Astrocytes synthesize and secrete prostaglandin D synthetase in vitro.

Prostaglandin D synthetase [PGD-S, prostaglandin-H2 D-isomerase, (5Z, 13E)-(15S)-9alpha, 11 alpha-epidioxy-15-hyrdroxyprosta-5,13-dienoate D-isomerase, EC 5,3,99,2], an enzyme that catalyzes the formation of prostaglandin D2, was originally isolated from homogenates of rat brain and spleen and is known to be a membrane-bound enzyme. Subsequent immunohistochemical studies have shown that PGD-S is associated with neurons in the brain of immature rats, whereas in adult rats it is associated with oligodendrocytes. Several recent studies have shown that the beta-trace protein isolated from human cerebrospinal fluid (CSF), the second most abundant protein in human CSF after albumin, is equivalent to PGD-S. In this paper, we report the preparation of a monospecific polyclonal antibody against purified PGD-S isolated from human CSF and the establishment of a specific radioimmunoassay for this protein. Using this radioimmunoassay in conjunction with immunoblot analysis, PGD-S was detected in various biological fluids including serum, aqueous humor, and rete testis fluid. In addition, an antibody prepared against human PGD-S partially cross-reacted with the PGD-S in the rat and ram. Using a monospecific polyclonal antibody prepared against purified rat PGD-S isolated from rat CSF in conjunction with [35S]methionine incorporation and immunoprecipitation techniques, it was shown for the first time that PGD-S is actively synthesized and secreted by astrocytes cultured in vitro, suggesting the astrocyte is the cellular origin of PGD-S in the CSF. The identification of the astrocyte as the cellular origin of this unique enzyme will allow the use of an in vitro system to study its regulation.

Cerebrospinal fluid proteins in multiple sclerosis.

Various CSF proteins were studied in 255 definite multiple sclerosis patients at various disease stages and compared with corresponding values obtained from 174 controls. The CSF changes in acute multiple sclerosis patients included a significant increase of total proteins and of gamma globulin, IgG, IgA, IgM, alpha-2 ceruloplasmin, 7S-gamma-1, and cytotoxic index for nerve cells in tissue culture, and significant decreases of pre-albumin, alpha-1, and alpha-2 and of the beta/gamma globulin ratio. The CSF levels of IgG, IgA, and IgM remained significantly higher in steroid-treated multiple sclerosis patients than in controls, but the levels often were significantly reduced while patients were on treatment or in remission. During remission or treatment with ACTH and/or steroids, the alpha-2 ceruloplasmin, 7S-gamma-1, and cytotoxic index were significantly reduced and the pre-albumin, alpha-1, and alpha-2 globulin classes and the beta/gamma ratio showed a tendency to return to normal.

Prostaglandin-D-synthase (beta-trace protein) levels in rat cerebrospinal fluid.

The precise role of prostaglandin-D-synthase (beta-trace protein), the major constituent of cerebrospinal fluid, is unclear. In the present study, a sensitive and highly specific fluoroimmunoassay was developed. The measurement of the enzyme levels in rat CSF revealed a developmental change in the CSF levels with the highest value of 66 +/- 8 microg/ml at 7 days after birth. No significant difference in the levels was seen between different times of day. Subcutaneous injections of all-trans retinoic acid caused a dramatic decrease in the protein levels in a dose- and time-dependent manner. These findings may raise the possibility that prostaglandin-D-synthase in CSF is involved in retinoic acid action on the brain.

Purification and N-terminal sequence of beta-trace, a protein abundant in human cerebrospinal fluid.

beta-Trace, a protein that represents a major constituent of human cerebrospinal fluid with unknown function has been purified to apparent homogeneity by gel chromatography and electrophoresis. After sodium dodecylsulfate electrophoresis on polyacrylamide gels (SDS-PAGE) and Western blotting, the N-terminal sequence (28 amino acids) has been determined. The high degree of identity with the corresponding sequences of prostaglandin D synthetase from rat (68%) and human (93%) suggests a strong relationship if not identity with this enzyme. Thus, 30 years after its discovery beta-trace might unravel as a well-known protein of the prostaglandin metabolism.

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.

The beta 2-microglobulin content of the cerebrospinal fluid in neurological disease.

Beta 2-Microglobulin levels in the CSF and serum of 125 neurological patients were determined. The concentration of beta 2-microglobulin in CSF and serum is approximately the same, ranging from 0.6--2.3 mg/l. No clear relationship could be found between the CSF beta 2-microglobulin level on the one hand and the total protein content and white cell count on the other. There was no clear relationship between the serum beta 2-microglobulin and CSF microglobulin content. An increase of beta 2-microglobulin in CSF was found most often in cases of serious infection of the meninges or of the central nervous system. An elevated beta 2-microglobulin content can occur as the only abnormal feature of the CSF.

Two-dimensional immunoelectrophoresis of unconcentrated cerebrospinal fluid.

The two-dimensional immunoelectrophoresis on cellulose acetate, already utilized for serum proteins, has been applied to CSF proteins. The technical modifications which allow the use of unconcentrated CSF are described. By utilizing a particularly suitable supporting medium, a good separation of proteins is achieved; consequently narrow-based peaks are obtained and the isoantigens can be displayed as distinct components in spite of closely similar migration velocities. The preliminary results of this method are given. Particulary interesting appears a beta-migrating protein and the gamma-migrating oligoclonal bands. The first may present an anodic cleavage suggesting that it may be the beta1C/beta1A-globulin. If this hypothesis is confirmed, the relative concentrations of the two components can be investigated. No clear-cut peaks corresponding to the gamma-migrating oligoclonal bands have been observed, their place being taken by a low precipitation line continuous with the IgG peak. The reasons for this phenomenon may be tentatively ascribed to a local specificity of these IgG.

Isoelectric focusing and electrophoresis of cerebrospinal fluid proteins in muscular dystrophies and spinal muscular atrophies.

In the very few previous investigations of the CSF-proteins in muscular dystrophies the results have generally been reported as normal. In spinal muscular atrophies a barrier-damage pattern of CSF-proteins has been found in amyotrophic lateral sclerosis (ALS). In the present investigation the CSF-proteins were examined by isoelectric focusing and quantitative paper electrophoresis in 13 patients with muscular dystrophies and in 11 patients with spinal muscular atrophies. On isoelectric focusing, CSF-protein abnormalities were found in 85% of the cases with muscular dystrophies and in all patients with spinal muscular atrophies. Differences in the CSF-protein patterns were observed within the group of muscular dystrophies and between these and the cases of spinal muscular atrophies. In ALS and in myotonic dystrophy, abnormal CSF-protein fractions occurred mainly in the alkaline pH-range, while in limb-girdle dystrophy and the patient with facioscapulohumeral dystrophy, aberrant fractions appeared mainly in the acidic region. CSF-protein abnormalities were found in both the alkaline fractions (HAFs) with pI 9.2-9.6 and a fraction with PI 7.1 were found in half of the patients with myotonic dystrophy. The CSF electrophoresis in myotonic dystrophy showed increased levels of beta1-globulin in all cases examined. Signs of barrier-damage were commonly encountered in ALS in contrast to the muscular dystrophies, except for myotonic dystrophy. The results are discussed in terms of possible diagnostic value and with regard to pathogenetic significance, particularly in relation to the current hypothesis of a neural involvement in muscular disorders.

Isoelectric focusing and electrophoresis of the CSF proteins in tremor of different origins.

The CSF proteins have previously been very little investigated in the cerebellar syndrome of chronic alcoholism and in essential tremor. Such studies have been carried out more thoroughly by electrophoretic methods in Parkinson's disease but generally with normal results. In the present investigation the CSF proteins were examined by isoelectric focusing and quantitative paper electrophoresis in 10 patients with the cerebellar syndrome of chronic alcoholsm, 12 patients with Parkinson's disease and 16 subjects with essential tremor. Abnormal CSF proteins of very similar appearance were found on isoelectric focusing in the acidic pH interval 5.6-5.8 in 80% of the patients with the cerebellar syndrome of chronic alcoholism. In Parkinson's disease the most common aberration was evidence of nonspecific blood-CSF-barrier damage which occurred in half of the patients. In only 17% of these cases did other alterations appear, situated in the pH range alkaline to pH 5.8. Abnormal CSF proteins were found in 94% of the patients with essential tremor. The aberrant proteins appeared in both the acidic and alkaline pH regions, most frequently with anisoelectric point at pH 5.9, 7.2 and 9.3. There was a considerably higher frequency of CSF protein abnormalities in different pH ranges in patients with tremor of more pronounced degree as compared to those with only mild symptoms. The electrophoretic examinations failed to show any conclusive alterations. Barrier-damage patterns of mild or moderate degree or slightly increased levels of CSF beta1-globulin were occasionally found in all 3 diseases. The results indicate that isoelectric focusing of the CSF proteins may be of diagnostic value in the cerebellar syndrome of chronic alcoholism and in essential tremor but does not reveal any characteristic abnormalities in Parkinson's disease.

Sodium dodecyl sulfate-capillary gel electrophoretic analysis of molecular mass microheterogeneity of beta-trace protein in cerebrospinal fluid from patients with central nervous system diseases.

Molecular mass (M(r)) microheterogeneity of beta-trace protein (beta TP) in cerebrospinal fluid (CSF) from patients with various neurological disorders was analyzed by sodium dodecyl sulfate capillary gel electrophoresis. Under the conditions employed, beta TP with a M(r) distribution of 23,000-30,000 was roughly separated into two subfractions containing the major peaks with M(r) of 26,000 and 28,500, respectively. The peak area ratios of the two subfractions of the electropherograms varied among the samples examined, and elevation in the total beta TP level in the CSF from patients with organic diseases in the central nervous system (CNS) was often accompanied by changes in the ratios of the subfractions. The quantitative changes in the subfraction level in CSF beta TP are considered to reflect the pathological alterations in the CNS.

Cerebrospinal fluid proteins in muscular dystrophy patients.

We analyzed and quantified the microcomponents of protein fractions in the cerebrospinal fluid of patients with various types of muscular dystrophy. The degenerative pattern is characterized by an increase in the prealbumin fraction and a decrease in the gamma-globulin fraction as shown in the Duchenne and congenital muscular dystrophy. The increase in CSF IgG, gamma-globulin fraction, and myelin basic protein is shown in the myotonic dystrophy. In addition to the lowness of IQ, and the abnormality of EEG and brain CT, abnormal CSF proteins obviously suggest the presence of CNS involvement in muscular dystrophy.

Lactoferrin, lysozyme, and beta 2-microglobulin levels in cerebrospinal fluid: differential indices of CNS inflammation.

The CSF levels of lactoferrin, lysozyme, and beta 2-microglobulin (beta 2 mu) were measured in patients with evident, probable, or possible inflammatory CNS reactions and compared to those found in neurologically apparently healthy patients. Patients with viral CNS infections had significantly raised beta 2 mu and lysozyme levels but normal lactoferrin levels, indicating a local activation of lymphocytes and monocytes but not of granulocytes. Patients with bacterial CNS infections had significantly raised levels of all three cell markers, but the increase of lysozyme and lactoferrin was relatively more pronounced than that of beta 2 mu, indicating that the inflammatory response to bacterial agents is dominated by monocytes and granulocytes. Patients with primary or secondary malignant brain tumors were characterized by a moderate increase of beta 2 mu and a considerable increase in both lysozyme and lactoferrin, i.e., the same protein pattern as observed in bacterial CNS infection. The lysozyme levels were moderately increased in half the patients with benign cerebral tumors while the levels of beta 2 mu and lactoferrin were normal, indicating that benign and malignant brain tumors induce different local inflammatory CNS reactions. Half the patients with pituitary gland adenoma had elevated beta 2 mu and lysozyme levels but normal lactoferrin levels, suggesting that immunological mechanisms are associated with the adenoma development. Patients with MS had moderately but significantly raised CSF levels of beta 2 mu and lysozyme and a third of them also had raised levels of lactoferrin, a protein pattern suggesting a low-active inflammatory process in CNS involving mononuclears and granulocytes. A similar protein pattern was found in Guillain-Barré syndrome. In cerebrosarcoidosis we noted considerably increased lysozyme and beta 2 mu but normal lactoferrin levels, consistent with the idea that the sarcoid granuloma mass is dominated by monocytic inflammatory cells. The data obtained indicate a clinical value of lactoferrin, lysozyme, and beta 2 mu as differential indices of inflammatory cell reactions taking place in various CNS processes.

Capillary electrophoretic analyses of beta-trace protein and other low molecular weight proteins in cerebrospinal fluid from patients with central nervous system diseases.

Ordinary capillary-zone electrophoresis (CZE), as well as CZE in a sodium dodecylsulfate-containing polymer solution (SDS-CZE) and capillary isoelectrofocusing (CIEF), was applied to the analysis of low molecular weight proteins in cerebrospinal fluid (CSF) from patients with various neuropsychiatric disorders. Under the CZE conditions employed, a peaks of beta-trace protein (beta TP), which is the most abundant low MW protein in CSF, was clearly detected on the electropherograms of all the samples examined, and the CSF beta TP level could be tentatively determined using allylamine added at a constant concentration as the internal standard. The results revealed that beta TP in CSF was non-specifically increased in organic disease in the central nervous system (CNS), especially in ones giving severe physical damage to the brain tissues. On the other hand, SDS-CZE allowed us to determine simultaneously the CSF minor low MW proteins other than beta TP, such as beta 2-microglobulin, gamma-trace protein, myelin basic protein, etc., while the CIEF electropherograms suggested that beta TP were separated into several fractions with the different PI values. These capillary electrophoresis systems seem to be powerful as aids in the biochemical examinations of beta TP and other low molecular weight proteins in CSF from patients with CNS diseases.

Human beta-trace in normal and pathological CNS tissues, genital organs and body fluids.

The function of BTP is still unknown. In CNS, the high amount of BTP in the white CNS matter and the glial cells as well as in genital organs of the stroma of epididymis suggest that BTP has a supportive function. Slight evidence of a synthesis in patients with MS and slightly increased CSF values in stroke patients may suggest that BTP is involved in repair mechanism of damaged brain tissue, or may be related from destroyed brain tissue. In samples of CSF, determination of BTP could be of value as differentiating glial cell tumors from tumors of other kinds, as well as the recently suggested diagnostic value of the Creutzfeldt-Jakob disease (20). However, also other functions of BTP has been suggested. (21, 22).

Agar gel electrophoresis of unconcentrated cerebrospinal fluid: the degenerative type.

Five to 10 mul of 196 cerebrospinal fluid samples were subjected to agar gel electrophoresis without previous concentration. No "degenerative" pattern was found to be correlated with any clinical diagnosis or group of diagnoses, Repeated freezing and thawing appears to have different effects on the different fractions. The oligoclonica gamma patterns in shown to be demonstrable by this method.

[Physico-chemical characteristics of human neurospecific beta 2 globulin]. / Fiziko-khimicheskaia kharakteristika neirospetsificheskogo beta2-globulina cheloveka.

Neurospecific beta 2-globulin was found to be a protein with molecular mass 20,000 +/- 2,000 daltons, exhibiting electrophoretic mobility of beta 2-globulins (0.29 +/- 0,05). Contrary to the S-100 protein the globulin was readily precipitated by ammonium sulfate at 30-60% of saturation. No carbohydrate and lipid components were found in the globulin. The beta 2-globulin appears to be a typical polypeptide.

[Antibody reaction to basic myelin proteins after intracisternal administration into animals]. / Deistvie antitel k osnovnomu belku mielina pri intratsisternal'nom vvedenii ikh zhivotnym.

Pathogenetic properties of antibodies to main protein of myelin, which are responsible for initiation of demyelinization process in the central nervous system, are discussed. Development of the process is accompanied by alteration in a number of biochemical reactions. Effects of the antibodies to main protein of myelin, after their intracisternal administration, are considered in relation to activation of proteolysis, alteration of glycolipid content and the functional state of the brain.