CSF immune variables in patients with narcolepsy

Cerebrospinal fluid (CSF) and serum from 15 patients with narcolepsy were examined regarding presence of oligoclonal bands on isoelectric focusing, IgG index elevation as indicator of intrathecal IgG production and CSF/serum albumin ratios. Two of 15 patients (13%) showed oligoclonal IgG bands in CSF, one of whom had increased IgG index. Slight disturbance of blood-brain-barrier function as reflected by elevated CSF/serum albumin ratios was present in 4 other patients. The frequency of oligoclonal IgG bands in CSF from patients with narcolepsy is within the range of what is found in other neurological, non-inflammatory diseases. These findings do not support the hypothesis of an immune-mediated pathogenesis of narcolepsy.     

Blood-cerebrospinal fluid barrier permeability to serum IgG subfractions and measurement of intrathecal IgG synthesis

CSF/serum gradients of IgG subfractions separated by isoelectric focusing (IF) have been measured by high resolving laser densitometry. In patients with normal blood-CSF barrier permeability (N.25) and with barrier damage due to acute idiopathic polyneuropathy (N.15) and to medullary compression (N.17), the CSF/serum gradients of IgG subfractions were negatively correlated with their pI. This electrostatic selectivity appeared to be reverted in barrier damage due to acute meningoencephalitis (N.15). In a series of multiple sclerosis patients (N.31), the CSF/serum gradients of IgG subfractions lacking CSF oligoclonal bands have been used to assess the overall barrier permeability to serum IgG. All intra-BCB synthesized IgG subfractions could be measured by densitometry, whereas with other quantitative formulae, 23-26% of the results were false negatives; the total intrathecal IgG amount ranged from 0.01 to 11 mg/dl. The most frequent and prominent fractions appeared to be cathodic. Electrostatic and steric barrier selectivity must be taken into account when the amount of intrathecal IgG synthesis has to be measured.     

Intrathecal production of oligoclonal IgM and IgG in CNS sarcoidosis

A longitudinal study of multiple paired CSF and serum specimens from a patient with CNS sarcoidosis revealed high CSF IgM and IgG indices as well as oligoclonal IgM and IgG bands in CSF reflecting intrathecal IgM and IgG production. The antibody specificity of intrathecally-produced IgM and IgG remained undefined despite analysis for antibodies against mycobacterium tuberculosis and Kveim suspension. Steroid treatment induced rapid and complete clinical remission, and also decrease of CSF IgM and IgG antibodies, while oligoclonal IgM and IgG persisted in CSF. Repeated determinations of these CSF variables together with cell count and CSF/serum albumin ratio as a variable of blood-brain barrier function, might be useful in assessing effect of therapy in CNS sarcoidosis.     

Cerebrospinal fluid in the diagnosis of multiple sclerosis: a consensus report.

The Committee of the European Concerted Action for Multiple Sclerosis (Charcot Foundation) organised five workshops to discuss CSF analytical standards in the diagnosis of multiple sclerosis. This consensus report from 12 European countries summarises the results of those workshops. It is hoped that neurologists will confer with their colleagues in clinical chemistry to arrange the best possible local practice. The most sensitive method for the detection of oligoclonal immunoglobulin bands is isoelectric focusing. The same amounts of IgG in parallel CSF and serum samples are used and oligoclonal bands are revealed with IgG specific antibody staining. All laboratories performing isoelectric focusing should check their technique at least annually using "blind" standards for the five different CSF and serum patterns. Quantitative measurements of IgG production in the CNS are less sensitive than isoelectric focusing. The preferred method for detection of blood-CSF barrier dysfunction is the albumin quotient. The CSF albumin or total protein concentrations are less satisfactory. These results must be interpreted with reference to the age of the patient and the local method of determination. Cells should be counted. The normal value is no more than 4 cells/microliters. Among evolving optional tests, measurement of the combined local synthesis of antibodies against measles, rubella, and/or varicella zoster could represent a significant advance if it offers higher specificity (not sensitivity) for identifying chronic rather than acute inflammation. Other tests that may have useful correlations with clinical indices include those for oligoclonal free light chains, IgM, IgA, or myelin basic protein concentrations.     

The cerebrospinal fluid in multiple sclerosis. Quantitative assessment of intrathecal immunoglobulin synthesis by empirical formulae

Intrathecal synthesis of IgG occurs in more than 90% of patients with clinically definite multiple sclerosis. The prevalence and significance of intrathecal synthesis of IgA and IgM are, however, less thoroughly characterized. We estimated intrathecal synthesis of IgG, IgA and IgM with various empirical formulae. The concentrations of albumin, IgG, IgA and IgM and the presence of IgG oligoclonal bands were determined in CSF and serum from 350 patients, including 97 with clinically definite multiple sclerosis. Intrathecal synthesis of IgG oligoclonal bands was detected in 95% of patients with multiple sclerosis (95% confidence interval 88–98%). The IgG-index, an extended IgG-index, and a hyperbolic IgG formula performed approximately equally in identifying patients with MS, but they were all inferior to the detection of IgG oligoclonal bands. In quantitative measurements, the extended immunoglobulin indices appeared to perform well; studies comparing the extended IgA- and IgM-indices to qualitative analyses (electrophoresis or isoelectric focusing) are, however, needed to confirm this. Detection of intrathecal synthesis of IgA of IgM was of little value in the diagnosis of multiple sclerosis.     

Progressive myoclonus epilepsy is not accompanied by humoral immune response within the central nervous system

CSF and serum from five patients with progressive myoclonus epilepsy taken on two occasions with about one month's interval were examined for intrathecal humoral immune response. The CSF IgG and IgA index values were normal, and no oligoclonal bands were detectable by agarose electrophoresis or polyacrylamide isoelectric focusing (IEF). Immunofixation of IEF separated IgG with four different viruses as possible antigens, and autoradiography did not reveal any intrathecal antibody production. In contradiction to previous reports, no evidence was obtained for a local humoral immune response in progressive myoclonus epilepsy.     

IgG paraproteinemias: a comparative CSF and serum study

In 10 neurologic patients routine isoelectric focusing of CSF and serum revealed monoclonal IgG paraproteinemia (3 multiple myelomas and 7 benign monoclonal gammopathies). Quantitative protein study showed blood-brain barrier damage in 7 out of 10 patients; 2 patients had intrathecal synthesis of IgG measurable by Reiber's formula. Each case showed identical monoclonal IgG pattern in CSF and serum at isoelectric focusing and immunofixation. We suppose that monoclonal IgG detectable in the CSF usually derive from the serum across the intact or damaged barrier. The occurrence of quantifiable intrathecally synthesized IgG in 2 patients, both with skeletal lesions close to the subarachnoid spaces, and the identical patterns of IgG in CSF and serum suggest that tumoral plasma cells secrete monoclonal IgG into blood and CSF from the bone location.     

GAD65 IgG autoantibodies in stiff person syndrome: clonality, avidity and persistence

Background and purpose:  Persistent intrathecal production of IgG autoantibodies against glutamic acid decarboxylase 65 (GAD65 IgG) and oligoclonal IgG of undetermined specificity has been reported in stiff person syndrome (SPS).
Methods:  To chart the avidity and clonal patterns of GAD65 IgG, we performed scatchard plot of binding characteristics and isoelectric focusing-immunoblot of cerebrospinal fluid (CSF) and serum from five SPS patients.
Results:  Oligoclonal GAD65 IgG bands, predominantly restricted to the IgG1 subclass, were detected in CSF and serum in all patients. The distribution of GAD65-specific IgG bands in serum and CSF revealed intrathecal synthesis of oligoclonal GAD65 IgG in all five patients, whilst radioimmunoassay demonstrated intrathecal synthesis of GAD65 IgG in four. The binding avidity of GAD65 IgG from CSF was more than 10 times higher than in serum in two of the patients but did not differ substantially in the remaining three. These differences were not related to symptom severity. The pattern of oligoclonal GAD65 IgG bands in CSF and serum in three patients examined remained unchanged for up to 7 years after symptom debut.
Conclusion:  This study confirms the persistent systemic and intrathecal production of GAD65-specific IgG in SPS, and further shows that this immune response is oligoclonal and mediated by a stable population of affinity maturated B cell clones.     

Qualitative evidence of anti-Yo-specific intrathecal antibody synthesis in patients with paraneoplastic cerebellar degeneration

We investigated the presence of anti-Yo-specific oligoclonal antibody bands in cerebrospinal fluid (CSF) and serum samples of 9 patients with anti-Yo syndrome and 11 controls. Isoelectric focusing combined with affinity blotting, revealed anti-Yo-specific intrathecal antibody synthesis in all patients with anti-Yo syndrome: Four patients had positive anti-Yo-specific oligoclonal IgG bands in CSF which were not demonstrable in their sera; five CSF/serum pairs showed additional, more intensive, oligoclonal bands in CSF compared to the corresponding serum. Interestingly, four patients with absence of oligoclonal bands of total IgG in CSF revealed positive anti-Yo-specific oligoclonal bands in the same sample. This speaks for a higher sensitivity of detection of oligoclonal bands using an affinity blot loaded with Yo-specific antigen compared to an affinity blot coated with anti-human IgG used for the detection of oligoclonal bands of total IgG. In conclusion, the presence of anti-Yo-specific oligoclonal IgG bands in CSF which were absent, or less strong, in patients sera provides qualitative evidence of anti-Yo-specific IgG synthesis by intrathecal B-cell clones. These results could be of interest in detection of intrathecal-specific IgG synthesis in nervous system infectious diseases provided that the target antigen is known.     

Immunoglobulin abnormalities in the cerebrospinal fluid during bacterial meningitis

11 patients with bacterial meningitis, examined during the course of the disease for immunoglobulin (Ig) abnormalities in the cerebrospinal fluid (CSF), all had an increased CSF IgM index equal to (CSF/serum IgM):(CSF/serum albumin), indicating intrathecal IgM production. Seven patients had a slightly increased CSF IgG index, and 7 a slightly increased IgA index. Six of the 11 patients had an increased IgM index in the presence of normal indices for IgG and IgA. Follow-up revealed the return of these values to normal. Four patients had identical oligoclonal IgG bands in the CSF and serum, probably representing a systemic immune response, but in only one case were oligoclonal bands suggestive of intrathecal IgG production found. No oligoclonal IgA response was demonstrable in the 4 patients examined. Antigen-immunofixation or antigen-absorption studies revealed evidence of a specific, intrathecal IgG antibody response in only 2 patients, while a search for IgG antibodies against aetiologically unrelated bacterial and viral antigens was negative. With the exception of IgM production, therefore, a humoral intrathecal immune response is less common in bacterial than in aseptic meningitis.     

Oligoclonal banding of IgG in CSF,blood-brain barrier function,and MRI findings in patients with sarcoidosis,systemic lupus erythematosus,and Beh?et's disease involving the nervous system.

A retrospective study of CSF and serum analysis from a total of 43 patients with sarcoidosis, 20 with systemic lupus erythematosus, and 12 with Behçet's disease with neurological involvement found local synthesis of oligoclonal IgG using isoelectric focusing and immunoblotting in 51%, 25%, and 8% respectively at some stage in their disease. Blood-brain barrier breakdown, when assessed with an albumin ratio found 47% of patients with sarcoidosis, 30% of those with systemic lupus erythematosus, and 42% of patients with Behçet's disease exhibiting abnormal barrier function at some time. Serial CSF analysis showed that clinical relapses were associated with worsening barrier function and in some patients the development of local oligoclonal IgG synthesis; conversely steroid treatment led to a statistically significant improvement in barrier function, and in two patients a loss of oligoclonal IgG bands. A higher proportion of patients had MRI abnormalities than oligoclonal IgG or blood-brain barrier breakdown, MRI being abnormal in 16 of 19 patients with sarcoidosis, three of four patients with systemic lupus erythematosus, and seven of nine patients with Behçet's disease, although this may have been due to temporal factors. In the differential diagnosis of chronic neurological disorders, locally synthesised oligoclonal IgG cannot distinguish between diseases, but the loss of bands seen in two patients contrasts with what is seen in multiple sclerosis, and thus may be a useful diagnostic clue.     

Multiple sclerosis in Brazil. Analysis of cerebrospinal fluid by standard methods

The demonstration of intrathecal IgG synthesis has been used as an important laboratory parameter to support the diagnosis of multiple sclerosis (MS). The Committee for European Concerted Action for Multiple Sclerosis has recommended a protocol for the assessment of intrathecal IgG synthesis. We applied this methodology to determine the cerebrospinal (CSF) profile of 128 Brazilian patients with MS. We detected hypercytosis lower than 35 cells/mm3 in 97%, protein lower than 80 mg/dl in 99%, normal blood-CSF barrier function in 76%, increased IgG local production around 53% and oligoclonal IgG bands by isoelectric focusing in 85% of the definite MS patients. The diagnostic accuracy of the quantitative analysis was lower than the qualitative. The detection of oligoclonal bands was especially important in the cases of normal quantitative assays of IgG. In addition, we found a lower frequency of inflammatory reaction in CSF in our MS cases, in comparison to some European studies.     

Intrathecal IgG synthesis in multiple sclerosis and other neurological diseases: A comparative evaluation by IgG-index and isoelectric focusing

Summary Intrathecal IgG synthesis has been investigated by determining the IgG index and by isoelectric focusing in 30 cases of definite multiple sclerosis, in 15 cases of probable multiple sclerosis and in 128 patients affected by other neurological diseases. The blood-brain barrier function was evaluated at the same time by serum albumin/CSF albumin quotient and isoelectric focusing. The IgG index was found elevated in 73.3% of definite multiple sclerosis patients, while oligoclonal IgG bands occurred in 90%. In the other neurological diseases the IgG index was abnormally increased in 35.1% but IgG bands were present only in cerebrospinal fluid (CSF) in 1.5% and both in the CSF and serum in 7% of patients.The high capacity of isoelectric focusing to detect IgG oligoclonal bands in the CSF is pointed out as an extremely useful diagnostic tool in multiple sclerosis.

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Zusammenfassung Das Vorhandensein von IgG-Synthese im Nervensystem wurde mittels IgG-Index-Determination und mittels Isoelektrischer Fokalisation untersucht, und zwar bei 30 Fällen mit eindeutig diagnostizierter Multipler Sklerose, bei 15 Fällen, in denen Multiple Sklerose wahrscheinlich ist, und bei 128 Patienten, die andere neurologische Erkrankungen aufwiesen. Gleichzeitig wurde die Blut-Hirn-Schrankenfunktion untersucht mittels des Albuminserums des CSF-Albumin-Quotienten und Isoelektrischer Fokalisation. Es zeigte sich, daß der IgG-Index bei 73,3% der eindeutig diagnostizierten Multiple-Sklerose-Patienten erhöht ist, während bei 90% der Patienten das Vorhandensein von oligoclonalen Zonen nachweisbar war. Was die anderen neurologischen Erkrankungen betrifft, so war in 35,1% der Fälle der IgG-Index abnormal erhöht, während IgG-Bänder im Liquor nur bei 1,5% sowie beide bei 7% der Patienten im Liquor und im Serum vorhanden waren. Bei der Diagnose Multiple Sklerose wird der Isoelektrischen Fokalisation der höchste diagnostische Wert zugesprochen, um IgG-oligoclonale Bänder im Liquor nachzuweisen.

     

Clinical significance of serum and CSF findings in the Guillain-Barré syndrome and related disorders

Summary Clinical data and the serum and cerebrospinal fluid (CSF) findings of 71 patients with Guillain-Barré syndrome (GBS), 7 with Fisher syndrome and 24 with chronic inflammatory polyradiculoneuropathy (CIP), were analysed. Isoelectric focusing of serum and CSF together with different formulae and diagrams were applied to study blood-CSF barrier (BCB) function and possible intrathecal IgG synthesis. The CSF total protein concentration and its IgG percentage depended mainly on the degree of BCB damage, which correlated with the clinical course. Our investigations suggest that oligoclonal IgG of CSF from these patients comes essentially from serum. In the group of GBS patients, oligoclonal IgG was transitory and correlated significantly with the development of BCB damage, cranial neuritis and severity of the disease. CIP patients showed a stable IgG pattern, which varied slightly after immunosuppressive therapy.     

Oligoclonal IgG bands in cerebrospinal fluid and serum during asymptomatic human immunodeficiency virus infection

Serum and cerebrospinal fluid (CSF) samples from asymptomatic patients seropositive for human immunodeficiency virus (HIV) showed frequent evidence of intrathecal IgG synthesis and oligoclonal IgG bands, with different isoelectric focusing patterns in serum and CSF; 2 of 7 had a CSF pleocytosis. The results suggest frequent, early, chronic central nervous system infection following HIV infection.     

Effect of treatment on oligoclonal IgG bands and intrathecal IgG synthesis in sequential cerebrospinal fluid and serum from patients with subacute sclerosing panencephalitis.

Oligoclonal IgG bands were analyzed in matching pairs of cerebrospinal fluid (CSF) and serum from 12 subacute sclerosing panencephalitis (SSPE) patients, using isoelectric focusing and immunofixation. Each patient was given isoprinosine, and four of the 12 patients were given alpha-interferon in addition. Two to 4 serial CSF and serum samples were collected from each SSPE patient during periods ranging from 1 to 16 months. In 3 SSPE patients a small number of new oligoclonal bands were seen in the follow-up CSF samples. In the other 9 SSPE patients there was no change in CSF band patterns between initial and follow-up specimens. Band patterns in serum remained unchanged between initial and follow-up samples. Although all 12 SSPE cases had higher IgG indices and increased rate of intra blood-brain barrier (BBB) IgG synthesis in comparison to patients with other neurological diseases, the values did not significantly differ between the first and follow-up specimens. We conclude that treatment of SSPE patients with isoprinosine or with isoprinosine and alpha-interferon had no significant effect on the CSF oligoclonal band profiles or IgG synthesis within the central nervous system.     

Chronic progressive myelopathy associated with HTLV-I: oligoclonal IgG and anti-HTLV-I IgG antibodies in cerebrospinal fluid and serum

Among 22 patients with human T-lymphotropic virus type I (HTLV-I)-associated chronic progressive myelopathy, agarose isoelectric focusing (AIF) revealed oligoclonal IgG bands in 21: in 3 in CSF only; in 11 in CSF and to some extent in serum; and in 7, identical patterns in CSF and serum. By immunoblot after AIF of CSF and serum, we observed bands of anti-HTLV-I IgG antibodies in 19 patients: in 5 in CSF only; in 9 in CSF and partly in serum; and in 5, identical in CSF and serum. Oligoclonal anti-HTLV-I IgG antibody bands could only partly be traced to oligoclonal IgG bands. If, prior to AIF, serum and CSF were absorbed with HTLV-I antigen, practically all oligoclonal HTLV-I-specific IgG antibody activity was abolished, while the oligoclonal pattern of total IgG was affected only to a minor extent. Alongside with HTLV-I-specific oligoclonal B cell response, HTLV-I myelopathy is regularly accompanied by production of oligoclonal IgG of unknown antibody specificities.     

Comparison between agarose gel electrophoresis and isoelectric focusing of CSF for demonstration of oligoclonal immunoglobulin bands in neurological disorders

Isoelectric focusing and agarose gel electrophoresis of CSF and serum revealed similar frequencies of oligoclonal bands in multiple sclerosis (100% with both methods), infectious CNS disorders (38 and 23%) and other neurological diseases (8 and 10%). In selected cases with unsure CSF oligoclonal bands on agarose gel electrophoresis, isoelectric focusing displayed definite oligoclonal bands. In contrast to agarose gel electrophoresis, isoelectric focusing revealed evidence for oligoclonal bands in serum as well as in CSF in 41% of the multiple sclerosis patients, indicating diffusion from CSF to serum. In 4 cases with gammaglobulin bands appearing in both CSF and serum on agarose gel electrophoresis, isoelectric focusing revealed normal CSF and serum protein patterns at pH above 6.4 where most IgG is migrating.     

Paraneoplastic antibodies detected by isoelectric focusing of cerebrospinal fluid and serum

Patients with paraneoplastic neurological syndromes often produce intrathecal antibodies. We have employed isoelectric focusing and peroxidase-labeled anti-IgG or 35S-labeled Hu or Yo antigens to identify oligoclonal bands (OCB) representing either total IgG or Hu or Yo antibodies in serum and CSF of patients with paraneoplastic encephalomyelitis (PEM) or paraneoplastic cerebellar degeneration (PCD). OCBs representing paraneoplastic antibodies were found in all CSF, but in only three sera. Yo antibodies represented the majority of IgG bands in PCD-CSF, which may reflect a limited immune response, whereas in PEM/SN, there were numerous additonal IgG bands of unknown specificity, indicating a broader immune response in these patients.     

Identification of light chain type bands in CSF and serum oligoclonal IgG from patients with multiple sclerosis

The light (L) chain types (kappa and lambda) of oligoclonal IgG bands of matching CSF and serum from 10 MS patients were identified in immunofixation after isoelectric focusing in polyacrylamide gel. Each specimen showed 10-15 oligoclonal bands in pH region of 7.5-9.3. In 7 MS CSF and 5 sera a greater number of oligoclonal IgG bands were of kappa (kappa)-type whereas in 3 CSF and 2 sera the majority was of lambda (lambda)-type. In 3 sera a clearcut correlation of bands with either type of L chain was not observed due to diffuse staining background. Only a small number of oligoclonal IgG bands in 7 of 10 CSF and serum pairs had identical isoelectric points and the same type of L chain. The results show that the individual MS patient had oligoclonal IgG bands in serum, differ with respect to number, isoelectric point and L chain type from the oligoclonal IgG profile seen in the patient's CSF.