Decreased CD3-mediated interferon-γ production in relapsing-remitting multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system that has been postulated to be T-cell mediated. We examined the proliferation and cytokine secretion of mononuclear cells after stimulation with OKT3 (anti-CD3) monoclonal antibody concanavalin A, or ionomycin plus myristic acid palmityl ester in subjects with stable relapsing-remitting MS. Control subjects demonstrated good proliferation to anti-CD3 monoclonal antibody whereas subjects with relapsing-remitting MS showed a significantly decreased anti-CD3 monoclonal antibody-mediated response. There was no difference in concanavalin or ionomycin plus myristic acid palmityl ester stimulation between control subjects and MS subjects. Secretion of interferon-γ was significantly decreased and transforming growth factor-β was significantly increased from cultures stimulated with anti-CD3 monoclonal antibody, but not ionomycin plus myristic acid palmityl ester or concanavalin A, in MS patients compared to control subjects. Secretion of interleukin-10 and tumor necrosis factor-β was not different between control subjects and MS patients following stimulation with anti-CD3 monoclonal antibody, concanavalin A, or ionomycin plus myristic acid palmityl ester, or of interleukin-2 and interleukin-4 following stimulation with anti-CD3 monoclonal antibody or concanavalin A. An abnormality of signal transduction and secretion of the immunomodulatory molecule interferon-γ may exist in MS via the CD3 T-cell receptor complex.     

Evaluation of interleukin 10 and interferon-α in the cerebrospinal fluid and serum of patients with multiple sclerosis

The activities of IL-10, a cytokine produced by TH2 cells, monocytes and B-cells, and IFN-α, a product of activated macrophages/monocytes, were investigated in the CSF and serum samples of 25 subjects with clinically definite multiple sclerosis (MS), of whom 14 were in the active and nine in the stable phase, and of 15 controls with other noninflammatory neurological diseases (OND). Elevated CSF IL-10 and IFN-α levels were found in MS patients in the stable phase with respect to patients in the active phase (p > 0.001), while no significant differences were observed in the mean serum levels between MS patients (both in the active and stable phase) and controls. Finally, a significant correlation was detected between IL-10 and IFN-α in the CSF of MS patients in remission. This study suggests that IL-10 may downregulate MS progression.     

Seasonal variation of interferon-γ production in progressive multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system. There is increased interferon (IFN)-γ secretion in MS patients in vitro, and IFN-γ administration induces exacerbations of disease suggesting a link between IFN-γ and disease activity. We observed significantly increased IFN-γ production in the autumn and winter months compared with the spring and summer months in chronic progressive MS, and this increase was linked to endogenous interleukin (IL)-12 production. Increased seasonal IFN-γ was not observed in normal control subjects, and there were no seasonal changes in IL-10 in progressive MS. These results suggest a potential environmental link between dysregulated IFN-γ production and MS disease progression and pathogenesis.     

Increased transforming growth factor-β, interleukin-4, and interferon-γ in multiple sclerosis

The inflammatory nature of multiple sclerosis (MS) implicates the participation of immunoregulatory cytokines, including the T-helper type 1 (Th1) cell–associated interferon-σ (IFN-σ), the Th2 cell–related interleukin-4 (IL-4), and the immune response–downregulating cytokine transforming growth factor-β (TGF-β), but proof for their involvement in MS has been lacking. By adopting in situ hybridization with complementary DNA oligonucleotide probes for human IFN- IL-4, and TGF-β, the expression of mRNA for these cytokines was detected in mononuclear cells (MNC) from blood and cerebrospinal fluids. Strongly elevated levels of MNC expressing all three cytokines were found in peripheral blood and at even higher frequencies in cerebrospinal fluid from untreated patients with MS and optic neuritis, i.e., a common first manifestation of MS, compared with patients with other neurological diseases and healthy subjects. In MS and optic neuritis, IL-4 mRNA expressing cells predominated, followed by TGF-β– and IFN-σ–positive cells. Control patients with myasthenia gravis had similarly elevated levels of IFN-σ and TGF-β mRNA expressing blood MNC but lower numbers of IL-4–positive cells. No or slight disability of MS was associated with high levels of TGF-β mRNA expressing cells, while MS patients with moderate or severe disability had high levels of IFN-σ–positive cells. IFN-σ and TGF-β may have opposing effects in MS, and treatments inhibiting IFN-σ and/or promoting TGF-β might ameliorate MS.     

Magnetic resonance imaging results of the PRISMS trial: A randomized,double-blind,placebo-controlled study of interferon-β1a in relapsing-remitting multiple sclerosis

The PRISMS (Prevention of Relapses and Disability by Interferon-β1a Subcutaneously in Multiple Sclerosis) trial was a double-blind, randomized, multicenter, phase III, placebo-controlled study of interferon-β1a in 560 patients from 22 centers in 9 countries with clinically definite or laboratory-supported relapsing-remitting multiple sclerosis. The patients were randomized to receive recombinant interferon-β1a (Rebif), 22 μg (6 mIU), 44 μg (12 mIU), or placebo, given subcutaneously, three times weekly for 2 years. All patients underwent biannual proton density/T2-weighted magnetic resonance imaging scans to determine the overall magnetic resonance imaging disease activity and burden of disease, and a cohort of 205 patients had 11 initial monthly proton density/T2-weighted and gadolinium-enhanced/T1-weighted magnetic resonance imaging scans. Over the 2 years, the placebo group showed a progressive median increase in burden of disease of 10.9%, whereas the 22-μg group and 44-μg group showed median decreases of 1.2% and 3.8%, respectively. The number of T2 active lesions and percentage of scans showing T2 activity on the biannual scans were also significantly reduced in both treatment groups compared with placebo, with a clear dose–effect favoring the 44-μg dose over the 22-μg dose. In the subgroup undergoing initial monthly scanning, this reduction in activity became statistically significant 2 months after the start of treatment. These results provide strong, objective evidence to support the positive clinical results of reduction in relapses and delay in disease progression. In addition, they also demonstrate a significant dosage effect, favoring the 44-μg dose. Ann Neurol 1999;46:197–206     

Incidence of exacerbations in the first 90 days of treatment with recombinant human interferon β-1b in patients with relapsing-remitting multiple sclerosis

Interferon β-1b (IFNβ1B) is effective in reducing the frequency of exacerbations in patients with relapsing-remitting multiple sclerosis (RRMS). Recently, a study suggested that treatment with IFNβ-1b may place MS patients at risk of exacerbations by increasing interfreon-β (IFNγ) sereting cells in the blood early after onset of treatment. We conducted a retrospective study in 192 RRMS patients treated with IFNβ-1b. We did not observe an increase in the frequency of exacerbations early after the onset of treatment and suggest that the IFNγ-secreting cell surge linked to the onset of treatment with IFNβ-1b may not be clinically significant.     

Tumor necrosis factor-α messenger RNA expression in patients with relapsing-remitting multiple sclerosis is associated with disease activity

We determined the cytokine messenger RNA (mRNA) expression pattern of blood mononuclear cells in 29 patients with relapsing-remitting multiple sclerosis every 4 weeks over a period of 12 months. During this period 27 relapses occurred in 14 patients (48%). Progression of disease activity as assessed by the occurrence of new lesions on nonenhancing T2-weighted magnetic resonance images of the head was detected in 12 (48%) of 25 patients. Using a semiquantitative polymerase chain reaction we demonstrated significant increases in tumor necrosis factor-α mRNA expression in peripheral blood mononuclear cells prior to a relapse. In 24 (85%) of 27 relapses increased tumor necrosis factor-α mRNA expression preceded clinical symptoms by 4 weeks. A similar pattern was observed for lymphotoxin mRNA expression. At the same time, transforming growth factor-β and interleukin-10 mRNA levels declined. Fluctuations in the mRNA expression of tumor necrosis factor-αwere also observed in 6 patients with stable disease who had active magnetic resonance scans on follow-up. No correlation of disease activity was observed with interleukin-1β, -4, or -6, inferferon gamma or endothelin-1 mRNA expression. From these data it can be concluded that variations in cytokine mRNA expression in blood mononuclear cells are correlated with disease activity in relapsing-remitting multiple sclerosis. It may be a valuable parameter to monitor the immunological status of patients in future clinical trials.     

RANTES production and expression is reduced in relapsing-remitting multiple sclerosis patients treated with interferon-beta-1b

RANTES (regulated upon activation, normal T-cell expressed and secreted), a CC chemokine, appears to play a role in the pathogenesis of relapsing-remitting multiple sclerosis (RR-MS), enhancing the inflammatory response within the nervous system. We have demonstrated that RANTES production is increased in RR-MS compared to controls. Interferon-beta-1b (IFN-beta-1b) treatment reduces RANTES production in sera and peripheral blood adherent mononuclear cell (PBAM) supernatants both in relapse and remission. IFN-beta-1b also reduces RANTES expression in PBAM. Our results suggest that RANTES modulation might represent one of the mechanisms of action of IFN-beta-1b in RR-MS.     

Interferon-γ secretion by peripheral blood T-cell subsets in multiple sclerosis: Correlation with disease phase and interferon-β therapy

Interferon-γ (IFN-γ) is implicated as a participant in the immune effector and regulatory mechanisms considered to mediate the pathogenesis of multiple sclerosis (MS). We have used an intracellular cytokine staining technique to demonstrate that the proportion of ex vivo peripheral blood CD4 and CD8 T-cell subsets expressing IFN-γ is increased in secondary progressing (SP) MS patients, whereas the values in untreated relapsing-remitting (RR) MS patients are reduced compared with those of controls. Patients treated with interferon-β (IFN-β) have an even more significant reduction in the percentage of IFN-γ–secreting cells. The finding that the number of IFN-γ–expressing CD8 cells is increased in SPMS patients, a group with reduced functional suppressor activity, and is most significantly reduced by IFN-β therapy, which increases suppressor activity, indicates that IFN-γ secretion by CD8 T cells and functional suppressor defects attributed to this cell subset in MS can be dissociated. Ann Neurol 1999;45:247–250     

Cognitive dysfunction in patients with relapsing-remitting multiple sclerosis

Cognitive dysfunction is considered one of the clinical markers of multiple sclerosis (MS). However, in the literature there are inconsistent reports on the prevalence of cognitive dysfunction, and separate data for the relapsing-remitting (RR) type of the disease are not always presented. In this study, we submitted 461 RRMS patients to a battery of neuropsychological tests to investigate their impairment in various cognitive domains. As a consequence of the exclusion criteria, the sample is not fully representative of the entire population of RRMS patients. In this selected sample, when only the eight scores of a core battery (Mental Deterioration Battery) were considered (with respective cutoffs), it emerged that 31% of the patients were affected by some degree of cognitive deficit. In particular, 15% had mild, 11.2% moderate and 4.8% had severe impairment. Information processing speed was the most frequently impaired area, followed by memory. When two other tests (SDMT and MCST) were added and cognitive domains were considered, it emerged that 39.3% of the patients were impaired in two or more domains. When four subgroups were obtained by means of cluster analysis and then compared, it emerged that information processing speed and memory deficits differentiated the still cognitively unimpaired from the mildly impaired MS patients. Significant associations were found between cognitive and clinical characteristics. However, due to the large sample size, clinically irrelevant relationships may also have emerged. Even with the limitations imposed by the sample selection and the possible underestimation of the prevalence and severity of cognitive dysfunction, these results seem to provide further evidence that information processing speed deficit may be an early and important marker of cognitive impairment in MS patients.     

Determination of interferon-γ in the peripheral blood of multiple sclerosis patients in remission, using a chemiluminescence technique

The plasma from eight patients with multiple sclerosis (MS) whose disease was in remission, was investigated by a chemiluminescence technique for its ability to stimulate the oxidate metabolism of peripheral blood monocytes (PBM). The active fraction identified had a molecular weight between 13 700 and 43 000 Da. Its activity was reduced by incubation at pH 2, pH 4 or pH 6, or by treatment at 56°C for 1–3 h. The activity was also decreased, 58–100%, by prior incubation with antibodies to human interferon-γ (IFN-γ). We suggest that these results indicate that the increased chemiluminescence activity (CL-A) of PBM in MS patients in remission is due mainly to the presence of circulating IFN-γ.     

Longitudinal analyses of the effects of neutralizing antibodies on interferon beta-1b in relapsing-remitting multiple sclerosis

We have analysed data on exacerbation rates, Expanded Disability Status Scale (EDSS) scores, and lesion burdens using the results of two neutralizing antibody (NAB) assays (CPE and MxA) from the pivotal relapsing-remitting multiple sclerosis (MS) trial of interferon beta-1b (IFNB) with a longitudinal approach, where the influence of NABs in individual patients is assessed by comparing responses during NAB-positive and NAB-negative periods. There are apparent influences on exacerbation rate related to dose of IFNB, titer level, and duration of positivity. With the MxA assay, exacerbation rates after switching to NAB-positive status are estimated to be 28% higher [95% confidence interval (CI): (-15%, 92%)] and -2% higher [95% CI: (-21%, 21%)] on the low- and high-dose IFNB arms, respectively. When compared with all NAB-negative periods, exacerbation rates during NAB-positive periods are estimated to be 29% higher [95% CI: (0%, 67%)] and 18% higher [95% CI: (0%, 40%)] on the low- and high-dose IFNB arms, respectively. When NAB-positive patients again become NAB-negative, no evidence of increased exacerbation rates could then be demonstrated. More detailed exploratory analyses indicate that the effects are most evident in the approximately 20% of patients developing high titers. In these patients, the influence of NABs may be self-limited, as titers often diminish or NABs become undetectable with time.     

Interferon beta-1b modulates MCP-1 expression and production in relapsing-remitting multiple sclerosis

Monocyte chemoattractant protein-1 (MCP-1) seems to be involved in the pathogenesis of multiple sclerosis (MS). We found that in unstimulated (PHA(-)) and PHA-stimulated (PHA(+)) peripheral blood mononuclear cells (PBMC), MCP-1 and TNFalpha levels are higher in stable untreated MS patients. Interferon gamma (IFNgamma) is higher in relapsing patients in PHA(-) cultures and in stable patients in PHA(+) cultures. Chronic IFNbeta-1b treatment down-regulates TNFalpha, IFNgamma and MCP-1 production except for TNFalpha in relapsing patients. IFNbeta-1b, in vitro, increases MCP-1, TNFalpha and IFNgamma spontaneous production in all patients. Multivariate analysis suggests that MCP-1 production is dependent from clinical status and not from TNFalpha and IFNgamma production. Logistic regression analysis shows that MCP-1 production is significantly modified by treatment. Further studies are needed to clarify the role of MCP-1 in MS.     

Nociceptive R3 reflex in relapsing-remitting multiple sclerosis patients.

Pain in multiple sclerosis (MS) patients has only recently been recognised as a genuine symptom of this disease. It is important to determine whether this pain is the consequence of another symptom of MS or whether it is due to a demyelinating lesion affecting pain pathways. A close relationship has been found between the R3 component of the blink reflex and the pain threshold. The aim of this work was to carry out an objective evaluation of the nociceptive system in MS patients by means of the R3 component of the blink reflex. The study was performed on 20 healthy volunteers and on 20 clinically defined relapsing-remitting MS patients with EDSS not > 3.5, normal R1 and R2 components of the blink-reflex, personal and family anamnesis negative for migraine and trigeminal neuralgia; the patients were not taking drugs at the time of the test. A significant difference was found, between healthy volunteers and patients, for R3 threshold, pain threshold and R3 latency.     

Cytokine profile in interferon-β treated multiple sclerosis patients: reduction of interleukin-10 mRNA expressing cells in peripheral blood

Treatment with interferon-β reduces relapse rate, slows progression of neurological disability and reduces the number of active brain lesions observed with magnetic resonance imaging in relapsing-remitting multiple sclerosis. Interferon-β has antiviral properties, but in addition it affects the expression of several immunoregulatory genes, including genes for cytokines such as interferon-γ and interleukin-10. Cytokines are believed to be central in the pathologic process in multiple sclerosis, by regulating autoreactive T- and B-cell responses. In this study we have determined effects of interferon-β on the frequency of cells in peripheral blood and cerebrospinal fluid expressing mRNA for interferon-γ, tumor necrosis factor-α, interleukin-4 and interleukin-10 in a group of multiple sclerosis patients. All patients were treated for two months or more, since the beneficial effect of interferon-β is not apparent until after several months of treatment. We detected a significant reduction of interleukin-10 mRNA expressing cells in the peripheral blood during interferon-β treatment compared with pretreatment values (10 vs 33 cells/10⁵; p = 0.028) while the other investigated cytokines were not significantly affected. We conclude that there is a long term effect of interferon-β on cytokine expression in multiple sclerosis patients. Its relation to the therapeutic effect is as yet not clear.     

Mitoxantrone treatment in patients with early relapsing-remitting multiple sclerosis

We investigated the clinical and MRI effects of mitoxantrone (MITOX) administered to 45 patients during the first five years of highly active relapsing-remitting multiple sclerosis. Differences occurring between the end of treatment and follow-up (clinical mean: 3.6 years; brain MR: 1.8 years) with respect to baseline variables (EDSS, annualized relapse rate, active T2 lesions, new T1 lesions and number of Gd-enhancing lesions) were analysed using parametric and non-parametric tests. One patient developed leukemia four months after the end of the treatment; no other serious adverse events occurred during treatment and the follow-up period. A clinically relevant reduction in the annualized relapse rate ( P < 0.0001 at end of treatment and P < 0.0001 at follow-up) and improvement in the EDSS (P < 0.0001 at end of treatment and P = 0.0005 at follow-up) was found. At the end of treatment, 53% of patients experienced no increase in active T2 lesions, while 73% showed no increase in the number of new T1 lesions. At follow-up, 41 out of 45 (91%) patients showed a stable MRI pattern and were active-scan free. Despite potential serious adverse events, MITOX may be considered an option in selected patients with very active early MS.