Xueqiang Hu

Interleukin-17-secreting T cells in neuromyelitis optica and multiple sclerosis during relapse

Growing evidence suggests that interleukin (IL)-17 and IL-17-secreting CD4(+)T (Th17) cells are involved in the pathogenic mechanisms of multiple sclerosis (MS). IL-17-secreting CD8(+)T cells were recently identified as a novel subset of CD8(+)T cells. We aimed to analyze the role of Th17 and IL-17 secreting CD8(+)T cells in the pathogenesis of neuromyelitis optica (NMO) as well as MS. Fourteen patients with NMO, 20 with MS and 16 control participants (CTL) were enrolled between November 2008 and December 2009. The proportion of Th17 cells and IL-17 secreting CD8(+)T cells were counted using flow cytometry, and serum levels of IL-6, IL-17, IL-21, IL-23, and transforming growth factor-beta (TGF-β) were measured by enzyme-linked immunosorbent assay. Patients with NMO had a larger proportion of Th17 cells than patients with MS (3.72% versus [vs.] 2.58%, p=0.02) and CTL (3.72% vs. 1.36%, p<0.001). The proportion of Th17 cells in patients with MS was also markedly higher than in the CTL (2.58% vs. 1.36%, p<0.001). IL-17-secreting CD8(+)T cell counts in NMO patients were markedly higher than in MS patients (1.61% vs. 1.09%, p=0.036) and CTLs (1.61% vs. 0.58%, p<0.001). The proportion of IL-17-secreting CD8(+)T cells in MS patients was also higher than in CTLs (1.09% vs. 0.58%, p=0.002). Serum IL-17 and IL-23 levels were increased in patients with NMO and MS, while serum IL-21 concentration was higher only in NMO patients compared to CTL. We concluded that Th17 cells were highly activated in patients with NMO. IL-17-secreting CD8(+)T cells were increased in patients with NMO and MS during relapse and have an important role in the pathological mechanism of NMO and MS.

Overexpression of CNTF in Mesenchymal Stem Cells reduces demyelination and induces clinical recovery in experimental autoimmune encephalomyelitis mice

Human Mesenchymal Stem Cells (MSCs) were previously reported to ameliorate neuronal functional deficits in the MOG35-55-induced experimental autoimmune encephalomyelitis (EAE) mice by inducing T cell anergy. Human Ciliary neurotrophic factor (CNTF) recently was found to promote myelogenesis and reduce inflammation in CNTF-deficient EAE mice. We ectopically overexpressed CNTF in human MSCs to investigate its potential role in promoting remyelination and improving functional recovery in EAE mice. MSCs transfected by Ad-CNTF-IRES-EGFP (MSC-CNTF) were injected intravenously into EAE mice 10 days after the immunization. Neurological functional tests were scored daily by grading clinical signs (score 0-6). Immunofluorescence microscopy was used to detect MSC-CNTF in spinal cord. Expression of NG2, CNTF, and cleaved caspase-3 was measured by immunohistochemistry. CNTF expression was also analyzed by Western blot. Myelin was detected by Solochrome Cyanin staining. Our results found that CNTF concentration in MSC-CNTF cells was 20-fold higher than that in either MSC or Ad-EGFP-transfected MSCs (MSC-EGFP) in vitro. Mice receiving MSC-CNTF cells showed remarkable neuronal functional recovery: the cumulative clinical scores were significantly decreased, and the disease onset was statistically delayed. Mice receiving MSC-CNTF cells showed reduced TNF-alpha, IFN-gamma and increased the level of cytokine IL-10 in peripheral blood and a large number of MSC-CNTF cells were detected in the spleen, but were not detected in other organs such as lung, liver and kidney. In the lesions of these mice, 1) the number of cleaved caspase3-positive cells was significantly reduced; 2) MSC-CNTF- and NG2-positive cells were significantly increased; and 3) the expression of CNTF was dramatically increased. In addition, demyelination was significantly reduced in MSC-CNTF mice. These data indicated that MSC-CNTF may improve functional recovery in EAE mice, possibly by exerting their immunoregulatory activity, inhibiting inflammation, homing MSC-CNTF cells to the lesions, elevating CNTF expression, reducing demyelination, and stimulating oligodendrogenesis.

Soluble egg antigen from Schistosoma japonicum modulates the progression of chronic progressive experimental autoimmune encephalomyelitis via Th2-shift response

Soluble egg antigen (SEA) is strongly antigenic and inherently induces Th2-biased immune responses. In this study, we tested whether SEA from Schistosoma japonicum is able to prevent experimental autoimmune encephalomyelitis (EAE) induced by MOG(35-55) peptide, an established animal model of multiple sclerosis (MS). Intraperitoneal administration with SEA before EAE induction and in the preclinical phase after EAE induction successfully ameliorated the severity and progression of EAE on mice compared with phosphate buffered saline (PBS) controls, while no protective effect was shown when SEA immunization began after disease onset. This effect was associated with reduced interferon gamma (IFN-gamma) production and/or increased interleukin 4 (IL-4) production in spleen and central nervous system (CNS) even at the chronic stage. Similarly, we observed reduced inflammation and demyelination in spinal cords of SEA pretreated EAE mice compared with controls. Our data indicate that immunization with SEA from S. japonicum induces a preestablished Th2-biased microenvironment that provides preventive immune-modulating effects on EAE progression. This study may have important implications for its promising therapeutic use in MS and other autoimmune diseases.

Increased memory Th17 cells in patients with neuromyelitis optica and multiple sclerosis

OBJECT To investigate the clinical relevance of memory Th17 cells in patients with neuromyelitis optica (NMO) or multiple sclerosis (MS). PATIENTS AND METHODS The proportion of peripheral memory Th17 cells was determined by flow cytometry. Sera IL-17A and IL-23 levels were detected by ELISA kits. RESULTS Memory Th17 proportion and IL-17A level were much higher in patients with NMO or MS and were related to clinical features. After high-dose intravenous methylprednisolone (IVMP) therapy, memory Th17 proportion and IL-17A and IL-23 levels were decreased. CONCLUSIONS Memory Th17 is related to the development and relapse of NMO and MS, and IVMP can inhibit memory Th17.

Comparative Brain Stem Lesions on MRI of Acute Disseminated Encephalomyelitis, Neuromyelitis Optica, and Multiple Sclerosis

Background Brain stem lesions are common in patients with acute disseminated encephalomyelitis (ADEM), neuromyelitis optica (NMO), and multiple sclerosis (MS). Objectives To investigate comparative brain stem lesions on magnetic resonance imaging (MRI) among adult patients with ADEM, NMO, and MS. Methods Sixty-five adult patients with ADEM (n = 17), NMO (n = 23), and MS (n = 25) who had brain stem lesions on MRI were enrolled. Morphological features of brain stem lesions among these diseases were assessed. Results Patients with ADEM had a higher frequency of midbrain lesions than did patients with NMO (94.1% vs. 17.4%, P<0.001) and MS (94.1% vs. 40.0%, P<0.001); patients with NMO had a lower frequency of pons lesions than did patients with MS (34.8% vs. 84.0%, P<0.001) and ADEM (34.8% vs. 70.6%, P = 0.025); and patients with NMO had a higher frequency of medulla oblongata lesions than did patients with ADEM (91.3% vs. 35.3%, P<0.001) and MS (91.3% vs. 36.0%, P<0.001). On the axial section of the brain stem, the majority (82.4%) of patients with ADEM showed lesions on the ventral part; the brain stem lesions in patients with NMO were typically located in the dorsal part (91.3%); and lesions in patients with MS were found in both the ventral (44.0%) and dorsal (56.0%) parts. The lesions in patients with ADEM (100%) and NMO (91.3%) had poorly defined margins, while lesions of patients with MS (76.0%) had well defined margins. Brain stem lesions in patients with ADEM were usually bilateral and symmetrical (82.4%), while lesions in patients with NMO (87.0%) and MS (92.0%) were asymmetrical or unilateral. Conclusions Brain stem lesions showed various morphological features among adult patients with ADEM, NMO, and MS. The different lesion locations may be helpful in distinguishing these diseases.

HLA-DPB1 0501 is associated with susceptibility to anti-aquaporin-4 antibodies positive neuromyelitis optica in southern Han Chinese.

OBJECTIVES To analyze the role of HLA-DRB1 and -DPB1 alleles in the pathogenesis of neuromyelitis optica (NMO) and multiple sclerosis in Southern Han Chinese. METHODS Thirty serum anti-aquaporin 4 antibodies (AQP4-Ab)-positive NMO patients, 53 conventional multiple sclerosis (C-MS) patients, and 93 controls (CTLs) were enrolled. The HLA-DRB1 and -DPB1 alleles of the subjects were determined by sequencing-based typing (SBT). RESULTS The frequency of the DRB1 0901 was lower in NMO patients than in CTLs (P(uncorr)=0.022, OR: 0.194, 95% CI: 0.043-0.876), and DRB1 1602 was higher in NMO patients than in C-MS (P(uncorr)=0.038, OR: 3.491, 95% CI: 1.024-11.896) and CTLs (P(uncorr)=0.051, OR: 2.711, 95% CI: 0.971-7.556). The frequency of DPB1 0501 was significant higher in NMO patients than in C-MS (P(uncorr)=0.018, OR: 4.629, 95% CI: 1.235-17.350) and CTLs (P(uncorr)=0.001, P(corr)=0.022, OR: 7.096, 95% CI: 2.011-25.044). CONCLUSIONS DPB1 0501 correlates with risk of AQP4-Ab positive NMO in Southern Han Chinese.

Serum uric acid levels of patients with multiple sclerosis and other neurological diseases

The serum uric acid (UA) levels were measured in 112 patients with multiple sclerosis (MS) and 794 patients with different types of other neurological diseases (OND) or healthy control group. Serum UA levels, along with relevant clinical parameters of MS and OND, were also investigated. MS patients had significantly lower UA levels than those with transient ischemia attack (344.6 130.6 μmol/L, P 0.000), cerebral hemorrhage (311.9 104.7 μmol/L, P 0.000), cerebral infarction (291.3 101.6 μmol/L, P 0.014) and the healthy control group (312.1 92.8 μmol/L, P 0.000). MS patients had significantly higher serum UA levels than those with cryptococcus meningitis or meningoencephalitis (178.9 107.0 μmol/L, P 0.000) and tuberculous meningitis or meningoencephalitis patients (175.7 99.9 μmol/L, P 0.000). There were no significant differences in UA levels between patients with MS and those with facial neuritis, viral meningitis or encephalitis, pulmonary tuberculosis, polymyositis or dermatomyositis, myasthenia gravis, subarachnoid hemorrhage, migraine, Guillain–Barre syndrome and myelitis. In addition, UA levels were independently correlated with gender and duration of MS, but neither with MRI activity, disability nor subtypes of the disease in MS patients. Our data suggest that UA has two biphasic functions: neuroprotective and injurious. Our studies may help physicians to deal with conditions having abnormal UA levels. Multiple Sclerosis 2008; 14: 188–196. http://msj.sagepub.comThe serum uric acid (UA) levels were measured in 112 patients with multiple sclerosis (MS) and 794 patients with different types of other neurological diseases (OND) or healthy control group. Serum UA levels, along with relevant clinical parameters of MS and OND, were also investigated. MS patients had significantly lower UA levels than those with transient ischemia attack (344.6 +/- 130.6 micromol/L, P = 0.000), cerebral hemorrhage (311.9 +/- 104.7 micromol/L, P = 0.000), cerebral infarction (291.3 +/- 101.6 micromol/L, P = 0.014) and the healthy control group (312.1 +/- 92.8 micromol/L, P = 0.000). MS patients had significantly higher serum UA levels than those with cryptococcus meningitis or meningoencephalitis (178.9 +/- 107.0 micromol/L, P = 0.000) and tuberculous meningitis or meningoencephalitis patients (175.7 +/- 99.9 micromol/L, P = 0.000). There were no significant differences in UA levels between patients with MS and those with facial neuritis, viral meningitis or encephalitis, pulmonary tuberculosis, polymyositis or dermatomyositis, myasthenia gravis, subarachnoid hemorrhage, migraine, Guillain-Barre syndrome and myelitis. In addition, UA levels were independently correlated with gender and duration of MS, but neither with MRI activity, disability nor subtypes of the disease in MS patients. Our data suggest that UA has two biphasic functions: neuroprotective and injurious. Our studies may help physicians to deal with conditions having abnormal UA levels.

IL-22 secreting CD4 + T cells in the patients with neuromyelitis optica and multiple sclerosis

Interleukin (IL)-22 secreting CD4(+) T (Th22) cells and IL-22 are involved in the pathogenesis of autoimmune disease, but their role in neuromyelitis optica (NMO) and multiple sclerosis (MS) is unclear. We measured the proportion of Th22, Th17, CD4(+)IL-22(+)IL-17A(+) T cells and serum IL-22 in NMO and MS patients. The proportion of Th22 cells, Th17 cells and serum IL-22 were increased in patients with NMO and MS. Our findings suggest that increased Th22 cells may play an important role in the pathogenesis of NMO and MS.

Attenuation of experimental autoimmune encephalomyelitis in C57 BL/6 mice by osthole, a natural coumarin

Osthole, a natural coumarin, is known to have a variety of pharmacological and biochemical uses and is considered to have potential therapeutic applications. Here we examined the effects of osthole on the central nervous system demyelination in experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis and its mechanism(s). C57 BL/6 mice immunized with myelin oligodendrocyte glycoprotein 35-55 amino acid peptide were treated with osthole at day 7 post immunization (7 p.i., subclinical periods, early osthole treatment) and day 13 p.i. (clinical periods, late osthole treatment) respectively and both therapies continued throughout the study. The content of nerve growth factor (NGF) and interferon gamma (IFN-gamma) in the sera and brain of mice in vivo as well as the splenocytes culture supernatants in vitro were detected. The results showed that osthole retarded the disease process when the therapy was initiated at subclinical periods, attenuated the clinical severity of EAE mice when the therapy was initiated at both subclinical and clinical periods, ameliorated inflammation and demyelination and improved the outcomes of magnetic resonance imaging. In addition, osthole blocked the reduction of NGF and suppressed IFN-gamma increase in EAE mice. These results suggested that osthole might be a new pharmacological approach to treat multiple sclerosis.

Artemisinin attenuates lipopolysaccharide-stimulated proinflammatory responses by inhibiting NF-κB pathway in microglia cells.

Microglial activation plays an important role in neuroinflammation, which contributes to neuronal damage, and inhibition of microglial activation may have therapeutic benefits that could alleviate the progression of neurodegeneration. Recent studies have indicated that the antimalarial agent artemisinin has the ability to inhibit NF-κB activation. In this study, the inhibitory effects of artemisinin on the production of proinflammatory mediators were investigated in lipopolysaccharide (LPS)-stimulated primary microglia. Our results show that artemisinin significantly inhibited LPS-induced production of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1) and nitric oxide (NO). Artemisinin significantly decreased both the mRNA and the protein levels of these pro-inflammatory cytokines and inducible nitric oxide synthase (iNOS) and increased the protein levels of IκB-α, which forms a cytoplasmic inactive complex with the p65-p50 heterodimeric complex. Artemisinin treatment significantly inhibited basal and LPS-induced migration of BV-2 microglia. Electrophoretic mobility shift assays revealed increased NF-κB binding activity in LPS-stimulated primary microglia, and this increase could be prevented by artemisinin. The inhibitory effects of artemisinin on LPS-stimulated microglia were blocked after IκB-α was silenced with IκB-α siRNA. Our results suggest that artemisinin is able to inhibit neuroinflammation by interfering with NF-κB signaling. The data provide direct evidence of the potential application of artemisinin for the treatment of neuroinflammatory diseases.