The immune response against myelin basic protein in two strains of rat with different genetic capacity to develop experimental allergic encephalomyelitis.

After challenge with guiena pig basic protein (GPBP) Lewis (Le) rats, which are homozygous for the immune response experimental allergic encephalomyelitis (Ir-EAE) gene, developed positive delayed skin tests against GPBP and the 43 residue encephalitogenic fragment (EF); in addition, Le rat lymph node cells (LNC) were stimulated and produced migration inhibitory factor (MIF) when incubated in vitro with these antigens. In contrast Brown Norway (BN) rats, which lack the Ir-EAE gene, did not develop delayed skin tests to EF and their LNC were not stimulated and did not produce MIF when incubated in vitro with EF. These observations indicate that the Ir-EAE gene controls a T-cell response against the EF. Le rats produced measurable anti-BP antibody by radioimmunoassay after primary challenge. Although no antibody was detectable in BN rats by radioimmunoassay, radioimmunoelectrophoresis indicated that a small amount of antibody was formed after primary immunization. After boosting intraperitoneally, both strains of rat exhibited a rise in anti-BP antibody; which was greater in Le rats. In both strains of rat the anti-BP antibody reacted with a portion of the molecule other than the EF. Since EF primarily evokes a T cell response, it is suggested that the EF portion of the BP molecule may contain a helper determinant in antibody production.

Immune response of Lewis rats to peptide C1 (residues 68-88) of guinea pig and rat myelin basic proteins.

Peptide C1 (residues 68-88) from GP and rat BP differ by a single amino acid interchange at residue 79. This residue is serine in GP C1 and threonine in rat C1. GP C1 was encephalitogenic in Le rats at doses as low as 15 ng. Rat C1 was encephalitogenic at doses of 1,500 ng or greater. LNC from rats challenged with 25 X 10(-4) micronmol of GP C1 and 250 X 10(-4) micronmol of rat C1 showed a proliferative response in vitro to both peptides, but in each instance the magnitude of the response was greater to the GP peptide. GP C1 also induced higher levels of circulating antibodies at 25 X 10(-4) micronmol, but the specificity of antibodies produced by the two peptides was the same. These results have been interpreted as indicating that the presence of serine at position 79 in GP C1 results in the stimulation of greater numbers of T cells involved in (a) the induction of EAE, (b) the in vitro proliferative response and (c) helper function in antibody production.

A myelin basic protein peptide is recognized by cytotoxic T cells in the context of four HLA-DR types associated with multiple sclerosis.

We have examined previously the peptide specificity of the T cell response to myelin basic protein (MBP) in patients with multiple sclerosis (MS) and healthy controls, and demonstrated that an epitope spanning amino acids 87-106 was frequently recognized. Because this region is encephalitogenic in some experimental animals, it has been postulated that the response to the epitope may have relevance to MS. In this study, the fine specificity of this response is studied using four well-characterized, monospecific T cell lines from three MS patients and an identical twin of a patient. Each of the lines recognized a peptide with the same core sequence, amino acids 89-99, although the responses were affected to various degrees by truncations at the COOH- or NH2 terminal ends of the 87-106 epitope. Importantly, the epitope was recognized in conjunction with four different HLA-DR molecules. Also, the T cell receptor beta chain usage was heterogeneous, and each line expressed a different VDJ sequence. The four HLA-DR molecules restricting the response to this epitope have been shown to be overrepresented in MS populations in various geographic areas, suggesting that the response to this region of the MBP molecule may be relevant to the pathogenesis of MS. These findings may have important implications in designing therapeutic strategies for the disease.

Experimental allergic encephalomyelitis in the rat: response to encephalitogenic proteins and peptides.

Lewis rats were used to determine the encephalitogenic activity of myelin basic protein of different species and of 45-residue fragments of basic protein. Basic protein from guinea pigs was more active than that from rats, and the fragments from the two species showed the same order of activity. Bovine basic protein was the least active of the intact proteins, and the respective fragment was inactive. Studies of serum-binding capacity did not support the hypothesis that blocking antibody played a role in this biological variation, whereas consideration of the amino acid sequences of the three fragments suggested that differences in primary structure, operating either at the sensitization or the effector phase of the immune response, could account for the variation.

Immunoglobulin metabolism in ataxia telangiectasia.

Immunoglobulin metabolism has been studied in five patients with ataxia telangiectasia and in control subjects. Serum IgG levels were normal, increased, or decreased, reflecting normal, increased, or decreased synthetic rates, respectively. Serum IgM concentration was normal in three cases and slightly elevated in two cases. IgM turnover studies in the three cases with normal serum IgM levels showed normal IgM synthetic and catabolic rates. None of the five patients with ataxia telangiectasia had detectable serum IgA, and the maximum IgA synthetic rates possible for these patients were 0.3-10% of the normal mean synthetic rate (24 +/- 15 mg/kg per day) of 12 control individuals. Three of the patients had normal IgA fractional catabolic rates: 22% of the intravascular pool per day vs. 25 +/- 4% in controls. In two patients, fractional catabolic rates 4 and 20 times normal were found. In these cases, metabolic turnover, in vitro precipitation, radioimmunoelectrophoresis, and (or) the C'la fixation and transfer test provided evidence for the presence of a circulating antibody directed against IgA causing immune elimination of the molecule. These studies suggest that therapy with exogenous IgA may not be possible in some patients with ataxia telangiectasia or in other subjects with dysgammaglobulinemia.

Detection of B cell antigens in multiple sclerosis. Use of serum from multiparous women.

Sera from two multiparous wives of patients with multiple sclerosis (MS) were used to detect B cell antigens in other patients. With serum X, 11 of 16 patients were positive as compared with ten of 16 controls (.05 less than P less than .1). With serum Y, a positive response was found in 11 of 16 patients and two of 23 controls (P less than .0005). Ten of the 11 patients who were positive with serum Y were also HLA-Dw2, which suggests that the B cell antigen detected by this serum is linked to Dw2. Three of four Dw2-positive controls were negative with serum Y, which raises two alternative hypothetical possibilities concerning the B cell antigen. These findings indicate that serum from multiparous wives may be an important tool in the investigation of the genetic components associated with MS.

Oligoclonal bands in CSF: twins with MS.

Oligoclonal bands ( OCBs ) were examined in CSF from 23 normal controls, 8 cases of inflammatory neurologic diseases, 24 cases of noninflammatory neurologic diseases, 27 sporadic cases of MS, and the 29 MS twin pairs, by isoelectric focusing followed by silver staining or western transblotting and immunoperoxidase staining. These methods are sensitive enough to detect as little as 25 ng of IgG. OCBs were detected in the CSF of 34 of 35 twins with clinical evidence of MS and in the CSF of 12 of 17 clinically normal twins. In some of these normal twins, the presence of OCBs in CSF antedated clinical manifestations of the disease.

Sequence comparisons of HTLV-I from HAM/TSP patients and their asymptomatic spouses.

We amplified and sequenced portions of the human T-lymphotropic virus type I (HTLV-I) (U3), pol, env, and pX provirus regions (1212 bp per person) from peripheral blood lymphocytes (PBL) of two married couples (case 1 and case 2). Both husbands are patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and the wives are asymptomatic HTLV-I carriers. We selected these regions because the LTR and env regions of murine retrovirus models have been involved in determining tissue tropism. In addition, the predominant immunogenic epitope for HTLV-I-specific cytotoxic T cells obtained from circulating PBL of HAM/TSP patients was localized in the HTLV-I pX region. Our aim was to examine variations in these HTLV-I regions between affected and asymptomatic spouses. In the HTLV-I regions studied, we detected no sequence variation between each couple. These data do not favor the hypothesis that neurotropic mutants of HTLV-I are involved in the pathogenesis of HAM/TSP.

Subacute sclerosing panencephalitis after passive immunization and natural measles infection: role of antibody in persistence of measles virus.

Subacute sclerosing panencephalitis (SSPE) developed in a patient in whom natural measles infection was anteceded by immunization with measles immune serum globulin (ISG). This observation prompted experimental studies of the role of antibody in viral persistence. When Balb/c mice were infected with the hamster neurotropic measles virus, acute encephalopathy was fatal in 80% of the animals. When measles antibody was administered 3 days after virus inoculation, the acute disease was abolished and subacute encephalitis had a 30% mortality. The subacute disease was characterized by the presence of neuronal viral antigen, meningitis, and encephalitis. Induction of viral persistence was therefore a consequence of antibody transfer during viral infection. Caution is advised in human prophylaxis with immune globulin.

Gamma-interferon induction in patients with chronic progressive MS.

Although gamma interferon (gamma-IFN) may be involved in the pathogenesis of exacerbations of multiple sclerosis (MS), whether it plays a role in chronic progressive MS is not known. To investigate this, we retrospectively analyzed serum samples from nine chronic progressive MS patients who were treated with monthly intravenous infusions of the interferon inducer polyinosinic acid polycytidylic acid polylysine in carboxymethylcellulose (poly ICLC). Using a bioassay we found that the mean peak total interferon level was 177 U/ml 12 hours after infusion, and using a radioimmunoassay we found that the mean peak gamma-IFN level was 15.9 U/ml 12 hours after infusion, so that gamma-IFN made up approximately 10% of the total. Greater gamma-IFN induction did not correlate with clinical worsening; induced gamma-IFN levels were not higher in two patients who worsened on treatment, and the highest levels were found in a patient who remained stable. Either chronic progressive MS is not sensitive to gamma-IFN or the effects of gamma-IFN are masked by other mediators induced by poly ICLC.

Quantitation of IgG, IgA and IgM in the CSF by radioimmunoassay.

A radioimmunoassay (RIA) for quantitating IgG, IgA and IgM in unconcentrated CSF has been developed. The amounts and percentages of these immunoglobulins in CSF from 31 normal individuals were determined. Using these values as normal, CSF from patients with syphilis, encephalitis, subacute sclerosing panencephalitis (SSPE), and multiple sclerosis (MS) was studied. Abnormalities were detected, indicating the potential relevance of more extensive study of the CSF immunoglobulins. CSF from patients with myotonic dystrophy and myasthenia gravis was normal. RIA was compared with rocket electroimmunodiffusion (EID) for the quantitation of IgG. Although RIA consistently gave lower absolute values, both assays reliably detect elevated IgG in CSF. However, an advantage of RIA is its capacity to quantitate IgA and IgM.

Increased CSF IgM in multiple sclerosis.

CSF IgM levels have been measured by radioimmunoassay in 56 patients with MS, 62 patients with other neurologic diseases, and 31 normal controls. Forty-eight percent of the patients with MS had a raised CSF IgM level compared with 5 percent of the patients with other diseases. The IgM level did not correlate with the IgG level. Forty percent of the MS patients with normal IgG levels had high IgM levels. No relationship was found between the CSF IgM level and length or severity of the MS, relapses, or steroid therapy. Attempts to identify the IgM as being anti-measles were unsuccessful.

Measles virus polypeptide-specific antibody profile in multiple sclerosis.

Elevated antibody (Ab) titers to measles virus (MV) is a frequent finding in MS. Although MV-Abs are synthesized intrathecally, it is not known whether this is due to polyclonal activation of B cells recruited from the blood, recognition of MV antigens within the CNS, or cross-reactivity with myelin antigens. This study examined these possibilities using purified MV polypeptides. We examined Ab reactivity to each polypeptide in serum and CSF from 21 MS patients, 5 with subacute sclerosing panencephalitis (SSPE), and 11 patients with other neurologic diseases (OND), and serum from 5 patients with acute MV infection and 11 normal controls. The serum of all subjects tested contained reactivity with MV and the 5 polypeptides. Of 21 MS patients, 20 had CSF reactivity with MV compared with 3/11 ONDs and 5/5 SSPE patients. Intrathecal MV-Ab synthesis was present in 11/21 MS patients, 5/5 SSPE, and in none of the ONDs. Nine of 21 MS patients had intrathecal synthesis of Ab to 2 MV polypeptides. Serum and CSF reactivity in MS patients was skewed towards the F polypeptide. The results are consistent with the concept of polyclonal B cell activation within the CNS, but the heightened response to F could also reflect cross-reactivity with a relevant antigen in MS.

Preliminary trial of poly ICLC in chronic progressive multiple sclerosis.

Eighteen patients with chronic progressive multiple sclerosis (MS) were treated in an open preliminary trial of the interferon inducer and immune modulator, poly ICLC. All patients produced substantial interferon levels and experienced acute side effects, including fever and transient worsening of neurologic symptoms. Of nine patients with rapid neurologic deterioration at the time of entry into the study, only three had disease progression during treatment. We conclude that poly ICLC can be administered safely to MS patients, and that a controlled trial will be necessary to determine efficacy.

Changes in the amount of diseased white matter over time in patients with relapsing-remitting multiple sclerosis.

MRI is a sensitive technique for assessing disease activity in MS. Diseased white matter (WM) can be identified on T2-weighted images, and active disease is reflected by abnormalities in the blood-brain barrier (BBB) shown on T1-weighted images after administration of paramagnetic contrast agents. Active disease may be demonstrated by contrast-enhanced MRI in patients with early, mild relapsing-remitting (RR) MS even during periods of clinical stability, which indicates that MS is an active process even during the early phase of the illness. To examine the amount of abnormal WM at frequent intervals over time, we studied seven mildly affected RRMS patients, all of whom had frequent contrast-enhancing lesions. These RRMS patients were imaged monthly for 26 to 36 months at 1.5 tesla; the area of abnormal increased WM signal was calculated by image-processing software that utilizes both the T2- and T1-weighted images. All patients showed fluctuations over time in amount of abnormal WM signal, which reflected factors such as the amount of BBB breakdown (measured by number or area of enhancing lesions) and measurement error. All seven RRMS patients, however, showed an overall increase in abnormal WM. Because of the fluctuations between individual measurements, the increase was most accurately reflected when the mean of the first 6 months' measurements was compared with the mean of the final 6 months' measurements, or when a linear regression model was applied.(ABSTRACT TRUNCATED AT 250 WORDS)

Demyelinating disease after neurologically complicated primary Epstein-Barr virus infection.

This report describes five patients who, following a neurologically complicated primary Epstein-Barr virus infection, developed progressive or relapsing neurologic deficits. The sequelae in four patients followed 4 to 12 years led to the diagnosis of multiple sclerosis (MS). The fifth patient presented with acute disseminated sclerosis and exhibits diffuse neurologic deficits that have persisted for 2 years. We suggest that the diagnosis of an unexplained acute neurologic or psychiatric syndrome should raise the question of a primary EBV etiology. A precisely timed serologic and hematologic study of the blood is imperative to capture the essential evidence. The data presented represent a clinical association between a neurologically complicated primary EBV infection and both chronic and acute demyelinating disease. The evidence does not justify a conclusion that EBV virus causes MS.

Morphologic and immunologic studies in experimental autoimmune myasthenia gravis and myasthenia gravis.

An indirect immunoperoxidase technique was used to study by light microscopy the binding of serum from experimental autoimmune myasthenia gravis (EAMG) rabbits to junctionally and extrajunctionally located acetylcholine receptors (AChRs) in human and rat muscles. Binding was restricted to junctional AChR. Alpha bungarotoxin (a-BGT) partially blocked the binding of EAMG serum, while myasthenia gravis serum, carbamylcholine, decamethonium, and tubocurarine did not. A radioimmunoassay showed significant binding of antibodies in EAMG sera to 125l AChR. This binding was not inhibited by a-BGT, nor by carbamylcholine, decamethonium, or tubocurarine. Sera from 10 myasthenia gravis patients did not contain antibodies binding to the 125l AChR. We suggest that EAMG in rabbits induced by Torpedo AChR differs serologically from myasthenia gravis in patients, probably owing to antigenic differences between Torpedo and human AChR, and that antigenic differences also exist between junctional and extrajunctional receptors.

A multivalent antibody radioimmunoassay (MARIA) for screening specific antibody secretion by lymphocyte hybridoma cultures.

A new radioimmunoassay which is suitable for screening lymphocyte hybridoma cultures for monoclonal antibody production is described. Solid-phase antigen is first incubated with the sample, and secondly with soluble 125I-labeled antigen. When the sample contains multivalent specific antibody, the labeled antigen will be bound to the solid-phase antigen. Because no anti-immunoglobulin reagent is used as a second reagent, this type of radioimmunoassay offers several advantages, in particular for the production of monoclonal anti-idiotypic antibodies.

Leukocyte surface antigens in patients with multiple sclerosis.

Lymphocyte phenotypes have been measured in 20 normal females, 19 normal males, 3 females with acute exacerbations of MS and 21 females and 17 males with chronic progressive MS. Using a FACS IV, lymphocytes were gated by light scattering properties, and fluorescence was analyzed using a log amplifier. No abnormalities were found in the 3 females with acute exacerbations. In male patients the percentage of OKT8 was significantly reduced, the percentage of OKT4 was significantly increased, and the ratio of OKT4/T8 was increased. In females with chronic progressive disease the percentage of OKT8 was not statistically altered, but the percentage of OKT4 and the OKT4/T8 ratio were elevated. Interpretation of these findings requires more extensive study in control populations.

Genetic control of antibody production to myelin basic protein in mice.

Experimental allergic encephalomyelitis (EAE) is a disease produced by inoculation of myelin basic protein (BP) into susceptible animals. Data in this report link the production of anti-BP antibody to the murine H-2 histocompatibility background. H-2k and H-2a animals produce high levels of anti-BP antibodies as measuring during both primary and secondary immune responses. Strains with H-2b,d,p,q,s haplotypes are poor responders after primary immunization; however some H-2s and H-2d animals showed an increase in antibody after boosting. The use of M. tuberculosis instead of M. butyricum resulted in greater antibody production in H-2d strains. The response observed in 4 congenic pairs of mice support the association between antibody formation and the H-2 complex. Experiments with recombination inbred strains indicate that responsible genes reside in the I-A region of the H-2 complex.