Inflammatory cells, microglia and MHC class II antigen-positive cells in the spinal cord of Lewis rats with acute and chronic relapsing experimental autoimmune encephalomyelitis

Chronic relapsing experimental autoimmune encephalomyelitis (CR-EAE) was induced in Lewis rats by inoculation with guinea pig spinal cord and adjuvants and treatment with low dose cyclosporin A (CsA). Acute EAE was induced by the same method without CsA treatment. Immunocytochemistry and flow cytometry were used to assess inflammatory cells and MHC class II (Ia) antigen expression in the central nervous system of these rats. The inflammatory infiltrate was composed mainly of CD4⁺ T cells and macrophages, and αß T cells constituted about 65% of the CD2⁺ T cells. After recovery from acute EAE and during the first remission of CR-EAE, the number of T cells was significantly less than in the preceding episodes. The number of T cells was higher in the second episode of CR-EAE than in the first remission. Throughout the course of CR-EAE, the majority of the CD2⁺ T cells were CD45RC⁻. The ratio of IL-2R⁺ cells to CD2⁺ cells ranged from 10.5 to 24.0%. The ratio of CD4⁺ T cells to B cells was lower in the later episodes of CR-EAE than in the first episode. Ia antigen was expressed on filtrating round cells at all stages of CR-EAE and on microglial cells (identified by dendritic morphology) with increasing intensity throughout the course of CR-EAE. With flow cytometry, the number of Ia⁺ cells obtained from the spinal cord rose throughout the course of CR-EAE. The number of FSC^lowOX1^low cells, which we consider represent microglia, also increased during the course of CR-EAE.     

Development of microglial topography in human retina

The development of microglial topography in wholemounts of human retina has been examined in the age range 10–25 weeks gestation (WG) using histochemistry and immunohistochemistry for CD45 and major histocompatibility complex class II antigens. Microglia were present in three planes corresponding to the developing nerve fibre layer/ganglion cell layer, the inner plexiform layer and the outer plexiform layer. Distribution patterns of cells through the retinal thickness and across the retinal surface area varied with gestational age. Microglia were elongated in superficial retina, large and ramified in the middle plane, and small, rounded and less ramified in deep retina. Intensely labeled, rounded profiles seen at the pars caeca of the ciliary processes, the retinal margin and at the optic disc may represent precursors of some retinal microglia. At 10 WG, the highest densities of microglia were present in middle and deep retina in the far periphery and at the retinal margin, with few superficial microglia evident centrally at the optic disc. At 14 WG, high densities of microglia were apparent superficially at the optic disc; microglia of middle and deep retina were distributed at more central locations although continuing to concentrate in the retinal periphery. Microglia appear to migrate into the developing human retina from two mains sources, the retinal margin and the optic disc, most likely originating from the blood vessels of the ciliary body and iris, and the retinal vasculature, respectively. The data suggest that the development of microglial topography occurs in two phases, an early phase occurring prior to vascularization, and a late phase associated with the development of the retinal vasculature. © 1995 Wiley-Liss, Inc.     

不同类型颅咽管瘤的组织炎症和细胞增殖性

目的研究不同病理类型颅咽管瘤的组织炎症及细胞增殖性对预后的影响.方法对30例经手术切除的颅咽管瘤组织采用免疫组织化学SP法检测白细胞共同抗原CD45和细胞周期相关核抗原Ki-67的抗体MIB-1的表达,分别计算CD45标记指数(CD45 LI)和MIB-1标记指数(MIB-1 LI).结果CD45标记的炎症反应在颅咽管瘤组织中广泛存在,MIB-1主要在颅咽管瘤基底细胞层表达.造釉细胞型颅咽管瘤组织CD45 LI(32.4%±15.0%)及细胞MIB-1 LI(18.2%±8.7%)显著性高于鳞状乳头型颅咽管瘤(分别为13.6±7.6%、7.1%±4.9%,P＜0.05).结论颅咽管瘤造釉细胞性较鳞状乳头型具有更强的组织炎症和细胞增殖性,可能是影响其预后的原因.     

The expression of MHC antigens on oligodendrocytes: Induction of polymorphic H-2 expression by lymphokines

Neither class I nor class II major histocompatibility complex (MHC) antigen has been demonstrated in native oligodendrocytes, the possible target of viral or immune damage in multiple sclerosis (MS). In this report, we show that H-2, but not Ia, antigen expression is induced on isolated mouse oligodendrocytes in vitro by crude supernatant from lectin-activated spleen cells, lectin-free interleukin 2, and cloned gamma-interferon. This induction of H-2 expression is not accompanied by proliferation of oligodendrocytes, whereas MHC induction in spleen cells is highly related to their proliferation, or blastoid transformation. Oligodendrocytes as well as other brain cells are probably isolated from these lymphokines by the blood-brain barrier (BBB). However, it is possible that oligodendrocytes express MHC class I antigen as a consequence of impairment of the BBB, or in the presence of activated T-cells which have been demonstrated in active MS lesions. This activation then renders oligodendrocytes possible target cells for MHC-restricted cytotoxic T-cells.     

Vimentin immunoreactivity in normal and pathological human brain tissue

Summary Vimentin immunoreactivity was examined in brain tissues from non-neurological and various human central nervous system disease cases. In all brain tissues examined, vimentin immunoreactivity was intensely positive in ependymal cells and subpial tissues, and weakly positive in some capillaries and some white matter astrocytes. In affected areas of Alzheimer's disease (AD), Pick's disease, amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS) and cerebral infarction cases, numerous intensely vimentin-immunopositive astrocytes of both protoplasmic and fibrous morphology were demonstrated. A few such astrocytes were also observed in Parkinson's disease and progressive supranuclear palsy. ALS, MS and infarction brains also had numerous, strongly vimentin-positive, round and fat-laden microglia/macrophages. In AD and ALS, a few reactive microglia with irregularly enlarged shapes were vimentin positive. In AD, they were almost exclusively related to senile plaques.Supported by grants from the Medical Research Council of Canada, and the Alzheimer Society of B. C., and donations from individual British Columbians. D. G. W. is a Research Fellow of the Alzheimer Society of B. C.     

Differential expression of Lewisx and sialyl-Lewisx antigens in fetal human neural cells in culture

Lewis^x is a cell-surface carbohydrate antigen defined by the trisaccharide structure, Galβ 1→4 (Fucα 1→3) GlcNAc. Expression of Lewis^x and sialyl-Lewis^x antigens in primary cell cultures isolated from fetal human brains of 12-15 weeks gestation was investigated by double immunolabelling with antibodies against monomeric Lewis^x (4C9), oligomeric Lewis^x (FH4), and sialylated oligomeric Lewis^x (FH6) antigens and cell type-specific markers. The monomeric Lewis^x antigen was expressed in more than 15% of astrocytes and 100% of oligodendrocytes, whereas it was not identified in neurons or in microglia. The oligomeric Lewis^x antigen was undetectable in any cell types, while the sialylated oligomeric Lewis^x antigen was expressed in more than 95% of microglia but not in any other cell types. The cell type-specific expression of Lewis^x and sialyl-Lewis^x antigens in fetal human glial cells suggests that these fucose-containing carbohydrate molecules play roles in intercellular recognition between distinct cell types during the development of the human central nervous system. © 1994 Wiley-Liss, Inc.     

Peripheral nerve injury causes transient expression of MHC class I antigens in rat motor neurons and skeletal muscles

After a peripheral nerve lesion (rat facial and sciatic) an induction of major histocompatibility complex (MHC) antigens class I was detected immunohistochemically in skeletal muscle fibers and motor neurons. This MHC expression was transient after a nerve crush, when regeneration occurred, but persisted after a nerve cut, when regeneration was prevented. Since the time course of MHC class I expression correlates to that of regeneration a role for this cell surface molecule in regeneration may be considered.     

Analysis of CD27 surface expression on T cell subsets in MS patients and control individuals

Within the peripheral blood, CD4⁺CD27⁻ T cells only reside within the CD45RAT ⁻(memory or primed) T cell subset. Cells with this phenotype have characteristics of specialized effector T cells according to their cytokine secretion profiles and the expression of tissue-specific adhesion molecules. This subset was previously found to be increased in certain diseases that are associated with immune activation. Therefore we analyzed CD27 expression of peripheral blood and CSF T cells in MS patients. Within the CD4⁺ T cell subset no differences were seen between MS patients and controls in proportions of CD45RA⁻CD27⁻ cells. However, when the CD3⁺ T cell compartment was analyzed, CD27⁻ cells were also found within the CD45RA⁺ subset. These cells, most likely CD8⁺, are significantly reduced in PBL and CSF of MS patients as compared with OND patients. In MS and OND groups the level of CD27⁻ cells in peripheral blood correlated significantly with that in CSF, indicating a balanced migration of CD27⁻ cells between the two compartments. In OIND patients, however, this equilibrium was lost. The correlation of the level of CD27⁺ cells with the amount of intrathecally produced IgG in MS patients may suggest that CD27⁺ cells are responsible for B cell help in this disease.     

Immunoreactivity of CD45, a protein phosphotyrosine phosphatase,in Alzheimer's disease

Summary Both protein kinases and phosphoprotein phosphatases are important components of signal transduction systems in cells. Recent studies in Alzheimer's disease (AD) have shown abnormal protein phosphorylation in the cortex suggesting an alteration in these enzymes. In the present study, an antibody against CD45 was used to analyze the status of this protein phosphotyrosine phosphatase in AD. We studied and quantified the immunohistochemical and immunochemical distribution of this integral membrane protein in control and AD brain. We found that anti-CD45 immunostained the great majority of microglia, both resting and activated. These cells were Ricinus communis agglutinin I positive and glial fibrillary acidic protein and neurofilament negative. The AD frontal cortex showed a 35% (P<0.01) increase in the number of anti-CD45 immunoreactive microglia as compared with controls. These results were consistent with the immunoblot quantification of CD45 immunoreactivity following native gel electrophoresis. In AD, 30% of the CD45-immunostained microglia were clustered in the neuritic plaques (about six per plaque) while the remaining 70% were scattered in the neuropil. The AD hippocampus showed an increase in CD45-immunoreactive microglia in the molecular layer of the dentte gyrus. At the ultrastructural level, CD45 immunoreactivity was localized exclusively to the plasma membrane of the microglia. The presence of the anti-CD45 immunoreactivity in microglia suggests the possibility that they may require the presence of CD45 as a cell surface receptor which may regulate cell function through modulation of intracellular signaling.Supported by National Institutes of Health grants AG08205, AG08201, and AG05131, PEW Caritable Trust, and the Alzheimer's Association/George F. Berlinger Memorial Faculty Scholar Award     

Fluorescence automatic cell sorter and immunohistochemical investigation of CD68-positive cells in meningioma

Infiltration of brain neoplasms by mononuclear cells including monocytes/macrophages has attracted little attention since they have marked morphological heterogeneity. Twenty-seven meningiomas were studied by anti-CD68 antibody-gated flow cytometry and by immunohistochemical analysis using the anti-CD68 antibodies. Flow cytometric analysis divided cells contained within tumor tissues into CD68-positive and -negative cells. In addition, eight gliomas, eight metastatic brain tumor, and 12 pituitary adenomas were investigated in the same way to compare meningiomas. The mean contents of CD68-positive cells were 24.0±3.7% in meningiomas, 4.4±1.4% in gliomas, 9.5±3.9% in metastatic brain tumors, and 4.5±1.8% in pituitary adenomas. Immunohistochemically, CD68-positive cells showed significant heterogeneity and were detected as round, rod-shaped, ameboid and ramified cells in meningiomas. Although the infiltrated mononuclear cells in gliomas have been investigated to some degree and showed that they express cytokines and/or growth factors, these infiltrated cells in meningioma have barely been studied. The CD68-positive cells detected in this study are likely to be monocytes, macrophages and microglias, and are presumed to be in various functional stages and to play important roles in growth regulation in meningioma.     

人脑胶质瘤中血管内皮生长因子表达与胶质瘤微血管数及肿瘤增殖活性关系的研究

目的　研究血管内皮生长因子 (VEGF)表达与胶质瘤微血管数、肿瘤增殖活性及其与胶质瘤恶性程度的相关性。方法　应用免疫组化方法检测 5 0例胶质瘤、8例正常脑组织中VEGF、血小板内皮细胞粘附分子 (CD3 1)和增殖细胞核抗原 (PCNA)的表达 ,测定其阳性细胞数和阳性血管数。结果　胶质瘤中均有VEGF、CD3 1及PCNA表达。其表达水平与肿瘤恶性程度呈显著正相关 ,其r分别为 0 .745 ,0 .765及 0 .685。结论　VEGF、CD3 1和PCNA在胶质瘤中的高表达是胶质瘤恶性表型之一 ,可作为病理诊断的补充。     

MHC Class II expression by human glioma cells after in vitro incubation with soluble antigens

Recent studies have suggested that astrocytes share with the macrophages several properties in vitro, among which is the ability to express MHC Class II molecules and to present some antigens to syngeneic primed lymphocytes (MHC-restricted presentation). It has been claimed in the literature that astrocytes cannot start the presentation and cannot express the related MHC Class II molecules if not previously stimulated with gamma IFN. In this paper we report that 2 human GFAP + glioma cell lines, incubated in culture with various soluble antigens for at least 24 h, were able, in the absence of gamma IFN or of activated lymphocytes, to express the MHC Class II and to expose the antigens on their surfaces. Moreover, when a lysosomotropic agent such as chloroquine was added during the incubation, no MHC Class II expression was observed. This last datum suggests that in astrocytes, as is already known in macrophages, the processing of antigens and their assembling with MHC Class II molecules probably involves the lysosomal apparatus.     

The modulation of class II histocompatibility antigens and ‘activated’ macrophage determinant in the spinal cord during the development of chronic relapsing experimental allergic encephalomyelitis (CREAE) in the guinea pig—relevance to the induction of remission?

Cryostat sections of spinal cord of guinea pigs with chronic relapsing experimental allergic encephalomyelitis (CREAE) were stained with monoclonal antibodies recognising a Strain 13-specific Ia epitope, a non-strain-specific Ia antigen and an 'activated' macrophage determinant. It was found that both Ia antigens and the 'activated' macrophage determinant, observed on infiltrating cells within both perivascular and meningeal compartments, appeared to be modulated during the course of CREAE. This correlated with the neurological symptoms of the disease. Blood vessels and 'glial' cells expressed both Ia determinants. 'Glial' cells also expressed the 'activated' macrophage antigen. These antigens were modulated with the course of the disease.     

Isolation and characterization of macrophages from scrapie-infected mouse brain

Summary We have isolated and characterized a population of brain macrophages from normal and scrapieinfected mice. The cells are phagocytic, possess Fc-IgG receptors, Mac-1 surface antigen and proliferate in the presence of macrophage colony stimulating factor. They resemble microglia in that they have a plasmalemmal distribution of the enzyme nucleoside diphosphatase, a property that is characteristic of microglia in situ. In two of the three combinations of scrapie agent and mouse strain examined, the number of brain macrophages was several fold higher than in normal control mice. The increase was not observed in mice infected intraperitoneally or in control mice inoculated with normal brain homogenate. The increase is detectable as early as 3–5 weeks postinoculation. The agent/host combination that failed to show an increase in brain macrophages is one that develops large numbers of amyloid plaques. These observations suggest that these cells are closely associated with the scrapie pathogenic process in the CNS. The failure of these cells to increase in the plaque forming model of scrapie disease also suggests that they play a role in the control of CNS amyloidogenesis.Dedicated to Prof. F. Seitelberger on the occasion of his seventieth birthdaySupported by National Institute on Aging grant no. AG04220     

Differences in cytokine gene expression profile between acute and secondary injury in adult rat spinal cord

It is likely that the environment within the injured spinal cord influences the capacity of fetal spinal cord transplants to support axonal growth. We have recently demonstrated that fetal spinal cord transplants and neurotrophin administration support axonal regeneration after spinal cord transection, and that the distance and amount of axonal growth is greater when these treatments are delayed by several weeks after injury. In this study, we sought to determine whether differences in inflammatory mediators exist between the acutely injured spinal cord and the spinal cord after a second injury and re-section, which could provide a more favorable environment for the axonal re-growth. The results of this study show a more rapid induction of transforming growth factor (TGF) beta1 mRNA expression in the re-injured spinal cord than the acutely injured spinal cord and an attenuation of proinflammatory cytokine mRNA expression. Furthermore, there was a rapid recruitment of activated microglia/macrophages in the degenerating white matter rostral and caudal to the injury but fewer within the lesion site itself. These findings suggest that the augmentation of TGFbeta-1 gene expression and the attenuation of pro-inflammatory cytokine gene expression combined with an altered distribution of activated microglia/macrophages in the re-injured spinal cord might create a more favorable milieu for transplants and axonal regrowth as compared to the acutely injured spinal cord.     

Class II MHC antigens in normal human skeletal muscle.

Class II MHC antigen expression has been investigated in muscle tissue and cultured cells from normal human skeletal muscle by light and electron immunocytochemistry. In muscle tissue, these antigens were detected in satellite cells, interstitial cells, and blood vessels. In cultures, muscle cells were stained with a pan-reactive anti-HLA class II antibody and with isotypes specific for DP, DQ, and DR. The staining was present on mononucleated cells and persisted on myotubes; it was stronger for DR and DQ isotypes than for DP. At the subcellular level, staining was located not only at the cell surface, but also next to the endoplasmic reticulum and in the cytosol. Thus, myosatellite cells and aneurally cultured cells from human normal skeletal muscle express class II MHC antigens. Moreover, the myotube staining and the presence of gold particles inside the cells suggested synthesis of these antigens after myoblast fusion.     

Possible association of human leucocyte antigen DR1 with delayed sleep phase syndrome

The study investigated the human leucocyte antigen (HLA), types A, B and DR, of 42 patients with delayed sleep phase syndrome (DSPS) and compared the frequencies of the antigens with those in 117 healthy controls. The comparison revealed that the gene frequencies and positivities of HLA-A, -B and -DR, except for DR1, had no significant differences between the patients and controls. The frequency of HLA-DR1 was increased in the DSPS patients as compared with that in the healthy controls (P = 0.0069 in positivity). Although the corrected P-value (0.069) for multiple comparisons almost reached the significance level, the results indicated a possible association of the HLA-DR1 antigen with DSPS. This study suggests that there are genetic predispositions to DSPS.