Acyclovir treatment of relapsing-remitting multiple sclerosis. A randomized, placebo-controlled, double-blind study

A randomized clinical trial of valacyclovir in multiple sclerosis

OBJECTIVE

The human Herpesvirus type-6 (HHV-6) has been implicated in multiple sclerosis (MS). Valacyclovir is an antiviral agent with an excellent safety profile. A two-year placebo-controlled, double-blind study was conducted to (1) ascertain if high-dose, prolonged treatment with valacyclovir would be safe and (2) observe if valacyclovir would delay the progression of MS clinically or by magnetic resonance imaging (MRI).

DESIGN/METHODS

Fifty-eight patients were stratified as to severity and randomly assigned to receive valacyclovir (3000 mg/day) or placebo for a period of two years. Patients were followed clinically over the two-year period by means of the Expanded Disability Status Scale (EDSS), the Ambulation Index (AI) and brain MRI scans. Patients underwent routine lab studies every three months. Patients continued on the medication for two years unless they had a sustained progression or repeated exacerbations.

RESULTS

No patient discontinued the study due to side effects or toxicity. In Relative Ranking of Progression, time to first attack, attack rate, and time to withdrawal there were trends (but not statistically significant) toward drug effect over placebo in the Severe clinical category. MRI evaluation showed no significant drug effect.

CONCLUSIONS

Although not statistically significant, positive trends were detected for acyclovir by clinical measures, but not by MRI.

Update on human herpesvirus 6 biology, clinical features, and therapy

Human herpesvirus 6 (HHV-6) is a betaherpesvirus that is closely related to human cytomegalovirus. It was discovered in 1986, and HHV-6 literature has expanded considerably in the past 10 years. We here present an up-to-date and complete overview of the recent developments concerning HHV-6 biological features, clinical associations, and therapeutic approaches. HHV-6 gene expression regulation and gene products have been systematically characterized, and the multiple interactions between HHV-6 and the host immune system have been explored. Moreover, the discovery of the cellular receptor for HHV-6, CD46, has shed a new light on HHV-6 cell tropism. Furthermore, the in vitro interactions between HHV-6 and other viruses, particularly human immunodeficiency virus, and their relevance for the in vivo situation are discussed, as well as the transactivating capacities of several HHV-6 proteins. The insight into the clinical spectrum of HHV-6 is still evolving and, apart from being recognized as a major pathogen in transplant recipients (as exemplified by the rising number of prospective clinical studies), its role in central nervous system disease has become increasingly apparent. Finally, we present an overview of therapeutic options for HHV-6 therapy (including modes of action and resistance mechanisms).

Combination therapy for multiple sclerosis: the treatment strategy of the future?

Multiple sclerosis (MS) is an inflammatory autoimmune disease characterised by demyelination and axonal loss in the CNS. Although new immunomodulatory therapies including interferon-beta and glatiramer acetate became available during the last decade, these therapies are only partially effective. There is a continuing need to develop more effective treatment strategies to combat the chronic and progressive aspects of the disease. In view of the complex pathophysiology underlying the MS disease process, combination therapy offers a rational therapeutic approach. Combining immunomodulatory agents with different mechanisms of action that promote synergistic or additive effects represents an important objective in MS therapeutic research. Ultimately, the optimal therapies will likely include strategies that promote repair and limit tissue destruction in combination with anti-inflammatory interventions.

No correlation between number of MRI-evident lesions in cerebrum and the soleus stretch reflex in multiple sclerosis patients

The aim of the study was to investigate if the stretch reflex of the soleus muscle was useful in quantifying upper motor neuron lesions. The soleus stretch reflex was recorded in 10 healthy subjects and 20 patients with active relapsing-remitting multiple sclerosis and correlated to the number of MRI lesions in cerebrum and clinical scores (expanded disability status scale and regional functional scoring system). The short latency stretch reflex was elicited by rotating the left ankle joint 4 degrees with a rise time in the interval of 40-640 ms. The amplitude of the stretch was larger in multiple sclerosis patients being 88.5 microV in patients and 12.8 microV in controls, P = 0.007. The sensitivity of the stretch reflex expressed as the slope of the best linear fit was increased in MS patients to 2.6 microVs/degree compared with 0.6 microVs/degree (0.1-2.2) in controls, P = 0.009. There was no correlation between amplitude of the stretch reflex and number of MRI lesions (r = -0.03). In conclusion, the soleus stretch reflex might be useful to quantify spasticity but is not useful in detecting dysfunction of upper motor neurons in MS.

Multicentre, randomised, double blind, placebo controlled, phase III study of weekly, low dose, subcutaneous interferon beta-1a in secondary progressive multiple sclerosis

OBJECTIVE

Interferon (IFN) beta has repeatedly shown benefit in multiple sclerosis (MS) in reducing the rate of relapse, the disease activity as shown with magnetic resonance imaging and, to some degree, the progression of disability; however, it is unknown how much the therapeutic response depends on the dose, the subgroup involved, and the disease stage. This multicentre, double blind, placebo controlled study explored the dose-response curve by examining the clinical benefit of low dose IFN beta-1a (Rebif), 22 micro g subcutaneously once weekly, in patients with secondary progressive MS.

METHODS

A total of 371 patients with clinically definite SPMS were randomised to receive either placebo or subcutaneous IFN beta-1a, 22 micro g once weekly, for 3 years. Clinical assessments were performed every 6 months. The primary outcome was time to sustained disability, as defined by time to first confirmed 1.0 point increase on the Expanded Disability Status Scale (EDSS). Secondary outcomes included a sensitive disability measure and relapse rate.

RESULTS

Treatment had no beneficial effect on time to confirmed progression on either the EDSS (hazard ratio (HR) = 1.13; 95% confidence interval (CI) 0.82 to 1.57; p = 0.45 for 22 micro g v placebo) or the Regional Functional Status Scale (HR = 0.93; 95% CI 0.68 to 1.28; p = 0.67). Other disability measures were also not significantly affected by treatment. Annual relapse rate was 0.27 with placebo and 0.25 with IFN (rate ratio = 0.90; 95% CI 0.64 to 1.27; p = 0.55). The drug was well tolerated with no new safety concerns identified. No significant gender differences were noted.

CONCLUSIONS

This patient population was less clinically active than SPMS populations studied in other trials. Treatment with low dose, IFN beta-1a (Rebif) once weekly did not show any benefit in this study for either disability or relapse outcomes, including a subgroup with preceding relapses. These results add a point at one extreme of the dose-response spectrum of IFN beta therapy in MS, indicating that relapses in this phase may need treatment with higher doses than in the initial phases.

B cells in multiple sclerosis

The most common laboratory abnormality in multiple sclerosis (MS) is an increased amount of cerebrospinal fluid IgG and the presence of oligoclonal bands. Despite studies of the humoral response that suggest the involvement of an infectious agent or autoantigen in disease, the major targets of the oligoclonal response are still unknown. Identification of these targets will reveal valuable insights into the cause and pathogenesis of MS and is likely to lead to effective treatment.

Long-term follow up of patients with clinically isolated syndromes, relapsing-remitting and secondary progressive multiple sclerosis

This paper extends on previous data on prognosis in multiple sclerosis (MS), to encompass the entire course of the disease. The first episode suggestive of MS [the clinically isolated syndrome (CIS)] was included as a starting point, and the speed of secondary progression as an end point. Primary progressive MS was not included. Unique preconditions, with one neurological service covering the Göteborg district, allowed for establishing a strictly population-based, essentially untreated 15-year incidence cohort of 308 MS patients who were followed for 25 years. Survival analysis was performed as Kaplan-Meyer graphs, and independent predictors were ascertained by Cox regression analysis. A matrix of several predictors and end points was created. From CIS, a higher risk of developing clinically definite MS (CDMS), secondary progressive course and Disability Status Scale 7 (DSS7) was predicted by efferent tract lesions. However, less than 25% had reached DSS7 25 years after CIS with pure afferent lesions or other favorable predictors. During the first five years, higher relapse frequency, as well as incomplete remission of early bouts, predicted higher risks of secondary progressive course and DSS7 during follow-up to 25 years. However, these early predictors were unable to predict the rate of progression, which seems to contain an element of the disease process unassociated with its early events. Only late predictors, such as a shorter time from onset to secondary progression (1-10 years) and a higher number of functional systems involved at onset of progression predicted a faster progression rate. Predictors from this study could be used to refine historically controlled trials.

Hit-Hit and hit-Run: viruses in the playing field of multiple sclerosis

Viruses have been major players in the search for the cause of multiple sclerosis (MS). In support of the viral theory is the predominance of CD8+ T cells and class-I major histocompatibility complex in lesions, the powerful therapeutic effects of beta interferons, the ease of inducing demyelination in experimental models following virus challenge, and the documented examples of several human demyelinating diseases conclusively demonstrated to be of viral origin. We propose two hypotheses of how viruses may cause MS. In the "Hit-Hit" hypothesis, the virus persists or may be reactivated in the central nervous system (CNS). Injury is the result of direct viral damage and by an attempt of the immune response to clear the infectious agent. In the "Hit-Run" hypothesis, virus infects the periphery but never enters the CNS. The virus sets up an abnormal immunologic milieu for subsequent autoimmunity. In both scenarios, knowing the inciting virus would be expected to eliminate disease if the population were vaccinated to prevent infection. In the treatment of patients with fully established disease, the Hit-Hit hypothesis would require that antiviral agents enter the CNS and stop replication. In the case of the Hit-Run hypothesis, treatment of patients with established disease with antiviral agents would be futile.

Tomorrow's challenges for herpesvirus management: potential applications of valacyclovir

Controlled trials suggest that acyclovir/valacyclovir can provide significant clinical benefits when used for prophylaxis in the immunocompromised host. These findings implicate herpesvirus(es) in the pathogenesis of complex medical conditions, including graft rejection and death. However, it is not known which of the 8 herpesviruses are important under particular circumstances. Prime candidates for triggering adverse outcomes are cytomegalovirus (CMV) in solid organ transplant recipients (causing rejection), CMV and human herpesvirus type 6 (HHV-6) in bone marrow transplant patients (causing marrow suppression), and herpes simplex virus, HHV-6, and CMV in AIDS patients (accelerating the rate of human immunodeficiency virus disease progression and death). Other diseases that may have a herpesvirus component or trigger susceptible antiviral agents include atherosclerosis and multiple sclerosis. In the future, clinicians should be alert to novel findings of randomized trials that may provide insight into the pathogenesis of these diseases and the contributions made by clinically silent herpesvirus infections.

[Atherosclerosis, multiple sclerosis, and Alzheimer's disease: what role for Herpesviridae?]

Herpesviridae are ubiquitous, and are commonly involved in well identified diseases as genital herpes, chickenpox and herpes zoster, infectious mononucleosis, exanthem subitum... They are responsible for latent and chronic infections after primary infection. Atherosclerosis, multiple sclerosis, Alzheimer's disease are diseases which are very different, and for which pathogenesis remains unknown. Several authors have hypothesized that Herpesviridae could play a role in such diseases. The present paper reviews arguments not only in favour but also against such hypothesis. Any formal conclusion is impossible, and more extensive studies are warranted.

Anti-viral properties of interferon beta treatment in patients with multiple sclerosis

Viral infections are potentially associated with the etiology and pathogenesis of multiple sclerosis (MS). It has been speculated that the treatment efficacy of interferon beta (IFN beta) in MS may relate to its anti-viral properties. The study was undertaken to evaluate the in vivo anti-viral effects of IFN beta-1a in patients with MS. Human herpesvirus-6 (HHV-6) was studied as an example for being a latent neurotropic virus. IFN beta used at concentrations of approximately 0.5 microg/ml was shown to significantly reduce in vitro HHV-6 replication in a susceptible T-cell line. Sera derived from 23 MS patients treated with IFN beta-1a were examined for serum cell-free DNA of HHV-6 as an indicator for viral replication and the reactivity of IgM antibodies to a recombinant HHV-6 virion protein containing a known immunoreactive region. The results were compared with those of control sera obtained from untreated MS (n=29) and healthy individuals (n=21). The findings indicated that IFN beta treatment significantly reduced HHV-6 replication as evident by decreased cell-free DNA in treated MS specimens. The results correlated with decreased IgM reactivity to the HHV-6 antigen in treated MS patients compared to untreated controls, suggesting reduced exposure to HHV-6. The findings were confirmed in paired sera obtained from seven MS patients before and after the treatment The study provides new evidence indicating that IFN beta has potent in vivo anti-viral effects that may contribute to the treatment efficacy in MS.

Serological differences in monozygotic twin pairs discordant for multiple sclerosis

OBJECTIVES

The etiology of MS is unknown but genetic factors are supported by a high concordance in twins. Geographic distribution and migration studies indicate, however, the importance of environmental factors.

MATERIAL AND METHODS

We studied 3 pairs of genetically identical twins who had shared the same environment but were discordant for MS. Serum samples were assayed for antibodies against 21 viruses, 4 bacteria and Toxoplasma gondii.

RESULTS AND CONCLUSION

No common factor present only in the affected twins was identified but differences were found in serum titers against some neurotropic microorganisms. In general the serum titers were strikingly similar in the twins, indicating no major disturbances of the humoral immune system in MS.

Human herpesvirus 6 reactivation and encephalitis in allogeneic bone marrow transplant recipients

To determine whether receipt of an investigational anti-CD3 monoclonal antibody (BC3) increased the risk of human herpesvirus 6 (HHV-6) reactivation and development of encephalitis in bone marrow transplant (BMT) recipients, persons who had and had not received BC3 were compared. Odds of HHV-6 reactivation were higher among BC3 recipients than among control patients (odds ratio, 2.5; 95% confidence interval [CI], 1.3-4.7). In addition, BC3 recipients were more likely than control patients to develop encephalitis (risk ratio [RR], 3.5; 95% CI, 1.3-9.5), and this association followed a BC3 dose-dependent relationship (P=.03, by Mantel-Haenszel chi(2) test). In a multivariable model, HHV-6 reactivation and receipt of BC3 were associated with increased risk of encephalitis (RR, 5.4; 95% CI, 1.9-15.3, and RR, 3.3; 95% CI, 1.2-9.1, respectively). In conclusion, both HHV-6 reactivation and receipt of BC3 for prophylaxis of acute graft-versus-host disease independently increased the risk of encephalitis in allogeneic BMT recipients. Prospective studies to better define the relationship between HHV-6 reactivation and encephalitis in allogeneic BMT recipients are warranted.

Human herpesvirus 6 and multiple sclerosis: systemic active infections in patients with early disease

By means of immunohistochemical staining, cells actively infected with human herpesvirus 6 (HHV-6) were found in central nervous system tissues from 8 (73%) of 11 patients with definite multiple sclerosis (MS). Interestingly, 17 (90%) of 19 tissue sections showing active demyelination were positive for HHV-6-infected cells compared with only 3 (13%) of 23 tissue sections free of active disease (P<.0001). Central nervous system tissues from 2 of 28 normal persons and patients with other inflammatory demyelinative diseases were positive for HHV-6-infected cells (P<.0001), and the 2 positive cases were diagnosed as having HHV-6 leukoencephalitis. By use of a rapid culture assay, blood samples from 22 (54%) of 41 patients with definite MS were found to contain active HHV-6 infections, compared with 0 of 61 normal controls (P<.0001). No significant difference was found between HHV-6 viremia-positive and HHV-6 viremia-negative MS patients with respect to type of disease (relapsing/remitting or progressive). In contrast, patients with active HHV-6 viremia were significantly younger and had shorter durations of disease than did HHV-6 viremia-negative patients.

Transient virus infection and multiple sclerosis

Multiple sclerosis (MS) is a chronic, demyelinating disease of the CNS in which autoimmunity to myelin plays a role in pathogenesis. The epidemiology of MS indicates that it may be triggered by a virus infection before the age of adolescence, but attempts to associate a specific virus with MS have produced equivocal results. Many studies of the aetiology of MS have postulated that a persistent virus infection is involved, but transient virus infection may provide a plausible alternative mechanism that could explain many of the inconsistencies in MS research. The most studied animal model of MS is chronic relapsing experimental autoimmune encephalomyelitis (CREAE), which is induced in susceptible animals following injection of myelin components. While CREAE cannot provide information on the initiating factor for MS, it may mimic disease processes occurring after an initial trigger that may involve transient virus infection. The disease process may comprise separate triggering and relapse phases. The triggering phase may involve sensitisation to myelin antigens as a result of damage to oligodendrocytes or molecular mimicry. The relapse phase could be similar to CREAE, or alternatively relapses may be induced by further transient virus infections which may not involve infection of the CNS, but which may involve the recrudescence of anti-myelin autoimmunity. Although current vaccines have a high degree of biosafety, it is suggested that the measles-mumps-rubella vaccine in particular could be modified to obviate any possibility of triggering anti-myelin autoimmunity.

Association between clinical disease activity and Epstein-Barr virus reactivation in MS

OBJECTIVE

To assess the potential significance of Epstein-Barr virus (EBV) reactivation in disease activity in MS patients.

METHODS

The prevalence of antibodies against herpes simplex virus type 1 (HSV-1), HSV-2, EBV, and cytomegalovirus was determined in a group of 108 MS patients and in 163 healthy control subjects. Sera were analyzed using combinations of novel assay systems employing highly purified viral and recombinant antigens. In addition, PCR for the detection of EBV DNA was performed in serial samples.

RESULTS

In contrast to the control populations, antibodies against EBV were present in 100% of MS patients. Among the tested human herpesviruses, this high extent of seropositivity was only found for EBV. Primary infection was found exclusively in the control group (3.7%), whereas serologic evidence of EBV reactivation was seen in MS patients (13. 9%) as well as control subjects (17.2%). There was no temporal coincidence between EBV reactivation and disease activity in MS patients. However, in 19 patients followed monthly for 1 year, active viral replication as measured by increased immunoglobulin (Ig) M and IgA responses to EBV early antigens (p54 + p138) and positive serum DNA was seen in 72.7% of patients with exacerbations during the study period and in none of the patients with clinically stable disease.

CONCLUSIONS

The results demonstrate an association between EBV reactivation and disease activity in MS patients over time, and suggest that EBV might play an indirect role in MS as an activator of the underlying disease process.

Epstein-Barr virus and multiple sclerosis

It has been suggested that the Epstein-Barr virus (EBV) plays a role in the etiology of multiple sclerosis (MS), but individual epidemiologic studies have been inconclusive, in part because of the high prevalence of previous infection among individuals without MS. We conducted a systematic review of case-control studies comparing EBV serology in MS patients and controls. Eight published investigations were identified, including a total of 1,005 cases and 1,060 controls. The summary odds ratio of MS comparing EBV seropositive individuals with EBV seronegative individuals was 13.5 (95% CI = 6.3-31.4). The strength and consistency of this association and the high sensitivity and specificity of EBV serology suggest that these results are not readily explained by an aspecific immune activation among MS patients. These findings support a role of EBV in the etiology of MS.

Multiple Sclerosis: Immunotherapy

Given our current knowledge, there is a need for the early institution of immunomodulatory therapy, especially for patients with poor prognostic factors (motor and cerebellar symptoms, frequent disease exacerbations, and a high level of activity on magnetic resonance imaging ). Patients who progress despite immunomodulatory therapy should be reevaluated in terms of diagnosis, development of neutralizing antibodies, or compliance. If a patient has a partial response to immunomodulatory therapy but his or her disease, as assessed by clinical and MRI criteria, remains very active, every effort should be made to modify disease progression by searching for an immunosuppressive therapy regimen before irreversible and considerable disability has accumulated. For the majority of patients, multiple sclerosis (MS) is a chronic condition. Therefore, until a curative treatment has been developed, the available repertoire of immunosuppressive or immunomodulatory treatments should be assessed with respect to the possibility of long-term use. This is particularly important for new immunosuppressive drugs, such as cladribine or mitoxantrone, or for invasive procedures, such as total lymphoid irradiation or autologous bone marrow transplantation. For the latter treatments, experience with long-term administration is not available or the potential side effects (eg, cardiotoxicity with mitoxantrone) limit the cumulative dose. These considerations may limit long-term administration and thus the general usefulness of some drugs. Even with proven efficacy, we need to define the next step once treatment has to be discontinued. We should also address whether exacerbating disease by discontinuing an effective therapy is a potential hazard. What other therapeutic options remain once the current treatment is discontinued? Answers are not readily available at the moment, but the question should influence our decisions in the selection of traditional, well-studied or new, potentially promising therapies.

Herpesviruses--a rationale for antiviral treatment in multiple sclerosis

In multiple sclerosis (MS), the extensive and long lasting search for viruses or other pathogens has hitherto failed to identify a common etiological agent. However, the beneficial effects by interferon-beta treatment in MS, although suggested to depend mainly on immunomodulation, might lend support to a viral involvement in the pathogenesis. The human herpesviruses have attracted interest since their recurrent modes of infection share some similarity with the relapsing-remitting course of MS, most members are readily detected within the brain, and several of these viruses may induce demyelination within the central nervous system in human hosts as well as in animal models. Accumulated diagnostic and epidemiological data are compatible with a role for the herpesviruses as possible cofactors rather than etiological agents, and recent studies showing early neuronal damage in MS patients focus attention on the neurotropic alpha-herpesviruses. Antiviral treatment trials with safe and effective drugs such as valaciclovir offer a possibility of testing the hypotheses concerning herpesviral involvement in MS.

Computerised volumetric analysis of lesions in multiple sclerosis using new semi-automatic segmentation software

The paper describes the application of new semi-automatic segmentation software to the task of detection of anatomical structures and lesion and their three-dimensional (3D) visualisation in 23 patients with secondary progressive multiple sclerosis (MS). The purpose is to study the correlation between magnetic resonance imaging (MRI) parameters (volumes of plaques and cerebrospinal fluid spaces) and clinical deficits (neurological deficits in the form of EDSS and RFSS scores, and neuropsychological deficits). The software operates in PC/Windows and PC/NeXTstep environments and utilises graphical user interfaces. Quantitative accuracy is measured by performing segmentation of fluid-filled syringes (relative error of 1.5%), and reproducibility is measured by intra- and inter-observer studies (3% and 7% variability, respectively). The mean volumes of MS plaques show significant correlations with the total RFSS scores (p = 0.04). Relative intracranial cerebrospinal fluid (CSF) space volumes show statistically significant correlation with EDSS scores (p = 0.01). The mean volume of MS plaques shows a significant correlation with the overall neuropsychological deficits (p = 0.03). 3D visualisation helps to understand the relationship of lesions to the surrounding brain structures. The use of semiautomatic segmentation techniques is recommended in the clinical diagnosis of MS patients.

Current immunotherapy in multiple sclerosis

The underlying pathophysiology of multiple sclerosis is presumed to be autoimmune in nature. Attempts to find an effective treatment for this common disease of the central nervous system have primarily focused on immune-mediated therapies, both immunosuppressive and immunomodulatory. The wide variety of immunological abnormalities detected in multiple sclerosis and its animal model, experimental allergic encephalomyelitis, has prompted the testing of a diverse array of drugs to be used for treatment. Recent successes in the treatment of relapsing-remitting multiple sclerosis with interferon beta and glatiramer acetate have renewed interest in and raised expectations for the effective control of this neurological disorder. Improved methodology in clinical trials, the development of surrogate markers and the availability of novel therapies bode well for more rapid advances.

Rational clinical immunotherapy for multiple sclerosis

In this article, we assess the roles and the efficacy of immunopharmacologic agents in the treatment of multiple sclerosis (MS) and other demyelinating disease syndromes. The initial clinical manifestations of demyelinating disease, immunotherapeutic goals, efficacy of individual agents, and specific immunopharmacologic recommendations are discussed. MS and other idiopathic demyelinating disease syndromes can be effectively managed with immunotherapy. Exacerbations are treatable, and the frequency and severity of exacerbations can be reduced. Although some agents have a minor effect on progression of disability, current approaches have not proved to have a major influence on treatment of progressive MS. Immunotherapy for inflammatory demyelinating disease necessitates a high degree of clinical certainty about the diagnosis. Because all available therapeutic agents have limitations and significant toxic effects, careful consideration is necessary before use. Treatment should be individualized on the basis of the clinical course of the disease and the degree of patient disability.

Diminished production of type-I interferons and interleukin-2 in patients with multiple sclerosis

Several lines of evidence have supported the role of immunological mechanisms in the pathogenesis of multiple sclerosis (MS) and new immunomodulatory strategies for its treatment, e.g. subcutaneous application of interferon (IFN)-beta, have emerged. We investigated the ability of peripheral blood mononuclear cells (PBMC) in 21 consecutive patients with clinically definite MS to produce interferons and lymphokines in response to viral or mitogenic stimulation. Ten patients showed clinical signs of disease activity (acute relapse) and 11 patients were in a stable condition. Additionally, white blood count, leukocyte differentiation and lymphocyte subtyping were performed. A group of age-related healthy blood donors served as control (n=20). There was no difference between patients and controls in the production of IFN-gamma, tumor necrosis factor (TNF)-alpha and soluble interleukin (IL)-2 receptor. IFN-alpha and IFN-beta responsiveness, however, was significantly lower in patients with stable disease than in patients with active disease and controls (p<0.001). Furthermore, secretion of IL-2 after stimulation was significantly diminished in both patient groups as compared to the control group (p<0.01). Analysis of T-cell subsets revealed a significantly lower amount of CD8+ T-cells in patients with stable disease, leading to a significantly higher CD4/CD8 ratio in this group as compared to patients with active disease. Our study depicted an IL-2 deficiency in MS patients which is shared with other autoimmune diseases. In addition, our findings suggest that the ability to produce type-I IFNs, IFN-alpha and IFN-beta, is primarily impaired in MS patients and changes in correlation to the course of disease activity.

Absence of seven human herpesviruses, including HHV-6, by polymerase chain reaction in CSF and blood from patients with multiple sclerosis and optic neuritis

Several members of the herpesvirus family have been implicated in the pathogenesis of multiple sclerosis (MS). Recently, HHV-6 viral antigen has been demonstrated in association to MS plaques, as well as DNA from human herpesvirus 6 (HHV-6) in cerebrospinal fluid from a few MS patients by polymerase chain reaction (PCR). In the present study, CSF from patients with MS, optic neuritis and other neurological diseases, as well as consecutive CSF and serum samples from MS patients included in a clinical trial with acyclovir, were analysed by nested PCR for the presence of DNA from herpes simplex virus 1 and 2, Epstein-Barr virus, varicella zoster virus, cytomegalovirus, human herpesvirus 6 and 7. No virus DNA was found in any CSF (n = 115) or serum (n = 116) sample. These findings argue against a continuous disseminated herpesvirus infection in MS, but do not rule out a lesion-associated, low-grade herpesvirus infection within the MS brain.

The MS Impairment Scale: a pragmatic approach to the assessment of impairment in patients with multiple sclerosis

We developed a measurement scale for assessment of impairment in MS patients (MSIS) in accordance with the recommendations of WHO. The items were kept close to a standard neurologic examination, and a short battery of cognitive tests was added. Normality was assigned to the value, zero, and the theoretical maximum score was 204. Two-hundred and ten multiple sclerosis (MS) patients were rated by one neurologist on the MS impairment Scale (MSIS), the Extended Disability Status Scale (EDSS), and the Ambulation Index (AI). The median MSIS score was 52 (5-147), the median EDSS 6.5 (1-9.5), and the median AI 5 (1-5). The relation between the MSIS scores and the EDSS was best described by an exponential function (non-linear regression coefficient, R = 0.87). Sixty-two of the patients were reexamined and rated by another neurologist. The interrater reliability coefficient (R) of the MSIS was 0.95, of the EDSS 0.91, and of the AI 0.94. Forty patients were examined twice by the first neurologist. The intrarater reliability coefficient was 0.97 for the MSIS, 0.95 for the EDSS, and 0.98 for the AI. The MSIS is easy to use and is robust to observer dissimilarities. It has a monomodal univariate distribution and has a better discriminatory power than the EDSS, especially in the EDSS range 6-9, while the interrater reliability of the MSIS is at least as good as that of the EDSS and the AI.

The implications of Epstein-Barr virus in multiple sclerosis--a review

The objective of this article is to bring together knowledge about Epstein-Barr virus (EBV) in relation to multiple sclerosis (MS) in order to evaluate its implications in this disease. All MS patients are EBV seropositive, but EBV is not normally detected in the brain. EBV can explain many of the epidemiological dogmas known in MS. In addition, other studies point towards the involvement of EBV in MS. Despite this, other co-actors seem also to be involved. We still need to know whether EBV may be an initiating factor in MS or whether it is a factor in the pathogenesis. Possible ways of EBV involvement are discussed: direct involvement, an autoimmune inducing factor or a transactivating factor. A current treatment study of MS patients with a specific herpes antiviral drug may add further information to the etiology and pathogenesis of MS.