Elispot assay detection of cytokine secretion in multiple sclerosis patients treated with interferon-beta1a or glatiramer acetate compared with untreated patients

The mechanisms behind the beneficial effects of interferon-beta1a (IFN-beta1a) and glatiramer acetate (GA) in the treatment of multiple sclerosis (MS) are still uncertain. Altered cytokine patterns have been suggested including inhibition of proinflammatory cytokines like interferon-gamma (IFN-gamma) and enhancement of anti-inflammatory cytokines such as interleukin-4 (IL-4). Twenty-nine patients with MS (10 untreated, nine treated with IFN-beta1a and 10 with GA) were investigated with elispot of peripheral blood mononuclear cells. Spontaneous and myelin induced (myelin basic protein (MBP), myelin oligodendrocyte glycoprotein (MOG)-14-39 and MOG 63-87) IFN-gamma, IL-4, IL-5 and IL-10 secretion was studied. We found a significant reduction of spontaneous IFN-gamma, IL-4 and IL-5, but no difference in IL-10 secreting cells in both groups of treated patients compared with the untreated patients. Myelin-specific responses showed a significant decrease of IFN-gamma and an increase of IL-5, but no change in IL-4 and IL-10 secreting cells in treated compared with untreated patients. Both treatment groups revealed similar cytokine secretion patterns except for a more pronounced decrease of both spontaneous and MOG 14-39 induced IL-4 secretion in the IFN-beta1a treated group. Thus, immunological effects of IFN-beta1a and GA were similar showing that disease promoting Th1 (IFN-gamma) cells were reduced while the potentially beneficial Th2 response (IL-4) was maintained.     

Th1, Th2 and Th3 cytokine alteration in schizophrenia

BACKGROUND: Several studies have shown that there is an imbalance between T helper 1 (Th1) cytokines and T helper 2 (Th2) cytokines in patients with schizophrenia. The T helper 3 (Th3) cytokine, transforming growth factor beta-1 (TGF-beta1), has been shown to suppress the production of Th1 cytokines. Therefore it is hypothesized that it may play a role in schizophrenia by suppressing overactive Th1 system. METHODS: We recruited 88 schizophrenic patients and 88 matched controls. The basal plasma concentrations of IFN-gamma (Th1), IL-4 (Th2) and TGF-beta1 (Th3) were studied at the time the patients were admitted to the hospital and following 8 weeks of treatment with antipsychotics. RESULTS: The detection rate of plasma IFN-gamma and basal plasma TGF-beta1 level were significantly higher in schizophrenic patients than in controls whereas detection rate of plasma IL-4 was lower in patients. The ratio of Th1/Th2 cytokines (IFN-gamma/IL-4) was higher in schizophrenic patients. Following the neuroleptic treatment, the IFNgamma and TGF-beta1 levels returned to control values, and IL-4 concentration rose above the control value. CONCLUSION: Schizophrenic patients showed higher Th1/Th2 ratio which is attenuated by effective neuroleptic treatment. It is possible that TGF-beta1 plays a role in reducing the activity of Th1 cytokine.     

Multiple sclerosis is associated with high levels of circulating dendritic cells secreting pro-inflammatory cytokines.

Recent evidence emphasises a pivotal role for dendritic cells (DC) in the control of immunity by priming and tolerising T cells. DC capture and process antigens, express co-stimulatory molecules, migrate to lymphoid organs and secrete cytokines to initiate immune responses. In multiple sclerosis (MS), autoreactive T cells are proposed to play a pathogenic role by secreting pro-inflammatory cytokines, but studies on DC are lacking. To evaluate the involvement of DC in patients with MS, a modified procedure was used to prepare DC from blood of patients with MS and healthy subjects. DC were found to be potent stimulators of T cells in allogeneic and, to a lesser extent, in autologous mixed leukocyte reaction (MLR). Enzyme-linked immunospot (ELISPOT) assays were adopted to determine levels of IFN-gamma, TNF-alpha, IL-6 and IL-10 secreting DC vs. mononuclear cells (MNC). Proportionally more DC than MNC secreted IFN-gamma and IL-10 in both MS and healthy subjects. Patients with MS had higher levels of IFN-gamma, TNF-alpha and IL-6 secreting DC than healthy subjects. The differences for IFN-gamma and TNF-alpha secreting cells were confined to the subgroup of untreated MS patients and not observed in the subgroup examined during ongoing treatment with IFN-beta. Circulating DC secreting pro-inflammatory cytokines may represent another focus for the study of both immuno-pathogenesis and therapeutic interventions in MS.     

Mechanisms of immunomodulation by glatiramer acetate

OBJECTIVE: To define the mechanism of action of glatiramer acetate (GA; formerly known as copolymer-1) as an immunomodulatory treatment for MS. BACKGROUND: The proposed mechanisms of action of GA include 1) functional inhibition of myelin-reactive T cells by human leukocyte antigen (HLA) blocking, 2) T-cell receptor (TCR) antagonism, and 3) induction of T helper 2 (Th2) immunomodulatory cells. In this report, the authors examined the effects of GA on the functional activation of human T-cell clones (TCC) specific for myelin basic protein (MBP) and for foreign antigens. Several questions were addressed: Is the inhibitory effect of GA specific for autoantigens? Is it mediated by blocking the interaction between peptide and HLA molecule? Is GA a partial agonist or TCR antagonist, or does it induce anergy? Does it induce Th2 modulatory T cells? METHODS: The effects of GA on antigen-induced activation of human TCC specific for MBP, influenza virus hemagglutinin, and Borrelia burgdorferi were studied by proliferation and cytokine measurements, TCR downmodulation, and anergy assays. GA-specific TCC were generated in vitro from the peripheral blood of patients and healthy controls by limiting dilution. RESULTS: GA more strongly inhibited the proliferation of MBP, as compared with foreign antigen-specific TCC; in some MBP-specific TCC, the production of Th1-type cytokines was preferentially inhibited. In addition to HLA competition, the induction of anergy, but not direct TCR antagonism, was observed. Numerous GA-specific TCC were generated from the peripheral blood of both MS patients and normal controls, and a fraction of these showed a Th2 phenotype. CONCLUSIONS: This study confirms a preferential inhibitory effect of GA on autoreactive TCC. With respect to cellular mechanisms, although HLA competition appears to play the most important role in functional inhibition in vitro, a direct effect on the TCR may be involved at least in some autoreactive T cells as shown by anergy induction. Although not confirmed at the clonal level, it is demonstrated further that GA induces T cells that crossreact with myelin proteins. GA-specific, Th2-modulatory cells may play an important role in mediating the effect of the drug in vivo.     

Differential effects of phosphodiesterase type 4-specific inhibition on human autoreactive myelin-specific T cell clones.

Proinflammatory cytokines, secreted by autoreactive CD4+ T lymphocytes may contribute to the pathogenesis of several human autoimmune diseases, including multiple sclerosis (MS). Since the antigen specificities of these T cells are not known at present, therapeutic strategies aiming at common effector pathways, in particular cytokine secretion, may be more feasible in the near future. We have studied the influence of the isoenzyme-specific phosphodiesterase inhibitor rolipram on the proliferation and cytokine secretion of human myelin basic protein-specific T cell clones. The inhibition of proliferation correlated with interference with the IL-2/IL-2 receptor system, while the effects of rolipram on several T helper 1-(TNF-alpha, TNF-beta, IFN-gamma) and T helper 2-like cytokines (IL-4, IL-13) as well as IL-10 revealed an interesting drug profile, with preferential inhibition of TNF-beta, TNF-alpha and IL-10. This profile suggest that rolipram differs from other currently used immunomodulatory drugs.     

Glatiramer acetate (GA) induces IL-13/IL-5 secretion in naive T cells

In order to define possible mechanisms of immunomodulation by glatiramer acetate (GA), we investigated the primary in vitro cytokine response of peripheral blood mononuclear cells (PBMCs) and T-cell subpopulations. In PBMCs from healthy subjects and untreated patients with multiple sclerosis (MS) GA-induced T-cell proliferation and mRNA expression/cytokine, secretion of IL-13 and IL-5 but not of IL-10, TGF-beta or IL-12, IL-4 was detected at the mRNA level only. IFN-gamma was induced in a few subjects at very low concentrations. The response to GA was driven by the CD4(+)/CD45RA(+) T-cell subpopulation and was mediated by T-cell receptor (TCR) engagement as determined by anti-TCR blocking antibodies. The findings are compatible with the hypothesis that GA functions as partial or weak TCR-agonist activating naive T cells to produce the Th2 cytokines IL-13 and IL-5.     

IFN-beta1a and IFN-beta1b have different patterns of influence on cytokines

Multiple sclerosis is characterized by elevated levels of proinflammatory cytokines produced by Th1 cells and decreased levels of anti-inflammatory cytokines produced by Th2 cells. IFN-beta treatment shifts the immune response from the Th1 to Th2 pattern, thus enhancing the production of anti-inflammatory Th2 cytokines such as IL-4, IL-10, and decreasing the production of proinflammatory Th1 cytokines such as IFN-gamma. To determine which IFN-beta has the stronger immunomodulatory effect we compared the levels of IL-4, IL-10, and IFN-gamma of 12 relapsing-remiting MS patients treated with IFN-beta1b (Betaferon) with those of 10 patients treated with IFN-beta1a (Avonex). There were no statistically significant differences in duration of disease, number of relapses before and during treatment, and in EDSS after 2 years of treatment. After 1 year of treatment the concentration of IFN-gamma was significantly lower in the Betaferon group, and concentrations of IL-4 and IL-10 were significantly higher in the Avonex group. It appears that IFN-beta1b has a downregulatory effect on both Th1 and Th2 cytokines, while IFN-beta1a causes a shift of the cytokine profile toward the Th2 phenotype. These two IFN have different influences on the pattern of cytokines in MS: IFN-beta1a enhances the production of anti-inflammatory cytokines IL-4 and IL-10 and IFN-beta1b decreases the production of the proinflammatory cytokine IFN-gamma.     

Characterization of T cell lines derived from glatiramer-acetate-treated multiple sclerosis patients

We analyzed the effects of glatiramer acetate (GA) therapy on in vitro proliferative responses and cytokine production by lymphocytes derived from multiple sclerosis patients receiving this therapy. We confirmed that lymphocytes derived from GA na?ve patients show a high frequency of response when initially exposed to GA in vitro; this frequency decreased following GA therapy. The frequency of lymphocytes responding to whole MBP stimulation did not change with GA therapy. GA- and MBP-specific T cell lines generated from these patients by repeated cycles of in vitro stimulation did not cross react. Some (23%) whole MBP-reactive T cell lines did cross react with MBP peptide 83-99. The mean levels of interferon (IFN) gamma secretion and the mean ratio of IFN-gamma/IL-5 were lower for GA-reactive cell lines, derived from patients both prior to and during GA therapy, compared to MBP-reactive T cell lines. The proportion of IFN-gamma(+) cells in unfractionated lymphocyte preparations derived from the GA-treated patients did not differ from that found for healthy controls. Our findings indicate that GA-reactive T cell lines derived from GA-treated MS patients continue to show a relative Th2 cytokine bias consistent with a bystander suppressor function. GA treatment is not associated with a cytokine phenotype shift in the total T cell or MBP-reactive T cell populations.     

Interferon-beta regulates cytokines and BDNF: greater effect in relapsing than in progressive multiple sclerosis

The mechanism of action of interferon (IFN)-beta therapy in multiple sclerosis (MS) is only partially known, and its efficacy changes with disease stage. In different forms of MS, we determined how IFN-beta regulates mononuclear cell production of the important anti-inflammatory Th2 cytokine - IL-10, the Th1 cytokine - IFN-gamma, and the brain-derived neurotrophic protein - BDNF. Activated T cells and monocytes from therapy-na?ve patients secreted more IL-10 than healthy controls. During IFN-beta therapy, however, T cells produced less IL-10. In vitro, IFN-beta stimulated IL-10 production by activated T cells, but inhibited IL-10 secretion by activated monocytes, a richer source of IL-10 than T cells. The form of MS also affected cytokine production. IL-10 and BDNF levels in MNC were high during relapsing/remitting (RR) MS, but low in progressive MS. Surprisingly, IFN-beta therapy increased BDNF levels in antidepressant-na?ve patients, but BDNF was lower during concurrent antidepressant drug therapy, suggesting an interaction between MS, depression, and neurodegeneration. IFN-beta in vitro strongly induced IL-10 and IFN-gamma in activated T cells in RRMS, but not in progressive MS, suggesting IFN resistance. IFN-beta effects are specific for disease state and immune subsets, possibly explaining why IFN-beta therapy is most effective in early T cell-regulated RRMS, but less beneficial in progressive MS, where chronic plaques contain few T cells and high numbers of monocytes.     

Functional properties of myelin oligodendrocyte glycoprotein-reactive T cells in multiple sclerosis patients and controls

Autoimmune T-cell reactivity to myelin components may be implicated in the initiation or maintenance of the inflammation leading to myelin destruction in multiple sclerosis (MS). Myelin oligodendrocyte glycoprotein (MOG), a quantitatively minor myelin protein, is an important candidate autoantigen in MS. We studied T-cell responses to recombinant MOG (extracellular domain, rMOG) and a panel of four peptides within this domain (amino acids 1-22, 34-56, 64-86 and 74-96) in MS patients and healthy controls (NS). Frequency analysis of T cells reactive to rMOG as measured by IFN-gamma ELISPOT did not reveal significant differences between MS patients and controls. MOG-reactive T-cell lines and clones (TCL/TCC) were generated by stimulating PBMC of four MS patients and three healthy subjects with a cocktail of the four MOG peptides. The functional properties of 50 MOG peptide-reactive TCL/TCC obtained were studied. All TCL were TCR alpha beta+CD4+ and 20 TCL showed reactivity to MOG peptides 1-22, 13 to 34-56, 1 to 64-86 and 16 to 74-96. No significant differences in peptide recognition were observed between MS patients and controls. The T-cell receptor (TCR) hypervariable regions of MOG-reactive TCL/TCC showed a heterogeneous usage of various TCR V(-D)-J elements. The data provide no evidence for clonal expansions within the MOG-reactive T-cell repertoire of the two study groups. Intracellular cytokine analysis demonstrated predominantly Th1-TCC (IFN-gamma+/IL-4-) in MS patients, while most MOG-reactive TCC of control subjects had a mixed Th0/Th1 phenotype. Furthermore, the MS-derived MOG-reactive TCC produced increased levels of TNF-alpha upon antigen stimulation as compared to controls. Most of the MS-derived MOG-TCC induced specific cytolysis of autologous MOG-pulsed PBMC (9/11) while none of the MOG-TCC isolated from control subjects showed this cytotoxicity (0/8). In conclusion, although the frequency of anti-MOG T cells was similar in MS patients and controls, our data indicate potential differences in the functional properties of MOG TCL in MS patients versus healthy controls which may relate to their role in the disease process.     

Impaired interleukin-12 production in multiple sclerosis patients.

Multiple Sclerosis (MS), a disease of the human central nervous system, is believed to be a T cell mediated autoimmune disorder with genetic and environmental influences. Interleukin-12 (IL-12), a proinflammatory cytokine produced primarily by antigen presenting cells is a potent inducer of interferon-gamma (IFN-gamma) and other Th1 cytokines that may play an important role in MS pathogenesis. We have investigated IL-12 production induced by the T cell independent pathway in untreated and IFN-beta treated MS patients, healthy individuals and other neurological disease (OND) patients in response to the human pathogen Staphylococcus aureus. We report that peripheral blood mononuclear cells (PBMC) from untreated MS patients produce normal amounts of the biologically active IL-12 p70 heterodimer but significantly less free IL-12 p40 heavy chain than PBMC from both healthy and disease controls when challenged in vitro with Staphylococcus aureus. Both mRNA expression of the inducible IL-12 p40 chain and protein levels were found to be reduced in untreated MS patients. No decrease in the production of the IL-12 p40 was seen in MS patients on IFN-beta therapy. The decreased production of IL-12 p40 heavy chain is not attributed to increased IL-10 secretion, a defect in the production of cytokines by macrophages or the number of cytokine producing cells. The factor(s) responsible for the decrease in p40 remain to be determined. Since IL-12 p40 antagonizes the biological activity of IL-12 in vitro and in vivo, identification of a defect in the 'natural' antagonist of IL-12, may provide the basis for immune therapy.     

Tc1/Tc2 and Th1/Th2 balance in Asian and Western types of multiple sclerosis, HTLV-I-associated myelopathy/tropical spastic paraparesis and hyperIgEaemic myelitis

CD8+ T cells, like CD4+ T cells, can differentiate into at least two subsets with distinct cytokine patterns: Tc1 cells produce Th1-like cytokines and Tc2 cells produce Th2-like cytokines. To clarify the immunopathological roles of Tc1 and Tc2 cells in central nervous system (CNS) inflammation, we examined intracellular cytokines in CD8+ and CD4+ T cells by flow cytometry and analyzed the Tc1/Tc2 balance as well as the Th1/Th2 balance in 80 patients with various CNS inflammatory diseases, including 20 with optico-spinal multiple sclerosis (OS-MS), 21 with conventional MS (C-MS), 22 with human T-lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and 17 with hyperIgEaemic myelitis. Twenty-two healthy subjects were also examined as controls. Patients with OS-MS showed a significantly higher percentage of INF-gamma+IL-4- CD8+ T cells as well as CD4+ T cells and a significantly higher intracellular interferon-gamma (IFN-gamma)/interleukin-4 (IL-4) ratio both in CD8+ and CD4+ T cells throughout the relapse and remission phases than the healthy controls. Furthermore, the patients with OS-MS showed a significantly lower percentage of INF-gamma-IL-4+ CD4+ T cells as well as CD8+ T cells during the relapse phase than the healthy controls. On the other hand, the patients with C-MS showed a significantly higher percentage of IFN-gamma-IL-4+ CD8+ T cells in addition to more IFN-gamma+IL-4- CD4+ T cells during the relapse phase than the healthy controls. The HAM/TSP patients showed a significantly higher percentage of INF-gamma+IL-4- CD8+ T cells and a significantly higher intracellular IFN-gamma/IL-4 ratio in CD8+ T cells than the healthy controls. In contrast, in hyperIgEaemic myelitis, in addition to a significantly lower intracellular IFN-gamma/IL-4 ratio in CD4+ T cells, a tendency toward a lower intracellular IFN-gamma/IL-4 ratio in CD8+ T cells in comparison to the healthy controls was observed. These results clarified for the first time the distinct Tc1/Tc2 balance in each disease condition as follows: Tc1 cell response is predominant in OS-MS and HAM/TSP, while Tc2 cell response is predominant in hyperIgEaemic myelitis and at relapse phase of C-MS. Furthermore, our results suggest that CD8+ T cells play an adjunctive role in disease induction and the clinical course of MS.     

Glatiramer acetate induces a Th2-biased response and crossreactivity with myelin basic protein in patients with MS

Glatiromer acetate (GA) is an approved treatment for multiple sclerosis (MS). The proposed mechanism of action is the induction of GA-specific T cells characterized by protective anti-inflammatory Th2 response. We tested this hypothesis in 11 MS patients treated with GA from 1-19 months. Interferon-gamma and IL-5 (markers of Th1 and Th2 responses respectively) were assayed by ELISA in GA-specific T-cell lines (TCL) supernatants. Th1/Th2 bias was defined based on the ratio of IFN-gamma/IL-5 secretion. Fifty-eight pre-treatment and 75 on-treatment GA-specific TCL were generated. On-treatment mean IL-5 levels in GA-TCL increased significantly, whereas those for IFN-gamma were markedly reduced. Consequently, the ratio of IFN-gamma IL-5 also shifted in favor of a Th2 response. The percentage of GA-TCL classified as Th1 was decreased, whereas those classified as Th2 increased on-treatment as compared to pre-treatment. Some GA-specific TCL, (approximately 25%) generated during treatment secreted predominantly IL-5 in response to MBP and the immunodominant MBP peptide 83-99, indicating that these crossreactive antigens can act as partial agonists for GA-reactive TCL. These results strongly suggest that the mechanism of action of GA in MS involves the induction of crossreactive GA-specific T cells with a predominant Th2 cytokine profile.     

Chemokine receptor expression on MBP-reactive T cells: CXCR6 is a marker of IFNgamma-producing effector cells

Cytokine-polarized T cells have distinct chemokine receptor (CKR) expression patterns associated with their cytokine secretion profiles. In order to investigate this paradigm in autoreactive human T cells, we have determined the CKR expression pattern of myelin basic protein (MBP)-reactive T cell lines (TCL) and compared these profiles to those of TCL-generated in response to tetanus toxoid (TT). Expression of CXCR6 and CXCR3 on TCL was significantly positively correlated with IFNgamma, and inversely correlated with IL-5 production. TT TCL had significantly higher expression of CCR7(-)/CD45RA(-) T effector memory (Tem) cells than MBP TCL. However, in MBP-specific TCL, CXCR6 was found to be the best marker of conversion to the Tem phenotype. CXCR6 and CXCR3 are likely to be important in the migration of effector memory T cells in Th1-mediated inflammatory diseases such as multiple sclerosis (MS).     

Cytokine imbalance in the pathophysiology of major depressive disorder

OBJECTIVE: A substantial body of evidence indicates that dysregulation of the immune system is associated with Major Depressive Disorder (MDD). Because most cytokines have pleiotropic effects, we measured various subsets of cytokines to examine the association between immune response and MDD. METHODS: Forty-eight hospitalized MDD patients and 63 normal controls were recruited. We measured in vitro monocytic (IL-6 and tumor necrosis factor (TNF)-alpha), Th1 (interferon (IFN)-gamma and interleukin (IL)-2), Th2 (IL-4), and Treg (transforming growth factor (TGF)-beta1) cytokine production as well as IL-2/IL-4 and IFN-gamma/IL-4 ratios for both groups. Depressive symptoms were assessed by Hamilton Depression Rating Scale. Patients were evaluated before and after 6 weeks of antidepressant treatment. RESULTS: At admission, IL-6, TNF-alpha, TGF-beta1 production, and IFN-gamma/IL-4 ratio were significantly higher, whereas IFN-gamma, IL-2, and IL-4 were significantly lower in MDD patients. After treatment, IL-6 and TGF-beta1 production were significantly lower than before treatment. CONCLUSION: We suggest that activation of monocytic proinflammatory cytokines, and inhibition of both Th1 and Th2 cytokines may be associated with immunological dysregulation in MDD. TGF-beta1 may be associated with the regulation of monocytic cytokines as well as Th1 and Th2 cytokines in MDD.     

Differences in cytokines between non-suicidal patients and suicidal patients in major depression

Several studies have shown that there is an imbalance between pro-inflammatory and anti-inflammatory cytokines in major depressive disorder (MDD). However, little is known about the role of cytokines in suicide. In the present study, amounts of IL-6, IL-2, IFN-gamma, IL-4, and TGF-beta1 produced by mitogen-stimulated whole blood were measured in 36 MDD patients who had recently attempted suicide, 33 non-suicidal MDD patients, and 40 normal controls. The severity of depression symptoms and suicidal behaviors was evaluated using Hamilton's depression rating scale (HDRS), the Lethality Suicide Attempt Rating Scale (LSARS), and the Risk-Rescue Rating (RRR). Non-suicidal MDD patients had significantly higher IL-6 production than suicidal MDD patients and normal controls (p<0.001). Suicidal MDD patients had significantly lower IL-2 compared with non-suicidal patients and normal controls (p<0.001). Both MDD groups, with or without attempted suicide, had significantly lower IFN-gamma and IL-4 and higher TGF-beta1 production. HDRS scores had significant positive correlations with IL-6, IFN-gamma, and the Th1/Th2 ratio and significant negative correlations with IL-4 in non-suicidal depression patients (p<0.005); however, these correlations did not hold true for suicidal patients. Suicidal MDD patients had no significant correlations between the LSARS or RRR scores and cytokine release. Our findings suggest that the immune response has distinct differences between non-suicidal patients and suicidal patients. Non-suicidal MDD may be associated with increased IL-6 production and a Th1/Th2 imbalance with a shift to Th1, while suicidal MDD may be associated with decreased IL-2.     

Diminished frequency of interleukin-10-secreting, T-cell receptor peptide-reactive T cells in multiple sclerosis patients might allow expansion of activated memory T cells bearing the cognate BV gene

T cells responsive to T-cell receptor (TCR) determinants may regulate pathogenic Th1 responses in patients with multiple sclerosis (MS) through interleukin (IL)-10-dependent bystander suppression. In this study, innate IL-10- and interferon (IFN)-gamma-secreting T cells responsive to TCR peptides were quantified in peripheral blood mononuclear cells of MS patients and healthy controls (HC) using the ELISPOT assay. Most HC had vigorous IL-10 but low IFN-gamma frequencies to BV5S2 and BV6S1 peptides. In contrast, MS patients had significantly lower IL-10 frequency responses to the TCR peptides but normal responses to concanavalin A. Patients undergoing TCR-peptide vaccination had moderate responses that fluctuated in concert with vaccination. In an MS patient and HC, expression of BV6S1 by activated memory T cells was inversely associated with the presence of IL-10-secreting BV6S1-reactive T cells. These results suggest that MS patients have diminished frequencies of innate TCR-reactive T cells that may allow oligoclonal expansion of activated autoreactive Th1 effector cells expressing cognate V genes.     

The effects of interferon-β on interleukin-10 in multiple sclerosis patients

The incidence of the neuropathological lesions and the severity of the clinical symptoms in multiple sclerosis (MS) are correlated with the amount of the transferred autoreactive T cells. The balance between the T helper 1 (Th1) and T helper 2 (Th2) cytokine phenotypes may affect the activity of the disease in MS patients. Interleukin-10 (IL-10) is a cytokine secreted by Th2 cells. Thus, it has been thought that inducing IL-10 may have therapeutic effects in the treatment of MS patients. In this study, in order determine whether different types of prophylaxis change the secretion of IL-10, we measured the levels of IL-10 in relapsing-remitting type multiple sclerosis (RRMS) patients receiving interferon-beta 1b (IFN-beta 1b) or azathioprine (AZA). Our study consisted of RRMS patients (n=45) and healthy subjects (n=15) as control group. Patients were categorized into three groups as those receiving either IFN-beta 1b or AZA and those not receiving prophylaxis. Each group was compared with the control group. Serum IL-10 levels were determined using ELISA method. IL-10 levels of those receiving IFN-beta 1b were found to be significantly higher than that of other groups. These results support that the ability of inducing anti-inflammatory cytokine IL-10 plays a role in the clinical advantage of IFN-beta 1b in MS treatment.     

Expression of cytokines and cytokine receptors in human Schwann cells

The expression of cytokines and cytokine receptors was investigated in enriched populations of human fetal Schwann cells by reverse transcribed-PCR and enzyme-linked immunosorbent assay. Human fetal Schwann cells constitutively expressed mRNA of IL-1beta, IL-6, IL-8, IL-11, IL-12, IL-15 and TGF-beta, and also cytokine receptors for IL-1, IL-4, IL-6, IL-8, IL-13, tissue necrosis factor and gp130. The expression of IL-1beta, IL-6 and IL-15 was upregulated following treatment with IL-1beta or TGF-beta. The protein levels of IL-6 were increased with IL-1beta treatment, but were decreased with IFN-gamma treatment. Human Schwann cells may respond to cytokine signals in the nerve injury sites and modify the pathological conditions by secreting cytokines. The secreted cytokines may play a role in leukocyte recruitment and exacerbation of axonal injury process.