[Cerebrospinal fluid diagnostics in Germany since 1950 : Developments in the GDR and FRG in the context of society and science]. / Liquordiagnostik in Deutschland nach 1950 : Entwicklungen im Kontext von Wissenschaft und Gesellschaft in DDR und BRD.

The 40 years of separated development in two countries with extremely different political and social utopias allow consideration of the connection between science and society. The society-dependent development of cerebrospinal fluid (CSF) diagnostics in the German Democratic Republic (GDR) and the Federal Republic of Germany (FRG) is shown in the context of the international scientific development of the post-war era with new paradigms in physics, biology and genetics. As part of this contribution to the philosophy of science the consequences of the complex life science for a new view of disease research are discussed in contrast to the currently dominating, reductionistic medical industrial complex.

Intrathecal IgM synthesis in pediatric MS is not a negative prognostic marker of disease progression: quantitative versus qualitative IgM analysis.

BACKGROUND: Intrathecal IgM synthesis is reported to be associated with a worse prognosis in adults with multiple sclerosis (MS). OBJECTIVE: To study the predictive value of intrathecal IgM synthesis for the clinical course of pediatric MS. METHODS: Seventy children with onset of MS before the age of 16 years and followed for a median period of 10.4 years (range: 0.4-22.8 years) were studied. The two subgroups with (n=44) or without (n=26) intrathecal IgM synthesis were distinguished by a new, very sensitive, evaluation of quantitative analysis in cerebrospinal fluid (CSF)/serum quotient diagrams (Reibergrams). The clinical course and EDSS (Expanded Disability Status Scale) scores at five and ten years were compared with IgM frequencies between both groups with a new statistics program for CSF data. RESULTS: The cohort of children without intrathecal IgM production had higher numbers of attacks in the first two years and shorter time intervals between first and second attack, although this was not statistically significant (p=0.04, p=0.15 respectively). In addition there was also a trend for girls without intrathecal IgM synthesis to have a higher EDSS score after 10 years compared with the group with IgM synthesis. CONCLUSION: Intrathecal IgM synthesis is not associated with a more rapid progression of disability in pediatric MS. Reevaluation of data from previous reports about the negative predictive value of intrathecal IgM synthesis in adult MS with a CSF statistics tool show that the apparent contradiction is due to a methodological bias in the qualitative detection of 'oligoclonal' IgM or linear IgM index.

Paediatric and adult multiple sclerosis: age-related differences and time course of the neuroimmunological response in cerebrospinal fluid.

We investigate common pathophysiology in paediatric and adult multiple sclerosis (MS) by comparison of cerebrospinal fluid (CSF) data. We compared cerebrospinal fluid (CSF) data from eight patient groups with onset of MS at 7 to 29 years (n = 184). A new statistics program allows sensitive detection, quantifies the mean amount of intrathecal Ig synthesis in groups based on the 96% reference range of 4100 non-inflammatory controls, corrects for age-related increase of blood-derived albumin and immunoglobulins in CSF, and presents graphical data interpretation in Reibergrams. Already at onset of MS before puberty (< or =10 years) the frequency of intrathecal IgG synthesis (oligoclonal IgG) was 100% like in adults with 98%, but the amount of intrathecal IgG increases twofold during puberty. Intrathecal IgM synthesis is most frequent before and during puberty (in 57-67% of patients) compared with 41% in adults. The amount of intrathecal IgM synthesis before puberty is only 30% of that in adults. IgG and IgM Index are biased evaluations not suitable for characterizing age-related dynamics. A twofold age-related increase of the albumin quotient, Q(Alb), as a measure of the blood-CSF barrier function, represents normal physiological growth. Cell counts in CSF are low. The pre-puberty gender ratio is about 1:1. Intrathecal antibodies against measles, rubella and/or varicella zoster virus are detected in 73% of patients before puberty compared with 89% of adults. Individual paediatric patients (n = 17), with sequential punctures over 2-5 years, show constant quantities of intrathecal IgM and specific antibodies. In conclusion, paediatric MS already at first clinical manifestation shows the complete, neuroimmunological data pattern in CSF, i.e. inflammatory signs are not gradually evolving. Paediatric and adult MS differ quantitatively but not qualitatively in neuroimmunological patterns which does not allow for discrimination between 'early' and 'late' onset MS. CSF analysis may help to discriminate between acute and mono-symptomatic chronic inflammatory disease already at earliest clinical manifestation.

Quantitation of intrathecal antibodies in cerebrospinal fluid of subacute sclerosing panencephalitis, herpes simplex encephalitis and multiple sclerosis: discrimination between microorganism-driven and polyspecific immune response.

The detection of intrathecal antibody synthesis by qualitative methods or the Antibody-Index (AI) is a relevant tool for diagnosis of inflammatory neurological diseases. An increased AI can be observed for a causative antigen as well as part of a polyspecific immune response. The quantitation of the intrathecal antibody fraction in cerebrospinal fluid (CSF), F(S), helps to discriminate both cases. In contrast to AI, F(S) needs an absolute antibody concentration detected in the ELISA in mg/L. The intrathecally synthesized, "local" antibody concentration in CSF (AB(Loc)) is expressed as the specific fraction of the intrathecally synthesized total IgG (IgG(Loc)) in CSF with F(S)=AB(Loc)/IgG(Loc) x 100 in %. F(S) for HSV or measles has about 20- to 60-fold higher values in virus-caused antibody synthesis in acute herpes simplex encephalitis (mean HSV-F(S)=8.9%) or subacute sclerosing panencephalitis (mean measles-F(S)=18.8%) compared to the polyspecific immune response against these antigens e.g., in multiple sclerosis (0.14% or 0.52%, correspondingly). F(S) helps also to avoid misinterpretations of an increasing AI in cases of therapy control, and allows direct comparison of relative antibody concentrations (R(S)) in blood and intrathecally synthesized fractions in CSF (F(S)): In multiple sclerosis patients F(S):R(S) has a mean ratio of about 3 for the measles, rubella and VZV antibodies. Together with the large variability we find by ranking that about two third of MS patients have no direct correlation of the relative concentrations in serum and intrathecal synthesis. So this concept gains increasingly relevance for analysis of the polyspecific immune response in brain.

Cholesterol-lipid interactions in membranes. The saturation concentration of cholesterol in bilayers of various lipids.

1. The integration of cholesterol in a lipid bilayer can be visualized by changes in the fluorescence properties of the probe N-phenyl-1-naphthylamine (NPN). An increasing cholesterol content in the lipid phase corresponds to decreasing fluorescence intensity of NPN and a short wave shift of the emission spectrum. 2. Equilibrium constants for the partition of NPN between water and the various lipid phases are reported. An increasing cholesterol content in a bilayer decreases the solubility of NPN in the bilayer. 3. The saturation concentration of cholesterol in bilayers of various lipids prepared by ultrasonication is determined using the flourescence probe NPN. The maximal molar ratio of cholesterol : lipid is 2 : 1 for sphingomyelin or egg phosphatidylcholine and 1 : 1 for cerebroside, dipalmitoyl phosphatidylcholine, or dipalmitoyl phosphatidylethanolamine. 4. The comparison of the maximal molar ratio of cholesterol : lipid with the number of proton donor and proton acceptor sites in the lipid moiety is used for a discussion of the polar interactions of cholesterol within a lipid bilayer.

Vitamin B-6-catalyzed beta-elimination of serine and O-phosphoserine. Qualitative and quantitative aspects of catalytic influences at the rate-limiting step, a comparison with the rate of enzymatic beta-elimination.

The overall reaction rates for the beta-elimination of serine and O-phosphoserine, catalyzed by various vitamin B-6 analogs (pyridoxal 5'-phosphate, 5'-deoxypyridoxal and N-methylpyridoxal 5'-phosphate) in the presence or absence of Cu2+ ions, are determined. The comparison of the pH-dependence of the molar activities of the three vitamin B-6 aldehydes in beta-elimination of serine enables the characterization of the different active Schiff base species and the single catalytic events. The Schiff base which has a positive charge on the pyridine ring nitrogen and a fully ionized phosphate group shows the highest molar activity. The phosphate group acts as an intramolecular general base catalyst, most probably at the alpha-carbon proton of the amino acid. Furthermore general acid catalysis by buffer species occurs at the beta-hydroxy group serine. These facts together provide a kinetically unambiguous description of the mechanism of the reaction: the removal of the proton at the alpha-carbon atom of serine is the rate-limiting step and is followed by the more rapid elimination of the b-hydroxy group of serine. The forward rate constant of the rate-limiting step is calculated for each of the reactions mentioned. The rate constants are compared with respect to the effectiveness of the individual catalytic components in the vitamin B-6-dependent beta-elimination. For optimal conditions the reaction of O-phosphoserine is faster by a factor of 10(4) in the velocity of the beta-elimination than the corresponding acid-catalyzed beta-elimination of serine. For the eliminations at the alpha- and beta-carbon atoms of O-phosphoserine in vitamin B-6-catalysed reactions a common transition state is discussed. From a comparison of the fastest vitamin beta-6-dependent model reaction with the rate of an enzymatic beta-elimination it is suggested that for those beta-elininating enzymes where the rate-limiting step is the same as in the model, the catalytic components mentioned could suffice to explain the velocity of the rate-limiting step.

Relevance of cerebrospinal fluid variables for early diagnosis of neuroborreliosis.

We describe the specificity and sensitivity of measuring a combination of basic CSF variables and Borrelia burgdorferi (Bb)-specific IgG and IgM antibody index (AI) values for the diagnosis of early neuroborreliosis. Basic CSF variables included total cell count, quantitation of activated B cells (IgG, IgA, and IgM classes), CSF/serum quotient diagrams for IgG, IgA, and IgM (to quantitate brain-derived immunoglobulin fractions in CSF), and CSF/serum albumin ratio as a measure of blood-CSF barrier function. The Bb-specific component of immunoglobulins in CSF and serum was quantitated by ELISA. Results are based on data from CSF and serum of 24 patients with definite neuroborreliosis, 45 patients with other neurologic diseases, and 28 control individuals. Combined evidence of an elevated CSF cell count, IgM-class dominance in both the cellular and intrathecal humoral immune response, and blood-CSF barrier dysfunction yielded 70% diagnostic sensitivity and 98% diagnostic specificity for detection of neuroborreliosis. Intrathecal production of Bb-specific IgM, evaluated as Bb-specific IgM antibody index (Bb-IgM-AI; pathologic value > 1.4) showed 79% diagnostic sensitivity and 96% diagnostic specificity. Correspondingly, elevated Bb-specific IgG antibody index (Bb-IgG-AI; pathologic value > 1.4) displayed 63% diagnostic sensitivity and 89% diagnostic specificity. Combined analysis of Bb-specific AI values and basic CSF variables gave the highest sensitivity (80%) and specificity (98%). Analysis of CSF variables over a disease course showed that acute versus past disease could be discriminated by a combination of basic CSF variables and Bb-specific AI.(ABSTRACT TRUNCATED AT 250 WORDS)

Cyclosporin-A treatment of experimental allergic encephalomyelitis: changes in immunological regulation and blood-CSF barrier function.

Strain 13 guinea pigs at 18-21 days of age were sensitised with spinal cord and Freund's complete adjuvant to induce experimental allergic encephalomyelitis (EAE). Treatment with cyclosporin-A (CS-A) from one day before sensitisation until from 12 to 39 days after sensitisation resulted in a suppression of the disease. Suppression was indicated by an absence or reduction in severity of clinical signs together with a lack of increase in blood-cerebrospinal fluid (CSF) barrier permeability to proteins and a lower white cell count in the CSF from treated animals. When CS-A treatment was withdrawn, clinical disease reappeared but changes in IgG concentration in the CSF indicated that intrathecal synthesis of IgG had occurred, which was not the case in the untreated disease. Modification by CS-A of the immunoregulatory processes involved in the development of EAE, provides a model to study the special conditions which operate in neuroimmunological disorders.

Intercellular adhesion molecule-1 in cerebrospinal fluid--the evaluation of blood-derived and brain-derived fractions in neurological diseases.

The soluble intercellular adhesion molecule-1 (sICAM-1) was measured in paired CSF and serum samples from 128 patients with different neurological diseases. The reference range of blood-derived sICAM-1 fractions in CSF was characterized with reference to the albumin CSF/serum quotients. The low mean concentrations of sICAM-1 of normal controls (n=33) in CSF (1.5 ng/ml; C.V.=40%) compared to serum (285.1 ng/ml; C.V.=32%) indicate that about 60% to 80% of sICAM-1 in normal lumbar CSF derives from blood. This calculation is based on the theoretically expected molecular size-dependent blood-CSF gradient between 300:1 to 250:1. In patients with non-inflammatory diseases (n=21) the sICAM-1 CSF/serum quotient increased non-linearly with increasing albumin CSF/serum quotient (blood-CSF barrier dysfunction) displaying the shape of a saturation-like curve in contrast to hyperbolic curves of other blood-derived proteins in CSF. This non-linear relation between sICAM-1 and albumin quotients does not allow a linear index evaluation reported in earlier studies. In bacterial meningitis (n=31) and viral meningoencephalitis (n=28) in addition to the increased blood-derived fraction, the brain-derived fraction of sICAM-1 in CSF was up to 12-fold higher than that in controls. The sICAM-1 CSF/serum quotients in MS (n=15) did not differ from non-inflammatory controls, i.e., there was no brain-dependent sICAM-1 fluctuation in CSF in contrast to the known fluctuations in blood. Earlier published reports on sICAM-1 have been controversial due to less sensitive assays and unsuitable linear evaluation concepts for blood-CSF barrier dysfunction.

Chronic relapsing experimental allergic encephalomyelitis. Immunological and blood--cerebrospinal fluid barrier-dependent changes in the cerebrospinal fluid.

Cerebrospinal fluid (CSF) and plasma were taken from strain 13 guinea pigs in various stages of chronic relapsing experimental allergic encephalomyelitis using techniques which allowed repeated sampling from the same animal. Samples were assayed for albumin and IgG and the corresponding CSF/plasma quotients evaluated graphically using a method which could discriminate between blood-CSF barrier dysfunction and local IgG synthesis in the central nervous system (CNS). During the disease a 2-3-fold increase in plasma IgG concentration developed and an increase in blood-CSF permeability was noted. Isoelectric focusing revealed an oligoclonal IgG pattern identical in both plasma and CSF. The results provided no evidence for a local production of IgG in the CNS like that which is known to occur in multiple sclerosis.

Intrathecal release of sICAM-1 into CSF in neuroborreliosis--increased brain-derived fraction.

In the present study, we report sICAM-1 concentration in the cerebrospinal fluid (CSF) and serum of patients with neuroborreliosis (NB, n = 11), compared to the data from a control group of patients with corresponding blood/CSF barrier dysfunction but without inflammation in the central nervous system (disc prolaps, DP, n = 11). In NB, the sICAM-1 concentration in CSF was increased up to six-fold (ranges: 6.6-42.8 ng/ml and 2.2-9.8 ng/ml for NB and DP respectively) with no change in serum sICAM-1. The corresponding sICAM-1 CSF/serum concentration quotients (Q(ICAM)) were in the ranges: 22.5-171.3 X 10(-3), and 8.8-27.8 X 10(-3) for NB and DP respectively. This finding can be explained by increase of the brain-derived fraction of sICAM-1 in NB. In one case we observed increased Q(ICAM) on 6th day after admission to the hospital (171.3 X 10(-3) at the time of the first lumbar puncture slightly increasing to 243.6 x 10(-3) five days later), followed by normalization, in two remaining repunctured patients we observed decreasing QICAM with normalizing Q(Alb).

The discrimination between different blood-CSF barrier dysfunctions and inflammatory reactions of the CNS by a recent evaluation graph for the protein profile of cerebrospinal fluid.

A graph for the evaluation of the CSF-protein profile is presented as a basic program for the clinical-neurochemical laboratory. The graph has the following advantages: Simultaneous information on the functional state of the blood-CSF barrier and the inflammatory response of the CNS; maximal sensitivity for the determination of a pathological local IgG production in CNS--with the possibility of calculating the IgG fraction in CSF originating from the CNS; minimal number of protein assays necessary (albumin and IgG in serum and CSF); suitable for the demonstration of the course of the disease in a single patient as well as for demonstration of a group of cases for statistical purposes. Complementary chemical investigations and the correspondence with the clinical diagnosis are discussed for a number of typical cases. Two different types of blood-CSF barrier dysfunctions are discriminated by a proportional and a dis-proportionate increase of the CSF/serum protein concentration gradients.

The clinical relevance of locally produced carcinoembryonic antigen in cerebrospinal fluid.

Sixteen out of eighteen meningeal carcinomas (89%) secreted carcinoembryonic antigen (CEA) into the cerebrospinal fluid, where it could be quantified separately from the portion originating from the circulating blood. The discrimination of both fractions was performed according to an empirical approach analogous to the immunoglobulins. Only 47% of the intraparenchymal carcinomas released CEA into the CSF compartment and it is possible that the extra-cellular space of these tumour sites does not communicate with the free CSF space. Extradural metastases may cause an impairment of the blood-CSF barrier via restrictions of the CSF fluid turnover, but the dura remains impermeable for the tumour marker. Seven out of 54 primary brain tumours (13%) released carcinoembryonic antigen into the cerebrospinal fluid.

Tau protein in cerebrospinal fluid (CSF): a blood-CSF barrier related evaluation in patients with various neurological diseases.

Tau protein (tau) is primarily localised in neurons, and after brain parenchymal damage its release into cerebrospinal fluid (CSF) is increased. The particular influences of blood-CSF barrier function and of disease topography on CSF tau levels have not been studied yet. CSF tau concentrations determined by enzyme-immunoassay in various neurological diseases (n = 61) were not dependent upon blood-CSF barrier dysfunction. Significant elevation of tau levels in patients with meningoencephalitis and cerebral hemorrhage indicates brain parenchymal damage. In contrast, tau levels remained normal in patients with bacterial meningitis if encephalitic complications did not occur. In patients with Guillain-Barré syndrome tau levels were low. Increased tau levels in active multiple sclerosis compared to clinically nonactive states indicate axonal pathology in active disease.

Beta-trace protein concentration in cerebrospinal fluid is decreased in patients with bacterial meningitis.

Although meninges represent a major site of biosynthesis, beta-trace protein (beta-trace) has not been studied in the cerebrospinal fluid (CSF) of meningitis patients. We measured beta-trace in lumbar CSF of normal controls (n = 27) and in patients with various neurological diseases (n = 92) by an immunonephelometric assay. The mean concentration of beta-trace in CSF of control patients was 16.6+/-3.6 mg/l. In bacterial meningitis (n = 41), CSF beta-trace was significantly decreased (8.7+/-3.9 mg/l; P< 0.001), whereas in spinal canal stenosis it was elevated (29.2+/-10.3 mg/l; P= 0.002). In viral meningoencephalitis (n = 12), beta-trace CSF concentrations were normal. Beta-trace concentrations remained below the normal range even after curing of bacterial meningitis, and normalisation of CSF leucocytes and blood-CSF barrier function. Beta-trace may be a useful tool for studying the pathophysiology of bacterial meningitis.

Flow rate of cerebrospinal fluid (CSF)--a concept common to normal blood-CSF barrier function and to dysfunction in neurological diseases.

Many neurological diseases are accompanied by increased protein concentrations in the cerebrospinal fluid (CSF), described as a blood-CSF barrier dysfunction. The earlier interpretation as a "leakage" of the blood-CSF barrier for serum proteins could be revised by introduction of a "population variation coefficient" of the CSF/serum quotients for IgG, IgA and IgM (delta Q/Q) which is evaluated as a function of increasing albumin quotients (QAlb). The data presented here are based on specimens from 4380 neurological patients. These population variation coefficients were found to be constant over two orders of magnitude of normal and pathological CSF protein concentrations (QAlb = 1.6.10(-3)-150.10(-3)). This constancy indicates that there was no change in blood-CSF barrier related structures with respect to diffusion controlled protein transfer from blood into CSF and hence no change in molecular size dependent selectivity. The pathological increase of plasma protein concentrations in CSF in neurological diseases could also be explained quantitatively by a decrease of CSF flow rate due to its bifunctional influence on CSF protein concentration: reduced volume exchange, and as newly stated, increased molecular net flux into CSF without change of permeability coefficients. Again, on the basis of a changing CSF flow rate, the hyperbolic functions, which describe empirically the changing quotient ratios between proteins of different size (e.g. QIgG:QAlb) with increasing CSF protein content (QAlb) can likewise be derived from the laws of diffusion as the physiologically relevant description. The hyperbolic discrimination line between brain-derived and blood-derived protein fractions in CSF in the quotient diagrams for CSF diagnosis can be further improved on the basis of the large number of cases investigated. Other physiological and pathological aspects, such as high CSF protein values in the normal newborn, in spinal blockade, in meningeal inflammatory processes, CNS leukemia or polyradiculitis as well as animal species dependent variations can each be interpreted as due to a difference or change in the CSF flow rate.

Cerebrospinal fluid analysis: disease-related data patterns and evaluation programs.

Cerebrospinal fluid (CSF) analysis is a basic tool for diagnosis of neurological diseases. Knowledge regarding blood-CSF barrier function (molecular flux/CSF flow theory) and neuroimmunology is reviewed to aid understanding and evaluation of CSF data. Disease-related immunoglobulin patterns (IgG, IgA, IgM with reference to albumin) are described in CSF/serum quotient diagrams with the hyperbolic reference range for blood-derived protein fractions in CSF. Clinical relevance of complementary analyses (cytology, PCR, oligoclonal IgG, antibody detection and brain-derived proteins) is briefly discussed. Integrated CSF data reports are shown with numerical and graphical data representation, reference range-related interpretation and diagnosis-related comments. The principles and rationale of general CSF analysis reported in this review should enable the reader to accurately interpret CSF data profiles, and to plan a proper evaluation of new brain- or blood-derived analytes in CSF.

Amino acid transport across the human blood-CSF barrier. An evaluation graph for amino acid concentrations in cerebrospinal fluid.

The correlation of cerebrospinal fluid (CSF)/serum concentration quotients was used as a method for identification of amino acids which are transported by a common carrier system across the blood-CSF barrier. Isoleucine, leucine, valine, phenylalanine, tyrosine and lysine were found to compete for the same carrier system. This group of amino acids in man was found to be different from the system described as a neutral amino acid carrier at the blood-brain barrier in rats. In man, methionine and tryptophan do not compete with the other neutral amino acids for the same carrier system. In contrast, lysine as a basic amino acid is found to be correlated with the same transport system as the five neutral amino acids. A graph for the evaluation of pathological amino acid concentrations in CSF is presented. Patients with a blood-CSF barrier dysfunction for proteins showed partly normal, partly increased, CSF/serum concentration quotients for the amino acids. Hydroxyproline could be identified as a constituent of the amino acid pool in CSF. For proline and hydroxyproline a special control system has to be suggested because of their smaller biological variance in CSF than in blood. Contrary to the other amino acids proline and hydroxyproline have a smaller biological variation in CSF than in serum.

The effect of Freund's adjuvants on blood-cerebrospinal fluid barrier permeability.

In guinea pigs with experimental allergic encephalomyelitis induced by spinal cord homogenate--complete Freund's adjuvant (CFA) emulsions an increase in the albumin permeability of the blood--cerebrospinal fluid barrier occurred from day 10 post-inoculation (p.i.) onward. In animals inoculated with CFA alone an increased albumin permeability was also demonstrated but only between days 5 and 10 after inoculation; by day 14-16 p.i. the barrier permeability had returned to control values. A similar change was seen in animals inoculated with incomplete Freund's adjuvant (IFA) only. However, both CFA and CFA-cord induced a strong humoral immune response which was not seen in animals inoculated with IFA alone. These results may have important consequences for the understanding of the development of inflammatory diseases of the central nervous system.