CD40-Mediated NF-κB Activation in B Cells Is Increased in Multiple Sclerosis and Modulated by Therapeutics.

CD40 interacts with CD40L and plays an essential role in immune regulation and homeostasis. Recent research findings, however, support a pathogenic role of CD40 in a number of autoimmune diseases. We previously showed that memory B cells from relapsing-remitting multiple sclerosis (RRMS) patients exhibited enhanced proliferation with CD40 stimulation compared with healthy donors. In this study, we used a multiparameter phosflow approach to analyze the phosphorylation status of NF-κB and three major MAPKs (P38, ERK, and JNK), the essential components of signaling pathways downstream of CD40 engagement in B cells from MS patients. We found that memory and naive B cells from RRMS and secondary progressive MS patients exhibited a significantly elevated level of phosphorylated NF-κB (p-P65) following CD40 stimulation compared with healthy donor controls. Combination therapy with IFN-ß-1a (Avonex) and mycophenolate mofetil (Cellcept) modulated the hyperphosphorylation of P65 in B cells of RRMS patients at levels similar to healthy donor controls. Lower disease activity after the combination therapy correlated with the reduced phosphorylation of P65 following CD40 stimulation in treated patients. Additionally, glatiramer acetate treatment also significantly reduced CD40-mediated P65 phosphorylation in RRMS patients, suggesting that reducing CD40-mediated p-P65 induction may be a general mechanism by which some current therapies modulate MS disease.

Correlating Function and Imaging Measures of the Medial Longitudinal Fasciculus.

OBJECTIVE: To test the validity of diffusion tensor imaging (DTI) measures of tissue injury by examining such measures in a white matter structure with well-defined function, the medial longitudinal fasciculus (MLF). Injury to the MLF underlies internuclear ophthalmoparesis (INO). METHODS: 40 MS patients with chronic INO and 15 healthy controls were examined under an IRB-approved protocol. Tissue integrity of the MLF was characterized by DTI parameters: longitudinal diffusivity (LD), transverse diffusivity (TD), mean diffusivity (MD) and fractional anisotropy (FA). Severity of INO was quantified by infrared oculography to measure versional disconjugacy index (VDI). RESULTS: LD was significantly lower in patients than in controls in the medulla-pons region of the MLF (p < 0.03). FA was also lower in patients in the same region (p < 0.0004). LD of the medulla-pons region correlated with VDI (R = -0.28, p < 0.05) as did FA in the midbrain section (R = 0.31, p < 0.02). CONCLUSIONS: This study demonstrates that DTI measures of brain tissue injury can detect injury to a functionally relevant white matter pathway, and that such measures correlate with clinically accepted evaluation indices for INO. The results validate DTI as a useful imaging measure of tissue integrity.

Asynchrony in executive networks predicts cognitive slowing in multiple sclerosis.

OBJECTIVE: Cognitive slowing is a core neuropsychological symptom of Multiple Sclerosis (MS). We aimed to assess the extent to which cognitive slowing in MS was predicted by changes in dorsolateral prefrontal networks. METHOD: We assessed patients with relapsing-remitting MS and healthy controls (HCs) on measures of processing speed. Participants underwent a functional MRI while performing a processing speed task to allow assessment of task-based connectivity. RESULTS: Patients were slower than HCs on the processing speed tasks. Patients showed attenuated connectivity between right and left dorsolateral prefrontal cortex (DLPFC) and task-relevant brain regions compared to HCs during processing speed task performance. Patients' connectivity with DLPFC in these group-disparate networks accounted for significant variability in their performance on processing speed measures administered both in and out of the imaging environment. Specifically, patients who had stronger functional connections with DLPFC in group-disparate networks performed faster than patients with weaker connections with DLPFC in group-disparate networks. CONCLUSION: Results suggest that MS-related cognitive slowing can be accounted for by systemic alterations in executive functional networks.

Multiple sclerosis-related white matter microstructural change alters the BOLD hemodynamic response.

Multiple sclerosis (MS) results in inflammatory damage to white matter microstructure. Prior research using blood-oxygen-level dependent (BOLD) imaging indicates MS-related alterations to brain function. What is currently unknown is the extent to which white matter microstructural damage influences BOLD signal in MS. Here we assessed changes in parameters of the BOLD hemodynamic response function (HRF) in patients with relapsing-remitting MS compared to healthy controls. We also used diffusion tensor imaging to assess whether MS-related changes to the BOLD-HRF were affected by changes in white matter microstructural integrity. Our results showed MS-related reductions in BOLD-HRF peak amplitude. These MS-related amplitude decreases were influenced by individual differences in white matter microstructural integrity. Other MS-related factors including altered reaction time, limited spatial extent of BOLD activity, elevated lesion burden, or lesion proximity to regions of interest were not mediators of group differences in BOLD-HRF amplitude. Results are discussed in terms of functional hyperemic mechanisms and implications for analysis of BOLD signal differences.

The effect of glatiramer acetate therapy on functional properties of B cells from patients with relapsing-remitting multiple sclerosis.

IMPORTANCE: This study describes what is, to our knowledge, the previously unknown effect of glatiramer acetate therapy on B cells in patients with relapsing-remitting multiple sclerosis (MS). OBJECTIVE: To determine whether glatiramer acetate therapy normalizes dysregulated B-cell proliferation and cytokine production in patients with MS. DESIGN, SETTING, AND PARTICIPANTS: Twenty-two patients with MS who were receiving glatiramer acetate therapy and 22 treatment-naive patients with MS were recruited at The University of Texas Southwestern Medical Center MS clinic. Cell samples from healthy donors were obtained from HemaCare (Van Nuys, California) or Carter Blood Bank (Dallas, Texas). Treatment-naive patients with MS had not received any disease-modifying therapies for at least 3 months before the study. EXPOSURES: Glatiramer acetate therapy for at least 3 months at the time of the study. MAIN OUTCOMES AND MEASURES: B-cell phenotype and proliferation and immunoglobulin and cytokine secretion. RESULTS: A restoration of interleukin 10 production by peripheral B cells was observed in patients undergoing glatiramer acetate therapy as well as a significant reduction of interleukin 6 production in a subset of patients who received therapy for less than 32 months. Furthermore, proliferation in response to high-dose CD40L was altered and immunoglobulin production was elevated in in vitro-activated B cells obtained from patients who received glatiramer acetate. CONCLUSIONS AND RELEVANCE: Glatiramer acetate therapy remodels the composition of the B-cell compartment and influences cytokine secretion and immunoglobulin production. These data suggest that glatiramer acetate therapy affects several aspects of dysregulated B-cell function in MS that may contribute to the therapeutic mechanisms of glatiramer acetate.

Reduced spontaneous sympathetic nerve activity in multiple sclerosis patients.

For the first time, we obtained direct intra-neural measurements of muscle sympathetic nerve activity (MSNA) in relapsing-remitting multiple sclerosis (MS) patients to test the hypothesis that spontaneous resting MSNA is reduced in MS patients compared to age, sex-matched healthy controls. Spontaneous MSNA (microneurography; peroneal nerve), plasma norepinephrine, arterial blood pressure (finger photoplethysmography), and heart rate were measured at rest in three groups: 1) relapsing-remitting MS patients on disease modifying therapy only (MS-DT; n=6); 2) relapsing-remitting MS patients on disease modifying therapy and medications for MS-related symptoms that are known to effect the central nervous system (MS-DT/ST; n=5), and 3) healthy age and sex-matched controls (CON; n=6). Compared to the CON group, MSNA burst frequency (bursts/min) was significantly lower in both MS-DT (P=0.027) and MS-DT/ST groups (P=0.003). Similarly, MSNA burst incidence (bursts/100 heartbeats) was significantly reduced in both MS-DT (P=0.049) and MS-DT/ST groups (P=0.004) compared to the CON group. Burst frequency and burst incidence were not different between MS-DT and MS-DT/ST groups. Resting plasma norepinephrine was also significantly lower in both MS-DT (P=0.039) and MS-DT/ST groups (P=0.021) compared to the CON group. Reduced MSNA may signify an important dysfunction in autonomic control of cardiovascular function in patients with MS.

Nurses' perspective on approaches to limit flu-like symptoms during interferon therapy for multiple sclerosis.

BACKGROUND: Several interferon beta (IFNß) formulations are approved for first-line use as disease-modifying therapies to treat patients with multiple sclerosis (MS). Systemic post-injection reactions, often termed flu-like symptoms (FLS), occur in approximately half of all patients treated with IFNßs and can affect adherence to therapy. These symptoms, which include pyrexia, chills, malaise, myalgia, and headaches, usually resolve within 24 hours or persist intermittently following each injection. Because FLS, which usually occur early in the treatment course and diminish over time, are a primary cause of nonadherence to IFNß therapy, it is important to employ strategies that can attenuate these side effects. METHODS: To identify interventions effective in limiting FLS, a panel of United States-based nurses with expertise in MS patient care was convened and a literature review completed. RESULTS: Panel consensus was reached on specific interventions that can attenuate FLS. These prevention and mitigation strategies include dose titration, analgesia, and optimal injection timing, as well as other techniques that panel members have found useful in their clinical practice experience. CONCLUSIONS: These measures, in addition to effective patient education, will help to reduce the incidence of FLS secondary to IFNß therapy, improve patient medication adherence, and positively affect long-term clinical outcomes.

JC virus in CD34+ and CD19+ cells in patients with multiple sclerosis treated with natalizumab.

IMPORTANCE: Infection with JC virus (JCV) may lead to development of demyelinating progressive multifocal leukoencephalopathy in patients with multiple sclerosis (MS) who are treated with natalizumab. OBJECTIVE: To determine whether mononuclear cells in circulation from MS patients treated with natalizumab harbor JCV DNA. DESIGN, SETTING, AND PARTICIPANTS: In this prospective investigation, we enrolled 49 MS patients from the Clinical Center for Multiple Sclerosis at The University of Texas Southwestern Medical Center and 18 healthy volunteers. We drew 120-mL blood samples from 26 MS patients at baseline and at approximately 3-month intervals to 10 months during the course of natalizumab infusions. One blood sample was drawn from 23 MS patients receiving natalizumab for more than 24 months and from 18 healthy volunteers. INTERVENTIONS: Natalizumab treatment of MS. MAIN OUTCOMES AND MEASURES: The blood samples were separated using flow cytometry into CD34+, CD19+, and CD3+ cell subsets; DNA templates were prepared using quantitative polymerase chain reaction for JCV DNA identification. Plasma samples were tested for anti-JCV antibodies by enzyme-linked immunosorbent assays performed at the Laboratory of Molecular Medicine and Neuroscience, National Institute of Neurological and Communicative Diseases and Stroke. RESULTS: Thirteen of the 26 patients (50%) with baseline and follow-up blood samples had detectable viral DNA in at least 1 cell compartment at 1 or more points. Ten of the 23 patients (44%) receiving treatment for more than 24 months and 3 of the 18 healthy volunteers (17%) also had detectable viral DNA in 1 or more cell compartment. Fifteen of the 49 MS patients (31%) were confirmed to harbor JCV in CD34+ cells and 12 of 49 (24%) in CD19+ cells. Only 1 of 18 healthy volunteers were viremic in CD34+ cells and none in CD19+ cells. Nine patients and 1 healthy volunteer were viremic but had seronegative test results for JCV antibodies. CONCLUSIONS AND RELEVANCE: JC virus DNA was detectable within cell compartments of natalizumab-treated MS patients after treatment inception and longer. JC virus DNA may harbor in CD34+ cells in bone marrow that mobilize into the peripheral circulation at high concentrations. Latently infected cells initiate differentiation to CD19+ cells that favors growth of JCV. These data link the mechanism of natalizumab treatment with progressive multifocal leukoencephalopathy.

Uhthoff's phenomena in MS--clinical features and pathophysiology.

In the late 19(th) century, Wilhelm Uhthoff reported on a series of patients with acute optic neuritis who manifested similar recurrent, stereotyped visual symptoms that were of paroxysmal onset, short in duration, and reversible. These 'Uhthoff's phenomena', which are a feature of multiple sclerosis (MS) and other demyelinating diseases, can be triggered by factors including the perimenstrual period, exercise, infection, fever, exposure to high ambient temperatures, and psychological stress. Here, we characterize the clinical, pathophysiological and neurotherapeutic challenges associated with Uhthoff's phenomena, and discuss the differentiation of these events from other paroxysmal, acute or subacute changes in functional capabilities and neurological symptoms in MS. For instance, whereas MS exacerbations are contingent on immune dysregulation, Uhthoff's phenomena are predicated on ion channel modifications, in conjunction with thermoregulatory derangements that transiently alter the conduction properties of demyelinated axons. An understanding of these pathophysiological underpinnings of Uhthoff's phenomena is germane to their recognition and timely treatment.

Effect of 4-aminopyridine on vision in multiple sclerosis patients with optic neuropathy.

OBJECTIVE: The objective of this randomized, double-blind, placebo-controlled, crossover study was to examine if patients with optic neuropathy would derive a therapeutic benefit from 4-aminopyridine (4-AP) treatment. Furthermore, the study was intended to determine if patients with certain P100 latencies or retinal nerve fiber layer (RNFL) measures would be more likely to respond to therapy. METHODS: Patients were enrolled in a randomized, placebo-controlled, double-blind, crossover study of 10 weeks duration. Patients underwent visual evoked potentials (VEP), optical coherence tomography (OCT), and visual acuity before starting 5 weeks of either placebo or 4-AP. After 5 weeks, they completed a second evaluation (VEP, OCT, and visual acuity) and were crossed over between treatment arms. Five weeks later, they had their final evaluation. All investigators were blinded to treatment arm until after data analysis. RESULTS: On average, patients had faster P100s on 4-AP when compared to placebo. A subset of patients had distinct responses to 4-AP as measured by improvements in visual acuity. Finally, eyes with an RNFL measure between 60 and 80 µm had the highest response rate. CONCLUSIONS: 4-Aminopyridine is useful for improving vision in patients with demyelinating optic neuropathy. Future clinical trials may be able to enrich a patient population for potential responders using OCT and VEP measures. Selecting patients for future trials should use RNFL measures as part of inclusion/exclusion criteria. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence supporting the use of 4-AP in certain patients with optic neuropathy to improve visual function (patients with RNFL between 60 and 80 µm).

Facilitating medication adherence in patients with multiple sclerosis.

This article reviews adherence to medication in multiple sclerosis (MS) patients from the perspective of nurse and social worker authors. It reviews data on patient adherence and offers practical, evidence-based strategies that health-care providers can use to facilitate adherence. In addition, it examines how emerging MS therapies may affect patient adherence and associated interventions. To promote adherence, interventions need to incorporate new and creative approaches. A proactive approach includes assessing patient needs and lifestyle before the start of medication and selecting the most appropriate disease-modifying therapy for each individual patient. Including multidisciplinary expertise and services in the treatment plan can be part of a comprehensive, holistic approach to helping patients and families. Optimization of health-care provider roles is likely to facilitate improved adherence.

Changes in JC virus-specific T cell responses during natalizumab treatment and in natalizumab-associated progressive multifocal leukoencephalopathy.

Progressive multifocal leukoencephalopathy (PML) induced by JC virus (JCV) is a risk for natalizumab-treated multiple sclerosis (MS) patients. Here we characterize the JCV-specific T cell responses in healthy donors and natalizumab-treated MS patients to reveal functional differences that may account for the development of natalizumab-associated PML. CD4 and CD8 T cell responses specific for all JCV proteins were readily identified in MS patients and healthy volunteers. The magnitude and quality of responses to JCV and cytomegalovirus (CMV) did not change from baseline through several months of natalizumab therapy. However, the frequency of T cells producing IL-10 upon mitogenic stimulation transiently increased after the first dose. In addition, MS patients with natalizumab-associated PML were distinguished from all other subjects in that they either had no detectable JCV-specific T cell response or had JCV-specific CD4 T cell responses uniquely dominated by IL-10 production. Additionally, IL-10 levels were higher in the CSF of individuals with recently diagnosed PML. Thus, natalizumab-treated MS patients with PML have absent or aberrant JCV-specific T cell responses compared with non-PML patients, and changes in T cell-mediated control of JCV replication may be a risk factor for developing PML. Our data suggest further approaches to improved monitoring, treatment and prevention of PML in natalizumab-treated patients.

Rituximab dosing and monitoring strategies in neuromyelitis optica patients: creating strategies for therapeutic success.

BACKGROUND: Neuromyelitis optica (NMO) is an autoimmune condition that predominantly causes severe optic neuritis and transverse myelitis. Rituximab therapy has dramatically improved patient care, but standardized dosing regimens and guidelines are lacking. OBJECTIVES: The objective of this study was to define a rituximab dosing strategy for NMO patients that achieves the lowest rate of relapses. METHODS: This was a retrospective chart review of patients treated with various doses of rituximab. RESULTS: Combining data from the NMO and multiple sclerosis (MS) patients, identified that the mean number of days after a 100 mg dose of rituximab until the CD19 population was greater than 2% was 99 days (standard deviation 36, range 43-172). When allowed to rise, the mean number of days after a 1000 mg dose of rituximab until the CD19 population was greater than 2% was 184 (standard deviation 72, range 52-288). The median number of days until a CD19 percentage of 2% was achieved was 133 days in the 100 mg dosing arm and 259 days in the 1000 mg dosing arm. Analysis of the survival curves via both the Mantel-Cox log-rank test and the Wilcoxon test determined that the difference between medial survival for 100 and 1000 mg doses was statistically significant with p-values <0.0001. CONCLUSIONS: Low doses of rituximab have a high rate of early B-cell repopulation. Any NMO patient treated with rituximab should be followed with monthly CD19 counts in order to identify the rare, but clinically significant, early repopulators.

Diffusion tensor imaging the medial longitudinal fasciculus in INO: opportunities and challenges.

The medial longitudinal fasciculus (MLF) is a white matter pathway in the brainstem that plays a key role in coordinating eye movements. Injury to the MLF leads to abnormalities in eye movements that can be measured with high precision by oculography, making it an ideal eloquent pathway to study imaging/function correlates. Tractography is an emerging method for identifying white matter pathways and offers the tantalizing promise of noninvasive, quantitative characterization of tissue integrity underlying functional deficits. However, the small caliber of the MLF and partial volume averaging with signal from nearby cerebrospinal fluid pose severe technical challenges to tractography-based delineation of the MLF. We discuss progress toward the goal of imaging the MLF and potential benefits of achieving this goal. Initial work suggests that ultra-high field (7 tesla) may complement tractography for characterizing the MLF.

Symptomatic therapy in multiple sclerosis.

Multiple sclerosis is the most common disabling neurological disease of young adults. The ability to impact the quality of life of patients with multiple sclerosis should not only incorporate therapies that are disease modifying, but should also include a course of action for the global multidisciplinary management focused on quality of life and functional capabilities.

A one-year prospective, randomized, placebo-controlled, quadruple-blinded, phase II safety pilot trial of combination therapy with interferon beta-1a and mycophenolate mofetil in early relapsing-remitting multiple sclerosis (TIME MS).

BACKGROUND: Mycophenolate mofetil (MMF) is an oral DNA base synthesis inhibitor with immunomodulatory effects on B cells, T cells, and macrophages. OBJECTIVE: To conduct a safety and tolerability pilot study of interferon beta-1a (IFN-b1a) in combination with either placebo or oral MMF in multiple sclerosis (MS). METHODS: Twenty-four treatment-naïve R-RMS patients participated in a one-year prospective, placebo-controlled, blinded, safety pilot clinical trial. Every patient injected weekly intramuscular interferon beta-1a. The cohort was then randomized (1 : 1) to either active oral MMF or identical-appearing placebo tablets. Clinical evaluations were assessed every 3 months, along with brain MRI scans performed at baseline and repeated every 60 days for one year. Comprehensive laboratory assessments were monitored for safety, along with adverse events. RESULTS: In this small pilot investigation, no differences were identified between the two treatment groups with respect to patient-reported adverse events, MRI metrics, or laboratory abnormalities. Notwithstanding these observations, and the limited number of patients treated, trends appeared to favor the combination therapy regimen. CONCLUSIONS: The combination treatment regimen of interferon beta-1a and MMF appeared to be well tolerated in this pilot study. Despite the small sample size, therapeutic trends were observed in favor of combination therapy. An adequately powered controlled trial of MMF in MS appears warranted.

A randomized, blinded, parallel-group, pilot trial of mycophenolate mofetil (CellCept) compared with interferon beta-1a (Avonex) in patients with relapsing-remitting multiple sclerosis.

BACKGROUND: Mycophenolate mofetil (MMF, CellCept®) has been utilized as an antirejection agent in transplant recipients and in patients with myriad autoimmune disorders including multiple sclerosis (MS). OBJECTIVE: To investigate radiographic and clinical safety involving monotherapy use of daily oral MMF (1 g b.i.d.) versus weekly intramuscular interferon beta 1a (Avonex® at 30 mcg) in relapsing-remitting MS (RRMS). METHODS: We organized a randomized, serial, 6-monthly, MRI-blinded, parallel-group multicenter pilot study to determine the safety of MMF versus interferon beta monotherapy in 35 untreated patients with RRMS, all of whom exhibited evidence of gadolinium (Gd) enhancement on a screening MRI of the brain. The primary outcome was the reduction in the cumulative mean number of combined active lesions (CAL), new Gd-enhancing lesions, and new T2 lesions on MRI analyses. RESULTS: Both interferon beta and MMF appeared safe and well tolerated in the majority of patients. There was no difference between MMF therapy and the standard regimen of interferon beta therapy on the primary safety MRI endpoints of the study. However, the MMF group showed a trend toward a lower accumulation of combined active lesions, CAL, Gd and T2 lesions when compared with interferon beta treated patients. CONCLUSIONS: The results from this pilot study suggest that the application of MMF monotherapy in MS deserves further exploration.

Memory B cells from a subset of treatment-naïve relapsing-remitting multiple sclerosis patients elicit CD4(+) T-cell proliferation and IFN-γ production in response to myelin basic protein and myelin oligodendrocyte glycoprotein.

Recent evidence suggests that B- and T-cell interactions may be paramount in relapsing-remitting MS (RRMS) disease pathogenesis. We hypothesized that memory B-cell pools from RRMS patients may specifically harbor a subset of potent neuro-APC that support neuro-Ag reactive T-cell proliferation and cytokine secretion. To test this hypothesis, we compared CD80 and HLA-DR expression, IL-10 and lymphotoxin-α secretion, neuro-Ag binding capacity, and neuro-Ag presentation by memory B cells from RRMS patients to naïve B cells from RRMS patients and to memory and naïve B cells from healthy donors (HD). We identified memory B cells from some RRMS patients that elicited CD4(+) T-cell proliferation and IFN-γ secretion in response to myelin basic protein and myelin oligodendrocyte glycoprotein. Notwithstanding the fact that the phenotypic parameters that promote efficient Ag presentation were observed to be similar between RRMS and HD memory B cells, a corresponding capability to elicit CD4(+) T-cell proliferation in response to myelin basic protein and myelin oligodendrocyte glycoprotein was not observed in HD memory B cells. Our results demonstrate for the first time that the memory B-cell pool in RRMS harbors neuro-Ag specific B cells that can activate T cells.

Longitudinal study of vision and retinal nerve fiber layer thickness in multiple sclerosis.

OBJECTIVE: Cross-sectional studies of optical coherence tomography (OCT) show that retinal nerve fiber layer (RNFL) thickness is reduced in multiple sclerosis (MS) and correlates with visual function. We determined how longitudinal changes in RNFL thickness relate to visual loss. We also examined patterns of RNFL thinning over time in MS eyes with and without a prior history of acute optic neuritis (ON). METHODS: Patients underwent OCT measurement of RNFL thickness at baseline and at 6-month intervals during a mean follow-up of 18 months at 3 centers. Low-contrast letter acuity (2.5%, 1.25% contrast) and visual acuity (VA) were assessed. RESULTS: Among 299 patients (593 eyes) with >or=6 months follow-up, eyes with visual loss showed greater RNFL thinning compared to eyes with stable vision (low-contrast acuity, 2.5%: p < 0.001; VA: p = 0.005). RNFL thinning increased over time, with average losses of 2.9microm at 2 to 3 years and 6.1microm at 3 to 4.5 years (p < 0.001 vs 0.5-1-year follow-up interval). These patterns were observed for eyes with or without prior history of ON. Proportions of eyes with RNFL loss greater than test-retest variability (>or=6.6microm) increased from 11% at 0 to 1 year to 44% at 3 to 4.5 years (p < 0.001). INTERPRETATION: Progressive RNFL thinning occurs as a function of time in some patients with MS, even in the absence of ON, and is associated with clinically significant visual loss. These findings are consistent with subclinical axonal loss in the anterior visual pathway in MS, and support the use of OCT and low-contrast acuity as methods to evaluate the effectiveness of putative neuroprotection protocols.