three independent cohorts of untreated MS (from Sydney and Adelaide) or clinically isolated syndrome (CIS, from San Francisco) patients. Expression of the transcription factors (TF) controlling T and NK cell differentiation, EOMES, TBX21 and other TFs was significantly lower in MS/CIS compared to healthy controls in all three cohorts. Expression was tightly correlated between these TFs, with other T/NK cell TFs, and to another downregulated gene, CCL5. Expression was stable over time, but did not predict disease phenotype. Optimal response to therapy might be indicated by normalization of expression of these genes in blood.

Ribosomal protein S6 mRNA is a biomarker upregulated in multiple sclerosis, downregulated by interferon treatment, and affected by season

Background:

Multiple Sclerosis (MS) is an immune-mediated disease of the central nervous system which responds to therapies targeting circulating immune cells.

Objective:

Our aim was to test if the T-cell activation gene expression pattern (TCAGE) we had previously described from whole blood was replicated in an independent cohort.

Methods:

We used RNA-seq to interrogate the whole blood transcriptomes of 72 individuals (40 healthy controls, 32 untreated MS). A cohort of 862 control individuals from the Brisbane Systems Genetics Study (BSGS) was used to assess heritability and seasonal expression. The effect of interferon beta (IFNB) therapy on expression was evaluated.

Results:

The MS/TCAGE association was replicated and rationalized to a single marker, ribosomal protein S6 (RPS6). Expression of RPS6 was higher in MS than controls ( p<0.0004), and lower in winter than summer ( p<4.6E-06). The seasonal pattern correlated with monthly UV light index ( R=0.82, p<0.002), and was also identified in the BSGS cohort ( p<0.0016). Variation in expression of RPS6 was not strongly heritable. RPS6 expression was reduced by IFNB therapy.

Conclusions:

These data support investigation of RPS6 as a potential therapeutic target and candidate biomarker for measuring clinical response to IFNB and other MS therapies, and of MS disease heterogeneity.

Update on immunopathogenesis and immunotherapy in multiple sclerosis

Multiple sclerosis is a chronic inflammatory demyelinating disease of the central nervous system. Both genetic and environmental factors are believed to contribute to the pathogenesis of the disease. Histopathological findings suggest that multiple sclerosis is an immune-mediated disease, involving both the cellular and humoral immune systems. Within the last 20 years, several disease-modifying therapies for the treatment of multiple sclerosis were established. Moreover, promising new substances are currently being tested in clinical trials and will likely broaden the therapeutic opportunities available within the upcoming years.

A review of the use of biological agents for chronic inflammatory demyelinating polyradiculoneuropathy

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a group of idiopathic, acquired, immune-mediated inflammatory demyelinating diseases of the peripheral nervous system. A majority of patients with CIDP respond to "first-line" treatment with IVIG, plasmapheresis and/or corticosteroids. There exists insufficient evidence to ascertain the benefit of treatment with "conventional" immunosuppressive drugs. The inconsistent efficacy, long-term financial burden and health risks of non-specific immune altering therapy have drawn recurrent attention to the possible usefulness of a variety of biological agents that target key aspects in the CIDP immunopathogenic pathways. This review aims to give an updated account of the scientific rationale and potential use of biological therapeutics in patients with CIDP. No specific treatment recommendations are given. The discovery, development and application of biological markers by modern molecular diagnostic techniques may help identify drug-naïve or treatment-resistant CIDP patients most likely to respond to targeted immunotherapy.

Chemotherapy and biotherapeutic agents for autoimmune diseases

New trends have emerged in treating patients with autoimmune diseases with medications traditionally used in oncology. This article will summarize a comprehensive literature review performed to identify effective chemotherapy and biotherapeutic agents for treating each of the main autoimmune subtypes (nervous, gastrointestinal, blood and blood vessel, skin, endocrine, and musculoskeletal systems). In addition to agents currently used, some of the newer therapeutic options show great promise to radically improve treatment choices when considering individualized plans. Improved outcomes and symptom management using newer nontraditional therapies provide a great impetus for oncology and nononcology healthcare professionals to remain abreast of the advancements made to current treatment options. All nurses (oncology and nononcology) need to be aware of these new trends and strengthen their understanding of certain oncology medications and their side effects, as well as establish the safe-handling practices necessary to administer these agents. The Oncology Nursing Society's Treatment Basics Course is one option that can provide nononcology nurses with the knowledge needed to fulfill new practice gaps. In addition, oncology nurses need to be aware of the many autoimmune diseases that may be treated with chemotherapy or biotherapy.

Daclizumab therapy for multiple sclerosis

Daclizumab is a humanized monoclonal antibody of IgG1 subtype that binds to the Tac epitope on the interleukin-2 (IL-2) receptor α-chain (CD25), thus, effectively blocking the formation of the high-affinity IL-2 receptor. Because the high-affinity IL-2 receptor signaling promotes expansion of activated T cells in vitro, daclizumab was designed as a therapy that selectively inhibits T-cell activation. Assuming the previous statement, daclizumab received regulatory approval as add-on therapy to standard immunosuppressive regimen for the prevention of acute allograft rejection in renal transplantation. Based on its putative mechanism of action (MOA), daclizumab represented an ideal therapy for T-cell-mediated autoimmune diseases and was subsequently tested in inflammatory uveitis and multiple sclerosis (MS). In both of these diseases, daclizumab therapy significantly inhibited target organ inflammation. Mechanistic studies in MS demonstrated that the MOA of daclizumab is surprisingly broad and that the drug exerts unexpected effects on multiple components of the innate immune system. Specifically, daclizumab dramatically expands and activates immunoregulatory CD56(bright) NK cells, which gain access to the intrathecal compartment in MS and can kill autologous activated T cells. Daclizumab also blocks trans-presentation of IL-2 by mature dendritic cells to primed T cells, resulting in profound inhibition of antigen-specific T cells. Finally, daclizumab modulates the development of innate lymphoid cells. In conclusion, daclizumab therapy, which is currently in phase III testing for inflammatory MS, has a unique MOA that does not limit migration of immune cells into the intrathecal compartment, but rather provides multifactorial immunomodulatory effects with resultant inhibition of MS-related inflammation.

Production and characterization of a CD25-specific scFv-Fc antibody secreted from Pichia pastoris

Antibodies against CD25 would be novel tools for the diagnosis and treatment of adult T cell leukemia lymphoma (ATLL) and many other immune disorders. In our previous work, we successfully produced the single-chain fragment of a variable antibody against CD25, the Dmab(scFv) antibody, using Pichia pastoris. Here, we describe a novel form of an antibody against CD25, the Dmab(scFv)-Fc antibody, also produced by P. pastoris. To construct the Dmab(scFv)-Fc antibody, the Dmab(scFv) antibody was genetically fused to the Fc fragment of a human IgG1 antibody. A fusion gene encoding Dmab(scFv)-Fc antibody was cloned into the pPIC9K plasmid and expressed at high levels, 60-70 mg/l, by P. pastoris under optimized conditions. The Dmab(scFv)-Fc antibody was similar to the Dmab(scFv) antibody in its binding specificity but different in its molecular form and Fc-mediated effector functions. The Dmab(scFv)-Fc antibody and the Dmab(scFv) antibody both bound to CD25-positive MJ cells but not to CD25-negative K562 cells. The Dmab(scFv)-Fc antibody existed as a dimer whereas the Dmab(scFv) antibody was a monomer because it lacks the Fc fragment. The Dmab(scFv)-Fc antibody enhanced the antibody-dependent cellular cytotoxicity of CD25-positive cancer cells, whereas the Dmab(scFv) antibody was inactive in the antibody-dependent cellular cytotoxicity assays. In addition, compared to the Dmab(scFv) antibody, the Dmab(scFv)-Fc antibody showed stronger immunosuppressive activity in the Con A-stimulated lymphocyte proliferation system and in the mixed lymphocyte reaction system. These results demonstrate that the Dmab(scFv)-Fc antibody produced in P. pastoris is functional, and therefore it might be developed as a novel diagnostic and therapeutic tool for ATLL and other immune disorders.

Multiple sclerosis: the role of cytokines in pathogenesis and in therapies

Multiple sclerosis, the clinical features and pathological correlate for which were first described by Charcot, is a chronic neuroinflammatory disease with unknown etiology and variable clinical evolution. Although neuroinflammation is a descriptive denominator in multiple sclerosis based on histopathological observations, namely the penetration of leukocytes into the central nervous system, the clinical symptoms of relapses, remissions and progressive paralysis are the result of losses of myelin and neurons. In the absence of etiological factors as targets for prevention and therapy, the definition of molecular mechanisms that form the basis of inflammation, demyelination and toxicity for neurons have led to a number of treatments that slow down disease progression in specific patient cohorts, but that do not cure the disease. Current therapies are directed to block the immune processes, both innate and adaptive, that are associated with multiple sclerosis. In this review, we analyze the role of cytokines in the multiple sclerosis pathogenesis and current/future use of them in treatments of multiple sclerosis.

From injection therapies to natalizumab: views on the treatment of multiple sclerosis

Discoveries of the mechanisms that underlie the pathogenesis of multiple sclerosis have been acquired at an impressive rate over the last few decades and, as a consequence, a growing number of treatments are becoming available for this disease. This review first analyzes the experience from the early stages of the disease-modifying therapies, then, expanding on the concept of early treatment for improved outcomes, it focuses on natalizumab and its major complication, progressive multifocal leukoencephalopathy. We offer views on the risks associated with the use of natalizumab by underscoring the importance of the JC virus serology and by providing preliminary data on our experience with the extended interval dosing of natalizumab. This approach, which advocates individualized treatment plans, raises the question of the minimum effective natalizumab dose. Extended interval dosing suggests efficacy can be maintained while providing advantages of costs and convenience over regular monthly dosing. More data examining this strategy are necessary.

Multiple sclerosis: pathogenesis and treatment

Multiple sclerosis (MS) is a chronic inflammatory autoimmune demyelinating disease of the central nervous system. It affects approximately 400,000 people in the United States and onset is usually during young adulthood. There are four clinical forms of MS, of which relapsing remitting type is the most common. As the etiology of MS is unknown, finding a cure will remain challenging. The main mechanism of injury appears to be inflammation and 8 agents are now FDA approved to help control MS. These agents for relapsing forms of MS target different parts of the immune system, with the end goal of decreasing and avoiding further inflammation. No agents are FDA approved for the primary progressive version of MS. FDA approved agents include four preparations of interferon β (Avonex, Rebif, Betaseron and Extavia), glatiramer acetate (Copaxone), mitoxantrone (Novantrone), natalizumab (Tysabri) and fingolimod (Gilenya). There are several drug undergoing phase II and III trials. The heterogeneity of the MS disease process, individual patient response, and medication toxicities continue to challenge the treating physician.

Peripheral accumulation of newly produced T and B lymphocytes in natalizumab-treated multiple sclerosis patients

The anti-α4 monoclonal antibody natalizumab inhibits lymphocyte extravasation into the central nervous system and increases peripheral T and B lymphocytes in multiple sclerosis patients. To investigate whether the lymphocyte accumulation was due to a higher lymphocyte production, an altered homeostasis, or a differential transmigration of lymphocyte subsets through endothelia, T-cell receptor excision circles and kappa-deleting recombination excision circles were quantified before and after treatment, T-cell receptor repertoire was analyzed by spectratyping, and T- and B-lymphocyte subset migration was studied using transwell coated with vascular and lymphatic endothelial cells. We found that the number of newly produced T and B lymphocytes is increased because of a high release and of a low propensity of naïve subsets to migrate across endothelial cells. In some patients this resulted in an enlargement of T-cell heterogeneity. Because new lymphocyte production ensures the integrity of immune surveillance, its quantification could be used to monitor natalizumab therapy safety.

Effects of an aqueous extract of North American ginseng on MOG(35-55)-induced EAE in mice

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system, in which the release of reactive oxygen species by infiltrating immune cells contributes to demyelination. American ginseng ( Panax quinquefolius ) is a natural health product with numerous beneficial properties, including anti-inflammatory and anti-oxidant effects. The purpose of this study was to determine whether ginseng could influence the course of the disease experimental autoimmune encephalomyelitis (EAE), an animal model of MS. C57BL/6J mice were immunized with MOG((35-55)) peptide to induce EAE. After clinical disease appeared, mice received either oral doses of an aqueous extract of ginseng (150 mg/kg body mass), or the vehicle. Clinical symptoms were recorded, and spinal cord tissue samples were analyzed for pathological signs of disease. The aqueous extract of ginseng significantly decreased (i) clinical signs of EAE, (ii) levels of circulating TNF-α, and (iii) central nervous system immunoreactive iNOS and demyelination scores, without a change in other neuropathological measures. This study shows that an aqueous extract of ginseng may be able to attenuate certain signs of EAE, suggesting that it may be a useful adjuvant therapy for MS.