Interferon-beta treatment of experimental autoimmune encephalomyelitis leads to rapid nonapoptotic termination of T cell infiltration.

We investigated the possible mechanisms how interferon (IFN)-beta may control T cell infiltration in the CNS in experimental autoimmune encephalomyelitis (EAE). Adoptive transfer (AT) EAE was induced in groups of six female Lewis rats. Animals were treated with 3 x 10(5) units of recombinant rat IFN-beta s.c. once at 18 hr, or with 10 mg/kg methylprednisolone (MP) i.v. twice at 18 and 6 hr prior to dissection, or with a combination of both. T cell apoptosis was detected by immunohistochemistry on paraffin sections of spinal cord, using morphological criteria and TUNEL staining. Double labeling of immune cells was done for tumor necrosis factor (TNF)-alpha and metalloproteinase (MMP) 2. Disruption of the blood-brain barrier (BBB) was visualized by staining for albumin. In severe EAE, an increase of T cell apoptosis was seen after IFN-beta alone (all data presented as mean +/- SD: 24.5% +/- 2.2%, P < 0.05, vs. 19.4% +/- 3.1% in controls), and in combination with MP (29.4% +/- 7.3%, P < 0.05 vs. controls). Only the combination therapy decreased T cell infiltration (53.9 +/- 17.7 cells/mm(2), P < 0.05, vs. 99.5 +/- 35.2 cells/mm2 in controls). In moderate EAE, the rate of T cell apoptosis was slightly increased after IFN-beta (21.2% +/- 5.2% vs. 17.4% +/- 5.0% in controls), whereas MP alone (25.5% +/- 3.5%, P < 0.01 vs. controls) and the combination therapy (22.4% +/- 4.8%, P < 0.05 vs. controls) had a clear augmenting effect. IFN-beta tended to decrease T cell infiltration (46.1 +/- 12.7 cells/mm2) compared to controls (59.2 +/- 18.5 cells/mm2). The rate of TNF-alpha-expressing T cells was significantly decreased by IFN-beta and in combination with MP. Also, TNF-alpha expression in macrophages was significantly reduced by IFN-beta and by the combination therapy. The rate of MMP2-expressing macrophages was lower after IFN-beta but clearly decreased only in combination with MP. BBB disruption was ameliorated after IFN-beta but significantly only in combination with MP. Our study indicates that IFN-beta affects the immunopathological process in EAE in several ways, but apoptosis appears as a minor component. In view of treatment of MS relapses, the synergistic effects in this study corroborate the use of a combination therapy with high-dose MP and IFN-beta.     

Interleukin-12 induces mild experimental allergic encephalomyelitis following local central nervous system injury in the Lewis rat

The major pathological feature in the central nervous system (CNS) following traumatic brain injury is activation of microglia both around and distant from the injury site. Intraperitoneal administration of interleukin-12 (IL-12) after brain injury resulted in a 7% weight loss, clinical signs of mild EAE and significant myelin basic protein (MBP)-specific splenic cell proliferation. The extent of pathology, in terms of the number of inflammatory perivascular cuffs and activation of microglia was greatest if IL-12 was administered immediately compared to a week following brain injury, whether at one or two sites. Specifically immunostaining for MHC class II and iNOS on macrophages and microglia, ICAM-1 on endothelial cells and macrophages was observed around the site of injury. A degree of myelin processing was apparent from immunostaining of MBP in inflammatory cells distant from the lesion. Inflammatory cuffs comprising macrophages, activated microglia, CD4⁺ T cells and iNOS⁺ cells were also detected distant to the injury site in the medulla and spinal cord of animals treated with IL-12. These results suggest that immune-mediated events in which IL-12 production is stimulated as for example viral infection, superimposed on a brain injury, could provide a trigger for a MS-like pathology.     

The role of macrophages,perivascular cells,and microglial cells in the pathogenesis of experimental autoimmune encephalomyelitis

Clinical signs of experimental autoimmune encephalomyelitis (EAE) in rats can be suppressed by treatment with liposomes containing dichloromethylene diphosphonate (Cl₂MDP liposomes). Here we investigated whether besides the blood-borne macrophages also ED2⁺ perivascular cells and microglia are affected by this treatment. For this purpose we examined the central nervous system of bone marrow chimeras in which EAE was induced with encephalitogenic T cells. Quantification of cell numbers of various cell types in inflammatory lesions in the spinal cord showed that after treatment with Cl₂MDP liposomes more than 95% of the bone marrow derived (I1-69⁺) macrophages were eliminated. In addition the number of ED2⁺ perivascular cells were seen to be decreased by 68% as compared to ED2⁺ cells in control liposome treated animals. However the number of these perivascular cells in Cl₂MDP liposome treated animals did not differ from the number of perivascular cells in naive animals, indicating that only newly recruited, inflammation associated, ED2⁺ macrophages were eliminated. Moreover, detection of degenerating nuclei by in situ nick translation (ISNT) in combination with staining for ED1 or ED2 showed that in the perivascular space no degenerating cells were present. Cl₂MDP liposome treatment furthermore decreased the numbers of T cells infiltrating the parenchyma by more than 50%. Instead T cells were found in large numbers in the perivascular space. Microglia did not seem to be eliminated by Cl₂MDP liposome treatment as shown by the absence of ED1⁺/ISNT⁺ cells in the CNS parenchyma. However the number of ED1⁺(I1-69^?) microglial cells decreased by more than 80%, indicating that the activation of this cell type was impaired. It is concluded that bone marrow derived macrophages play an important role in the pathogenesis of EAE via interactions with lymphocytes and the activation of resident microglia. © 1995 Wiley-Liss, Inc.     

Liver X receptor activation decreases the severity of experimental autoimmune encephalomyelitis

Agonists of liver X receptors (LXR), members of the nuclear hormone receptor superfamily, alter secretion of proinflammatory cytokines, suggesting potential antiinflammatory effects. A synthetic LXR agonist inhibited T-cell proliferation and cytokine release in a dose-dependent manner. Treatment of mice during induction of experimental autoimmune encephalomyelitis reduced clinical symptoms, central nervous system cellular inflammation, and major histocompatibility class II expression on microglia, as well as demyelination. In contrast to in vitro analysis, no reductions in peripheral neuroantigen specific T-cell responses were detected in comparing ligand and vehicle treated mice. These data suggest that LXR agonists play an important protective role in the regulation of T-cell-mediated inflammatory disease of the central nervous system.     

Allograft-inflammatory factor-1 in rat experimental autoimmune encephalomyelitis,neuritis, and uveitis: Expression by activated macrophages and microglial cells

Allograft inflammatory factor-1 (AIF-1) is a Ca²⁺binding peptide expressed predominantly by activated monocytes. In order to investigate the role of AIF-1 in autoimmune lesions of the rat nervous system, we have used a synthetic gene to express AIF-1 in E.coli and have produced monoclonal antibodies against AIF-1. AIF-1 was localized to monocytes/macrophages with rather selective staining of a minor rat monocyte subpopulation of lymphoid tissue. We then investigated expression of AIF-1 in experimental autoimmune encephalomyelitis (EAE), neuritis (EAN), and uveitis (EAU). Within the local inflammatory lesions, infiltrating macrophages are prominently stained. In the diseased brain, AIF-1-positive microglial cells are not only found in the direct vicinity of the infiltrate, but widespread activation is seen in the parenchyma. This is the first demonstration that AIF-1 is present in autoimmune lesions. Immunostaining of microglial cells is noteworthy, as these cells are strategically placed regulatory elements of CNS immunosurveillance. Thus, AIF-1 might be a valuable marker to dissect the local monocyte heterogeneity in autoimmune disease. GLIA 24:244–251, 1998. © 1998 Wiley-Liss, Inc.     

Combination of cuprizone and experimental autoimmune encephalomyelitis to study inflammatory brain lesion formation and progression

Brain‐intrinsic degenerative cascades are a proposed factor driving inflammatory lesion formation in multiple sclerosis (MS) patients. We recently described a model combining noninflammatory cytodegeneration (via cuprizone) with the classic active experimental autoimmune encephalomyelitis (Cup/EAE model), which exhibits inflammatory forebrain lesions. Here, we describe the histopathological characteristics and progression of these Cup/EAE lesions. We show that inflammatory lesions develop at various topographical sites in the forebrain, including white matter tracts and cortical and subcortical grey matter areas. The lesions are characterized by focal demyelination, discontinuation of the perivascular glia limitans, focal axonal damage, and neutrophil granulocyte extravasation. Transgenic mice with enhanced green fluorescent protein‐expressing microglia and red fluorescent protein‐expressing monocytes reveal that both myeloid cell populations contribute to forebrain inflammatory infiltrates. EAE‐triggered inflammatory cerebellar lesions were augmented in mice pre‐intoxicated with cuprizone. Gene expression studies suggest roles of the chemokines Cxcl10, Ccl2, and Ccl3 in inflammatory lesion formation. Finally, follow‐up experiments in Cup/EAE mice with chronic disease revealed that forebrain, but not spinal cord, lesions undergo spontaneous reorganization and repair. This study underpins the significance of brain‐intrinsic degenerative cascades for immune cell recruitment and, in consequence, MS lesion formation.     

The proximal peripheral nervous system is a major site of demyelination in experimental autoimmune encephalomyelitis induced in the Lewis rat by a myelin basic protein-specific T cell clone

Experimental autoimmune encephalomyelitis (EAE) was induced in the Lewis rat by the passive transfer of a cytotoxic CD4⁺ T cell clone specific for the 72–89 peptide of guinea-pig myelin basic protein (MBP). Histological studies on rats with neurological signs showed that inflammation was present in the proximal peripheral nervous system (PNS), namely the spinal roots, as well as in the central nervous system (CNS). The main sites of demyelination were the spinal roots in the PNS, and the spinal cord root entry and exit zones in the CNS. The major involvement of the proximal PNS in autoimmune disease directed at MBP is in marked contrast to EAE induced by immunisation with myelin proteolipid protein, where the inflammation and demyelination are restricted to the CNS. These findings may have implications for the human inflammatory demyelinating diseases including multiple sclerosis, in which MBP is a putative target antigen.     

Protracted, relapsing and demyelinating experimental autoimmune encephalomyelitis in DA rats immunized with syngeneic spinal cord and incomplete Freund's adjuvant

Experimental autoimmune encephalomyelitis (EAE) is a model for multiple sclerosis (MS). However, MS is a chronic, relapsing and demyelinating disease, whereas EAE in rats is typically a brief and monophasic disorder showing little demyelination. We demonstrate here that DA rats develop severe, protracted and relapsing EAE (SPR-EAE) after a subcutaneous immunization at the tail base with syngeneic spinal cord and incomplete Freund's adjuvant (IFA). The neurological deficits were accompanied by demyelinating inflammatory lesions in the spinal cord, with infiltrating T lymphocytes and perivascular deposition of immunoglobulins and complement. The induction of SPR-EAE was associated with humoral autoreactivity to myelin oligodendrocyte glycoprotein (MOG) and cellular autoreactivity to the rat myelin basic protein (MBP) peptides 69–87 and 87–101. These two peptides, as well as whole rat MBP, were encephalitogenic. In conclusion, we believe that the presently described demyelinating SPR-EAE represents a useful model for MS.     

Clonal diversity of basic protein specific T cells in Lewis rats recovered from experimental autoimmune encephalomyelitis

T cell lines selected from Lewis rats recovered from experimental autoimmune encephalomyelitis (EAE) respond not only to the immunodominant 72-89 epitope of basic protein (BP), but also to secondary epitopes including the I-A restricted 43-67 region of guinea pig (Gp) BP and the I-E restricted 87-99 sequence of rat (Rt) BP. The current study demonstrates at the clonal level the diversity of T cell responses to Gp- and Rt-BP in EAE-recovered rats. As predicted from the response pattern of BP-selected T cell lines, T cell clones from the lines responded to both the dominant and secondary epitopes of BP. In addition, a new majority clonal type was identified that responded to whole BP but not to epitopes represented on enzymatic cleavage fragments or synthetic peptides spanning the BP molecule. Clones representative of each of the three types of Gp-BP responses were characterized for phenotype, major histocompatibility complex restriction, and biologic activity in vivo. All of the clones were strongly CD4+ and co-expressed CD8 at modest levels as measured by both immunofluorescence and Northern blots. All three T cell specificities were I-A restricted. However, only the 72-89 responsive clone could transfer clinical EAE, due most likely to its unique ability to respond to Rt-BP. In contrast, the Gp-BP 43-67 reactive T cell clone transferred protection against EAE, whereas the whole Gp-BP reactive clone transferred delayed-type hypersensitivity response but was neither encephalitogenic nor protective. Thus, the recovery process from EAE is distinguished by an increased diversity of protective clones as well as innocuous clones that may be spawned as encephalitogenic T cells are regulated.     

In situ demonstration of T cell activation and elimination in the peripheral nervous system during experimental autoimmune neuritis in the Lewis rat

The mechanisms of activation and termination of autoimmune responses are poorly understood. We have studied the sites and mode of activation and elimination of T cells in actively induced experimental autoimmune neuritis (EAN) and in EAN adoptively transferred by P2-specific T cells (AT-EAN). The bromodeoxyuridine (BrdU) technique was employed to detect in situ proliferating cells in spleen and sciatic nerve. We assessed the nuclear morphology of infiltrating T cells using morphological criteria of apoptotic cell death. Apoptosis of lymphoid cells was also investigated using molecular labeling techniques. In AT-EAN, the number of BrdU-positive cells in splenic germinal centers peaked at day 2 after cell transfer [554 ± 267 (mean ± SEM) per mm²; controls 98 ± 35), 1 day before disease onset, and declined thereafter. BrdU incorporation in spleens from animals with active EAN peaked at day 11, around disease onset, but reached lower total values (165 ± 29 per mm²). In neither model did we observe a significant proportion of BrdU-positive T cells in the peripheral nervous system. However, T cells exhibiting morphological signs of apoptosis were detected in the sciatic nerve immediately after disease onset. The number of these cells was highest on day 7 in AT-EAN (6.6 ± 3.2 per mm²) and on day 17 in active EAN (11.2 ± 2.2 per mm²), corresponding to the maximum of T cell infiltration in both animal models. T cell activation occurs systemically and not just in the autoimmune lesion. Infiltrating T cells are eliminated by apoptosis in situ, terminating the inflammatory process. Further insight into these mechanisms may help to develop new therapeutic strategies for autoimmune disorders of the peripheral nervous system. Received: 21 July 1995 / Revised, accepted: 31 October 1995     

Acute experimental autoimmune encephalomyelitis. Differences between T cell subsets in the blood and meningeal infiltrates in susceptible and resistant strains of guinea pigs

The percentages of early (active, high affinity-rosetting), late (total) T cells and TG cells (suppressor T cells) were determined longitudinally in the blood and meningeal infiltrating cells of Strain 13 (susceptibility) and Strain 2 (resistant) animals inoculated for acute EAE and in guinea pigs of both strains in which the disease was suppressed with myelin basic protein (MBP) in incomplete Freund's adjuvant (IFA). Reactivity of T cells to MBP and oligodendrocyte protein was tested using the antigen-reactive T cell test. After inoculation for acute EAE, a transient increase in circulating early T cells was found during the latent period in Strain 13 guinea pigs only, while both strains showed a decrease in early T cells later on. Low values of circulating TG cells were more apparent in Strain 13 than Strain 2. In infiltrating cells of the meninges, early T cell values were significantly higher in the meninges than in the blood (P less than 0.01) in Strain 13, but were only slightly elevated in Strain 2 animals. TG cell levels in meningeal infiltrates were slightly higher than corresponding blood levels in both strains. In animals which were given a suppressive regimen of MBP/IFA, circulating early T cells rose initially and showed normal values later on in both strains of guinea pigs. TG cell levels were slightly more increased in strain 13 than strain 2. In comparison to blood values, early T cells were higher in the CNS in Strain 13, and lower in the CNS in Strain 2. TG cell levels were increased over blood values in both strains. These quantitative discrepancies in T cell subset between Strain 13 and Strain 2 guinea pigs which had been inoculated for EAE might reflect a difference in the cell-mediated immune response to white matter antigens which might be related to the variation in susceptibility to EAE.     

The distribution of Ia antigen in the lesions of rat acute experimental allergic encephalomyelitis

Summary Ia antigen, encoded within the major histocompatibility complex, plays an important role in the activation of T lymphocytes. Since experimental allergic encephalitis is an essentially T cell-mediated disease, Ia antigen in the central nervous system (CNS) may be pathogenetically relevant. The occurrence of Ia antigen in the CNS of normal rats and of rats with experimental allergic encephalitis was studied by light and electron microscope immunocytochemistry using the monoclonal anti-Ia antibodies Ox 4 and Ox 6. In normal, unsensitized animals a distict population of stellate cells in the meninges and some perivascular mononuclear cells in the nervous tissue carried Ia antigen. In rats with experimental allergic encephalitis a dramatic increase of Ia-positive cells was found. In addition to the positive cells found in normal animals, monocytes, macrophages and many lymphocytes in the meningeal perivascular and parenchymal inflammatory infiltrates as well as activated microglia stained for Ia antigen. We did not find evidence for Ia expression on endothelial cells, astrocytes or other components of the CNS in either normal or diseased rats.     

Immunohistological analysis of macrophages in the central nervous system of Lewis rats with acute experimental allergic encephalomyelitis

Inflammatory cells were characterized by immunohistochemistry, utilizing monoclonal antibodies specific for T cell subsets, B cells, Ia-positive cells and cells of the mononuclear phagocyte system, in cryostat sections of central nervous system of Lewis rats, sacrificed during the course of actively induced experimental allergic encephalomyelitis. The present study provides interesting information about the presence and distribution of cells of the monocyte-macrophage lineage in this immunologically mediated disease. Using these monoclonal antibodies different subpopulations of macrophages having varying distribution patterns in the central nervous system can be recognized.     

Defective T helper cell epitope responsible for the failure of region 69-84 of the human myelin basic protein to induce experimental allergic encephalomyelitis in the Lewis rat

Studies from our laboratory have shown that region 69-84 (synthetic peptide S49S) of myelin basic protein (MBP) defines an encephalitogenic sequence for experimental allergic encephalomyelitis (EAE) in Lewis rats. The most potent EAE inducers are the guinea pig MBP (Gp-MBP) and region 69-84, known as synthetic peptide Gp-S49S: (See text: formula). Human (H-MBP) was considerably less potent than Gp-MBP, and region 69-84 (H-S49S) of H-MBP did not induce hind leg paralysis or any histological signs of EAE. Since the development of EAE requires the expression of specific T and B cell epitopes, sequence analysis of H-S49S and Gp-S49S revealed phylogenetic variations in the H-S49S sequence, characterized by positions 77 and 78, and substitution of Ser with Thr at position 80: (See text: formula). Like Gp-S49S, peptide H-S49S induced the formation of antibodies with specificities directed against the C-terminal of the H-S49S, Gp-S49S, and homologous sequences. In contrast to Gp-S49S, neither II-S49S nor shorter peptides induced clonal T cell expansion when either of the peptides was added to encephalitogenic T cell clone D in culture. Clone D, which expresses T helper phenotype, was selected from encephalitogenic peptide-primed Lewis rats. The results of the study show that the failure of H-S49S to induce EAE is related to sequence alterations in the T helper cell epitope but not in the B cell epitope located in the N- and C-terminal portions of the S49S sequence, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Treatment of relapsing autoimmune encephalomyelitis with T cell receptor Vβ-specific antibodies when proteolipid protein is the autoantigen

Monoclonal antibodies (mAbs) directed against the Vβ chain of the T cell receptor (TCR) of pathogenic T cells have been used to treat acute murine experimental autoimmune encephalomyelitis (EAE) induced by myelin basic protein (BP). We evaluated anti-Vβ mAb for the treatment of relapsing EAE (R-EAE) induced in SJL/J mice by the myelin proteolipid protein (PLP) peptide 139–151. Spinal cord mononuclear cells isolated from mice immunized for R-EAE with PLP 139–151 were shown to express a predominance of Vβ2 and Vβ17 during acute and relapsing disease. T cell lines specific for PLP 139–151 were magnetically sorted to express 80–90% Vβ2. These Vβ2-enriched lines induced typical relapsing demyelinating EAE in naive recipient mice. SJL/J mice with R-EAE induced by a PLP 139–151-specific T cell line expressing 88% Vβ2 were treated with anti-Vβ2 mAb. Anti-Vβ2 mAb markedly reduced clinical and histological disease severity when given at the time of cell transfer or when given at clinical disease onset. In contrast, anti-Vβ mAbs showed only a mild clinical effect on R-EAE induced by immunization with PLP 139–151 or R-EAE induced by immunization with PLP 139–151 or R-EAE transferred by a PLP 139–151-specific T cell line expressing multiple Vβs. A cocktail of mAbs directed against Vβ2, Vβ4, and Vβ17 significantly reduced the numbers of spinal cord T cells expressing these Vβs during acute EAE but had little effect on disease course, suggesting that pathogenic T cells expressing other Vβs were producing disease. These findings may have implications for the treatment of multiple sclerosis with Vβ-selective therapy. © 1996 Wiley-Liss, Inc.     

Multiple sclerosis: a pivotal role for the T cell in lesion development

The recognition of an increasing number of similarities between the immunologic anomalies associated with multiple sclerosis (MS) and the T cell-mediated demyelinating model, experimental autoimmune encephalomyelitis (EAE), has resulted in considerable focusing of investigative approaches. It appears that irrespective of the elucidation of the nature of the putative aetiological factor (presumed to be viral) in MS, the arrest and reversal of T cell-related events within the CNS in this devastating condition represent feasible goals and should remain a major target for some time to come. This short review summarizes the current major areas of activity as they relate to T cell involvement in the immunopathology of MS (and EAE) and presents them in the context of potential therapeutic relevance. In the light of laboratory experiments in which ablation or counteraction of the inflammatory response within the central nervous system (CNS) appears to lead to cessation of immune-mediated disease and encouragement of CNS remyelination, the prospects of similar strategies being applied to MS are becoming increasingly strong.     

Direct demonstration of the infiltration of murine central nervous system by Pgp-1/CD44 CD45RB CD4 T cells that induce experimental allergic encephalomyelitis

In experimental allergic encephalomyelitis (EAE), autoimmune T cells infiltrate the central nervous system (CNS) and initiate demyelinating pathology. We have used flow cytometry to directly analyse the migration to the CNS of MBP-reactive CD4⁺ T cells labelled with a lipophilic fluorescent dye (PKH2), in SJL/J mice with passively transferred EAE. Labelled cells constituted about 45% of the CNS CD4⁺ population at the time of EAE onset. Almost all (>90%) of the PKH2-labelled CD4⁺ T cells from EAE CNS were blasts and were α/β T cell receptor (TCR)⁺, CD44(Pgp-1)^high, and the majority were CD45RB^low. By contrast, most PKH2-labelled CD4⁺ T cells in lymph nodes, although CD44^high, were CD45RB^high cells. The cells that were transferred to induce EAE were essentially similar to antigen-primed lymph node cell populations, containing less than 15% CD44^high cells, and most of them were CD45RB^high. The CD44^high CD45RB^low phenotype is characteristic of memory/effector T cells that have been activated by antigen recognition. The difference in CD45RB expression between CNS and LN could therefore reflect differential exposure and/or response to antigen. Consistent with this, PKH2-labelled CD4⁺ cells isolated from the CNS were responsive to MBP in vitro, whereas PKH2⁺ CD4⁺ cells from lymph nodes showed almost undetectable responses. In control experiments in which ovalbumin (OVA)-reactive T cells were transferred, a small number of fluorescent-labelled CD4⁺ T cells were also detected in CNS, but there were very few blasts, and these remained CD45RB^high. These results argue for induction of the memory/effector phenotype of CD4⁺ cells, their selective retention in the CNS, as a consequence of antigen recognition.     

托法替尼对实验性自身免疫性脑脊髓炎大鼠滤泡调节性T细胞/滤泡辅助性T细胞平衡及CXCL13、转化生长因子-β1表达的影响

目的探讨托法替尼对实验性自身免疫性脑脊髓炎(EAE)大鼠滤泡调节性T细胞(Tfr)/滤泡辅助性T细胞(Tfh)平衡及CXCL13、转化生长因子-β1(TGF-β1)表达的影响。方法选择50只Wistar雌性大鼠,随机分为正常对照组、EAE对照组、托法替尼小、中、大剂量防治组,每组10只。采用髓鞘碱性蛋白及完全弗氏佐剂制造EAE模型。从造模前3 d开始EAE对照组及小、中、大剂量托法替尼防治组分别予以生理盐水和托法替尼1、2、4 mg/kg/d灌胃,连续10 d。观测大鼠发病情况、脾组织中Tfh和Tfr比例、Tfr/Tfh比值变化、脑组织匀浆中CXCL13、TGF-β1含量变化。结果EAE对照组大鼠发病潜伏期(10.20±1.99)d,托法替尼小、中、大剂量防治组发病潜伏期分别为(16.70±1.50)d、(20.20±2.44)d和(22.90±1.79)d,托法替尼各防治组发病潜伏期均较EAE对照组延长(P0.01)。EAE对照组大鼠进展期(10.50±1.84)d,托法替尼小、中、大剂量防治组发病进展期分别为(8.00±2.00)d、(5.60±1.51)d和(3.00±1.16)d,托法替尼各防治组发病进展期均较EAE对照组缩短(P0.01)。EAE对照组大鼠发病高峰期神经功能障碍评分(3.80±1.03)分,托法替尼小、中、大剂量防治组发病高峰期神经功能障碍评分分别为(2.30±1.34)分、(1.20±1.40)分和(0.60±0.84)分,托法替尼各防治组发病高峰期神经功能障碍评分均较EAE对照组降低(P0.01)。托法替尼各防治组与EAE对照组比较,Tfh细胞比例显著降低,Tfr细胞比例及Tfr/Tfh比值显著升高,CXCL13含量明显减少、TGF-β1含量明显增加,且呈剂量依赖关系,剂量越大作用越明显(P0.01;P0.05)。结论托法替尼对EAE大鼠发病具有防治作用,且呈剂量依赖关系。其防治作用机制可能与下调EAE大鼠Tfh比例及CXCL-13的表达,上调Tfr比例及TGF-1的表达,维持Tfr/Tfh平衡,并促使平衡向Tfr偏移有关。     

Localization of endothelial-monocyte-activating polypeptide II (EMAP II), a novel proinflammatory cytokine,to lesions of experimental autoimmune encephalomyelitis,neuritis and uveitis: Expression by monocytes and activated microglial cells

Endothelial-Monocyte-Activating Polypeptide II (EMAP II) is a proinflammatory cytokine and chemoattractant of macrophages. In order to investigate the role of EMAP II in autoimmune lesions of the rat nervous system, we have used a synthetic gene to express EMAP II in E. coli and have produced monoclonal antibodies against EMAP II. Monoclonal antibodies are suited to demonstrate EMAP II in ELISAs, Western blots, and paraffin-embedded tissue sections. EMAP II was localized to monocytes/macrophages with rather selective staining of a minor rat monocyte subpopulation of lymphoid tissues such as spleen, lymph nodes or follicles of the gut. In the normal brain, cells of the perivascular but not parenchymal microglia were stained. We then investigated expression of EMAP II during experimental autoimmune encephalomyelitis (EAE), neuritis (EAN), and uveitis (EAU). Within the local inflammatory lesions infiltrating macrophages are prominently stained. In the diseased brain, EMAP II-positive microglial cells are not only found in the direct vicinity of the inflammatory infiltrate, but widespread activation is seen in the parenchyma. This is the first demonstration that EMAP II is present in autoimmune lesions. Immunostaining of microglial cells is noteworthy, as these cells are strategically placed regulatory elements of CNS immunosurveillance. EMAP II might be a factor regulating monocyte chemoattraction, endothelial cell activation and a regulator of microglial cell reactivity in autoimmune inflammation of the central nervous system. GLIA 20:365–372, 1997. © 1997 Wiley-Liss, Inc.