MS Abstracts 02c-2g7

Histamine (HA), a biogenic amine with a broad spectrum of activities in both physiological and pathological settings, plays a key regulatory role in Experimental Allergic Encephalomyelitis, the autoimmune model of Multiple Sclerosis.

HA exerts its effect through four G protein-coupled Receptors designated HA Receptor H1, H2, H3, and H4.

We report here that, compared with wild-type animals, mice with a disrupted HA H3 Receptor (H3RKO), the expression of which is normally confined to cells of the Nervous System, develop more severe disease and NeuroInflammation.

We show that this effect is associated with dysregulation of Blood-Brain Barrier permeability and increased expression of MIP-2, IP-10, and CXCR3 by peripheral T-Cells.

Our data suggest that pharmacological targeting of the H3R may be useful in preventing the development and formation of new lesions in Multiple Sclerosis, thereby significantly limiting the progression of the disease.

Cell transplant therapies are currently under active consideration for a number of Degenerative Diseases.

In the Immune-Mediated Demyelinating-NeuroDegenerative Disease Multiple Sclerosis (MS), only the Myelin Sheaths of the CNS are lost, while Schwann Cell Myelin of the PNS remains normal.

This, and the finding that Schwann Cells can Myelinate CNS Axons, has focussed interest on Schwann Cell transplants to repair Myelin in MS.

However, the experimental use of these cells for Myelin repair in animal models has revealed a number of problems relating to the incompatibility between Peripheral Glial Cells and the CNS Glial environment.

Here, we have tested whether these difficulties can be avoided by using an earlier stage of the Schwann Cell lineage, the Schwann Cell Precursor (SCP).

For direct comparison of these two cell types, we implanted Schwann Cells from post-natal rat Nerves and SCPs from embryo day 14 (E14) rat Nerves into the CNS under various experimental conditions.

Examination 1 and 2 months later showed that in the presence of naked CNS Axons, both types of cell form Myelin that antigenically and ultrastructurally resembles that formed by Schwann Cells in Peripheral Nerves.

In terms of every other parameter we studied, however, the cells in these two implants behaved remarkably differently.

As expected from previous work, Schwann Cell implants survive poorly unless the cells find Axons to Myelinate.

The cells do not migrate significantly from the implantation site, fail to integrate with host Oligodendrocytes and Astrocytes, and form little Myelin when challenged with Astrocyte-rich environment in the Retina.

Following SCP implantation, on the other hand, the cells survive well, migrate through normal CNS tissue, interface smoothly and intimately with host Glial Cells and Myelinate extensively among the Astrocytes of the Retina.

Furthermore, when implanted at a distance from a DeMyelinated lesion, SCPs but not Schwann Cells migrate through normal CNS tissue to reach the lesion and generate new Myelin.

These features of SCP implants are all likely to be helpful attributes for a Myelin repair cell. Since these cells also form Schwann Cell Myelin that is arguably likely to be resistant to MS pathology.

They share some of the main advantages of Schwann Cells without suffering from the disadvantages that render Schwann Cells less than ideal candidates for transplantation into MS lesions.

Objective
To investigate the influence of cigarette smoking on progression and disability accumulation in Multiple Sclerosis (MS).

Methods
Information on past and present smoking of 364 patients with MS was obtained through a structured questionnaire survey.

We used Kaplan-Meier analyses and Cox regression models to evaluate:
1. The influence of smoking on the development and age at onset of secondary progression
2. On the age at onset of progression in patients with Primary/Progressive MS
3. On the time from disease onset to Expanded Disability Status Scale (EDSS) scores 4.0 and 6.0 in all patients

We also investigated the correlation between smoked pack-years and EDSS scores and the rate of progression as measured with the Multiple Sclerosis Severity Score.

Results
We found no significant associations between cigarette smoking and any of the used measures.

Conclusion
Our data suggest that cigarette smoking has no influence on disease progression or accumulation of disability in Multiple Sclerosis.

Magnetic Resonance Imaging (MRI) has emerged as a powerful noninvasive tool to assist in the diagnosis and monitoring of Multiple Sclerosis (MS).

In addition, investigators have used MRI metrics as supportive outcome measures to explore drug efficacy in clinical trials.

Conventional MRI surrogates provide information at the macroscopic level but lack sensitivity and specificity in identifying the full extent of underlying MS pathology.

They also show relatively weak relationships to clinical status such as predictive strength for clinical change.

Advanced MRI techniques involving quantitative measures of diffuse damage in Normal-Appearing (NA) White Matter (WM) and Gray Matter (GM) may help in resolving this apparent clinical MRI paradox.

T₂ HypoIntensity has been described in the GM of patients with MS and has been linked to physical disability, Cognitive Dysfunction, and Brain Atrophy.

While this T₂ HypoIntensity is thought to represent Iron Deposition, this awaits pathologic confirmation.

Advanced MRI measures of Iron deposition such as R2, R2*, R2' relaxometry, 3T imaging and other new approaches are beginning to be applied to studies of MS and should yield interesting information.

Both T₁ and T₂ relaxometry have a role in detecting damage in NA Brain Tissue that escapes detection by conventional MRI lesion measures.

For example, T₂ mapping may allow an assessment of Myelin content in NAWM. In this review, we will focus on MRI advances in the last 10 years pertaining to T₁ and T₂ measures of diffuse GM and WM damage.

Inflammation, DeMyelination, Gliosis and Axonal Degeneration are pathological hallmarks of Multiple Sclerosis (MS) and Experimental Autoimmune Encephalomyelitis.

Axonal damage is thought to contribute to irreversible damage and functional impairment, but is difficult to quantify.

Conventional MRI has been used to assess the Inflammatory and DeMyelinating aspects of MS lesions.

But, more sensitive and specific methods are needed to identify Axonal damage to monitor disease progression and to determine efficacy of putative NeuroProtective agents.

We used high resolution Diffusion Tensor Imaging (DTI) and fiber tracking to examine the Spinal Cord in rats with focal Dorsal Column inflammatory or DeMyelinating lesions to determine.

Whether DTI measures can be used to detect pathology at the site of the focal lesion and to measure Axonal Damage in tracts distal to the focal lesion.

Distant from the focal lesion, total Axon counts, degenerating Axon counts and SMI-31 staining.

But not Luxol fast blue staining, were significantly correlated with Fractional Anisotropy, Axial Diffusivity and Radial Diffusivity, all of which are derived from the DTI data.

These data suggest that high resolution DTI may be a more sensitive method than conventional imaging for detecting Axonal Damage at sites distant from inflammation.

Background
There is growing evidence for the concept of Multiple Sclerosis (MS) as an Inflammatory-NeuroDegenerative Disease, with a different pattern of Atrophy evolution in Gray Matter (GM) and White Matter (WM) tissue compartments.

Objective
We aimed to investigate the evolution of different MRI measures in early Relapsing/Remitting (RR) MS patients and in Normal Controls (NC) over 2 years.

We also evaluated the progression of these MRI measures in a subset of patients who were followed for up to 5 years.

Methods
Included in this study were one hundred forty-seven (147) patient.

Who participated in the combination ASA (Avonex, Steroids, Azathioprine) study and completed full treatment, clinical and MRI assessment at 0, 12 and 24 months.

A subgroup of 66 patients was followed for 36 months, 51 for 48 months and 43 for 60 months, respectively.

Mean age at baseline was 30.7 years, mean disease duration was 5.5 years, mean EDSS was 1.8 and mean annualized relapse rate before study entry was 1.7.

MRI scans were performed on a 1.5T scanner every 2 months for the first 2 years and thereafter once yearly for up to 5 years.

In addition to the MS group, 27 NC were examined at months 0, 12 and 24 using the same MRI protocol.

Percent Brain Volume Change (PBVC), GM Volume (GMV), WM Volume (WMV) and Peripheral Gray Volume (PGV) were measured annually using SIENA/X software.

T₂-HyperIntense Lesion Volume (LV), Lateral Ventricle Volume (LVV), and Third Ventricle Width (3VW) were also assessed annually.

Results
Over the period of 0-24 months, MS patients lost significantly more GMV (-2.6% vs. -0.72%, p < 0.0001), PGV (-2.4% vs. -1.03%, p < 0.0001).

And PBVC (-1.2% vs. -0.22%, p < 0.0001), and increased in LVV (+16.6% vs. +0.55%, p < 0.003) and 3VW (+9.3% vs. 0, p=0.003), when compared to NC.

Within-person change in MRI measures for MS patients over 5 years was -4.2% for PBVC, -6.2% for GMV, -5.8% for PGV, -0.5% for WMV (all p < 0.0001), +68.7 for LVV (p < 0.00001), +4% for 3VW (p < 0.00001) and +42% for T₂-LV (p < 0.0001).

Conclusions
Our study confirmed a different pattern of GM, WM and Central Atrophy progression over 2 years between MS patients and NC.

The study showed a different evolution of tissue compartment Atrophy measures in MS patients, with faster decline in Cortical and deep GM regions, as well as PeriVentricular WM regions over a 5-year period.

T-Cell ImmunoGlobulin- and mucin domain-containing molecule (TIM)3 is a T-Helper cell (Th1)-associated cell surface molecule that regulates Th1 responses and promotes Tolerance in mice, but its expression and function in human T-Cells is unknown.

We generated 104 T-Cell clones from the CerebroSpinal Fluid (CSF) of six patients with Multiple Sclerosis (MS) (n = 72) and four control subjects (n = 32) and assessed their Cytokine profiles and expression levels of TIM3 and related molecules.

MS CSF clones secreted higher amounts of Interferon-gamma (IFN-γ) than did those from control subjects, but paradoxically expressed lower levels of TIM3 and T-bet.

InterLeukin-12-mediated polarization of CSF clones induced substantially higher amounts of IFN-γ secretion but lower levels of TIM3 in MS clones relative to control clones, demonstrating that TIM3 expression is dysregulated in MS CSF clones.

Reduced levels of TIM3 on MS CSF clones correlated with resistance to Tolerance induced by costimulatory blockade.

Finally, reduction of TIM3 on ex vivo CD4⁺ T-Cells using small interfering (si)RNA enhanced proliferation and IFN-γ secretion, directly demonstrating that TIM3 expression on human T-Cells regulates proliferation and IFN-γ secretion.

Failure to up-regulate T-Cell expression of TIM3 in inflammatory sites may represent a novel, intrinsic defect that contributes to the pathogenesis of MS and other human Autoimmune Diseases.

alphaB-Crystallin (CRYAB) is the most abundant gene transcript present in early active Multiple Sclerosis lesions, whereas such transcripts are absent in normal Brain tissue.

This Crystallin has Anti-Apoptotic and NeuroProtective functions. CRYAB is the major target of CD4⁺ T-Cell Immunity to the Myelin sheath from Multiple Sclerosis Brain.

The pathophysiological implications of this Immune Response were investigated here.

We demonstrate that CRYAB is a potent negative regulator acting as a brake on several inflammatory pathways in both the Immune System and Central Nervous System (CNS).

CRYAB(-/-) mice showed worse Experimental Autoimmune Encephalomyelitis (EAE) at the acute and Progressive phases, with higher Th1 and Th17 Cytokine secretion from T-Cells and Macrophages, and more intense CNS inflammation, compared with their wild-type counterparts.

Furthermore, CRYAB(-/-) Astrocytes showed more cleaved Caspase-3 and more TUNEL staining, indicating an Anti-Apoptotic function of CRYAB.

AntiBody to CRYAB was detected in CerebroSpinal Fluid from Multiple Sclerosis patients and in Sera from mice with EAE. Administration of recombinant CRYAB ameliorated EAE.

Thus, the Immune Response against a negative regulator of inflammation, CRYAB, in Multiple Sclerosis, would exacerbate Inflammation and DeMyelination. This can be countered by giving CRYAB itself for therapy of ongoing disease.

Objective
To develop covariate specific short-term disability curves to demonstrate the probability of progressing by Expanded Disability Status Scale (EDSS) at semiannual visits.

Methods
Semiannual EDSS scores were prospectively collected in 218 Relapsing/Remitting (RR) and Clinically Isolated Syndrome (CIS) patients.

As part of the Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital (CLIMB) study.

Baseline Brain Parenchymal Fraction (BPF) and T₂ lesion volume were available on 205 patients.

A partial proportional odds model determined the influence of covariates on the change in EDSS score at subsequent visits.

A discrete second order Markov transitional model was fit and generated a probability matrix for each subject; the 6-month probabilities of EDSS change were graphically represented.

Results
The univariate analysis demonstrated the lowest baseline BPF quartile (OR 1.99; p = 0.0203) and the highest T₂ lesion volume quartile (OR 2.19; p = 0.0130) were associated with progression in EDSS.

Covariate specific disability curves demonstrated the effect of BPF and T₂ lesion volume on short-term progression.

In subjects with a 6-month EDSS of 2, the probability of a sustained progression of an EDSS of 3 within 3 years was 0.277 for a subject with low BPF and a high T₂ lesion volume vs 0.055 for a subject with high BPF and a low T₂ lesion volume.

Conclusions
Markov transitional models allow for the comparison of covariate specific short-term disability changes among groups of patients with Multiple Sclerosis.

Background
Participants enrolled in the North American Research Committee on Multiple Sclerosis (NARCOMS) registry report disability status using Performance Scales (PS), a self-report measure.

The bladder/bowel subscale (PSB) of PS has not been validated. It is also unknown whether ethnic or socioeconomic disparities exist in bladder care.

Objective
We aimed to validate the bladder/bowel subscale used by the NARCOMS registry and to describe urologic symptoms, investigations, and treatments received by registry participants.

Methods
In the Fall 2005 update questionnaire, we collected the Bowel Control Scale (BWCS) and Urogenital Distress Inventory-6 (UDI-6) as criterion measures and urologic investigations and treatments.

We measured associations between investigations, treatments, and symptoms with clinical and sociodemographic variables using chi(2) tests for categorical variables and Kruskal-Wallis tests for continuous variables, followed by multivariable logistic regression.

Results
Nine thousand six hundred eighty-eight participants completed the survey.

For the UDI-6, the median (interquartile range) score was 33.3 (16.7 to 50.0), for the BWCS 3 (1 to 6), and for the PSB 1 (1 to 3).

The correlation between the PSB and the UDI-6 was r = 0.67 and between the PSB and the BWCS r = 0.53 (both p < 0.0001).

Participants had increased odds of receiving medication for bladder symptoms if they had health insurance (odds ratio [OR] 1.90; 1.07 to 3.35).

Participants who were white (OR 1.5; 1.16 to 1.94) and had health insurance (OR 2.0; 1.3 to 3.07) had increased odds of undergoing urologic investigations.

Conclusion
The Performance Scales bladder question has adequate criterion and construct validity in Multiple Sclerosis (MS). There are ethnic and socioeconomic disparities in bladder management in MS.

Background
The course and prognosis of Childhood-Onset Multiple Sclerosis have not been well described.

Methods
We used data from 13 adult Neurology departments affiliated with the European Database for Multiple Sclerosis (EDMUS) network.

To identify a cohort of 394 patients who had Multiple Sclerosis with an onset at 16 years of age or younger and a comparison group of 1775 patients who had Multiple Sclerosis with an onset after 16 years of age.

We determined the initial clinical features, the dates of disease onset, and the occurrence of outcomes, including relapse, conversion to secondary progression, and irreversible disability as measured by scores of:

1. 4 (limited walking ability but ability to walk more than 500 m without aid or rest),

2. 6 (ability to walk with unilateral support no more than 100 m without rest), and

3. 7 (ability to walk no more than 10 m without rest while using a wall or furniture for support) on the Kurtzke Disability Status Scale (range, 0 to 10; higher scores indicate more severe disability).

Results
For patients with Childhood-Onset Multiple Sclerosis, the estimated median time from onset to Secondary Progression was 28 years, and the median age at conversion to Secondary Progression was 41 years.

The median times from onset to disability scores of 4, 6, and 7 were 20.0, 28.9, and 37.0 years, respectively, and the corresponding median ages were 34.6, 42.2, and 50.5 years.

In comparison with patients with adult-onset disease, those with Childhood-Onset Disease were more likely to be female than male (female:male ratio, 2.8 vs. 1.8), were more likely to have an Exacerbating/Remitting initial course (98% vs. 84%).

Took approximately 10 years longer to reach Secondary Progression and irreversible disability, and reached these landmarks at an age approximately 10 years younger (P < 0.001 for all comparisons).

Conclusions
Patients with Childhood-Onset Multiple Sclerosis take longer to reach states of irreversible disability but do so at a younger age than patients with adult-onset Multiple Sclerosis.

Objective
Recent studies in Peripheral Blood Mononuclear Cells (PBMCs) have indicated that exacerbations of Multiple Sclerosis (MS) could be associated with the reactivation of latent Varicella-Zoster Virus (VZV).

Methods
Ultrastructural observations for Viral particles were made by electron microscopy in CerebroSpinal Fluid (CSF) from 15 MS patients during relapse, 19 MS patients during remission, and 28 control subjects.

Initial findings were reproduced in a confirmation cohort.

In addition, DNA from VZV was quantified by real-time polymerase chain reaction in PBMCs and CSF from a large number of MS patients (n = 78).

Results
We found by electron microscopy the presence of abundant Viral particles identical to VZV in CSF obtained from MS patients within the first few days of an acute relapse.

In contrast, Viral particles were not seen in CSF samples from MS patients in remission or from Neurological control subjects.

Also, DNA from VZV was present in CSF and in PBMCs during relapse, disappearing in most patients during remission.

The mean Viral load was 542 times greater in CSF at relapse than in CSF at remission and 328 times greater in CSF at relapse than in PBMCs at relapse.

Interpretation
The UltraStructural finding of Viral particles identical to VZV, together with the simultaneous presence of large quantities of DNA from VZV in the SubArachnoid Space, almost restricted to the periods of exacerbation.

As well as its steady diminution and eventual disappearance from clinical relapse to clinical remission are surprising and constitute the strongest evidence to support the participation of VZV in the pathogenesis of MS.

Ann Neurol 2008.