MS Abstracts 03c-2g5

Background
Although patients with Multiple Sclerosis (MS) are advised to stop Interferon-beta-1a (IFN-ß-1a) therapy before becoming pregnant, some patients become pregnant while on treatment.

Methods
We examined individual patient data from eight clinical trials with IFN-ß-1a.

Results
Of 3,361 women in the studies, 69 pregnancies were reported, of which 41 were patients receiving (or who had stopped receiving within 2 weeks prior to conception) IFN-ß-1a (in utero exposure group), 22 were patients who discontinued IFN-ß-1a treatment more than 2 weeks before conception (previous exposure group), and six were patients receiving placebo.

The 41 in utero exposure pregnancies resulted in 20 healthy full-term infants, one healthy premature infant, nine induced abortions, eight spontaneous abortions, one fetal death, and one congenital anomaly (Hydrocephalus). One patient was lost to follow-up.

The 22 previous exposure pregnancies resulted in 20 full-term healthy infants, one healthy premature infant, and one birth-related congenital anomaly (Erb palsy).

Conclusions
The majority (21/31) of pregnancies that had the potential to go to full term produced healthy infants.

The rate of spontaneous abortion was higher, but not significantly so, in the in utero exposure group compared to general population estimates.

Until more exposure data become available, patients remain advised to stop IFN-ß therapy before becoming pregnant.

Clinical Diffusion Magnetic Resonance (MR) imaging in humans started in the last decade with the demonstration of the capabilities of this technique of depicting the anatomy of the White Matter Fibre Tracts in the Brain.

Two main approaches in terms of reconstruction and evaluation of the images obtained with application of Diffusion sensitizing gradients to an Echo Planar imaging sequence are possible.

The first approach consists of reconstruction of images in which the effect of White Matter Anisotropy is averaged - known as the Isotropic or Diffusion weighted images, which are usually evaluated subjectively for possible areas of increased or decreased signal, reflecting restricted and facilitated Diffusion, respectively.

The second approach implies reconstruction of image maps of the Apparent Diffusion Coefficient (ADC), in which the T₂ weighting of the Echo Planar Diffusion sequence is cancelled out, and their objective, i.e. numerical, evaluation with Regions Of Interest or Histogram analysis.

This second approach enables a quantitative and reproducible assessment of the Diffusion changes not only in areas exhibiting signal abnormality in conventional MR images but also in areas of normal signal.

A further level of image post-processing requires the acquisition of images after application of sensitizing gradients along at least 6 different spatial orientations and consists of computation of the Diffusion Tensor and reconstruction of maps of the Mean Diffusivity (D) and of the White Matter Anisotropic properties, usually in terms of Fractional Anisotropy (FA).

Diffusion-weighted imaging is complementary to conventional MR imaging in the evaluation of the acute Ischemic Stroke.

The combination of Diffusion and Perfusion MR imaging has the potential of providing all the information necessary for the diagnosis and management of the individual patient with acute Ischaemic Stroke.

Diffusion-weighted MR, in particular quantitative evaluation based on the Diffusion Tensor, has a fundamental role in the assessment of Brain maturation and of White Matter diseases in the fetus, in the neonate and in the child.

Diffusion MR imaging enables a better characterisation of the lesions demonstrated by conventional MR imaging, for instance in the Hypoxic-Ischaemic Encephalopathy, in infections and in the inherited metabolic diseases, and is particularly important for the longitudinal evaluation of these conditions.

Diffusion-weighted MR imaging has an established role in the differential diagnosis between Brain abscess and cystic Tumor and between epidermoid Tumor and Arachnoid cyst.

On the other hand, the results obtained with Diffusion MR in the characterisation of type and extension of Glioma do not yet allow decision making in the individual patient.

Diffusion is one of the most relevant MR techniques to have contributed to a better understanding of the pathophysiological mechanisms of Multiple Sclerosis (MS).

In fact, it improves the specificity of MR in characterising the different pathological substrata underlying the rather uniform lesion appearance on the conventional images and enables detection of damage in the Normal-Appearing White and Gray Matter.

In MS patients the ADC or D values in the Normal-Appearing White Matter are increased as compared to control values, albeit to a lesser degree than in the lesions demonstrated by T₂-weighted images.

In addition, the D of the Normal-Appearing Gray Matter is increased in MS patients and this change correlates with the Cognitive deficit of these patients.

Histogram analysis in MS patients shows that the peak of the Brain D is decreased and right-shifted, reflecting an increase of its value, and the two features correlate with the patient's clinical disability.

Ageing is associated to a mild but significant increase of the Brain ADC or D which is predominantly due to changes in the White Matter.

Region Of Interest and Histogram studies have demonstrated that D or ADC are increased in either the areas of Leukoaraiosis or the Normal-Appearing White Matter in patients with inherited Cerebral autosomal dominant Arteriopathy with SubCortical Infarcts and Stroke or sporadic Ischemic LeukoEncephalopathy.

Diffusion changes might be a more sensitive marker for progression of the disease than conventional imaging findings.

In NeuroDegenerative Diseases of the Central Nervous System such as Alzheimer's Disease, Huntington's Disease, Hereditary Ataxias and Motor Neuron Disease, quantitative Diffusion MR demonstrates the Cortical and SubCortical Gray Matter damage.

Which is reflected in a regional increase of D or ADC, but also reveals the concomitant White Matter changes that are associated with an increase in D or ADC and decrease in FA.

In all these diseases the Diffusion changes are correlated to the clinical deficit and are potentially useful for early diagnosis and longitudinal evaluation, especially in the context of pharmacological trials.

Background
There is an increasing body of evidence that Magnetic Resonance Imaging-occult tissue damage is an important component of Primary/Progressive Multiple Sclerosis (PPMS) pathology.

Proton Magnetic Resonance Spectroscopy (1H-MRS) can be used to measure in vivo Whole-Brain N-AcetylAspartate (WBNAA) concentrations, the decrease of whose levels is considered a marker of Neuronal-Axonal injury.

Objectives
To study WBNAA 1H-MRS as a tool to provide information about irreversible Brain damage in PPMS and to investigate the relationship between WBNAA and other Magnetic Resonance Imaging measures of MS disease burden, including Brain Atrophy.

Methods
The following Magnetic Resonance pulse sequences of the Brain were obtained from 32 patients with PPMS and 16 age-matched healthy subjects: (1) Dual-Echo Turbo Spin-Echo; (2) T₁-weighted Spin-Echo; and (3) 1H-MRS to measure WBNAA concentration.

Brain total Lesion Volumes were measured. Normalized Brain Volumes were calculated using a fully automated technique. Absolute WBNAA amounts were calculated using a phantom replacement method and were then corrected for individual subjects' Brain size.

Results
Levels of WBNAA concentrations and Normalized Brain Volumes were significantly lower in patients with PPMS (mean values, 10.2 mm and 1500.0 mL, respectively) than in healthy controls (mean values, 12.9 mm and 1585.2 mL).

Both WBNAA concentrations and Normalized Brain Volumes were included as independent factors in the final model of a multivariable analysis predicting the subjects' condition.

No significant correlations were found between WBNAA values and normalized Brain Volumes, WBNAA and T₂-weighted or T₁-weighted lesion volumes.

Conclusions
Axonal-Neuronal damage in the Brain of patients with PPMS seems to occur, at least partially, independently of the burden of Magnetic Resonance Imaging-visible lesions.

Whole-Brain N-AcetylAspartate values and Normalized Brain Volumes were unrelated in this cohort, thereby suggesting that 1H-MRS and Atrophy assessment may provide in vivo complementary information about the actual extent of Brain damage in PPMS.

The Spinal Cord is frequently involved in Multiple Sclerosis (MS), and Cord damage may be an important contributor to disability. Diffusion Tensor Magnetic Resonance Imaging (DT-MRI) provides quantitative information about the structural and orientational features of the Central Nervous System.

In order to assess whether Diffusion Tensor-derived measures of Cord tissue damage are related to clinical disability, Mean Diffusivity (MD) and Fractional Anisotropy (FA) Histograms from the Cervical Cord were acquired from a large cohort of MS patients.

Diffusion-weighted sensitivity-encoded (SENSE) Echo Planar images of the Cervical Cord, and Brain Dual-Echo and Diffusion-weighted scans were acquired from 44 patients with MS and 17 healthy controls.

Cord and Brain MD and FA Histograms were produced. An analysis of variance model, adjusting for Cord volume and patient age, was used to compare Cord DT-MRI parameters from controls and patients.

A multivariate linear regression model was used to identify DT-MRI variables independently associated with disability.

Average Cervical Cord FA was significantly lower in MS patients compared to controls. Cord Cross-Sectional Area, average FA and average MD were all significantly correlated with the degree of disability (r values ranging from 0.36 to 0.51).

The multivariate linear regression model retained average Cord FA and average Brain MD as variables independently associated with disability, with a correlation coefficient of 0.73 (P < 0.001). DT-MRI reveals a loss of Cervical Cord tissue structure in MS patients.

The strong correlation found between a composite DT-MRI score and disability suggests that a full and accurate assessment of Cervical Cord damage in MS provides information that usefully contributes to an explanation of the clinical manifestations of the disease.

Background
Magnetic resonance imaging (MRI) studies in Primary/Progressive Multiple Sclerosis (PPMS) have shown a reduced frequency of enhancement with the contrast agent Gadolinium-DTPA (Gd-DTPA), in comparison with Relapsing/Remitting Multiple Sclerosis (RRMS).

And it has been suggested that there may be a less important role for inflammation in its pathogenesis.

However, the earliest clinical stages of PPMS have not been studied and thus it has not been possible to exclude the existence of an early inflammatory phase.

Objective
To study the presence, characteristics, and implications of inflammation in early PPMS.

Methods
45 patients with a mean disease duration of 3.3 years had triple dose Gd enhanced MRI, Expanded Disability Status Scale (EDSS), and Multiple Sclerosis Functional Composite (MSFC) assessments at baseline.

Repeat MRI was done at 1 and 2 months in 24 patients, and at 6 months in 38.

Results
Enhancing Brain lesions were present in 42% of patients at baseline but enhancing Cord lesions were uncommon (7%); 85% of enhancing lesions enhanced for one month or less.

Patients with enhancing lesions had greater disability (EDSS, p = 0.027; MSFC, p = 0.026) and more MRI abnormalities (greater T₂ load, p = 0.008; greater T₁ HypoIntensity load, p = 0.001.

And reduced partial Brain Volume, p = 0.012) than those without enhancement.

Enhancement at 6 months was seen in 32% of patients and was restricted to a subset of patients who enhanced at baseline.

Conclusions
Enhancement is present in some cases of early PPMS and is associated with greater disease impact in terms of both clinical and MRI measures.

Chronic Fatigue Syndrome (CFS) is a heterogeneous disorder of unknown Etiology characterized by debilitating fatigue, along with other symptoms, for at least 6 months.

Many studies demonstrate probable involvement of the Central and Autonomic Nervous System, as well as a state of generalized Immune activation and selective Immune dysfunction in patients with CFS.

The aim of this study was to compare the Lymphocyte subsets of patients with Chronic Fatigue Syndrome to those of patients with Major Depression and Multiple Sclerosis as well as those of healthy control subjects.

No differences were found in total numbers of T-Cells, B-Cells or Natural Killer (NK) Cells.

However, differences were found in T, B and NK cell subsets. Patients with Major Depression had significantly fewer resting T (CD3⁺/CD25^-) Cells than the other groups.

Patients with Major Depression also had significantly more CD20⁺/CD5⁺ B-Cells, a subset associated with the production of AutoAntiBodies. Compared to patients with Multiple Sclerosis, patients with CFS had greater numbers of CD16⁺/CD3^- NK Cells.

Further study will be required to determine whether these alterations in Lymphocyte subsets are directly involved in the pathophysiology of these disorders, or are secondary effects of the causal agent(s).

Objective
Excitatory Amino Acid Receptors are involved in the normal physiology of the Brain, and may play a role in the pathogenesis of Neurological Disorders such as Huntington's Disease, Parkinson's Disease, Amyotrophic Lateral Sclerosis, etc.

It has been demonstrated that the blockade of one of these Receptors ameliorates the symptoms of Experimental Allergic Encephalomyelitis, an animal model of Multiple Sclerosis (MS).

In a recent study, a decreased level of Kynurenic Acid was found in the CerebroSpinal Fluid of patients with MS. The only known endogenous excitotoxin Receptor antagonist is the Tryptophan metabolite Kynurenic Acid.

Another metabolite is Quinolinic Acid, which exerts different action: it is an ExcitoToxin Receptor Agonist. The ratio of these two metabolites is determined by the activities of Kynurenine AminoTransferase I and II (KAT I and KAT II).

In this study, we measured the activities of these Enzymes and the concentration of Kynurenic Acid in the Red Blood Cells (RBC) and in the plasma of patients with MS. KAT activities were detected both in the RBC and in the plasma.

As compared with the control subjects, the KAT I and KAT II activities were significantly higher in the RBC of the patients. The concentration of Kynurenic Acid is elevated in the plasma of MS patients, and there is a tendency to an elevation in the RBC.

These changes may indicate a compensatory protective mechanism against Excitatory NeuroToxic effects. Our data demonstrate the involvement of the Kynurenine System in the pathogenesis of MS, which may predict a novel therapeutic intervention.

Three hundred seven patients with MS and 300 controls were genotyped for G98T and A561C SNPs in the E-Selectin gene, and genetic data were correlated with the course of the disease.

The frequency of the T/T genotype of the G98T SNP was significantly increased in RR-MS patients compared with controls, while was absent in PP-MS. The frequency of the A561C SNP was significantly decreased in SP-MS compared with Benign RR-MS.

The T/T genotype of the G98T SNP is likely to confer an increased risk to develop MS. The A561C polymorphism seems to act as protective factor towards the progression to SP-MS.

Background
Debate continues concerning the relevance of Neutralizing AntiBody (NAB) development on the efficacy of Interferon (IFN) therapy in patients with Multiple Sclerosis (MS).

The PRISMS (Prevention of Relapses and Disability by Interferon-beta-1a Subcutaneously in Multiple Sclerosis) Study of subcutaneous IFN-ß-1a showed significant benefit on all efficacy outcomes.

With no significant impact from NAB development on relapses at 2 years. The 2-year extension permitted longer observation following NAB development.

Methods
Exploratory post-hoc analyses of pharmacodynamic response and clinical and MRI outcomes were performed on data from 368 patients with Relapsing MS treated with IFN from study start, based on NAB status.

Results
Persistent Nabs, above 20 NU/mL, were present in 14% of the 44-microg three times weekly (TIW) and 24% of the 22-microg TIW group over 4 years. NAB development was associated with reduced pharmacodynamic marker induction at 1 year.

Over the entire 4 years of study, relapse and disability measures were similar between NAB+ and NAB- patients.

However, once NABs developed, significant differences were noted between NAB+ and NAB- groups, particularly on MRI and relapse measures. The presence of binding AntiBodies alone did not affect outcome.

Conclusion
Neutralizing AntiBody development in Interferon-treated patients is correlated with reduced efficacy and is a potential cause for renewed disease activity.

Background
Neutralizing AntiBodies (NABs) occur frequently in patients receiving Interferon-beta (IFN-ß) for Multiple Sclerosis (MS), but it is unclear whether occurrence of NABs is predictive for the persistence of NABs during continued IFN-ß therapy.

Methods
The authors used an antiviral neutralization bioassay to measure NABs blindly from 6 months up to 78 months in patients with MS who were followed for at least 24 months during treatment with IFN-ß.

Patients were classified into three groups:
1. Persistently NAB-negative patients, defined as patients without any positive samples at any time
2. Definitely NAB-positive patients, defined as patients who had at least two consecutive positive samples; and
3. Patients with fluctuating NAB-positive and NAB-negative samples

Results
A total of 455 patients were included in the study. Overall, 52.3% of the patients were persistently NAB-negative, 40.9% became definitely NAB-positive, and the remaining 6.8% were fluctuating.

More patients treated with IFN-ß-1a (Avonex) remained NAB-negative (p < 0.0001), whereas there was no difference between IFN-ß-1b (Betaferon) and IFN-ß-1a (Rebif).

Patients who have remained NAB-negative during the first 24 months of therapy rarely developed NABs. On the contrary, the majority of patients, who had been NAB-positive from 12 through 30 months after start of therapy, remained NAB-positive.

Conclusions
NABs should be measured in all patients treated with IFN-ß. If patients have been persistently NAB-negative for 24 months, measurements can be discontinued.

Patients who have been NAB-positive for a period of 18 months or more usually remain NAB-positive for a long time.

Our objectives were to determine the reproducibility of Diffusion Tensor Imaging (DTI) in volunteers.

And, to evaluate the ability of the method to monitor longitudinal changes occurring in the Normal-Appearing White Matter (NAWM) of patients with Multiple Sclerosis (MS).

DTI was performed three-monthly for one year in seven MS patients: three Relapsing/Remitting (RRMS), three Secondary/Progressive (SPMS) and one Relapsing SP.

They were selected with a limited Cerebral lesion load. Seven age- and sex-matched controls also underwent monthly examinations for three months.

Diffusivity and Anisotropy were quantified over the segmented whole SupraTentorial White Matter, with the indices of Diffusion Trace (Tr) and Fractional Anisotropy (FA).

Results obtained in volunteers show the reproducibility of the method. Patients had higher Trace and lower Anisotropy than matched controls (P < 0.0001).

Over the follow-up, both Tr and FA indicated a recovery after the acute phase in RRMS and a progressive shift towards abnormal values in SPMS.

Although this result is not statistically significant, it suggests that DTI is sensitive to microscopic changes occurring in tissue of normal appearance in conventional images.

And could be useful for monitoring the course of the disease, even though it was unable to clearly distinguish between the various PhysioPathological processes involved.

Since the first attempts to understand the mechanisms of learning, memory, development, and other instances of NeuroPlasticity, Gene expression has been an attractive explanation for the persistence of such processes.

It has been hypothesized that changes in the levels of expression of a Gene, or a coordinated set of Genes, would be necessary for dramatic structural changes like the growth of new Neurites.

And more subtle BioChemical changes at existing Synapses might also result from an alteration in the array of Gene products being manufactured in the relevant cells.

However, a great deal of what is classified as NeuroPlasticity is dependent on primary changes in ElectroPhysiological activity or other conditions at Synapses.

Therefore, a seminal question to those interested in the molecular underpinnings of NeuroPlasticity is that of signal transduction:

How do changes in Synaptic activity get communicated to the Nucleus?

To many who learn about the regulation of the transcription factor NFkappaB with this question in mind, its utility seems clear.

Furthermore, NFkappaB is an important signaling factor for Cytokines that appear to participate in several pathological conditions (e.g., Parkinson's Disease, Multiple Sclerosis, and Depression).

So, understanding its mechanisms of action and its relationship to other elements of Cytokine signaling may be fundamental to determining the role of the Inflammatory System in Psychiatric and NeuroDegenerative conditions.

For these reasons, NFkappaB has garnered considerable attention in various aspects of NeuroPlasticity, from long-term potentiation to the most dramatic forms of Plasticity: cell birth and death.

In a few cases, elegant experimental design has resulted in convincing evidence for the involvement of NFkappaB in specific phenomena.

However, the complexity of this transcription factor-including confusion over what exactly is meant by "NFkappaB"-has led to some misleading conclusions, as well.

This chapter highlights some of the potential red herrings to be encountered in the study of NFkappaB and will summarize the data and interpretations in which some degree of confidence can be placed.

The final answers will depend on the application of models and tools only now in development.