Human Central Nervous System Tissue Research Articles

Expression of the 14E Antigen in Glial Cells in Human Normal and Pathological Central Nervous System Tissuesa

Expression of the 14E Antigen in Glial Cells in Human Normal and Pathological Central Nervous System Tissues^a

Common immunologic determinant between human immunodeficiency virus type 1 gp41 and astrocytes

Monoclonal antibodies against a synthetic 12-amino-acid peptide that comprises the immunodominant domain of human immunodeficiency virus type 1 gp41 (amino acids 598 through 609) reacted with astrocytes found in human and rodent central nervous system tissue. The monoclonal antibodies bound to a 43-kDa protein found in central nervous system tissue preparations. These results indicate that human immunodeficiency virus type 1 gp41 contains a common epitope with astrocytes and that an immune response to human immunodeficiency virus type 1 gp41 could generate antibodies that are cross-reactive to astrocytes. Furthermore, anti-astrocyte antibodies, which were directed at a common epitope with the gp41 sequence, were found to be present in cerebrospinal fluid from some AIDS patients with central nervous system complications. Astrocytes regulate the environment for appropriate neuronal function, and astrocyte hyperactivity (astrocytosis) is known to be the common and early pathologic event in brains from patients with central nervous system AIDS. We suggest that antibody-induced effect(s) on astrocytes could lead to the physiologic neuronal dysfunctions observed in AIDS patients.

Detection of HIV in fetal central nervous system tissue

Neurological disease is a common finding in children with AIDS and in others without signs of disease but with evidence of congenital HIV-1 infection. To investigate the possibility that HIV-1 can infect fetal central nervous system (CNS) tissue and therefore possibly serve as the substrate for the abnormal neurodevelopment characteristic of pediatric AIDS, eight abortus CNS samples (one set of twins) from seven HIV-1-seropositive intravenous drug users (IVDUs) and eight control abortus CNS samples from eight HIV-1-seronegative IVDUs were analyzed for HIV-1 infection. HIV-1 nucleic acid was detected only after the use of polymerase chain reaction (PCR) in three of eight CNS samples from HIV-seropositive IVDUs but not in samples from seronegative subjects. In situ hybridization confirmed that HIV-1 DNA sequences were in cells in the CNS parenchyma of two of the three positive samples. This study demonstrates that HIV-1 can infect human fetal CNS tissue in vivo, but that the use of PCR may be necessary for its detection.

Rapid separation of tritiated thyrotropin-releasing hormone and its catabolic products from mouse and human central nervous system tissues by high-performance liquid chromatography with radioactive flow detection

Reversed-phase high-performance liquid chromatography with radioactive flow detection was utilized to investigate the catabolism of thyrotropin-releasing hormone (TRH) in central nervous system (CNS) tissues. Two different column/gradient solvent systems were tested: (1) octadecylsilane (ODS) with an acetic acid-acetonitrile gradient and (2) poly (styrenedivinylbenzene) (PRP-1) with a trifluoroacetic acid-acetonitrile gradient. Both systems used 1-hexanesulfonic acid as the second ion-pairing reagent and yielded excellent separation of TRH and its catabolic products, TRH acid, cyclo (histidyl-proline), histidyl-proline, proline, and prolinamide, produced in CNS tissue homogenates. The PRP-1 column with a trifluoroacetic acid-acetonitrile solvent system produced a better and more reproducible separation of TRH catabolic products than the ODS column with the acetic acid-acetonitrile solvent system. This PRP-1 technique was utilized to demonstrate different rates and products of TRH catabolism in mouse and human spinal cord compared with cerebral cortex.

Collection and Use of Fetal Central Nervous System Tissue

A recent promising development in the field of central nervous system (CNS) tissue transplantation has suggested the use of human fetal CNS tissue from first trimester abortions for xenografting/explantation. Such experiments would certainly expand our knowledge of the normal developmental mechanisms in the human CNS, and allow studies of various indices of maturation and CNS function. However, the suggestion is looked upon with hesitance for ethical, legal and perhaps even for scientific reasons. The initial experiments have been very valuable, though, for our understanding of the structural and functional development of the human CNS, and several legal and ethical concerns have been addressed in working out the procedures for retrieving such tissue. This article tries to put our present knowledge in the right perspective of scientific achievements and potential, legal restrictions and ethical concerns.

Identification of the normal microglial population in human and rodent nervous tissue using lectin-histochemistry.

Mistletoe lectin-1 (ML-1) and Ricinus communis agglutinin-120 (RCA-1) both possess D-galactose-specific surface-binding sites. They were used to selectively identify microglial populations in aldehyde-fixed normal brain tissue by lectin immunohistochemistry on paraffin and frozen sections. Mistletoe lectin-1 was superior to RCA-1 in labelling microglia in the rat brain, whereas RCA-1 labelled human microglia better than ML-1. Thus, RCA-1 and ML-1 supplement each other for identifying microglial in human and rodent central nervous system tissues. The high reproducibility of the results and the applicability of the technique to routine histology, using formalin-fixed tissue, should facilitate study of the histogenesis and role of microglia in the CNS.

Collection and use of aborted central nervous system material. Commendation and controversy.

A recent promising development in the field of central nervous system (CNS) transplantation has suggested the use of human fetal CNS tissue from first trimester abortions for xenografting/explantation. Such experiments would certainly expand our knowledge of the normal developmental mechanisms in human CNS, and allow studies of various indices of maturation and CNS function. However, the suggestion is looked upon with hesitance for ethical, legal and perhaps even for scientific reasons. The initial experiments have been very valuable, though, for our understanding of the structural and functional development of the human CNS, and several legal and ethical concerns have been addressed in working out the procedures for retrieving such tissue. This article tries to put our present knowledge in the right perspective of scientific achievements and potential, legal restrictions and ethical concerns.

Immunohistochemical demonstration of proteinase inhibitor alpha-1-antichymotrypsin in normal human central nervous system.

The presence of alpha-1-antichymotrypsin, a serine proteinase inhibitor with a high affinity for cathepsin G, is demonstrated in the normal human central nervous system (CNS) by immunohistochemical techniques. Paraffin-embedded normal human CNS tissue from five adult, two fetal, one neonatal and three newborn autopsies were stained with monospecific rabbit antibodies to human alpha-1-antichymotrypsin using biotinylated goat anti-rabbit antibodies and an avidinbiotin-peroxidase complex. Positive immunostaining was seen in neurons and glial cells in the cerebral cortex, basal ganglia, hippocampus, cerebellum, brainstem, and spinal cord of the adults. The epithelium of the adult choroid plexus had the most intense staining in apical granular organelles corresponding in position to lysosomes or secretory granules. Ependymal cells, particularly those near the choroid plexus, were immunostained. The fetal CNS had no alpha-1-antichymotrypsin staining. Limited staining of choroid plexus, ependyma, and frontal lobe was found in the newborns. Immunostaining in the neonatal temporal lobe was only found in the choroid-plexus epithelium. These observations establish a widespread distribution of this proteinase inhibitor in the normal human CNS. Developmental regulation of this inhibitor in the human CNS is also indicated.

Monoclonal antibody to aldolase C: a selective marker for Purkinje cells in the human cerebellum.

A monoclonal antibody to the glycolytic enzyme aldolase C was used in an immunoperoxidase technique on unfixed and formalin-fixed paraffin-embedded tissues from the human central nervous system (CNS) and other tissues. No staining outside the CNS was detected. In the central nervous system the antibody gave a selective and intense staining of Purkinje cell perikarya, axons and dendrites in both fixed and unfixed tissues. In the human fetal brain, positive staining of Purkinje cells was seen from 35-36 weeks' gestation onwards. This coincides with the conversion of Purkinje cells to a tetraploid state, and may reflect increased glycolytic activity accompanying the rapid dendritic growth at this stage of development. Preliminary investigations on a variety of disease states suggest that this antibody may be useful in studies of ischaemic damage, congenital abnormalities and degenerative conditions affecting the cerebellum.

Monoclonal antibody to macrophages (EMB/11) labels macrophages and microglial cells in human brain.

Normal and diseased human central nervous system (CNS) tissues were studied immunohistochemically by a monoclonal antibody to human macrophages (EBM/11), antisera to glial fibrillary acidic protein (anti-GFAP), and alpha-1-antichymotrypsin (alpha 1-ACT). EBM/11 reacted with brain macrophages located mainly around blood vessels in normal brain; it also reacted with resting microglia in normal brain and with numerous reactive microglia and macrophages in brain tumours and inflammatory lesions. Microglia did not react with anti-GFAP or alpha 1-ACT. An EBM/11 positive phenotype, therefore, is shared by microglia and macrophages and suggests that microglial cells form a specialised part of the mononuclear phagocyte system.

Characterization of peptide alpha-amidation activity in human cerebrospinal fluid and central nervous system tissue.

Peptidyl-glycine alpha-amidation activity has been detected in human cerebrospinal fluid (CSF) and in several regions of the central nervous system. Activity was monitored by measuring conversion of mono-125I-D-Tyr-Val-Gly into mono-125I-D-Tyr-Val-NH2. The alpha-amidation activity in CSF is dependent on molecular oxygen, copper ions and ascorbic acid and appears to recognize a variety of peptide substrates which contain carboxyl terminal glycine residues. Kinetic analyses demonstrated Michaelis-Menten kinetics with a Km of 4.6 microM for D-Tyr-Val-Gly. The level of peptidyl-glycine alpha-amidation activity in 14 samples of CSF averaged 43 +/- 5 pmol/ml/h (mean +/- SEM; range 11-85 pmol/ml/h) or 1.9 +/- 0.2 pmol/Mg protein/h. No difference was noted between samples from male and female subjects. Extracts of central nervous system tissue contained alpha-amidation activity. The highest levels of enzyme activity were found in the hypothalamus with lower levels in the neurohypophysis and the cerebral cortex. Still lower but detectable activity was found in the cerebellum and pons. Human peptidyl-glycine alph-amidation activity is found in central nervous system tissues known to synthesize alpha-amidated neuropeptides and may be secreted from these tissues along with alpha-amidated peptides into CSF.

Lectin target cells in human central nervous system and the pituitary gland.

Peanut lectin (PNL), Concanavalin A (Con A) and Ulex europaeus lectin I (Ulex) were chosen to map their binding sites in different regions of formalin fixed and paraffin embedded human central nervous system tissue and pituitary gland tissues. An extended PaP method was used for PNL and Ulex, whereas a direct peroxidase technique was employed for Con A. In astrocytes, the cytoplasm as well as the delicate processes were stained by PNL and Con A; the most conspicuous binding of PNL was seen in the ependymal cells and on the surface of plexus epithelial cells; in the anterior part of the pituitary gland a selective population was PNL positive. Intracytoplasmic Con A acceptors could be demonstrated in neurons, in ependymal cells, and in plexus epithelial cells. Intracytoplasmic Con A receptors were finely granular in astrocytes, oligodendrocytes, and in some cells in the pituitary gland. Ulex binding was restricted to the vascular endothelial cells and a selective population of cells in the pituitary gland. Our results suggest that lectins may be good tools for the evaluation of their respective target cells in the central nervous system and in the pituitary gland.

The Spleen in Myeloproliferative Disorders

Neuropathic pain is a chronic, refractory condition that arises after damage to the nervous system. We previously showed that an increased level of the endogenous metabolite N,N-dimethylsphingosine (DMS) in the central nervous system (CNS) is sufficient to induce neuropathic pain-like behavior in rats. However, several important questions remain. First, it has not yet been demonstrated that DMS is produced in humans and its value as a therapeutic target is therefore unknown. Second, the cell types within the CNS that produce DMS are currently unidentified. Here we provide evidence that DMS is present in human CNS tissue. We show that DMS levels increase in demyelinating lesions isolated from patients with multiple sclerosis, an autoimmune disease in which the majority of patients experience chronic pain. On the basis of these results, we hypothesized that oligodendrocytes may be a cellular source of DMS. We show that human oligodendrocytes produce DMS in culture and that the levels of DMS increase when oligodendrocytes are challenged with agents that damage white matter. These results suggest that damage to oligodendrocytes leads to increased DMS production which in turn drives inflammatory astrocyte responses involved in sensory neuron sensitization. Interruption of this pathway in patients may provide analgesia without the debilitating side effects that are commonly observed with other chronic pain therapies.

Monoclonal anti-T cell antibodies are applicable to the study of inflammatory infiltrates in the central nervous system

Monoclonal anti-human T cell antibodies were tested by a modified PAP technique on frozen sections of human central nervous system (CNS) tissue from inflammatory and non-inflammatory conditions. It was found that whole T cells and T cell subset - T4+ (helper-induced)_ and T8+ (suppressor/cytotoxic) T cells - could could be differentiated specifically from other mononuclear cells and their these markers did not cross-react with human CNS tissue elements, particulary oligodendrocytes, under the same conditions. The lack of cross-reactivity between monoclonal antibodies to T cells and oligondendrocytes was further confirmed by double-labelling with an anti-galactocerebroside serum. It is concluded that in inflammatory condition like multiple sclerosis, monoclonal antibodies promise considerable elucidation of immunopathogenetic events.

Properties of Fc gamma receptors in the human central nervous system.

Cryostat sections of human central nervous system (CNS) tissue absorbed sheep erythrocytes (E) sensitized with rabbit IgG antibody (A). The indicator cells bound to the choroid plexus, to the leptomeninges covering the brain and spinal cord, to the arachnoid granulations and to the perivascular tissue of the neural parenchyma. Unsensitized E or E sensitized with F(ab')2 fragments of IgG were not bound. The reactions were inhibited by pooled human IgG, human IgG1 and IgG3 myeloma proteins, and Fc fragments of pooled human IgG. Whole human IgG2 myeloma protein, IgM, IgA, F(ab')2 fragments of pooled human IgG and albumin did not inhibit. Experiments with reduced and alkylated IgG, EDTA, iodoacetamide, 2-mercaptoethanol, various pHs and salt concentrations, formaldehyde, periodic acid and neuraminidase did not reveal any differences between the Fc gamma receptors in the separate anatomical areas. The Fc gamma receptors in human CNS are thus apparently very similar.

A survey of substance P, somatostatin, and neurotensin levels in aging in the rat and human central nervous system

Levels of the neuropeptides substance P, somatostatin, and neurotensin were measured by radioimmunoassay in regions of the rat and human central nervous system (CNS) in aging. Somatostatin levels were significantly lower only in the corpus striatum of older rats. Substance P levels and neurotensin levels were generally stable with aging as were levels of somatostatin in regions other than the corpus striatum. In post-mortem human CNS tissues, no significant negative correlations of levels of the three peptides were observed with time to refrigeration or time to freezer for the samples. In the human CNS, there were no significant age-related alterations in substance P levels in frontal cortex, thalamus, hypothalamus, caudate nucleus, globus pallidus, or substantia nigra. There was a significant age-related decrease in substance P levels in the human putamen. This age-related decrease was not present in tissues from victims of Huntington's disease nor was there any striking difference in substance P levels as a function of duration of the disease. There were no significant age-related changes in somatostatin levels in human frontal cortex, caudate nucleus, putamen, medial globus pallidus, or substantia nigra. Among these same regions, there was a significant age-related decrease in neurotensin levels only in the pars compacta and pars reticulata of the human nigra. These results implicate neuropeptides in aging processes in certain regions of the CNS. There are differences between rats and humans with respect to neuropeptides in the aging process in the CNS. Deterioration of some neuropeptide pathways in and to human basal ganglia may be involved in the suspected functional deterioration of parts of the extrapyramidal system in aging.

PROTHROMBIN IN ENZYMOLOGY, THROMBOSIS AND HEMOPHILIA

Normal and diseased human central nervous system (CNS) tissues were studied immunohistochemically by a monoclonal antibody to human macrophages (EBM/11), antisera to glial fibrillary acidic protein (anti-GFAP), and alpha-1-antichymotrypsin (alpha 1-ACT). EBM/11 reacted with brain macrophages located mainly around blood vessels in normal brain; it also reacted with resting microglia in normal brain and with numerous reactive microglia and macrophages in brain tumours and inflammatory lesions. Microglia did not react with anti-GFAP or alpha 1-ACT. An EBM/11 positive phenotype, therefore, is shared by microglia and macrophages and suggests that microglial cells form a specialised part of the mononuclear phagocyte system.

Isolation and Properties of an Encephalitogenic Protein from Bovine, Rabbit, and Human Central Nervous System Tissue

Abstract Sodium citrate extracts of acetone-ether-defatted rabbit, bovine, and human central nervous system tissue were chromatographed on carboxymethyl cellulose and Sephadex G-50. From each of these three tissues a protein was isolated which produced experimental allergic encephalomyelitis in 90% of recipient rabbits. The disc polyacrylamide gel electrophoretic pattern of the protein was consistent with a high degree of homogeneity. The basic amino acids constituted nearly 25% of the total. There was no half-cystine and only traces of methionine and isoleucine. Phenylalanine accounted for 90% or more of the amino-terminal amino acids, and tryptic digestion of the untreated protein gave 8 to 10 major peptide spots. The sedimentation of the protein in a 10 to 20% sucrose gradient, its elution volume from a Sephadex G-50 column, and calculations based on the results of amino acid analysis and dinitrophenylation were all consistent with a molecular weight of 4000 to 8000.