A longitudinal study on antibodies to measles and rubella viruses in patients with multiple sclerosis. A preliminary report

Immune-mediated genesis of multiple sclerosis

Multiple sclerosis (MS) is widely acknowledged to be an autoimmune disease affecting the neuronal myelin structure of the CNS. Autoantigens recognized as the target of this autoimmune process are: myelin basal protein, anti-proteolipid protein, antimyelin-associated glycoprotein and antimyelin-based oligodendrocytic basic protein. Ample evidence supports the idea of a dysregulation of immunological tolerance towards self-antigens of neuronal myelin structure triggered by one or more viral or bacterial microbial agents in predisposed HLA gene subjects. Genetic predisposition to MS has been highlighted by numerous studies associating the disease to specific HLA haplotypes. Moreover, a wide range of evidence supports the fact that MS may be consequence of one or more viral or bacterial infections such as measles virus, EBV, HHV6, HZV, Chlamydia pneumoniae, Helicobacter Pylori, and other microbial agents. Microbiota elements also seems to have a role on the determinism of the disease as a pathogenic or protective factor. The autoimmune pathogenetic process could arise when a molecular mimicry between a foreign microbial antigen and an auto-antigen occurs in an HLA gene subject competent for that particular antigen. The antigen-presenting cells in this case would induce the activation of a specific Th clone causing a cross-reaction between a foreign antigen and an autoantigen resulting in an autoimmune response.

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A multifactorial ethiopathogenetic model based on immunomediation is a reliable hypothesis for multiple sclerosis.

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Evidence found in the scientific literature makes it possible to reconstruct this etiopathogenetic hypothesis for MS.

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HLA gene predisposition, correlation with infections, molecular mimicry and other immunological data are reported.

Expansion of antibody reactivity in the cerebrospinal fluid of multiple sclerosis patients - follow-up and clinical implications

BACKGROUND

An intrathecal polyspecific antibody response is a well known finding in multiple sclerosis. However, little is known about the evolution of intrathecal antibodies over time and their impact on the disease progress. Therefore, we focused in this study on the intrathecal polyspecific antibody response in multiple sclerosis.

METHODS

Here we present a follow-up study of 70 patients with multiple sclerosis over 1 to 106 months. Serum and cerebrospinal fluid sample pairs were obtained from 1 to 5 consecutive lumbar punctures. CSF cell count, the IgG index, local IgG synthesis, oligoclonal bands and the antibody index for measles, rubella or varicella zoster were calculated. Results were analysed with regard to clinical characteristics of the patients.

RESULTS

Once an intrathecal antibody response was established, it persisted. De novo antibody response against measles virus developed in 7% of the patients between the first and the second spinal tap. In two of seven patients where 5 consecutive CSF samples were available, the intrathecal antibody response expanded from one to three antigens. Furthermore, an intrathecal measles antibody production was associated with a rapid progression of the disease.

CONCLUSION

These data stress the importance of activated B cells for the disease process and the clinical outcome in multiple sclerosis.

Measles virus-specific IgM antibodies in sera from patients with chronic active hepatitis

The occurrence of measles virus-specific IgM antibodies in sera from patients with chronic active hepatitis not caused by Hepatitis B virus was examined by a specific enzyme-linked immunosorbent assay (ELISA). Using whole serum, specific IgM antibodies were detected in 12 of 23 sera from patients with hepatitis B surface antigen (HBsAg)-negative chronic active hepatitis. In nine of these sera the finding of specific IgM antibodies was verified by separation of IgM by density gradient centrifugation and examination of the fractions by ELISA. Most of the sera from the patients with measles virus-specific IgM antibodies had an elevated level of specific IgG antibodies compared to the level of IgG found in control sera. The significance of these findings in view of a possible persistent measles virus antigen production in patients with chronic active hepatitis is discussed.

Intrathecal synthesis of virus antibodies in multiple sclerosis patients

A follow-up study on the intrathecal synthesis of viral antibodies in multiple sclerosis patients was made on 28 patients over a period of about 2 years. Serial serum and cerebrospinal fluid specimens were assayed for antibodies against measles, rubella, parainfluenza type 2, respiratory syncytial, mumps, influenza A, influenza B, adeno, and herpes simplex viruses by employing a solid-phase enzyme immunoassay technique. All patients had local antibody synthesis against one or more of the antigens studied. Rubella and measles virus antibodies were found with the highest frequency and were synthesized at the highest rate. Simultaneous intrathecal antibody synthesis against the greater number of the viruses studied was associated with higher local immunoglobulin G synthesis. A good overall correspondence in the fluctuations of the different viral antibodies synthesized intrathecally was usually found. Sometimes the changes in intrathecal antibody levels correlated well with the changes in immunoglobulin G index and sometimes not. These fluctuations could not be correlated with the clinical course of the disease. The results of this study suggest that the viral antibodies studied are not relevant to the etiology or the pathogenesis of multiple sclerosis.

A study of measles virus and canine distemper virus antibodies, and of childhood infections in multiple sclerosis patients and controls

We investigated the levels of neutralizing antibodies to measles virus and canine distemper virus (CDV) in 72 multiple sclerosis patients (MS) and matched controls and also examined the frequency and age of onset of a number of childhood illnesses, including measles. The frequency of each childhood illness was not significantly different between cases and controls, but cases did report a later age at measles infection. Our data suggest that the risk of MS is increased by a factor of 1.9 if measles infection occurs between 5 and 9 years of age. A validity survey, based on a questionnaire to general practitioners, suggested substantial inaccuracy in the patients' reports of when they had measles, but the direction and degree of inaccuracy did not appear to be different between cases and controls. We also found higher titres of neutralizing antibodies in cases than controls to both measles virus and CDV, although the CDV difference was not statistically significant. In the light of a significant correlation between measles and CDV titres in both cases and controls, we used paired logistic regression to determine if the case-control difference in titres for each virus could be explained by a confounding effect on one by the other. The numbers were too small, however, to enable us to separate out any independent association of either virus with MS.

Characterization of measles virus-specific antibodies in sera from patients with chronic active hepatitis

Measles virus-specific antibodies in sera from patients with HBsAg-negative chronic active hepatitis and raised antibody titres against measles virus, have been examined by crossed immunoelectrophoresis. The immunoprecipitates were further analysed by SDS-polyacrylamide gel electrophoresis. Five measles virus-specific precipitation lines were demonstrated using measles virus-infected cells solubilized with Triton X-100. The three major precipitation lines were analysed by SDS-PAGE and contained the virus polypeptides: nucleoprotein, NP (MW approximately 60 000); haemoagglutinin, H (MW approximately 80 000) and fusion protein F1 (MW approximately 40 000). Considerably higher amounts of antibodies against these three virus polypeptides were demonstrated in the patient sera than in sera from healthy controls. By SDS-PAGE analysis of radiolabelled immune complexes adsorbed to Sepharose-protein A, antibodies against five measles virus polypeptides: NP, H, F1, P protein (MW approximately 70 000) and matrix protein, M (MW approximately 37 000) were demonstrated in the patient sera.

A longitudinal study of antibrain antibodies in multiple sclerosis

The presence of complement-fixing antibrain antibodies is a distinctive feature of multiple sclerosis (MS). In a longitudinal study of 35 MS patients antibrain antibody titres in serum were followed for up to 5 years; in 18 of them also CSF titres were determined. No consistent correlations between antibrain antibody titres and clinical events were found. Thus, MS relapses are not caused by a general increase in antibrain antibody titres, and conversely the relapses did not cause a boosting of antibrain antibodies. Significant variations in the local plaque environment are, however, not ruled out by the present results.

The significance of abnormal immune responses in patients with multiple sclerosis

Early diagnosis of multiple sclerosis (MS) may be assisted by tests for the abnormal immune responses of the central nervous system (CNS) including oligoclonal IgG bands in the cerebrospinal fluid (CSF), increased CNS IgG synthesis, increased CNS antibody synthesis against multiple viruses and increased numbers of enlarged lymphoid cells in the CSF. Alterations in immunological responses are important in the pathogenesis of MS. Further studies are needed, however, to identify the antigen(s) and/or antibodies responsible for oligoclonal IgG in the CSF of MS patients. Also, the cause(s) for the other immunological abnormalities with diagnostic importance need to be identified. The increased synthesis of antibodies against multiple unrelated viruses suggests generalized alteration in the immune regulatory system. The etiology of MS might be multifactorial involving abnormal immunological responses, possibly precipitated by infectious agents acquired during childhood by genetically susceptible individuals. The immunological responses including alterations in myelin basic protein concentration, antimyelin antibody and immune complex activities in CSF, and in vitro stimulation, suppression and migration inhibition of blood lymphocytes appear to correlate with stage of MS and severity of CNS damage. Some of the tests may become useful in estimating the prognosis of the disease. Longitudinal studies are needed to clarify the sensitivity of the diagnostic and prognostic immunological tests and etiological significance of these abnormalities in MS.

Measles antibodies, kappa-lambda light chain distribution and immunoglobulins in serum, cerebrospinal fluid and brain of a patient affected with multiple sclerosis

The serum, cerebrospinal (CSF) and brain of a patient (NAG) affected with multiple sclerosis (MS) were examined for measles antibodies with CF and HI techniques, and the kappa-lambda light chain ratios of all samples available were evaluated, kappa-lambda populations of the matched serum, CSF and brain specimens were all lambda-predominant and in agreement with each other; the light chain distribution f the brain specimens confirmed previous findings [3]. Only the serum immunoglobulins showed significant measles antibody titers, but slightly increased measles antibody titers were also observed in ventricular plaques. The amount of immunoglobulin G (IgG) synthesized per day by the central nervous system (CNS) was estimated. The IgG synthesis in CNS NAG (11.6 mg/day) was above the upper limit of the normal range (3.3 mg/day), but apparently there was no positive correlation between the intracerebral IgG synthesis and specific anti-measles IgG.

Abnormal regulation of in vitro IgG production in multiple sclerosis

A pokeweed mitogen-stimulated IgG synthesis assay was used to evaluate T suppressor cell function in peripheral blood lymphocytes (PBL) obtained from multiple sclerosis (MS) patients. Autochthonous cultures of fractionated and recombined MS B and T cells exhibited less suppression of IgG synthesis than similar cultures of PBL from control subjects. No difference occurred in the levels of suppression among MS patients grouped according to disease states. When allogenic cultures of MS B and normal T cells or normal B and MS T cells were compared to autochthonous cultures of control cells, no differences were observed. The results suggest that the lower levels of suppression observed in autologous MS cell cultures are not a result of T suppressor cell dysfunction alone.

Measles antibodies and kappa-lambda light chain distribution in immunoglobulins of patients affected with multiple sclerosis

The presence of measles antibodies in serum immunoglobulin G fractions from seven patients affected with multiple sclerosis was investigated with HI technic. The kappa-lambda light chain ratios of all samples under investigation were evaluated. Three multiple sclerosis patients, who displayed either fractionation or a tendency towards fractionation in their serum, had slightly elevated measles antibody titers associated to increased kappa/lambda ratios.

Multiple sclerosis: oligoclonal IgG, kappa-lambda light chain distribution and measles antibodies in brain extracts

The presence of measles antibodies in white and grey brain material and in 8 demyelination plaques from 6 patients affected with multiple sclerosis was investigated with the hemagglutination inhibition (HI) and complement fixation (CF) techniques. White and grey matter of 5 controls were run in parallel. No measles antibodies could be detected, except for one plaque, where the answer could be considered as doubtful. The immunoglobulin G (IgG) content and the kappa/lambda light chain ratios of all the samples were evaluated. No unique monoclonal immunoglobulin population could be detected, but kappa or lambda predominant oligoclonal populations appeared in controls as well as in MS IgG.

Solid-phase radioimmunoassay detection of rubella virus IgG antibody in serum and CSF of patients with multiple sclerosis

Low levels of rubella virus IgG antibody have been detected in cerebrospinal fluid (CSF) specimens of multiple sclerosis (MS) patients by a solid-phase radioimmunoassay (RIA) previously developed for testing of clinical serum samples. Paired serum and CSF specimens of 36 MS patients and 12 control patients were analyzed. Of those MS patients which had negative CSF titers in the rubella hemagglutination inhibition (HAI) test, 90% (11/12) were found to have rubella IgG antibody by the RIA method. In specimens found to contain rubella IgG antibodies by both methods, the RIA test was approximately 15 times more sensitive than the rubella HAI test. The results presented suggest that a considerable portion of MS patients have significantly reduced serum/CSF rubella IgG antibody ratios, indicating that there is a local production of rubella antibodies in the central nervous system of these patients.