Changes in plasma cytokines induced by interferon-beta1a treatment in patients with multiple sclerosis

Exosomal biomarkers in Down syndrome and Alzheimer's disease

Every person with Down syndrome (DS) has the characteristic features of Alzheimer's disease (AD) neuropathology in their brain by the age of forty, and most go on to develop AD dementia. Since people with DS show highly variable levels of baseline function, it is often difficult to identify early signs of dementia in this population. The discovery of blood biomarkers predictive of dementia onset and/or progression in DS is critical for developing effective clinical diagnostics. Our recent studies show that neuron-derived exosomes, which are small extracellular vesicles secreted by most cells in the body, contain elevated levels of amyloid-beta peptides and phosphorylated-Tau that could indicate a preclinical AD phase in people with DS starting in childhood. We also found that the relative levels of these biomarkers were altered following dementia onset. Exosome release and signaling are dependent on cellular redox homeostasis as well as on inflammatory processes, and exosomes may be involved in the immune response, suggesting a dual role as both triggers of inflammation in the brain and propagators of inflammatory signals between brain regions. Based on recently reported connections between inflammatory processes and exosome release, the elevated neuroinflammatory state observed in people with DS may affect exosomal AD biomarkers. Herein, we discuss findings from studies of people with DS, people with DS and AD (DS-AD), and mouse models of DS showing new connections between neuroinflammatory pathways, oxidative stress, exosomes, and exosome-mediated signaling, which may inform future AD diagnostics, preventions, and treatments in the DS population as well as in the general population.

Genetic, Immune-Inflammatory, and Oxidative Stress Biomarkers as Predictors for Disability and Disease Progression in Multiple Sclerosis

The aim of this study was to evaluate the TNFβ NcoI polymorphism (rs909253) and immune-inflammatory, oxidative, and nitrosative stress (IO&NS) biomarkers as predictors of disease progression in multiple sclerosis (MS). We included 212 MS patients (150 female, 62 male, mean (±standard deviation (SD)) age = 42.7 ± 13.8 years) and 249 healthy controls (177 female, 72 male, 36.8 ± 11 years). The disability was measured the Expanded Disability Status Scale (EDSS) in 2006 and 2011. We determined the TNFβ NcoI polymorphism and serum levels of interleukin (IL)-6, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, IL-4, IL-10, and IL-17, albumin, ferritin, and plasma levels of lipid hydroperoxides (CL-LOOH), carbonyl protein, advanced oxidation protein products (AOPPs), nitric oxide metabolites (NOx), and total radical-trapping antioxidant parameter (TRAP). The mean EDSS (±SD) in 2006 was 1.62 ± 2.01 and in 2011 3.16 ± 2.29, and disease duration was 7.34 ± 7.0 years. IL-10, TNF-α, IFN-γ, AOPP, and NOx levels were significantly higher and IL-4 lower in MS patients with a higher 2011 EDSS scores (≥3) as compared with those with EDSS < 3. The actual increases in EDSS from 2006 to 2011 were positively associated with TNF-α and IFN-γ. Increased IFN-γ values were associated with higher pyramidal symptoms and increased IL-6 with sensitive symptoms. Increased carbonyl protein and IL-10 but lowered albumin levels predicted cerebellar symptoms. The TNFB1/B2 genotype decreased risk towards progression of pyramidal symptoms. Treatments with IFN-β and glatiramer acetate significantly reduced TNF-α but did not affect the other IO&NS biomarkers or disease progression. Taken together, IO&NS biomarkers and NcoI TNFβ genotypes predict high disability in MS and are associated with different aspects of disease progression. New drugs to treat MS should also target oxidative stress pathways.

Chemokine network in multiple sclerosis: role in pathogenesis and targeting for future treatments

Multiple sclerosis is the most common inflammatory disorder of the CNS. Evidence suggests that an immunomediated mechanism plays a crucial role during the development of the disease. Currently, two classes of immunomodulatory agents -- interferon-beta and glatiramer acetate (Copaxone, Teva Pharmaceutical Industries), have been approved for the long-term treatment of multiple sclerosis. New drugs which effectively target the immunological processes occurring in multiple sclerosis have been proposed. This review summarizes the immunological background that occurs during the pathogenesis of multiple sclerosis focusing on chemokines and related receptors. The effects of standard treatments on the immune system are analyzed along with the current knowledge of potential new immunomodulatory molecules, such as antiadhesion molecules, statins, estriol, cannabinoids, neurotrophic factors and chemokine antagonists.

Cytokine profile in relapsing‑remitting multiple sclerosis patients and the association between progression and activity of the disease

Multiple sclerosis (MS) is a progressive immune‑ mediated disease caused by demyelination of the central nervous system. Cytokines and their receptors have an important role in the evolution of MS lesions, and pro‑ and anti‑inflammatory cytokine levels have been found to correlate with changes in MS disease activity. The aims of the present study were to evaluate the pro‑inflammatory [tumor necrosis factor (TNF)‑α and interleukin (IL) ‑1β, ‑6 and ‑12], T helper (Th) 1 [interferon (IFN)‑γ], Th17 (IL‑17) and Th2 (IL‑4 and ‑10) cytokine serum levels in relapsing‑remitting (RR)‑MS patients and to evaluate the association between the cytokine profile and the progression and activity of the disease. Serum cytokine levels were assessed using enzyme linked‑immunosorbent assays in 169 RR‑MS patients in the remission clinical phase and 132 healthy individuals who were age‑, gender‑, ethnicity‑ and body mass index‑matched. Disability and activity of the disease were evaluated using the Expanded Disability Status Scale and magnetic resonance imaging with gadolinium, respectively. IFN‑γ and IL‑6, ‑12 and ‑4 levels were higher in RR‑MS patients compared to controls (P=0.0009, 0.0114, 0.0297 and 0.0004, respectively). IL‑1 levels were higher in controls compared with RR‑MS patients. IL‑4 levels were higher in RR‑MS patients with mild disability compared to those with moderate and severe disability (P=0.0375). TNF‑α and IL‑10 levels were higher in RR‑MS patients with inactive disease compared with those with active disease. IL‑17 levels showed a trend towards being higher in RR‑MS patients with inactive disease compared to those with active disease (P=0.0631). Low TNF‑α and high IFN‑γ levels were independently associated with RR‑MS (P=0.0078 and 0.0056, respectively) and also with the activity of the disease (P=0.0348 and 0.0133, respectively). Results indicated that RR‑MS patients, even in the remission clinical phase, exhibit a complex system of inflammatory and anti‑inflammatory cytokines that may interact to modulate the progression and activity of the disease.

Interleukin-10 and interleukin-12 modulation in patients with relapsing-remitting multiple sclerosis on therapy with interferon-beta 1a: differences in responders and non responders

We examined the effects of interferon (IFN)beta-1a on interleukin (IL)-12p70 and IL-10 secretion in 27 Relapsing Remitting Multiple Sclerosis (RRMS) patients, divided in responders and non-responders. In responders, IFNbeta-1a does not change the IL-12p70 concentrations, but it leads to a remarkable increase in the IL-10 production. Besides, a high IL-10/IL-12 ratio is demonstrated during the first six months of therapy. In non-responders, there were not significant alterations in the cytokine profile. We suggest that IFNbeta-1a effect in RRMS patients could be explained by its modifying effect on cytokine pattern. Moreover, we propose a possible role of IL-10/IL-12 ratio as a serum marker predictive of favorable clinical course.

Natalizumab treatment in multiple sclerosis: marked decline of chemokines and cytokines in cerebrospinal fluid

Natalizumab exerts impressive therapeutic effects in patients with multiple sclerosis (MS). The proposed main mode of action is reducing transmigration of leukocytes into the CNS, but other immunological effects may also be operative. Cytokines and chemokines are involved in the regulation of inflammatory responses and may reflect the disease process in MS. The objective of this study was to evaluate the effects of natalizumab treatment on cytokine and chemokine profiles systemically and intrathecally in multiple sclerosis. We used luminex to analyse a panel of cytokines (IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, TNF-alpha, IFN-gamma, GM-CSF) and chemokines (CXCL9, CXCL10, CXCL11, CCL17, CCL22) in blood and cerebrospinal fluid (CSF) from 31 patients with relapsing MS before and after one year of natalizumab treatment. There was a marked decline in CSF levels of cytokines and chemokines, thus including pro-inflammatory cytokines (IL-1beta, IL-6 and IL-8) as well as chemokines associated with both Th1 (CXCL9, CXCL10, CXCL11) and Th2 (CCL22). Circulating plasma levels of some cytokines (GM-CSF, TNF-alpha, IL-6 and IL-10) also decreased after one year of treatment. This is the first study to show that natalizumab treatment is associated with a global decline in cytokine and chemokine levels at a protein level. This finding was most pronounced in CSF, in line with the reduced transmigration of cells into CNS, whereas reduction in plasma levels indicates other possible mechanisms of natalizumab treatment.

Cytokine responses to acute and chronic exercise in multiple sclerosis

Regular exercise reduces functional loss associated with multiple sclerosis (MS). However, the impact of exercise on inflammatory mediators associated with disease activity remains relatively unexplored. The purpose of this study was to determine whether ambulatory MS subjects would respond similarly to aerobic cycle training compared with matched controls on circulating immune variables, interleukin (IL)-6, tumor necrosis factor (TNF)-α and interferon (IFN)-γ. Eleven MS and 11 non-MS control subjects (8 women and 3 men in both groups) matched in age, height, body mass, body fat, and peak O2 uptake completed the study. Subjects completed 30 min of cycle ergometry at 60% of peak O2 uptake, 3 day/wk for 8 wk. Plasma cytokine concentrations were determined before and after exercise at weeks 0, 4, and 8. MS and control subjects showed a similar cytokine responses to exercise. IL-6 at rest tended to decrease ( P = 0.08) with training in both groups. Resting plasma TNF-α tended to be higher in MS compared with controls throughout the study ( P = 0.08). MS subjects showed elevated resting TNF-α in MS at the end of the 8-wk program ( P = 0.04), whereas resting TNF-α remained unchanged in controls ( P > 0.05). Resting plasma IFN-γ at rest was elevated in MS subjects ( P = 0.008) and unchanged in controls at the end of the intervention ( P > 0.05). The response of plasma IL-6, TNF-α, and IFN-γ after a single bout of exercise was similar between MS and control subjects ( P > 0.05). Additional research to understand the impact of exercise on immune variables in MS is warranted.

Increased IL-10 mRNA and IL-23 mRNA expression in multiple sclerosis: interferon-beta treatment increases IL-10 mRNA expression while reducing IL-23 mRNA expression

BACKGROUND

Interferon (IFN)-beta therapy in multiple sclerosis (MS) has been suggested to promote a deviation from T lymphocyte production of pathogenic Th1 cytokines to less detrimental Th2 cytokines, but this is still controversial. We studied patterns of in vivo blood mononuclear cell (MNC) and whole blood cytokine and transcription factor mRNA expression before and during IFN-beta therapy in MS.

METHODS

Twenty patients with relapsing-remitting MS were sampled before and after 3 months of treatment with IFN-beta along with 15 healthy volunteers. An additional 39 patients and 50 healthy volunteers served to confirm initial findings. mRNA was analyzed by real-time reverse transcriptase polymerase chain reaction (PCR).

RESULTS

We found elevated expression of interleukin (IL)-23 and IL-10 in untreated MS patients. IFN-beta therapy increased IL-10 and decreased IL-23 expression independently of any Th1 or Th2 cytokines. The largest changes in cytokine mRNA levels occurred early (~9-12 h) after an IFN-beta injection.

CONCLUSION

We found no evidence of a Th1- or Th2-mRNA-promoting effect of IFN-beta therapy. The therapeutic effect of IFN-beta is more likely attributable to the induction of the regulatory cytokine IL-10. The elevated IL-23 mRNA levels in MS patients are noteworthy in view of the newly discovered IL-23-driven Th17 T-cell subset, which is crucial in animal models of MS. Since IFN-beta therapy resulted in decreased IL-23 mRNA levels, the Th17 axis could be another target of IFN-beta therapy.

Behavioral conditioning with interferon beta-1a in humans

Behavioral conditioning is one of the most impressive demonstrations of brain-immune system interaction. Numerous animal studies have demonstrated behavioral conditioned effects on immune functions, however, human studies are rare. We investigated whether it is possible to behaviorally condition the acute response to interferon (IFN)beta-1a. In a double-blind placebo-controlled study, 30 healthy subjects received a single injection of IFN(beta)-1a (6MIU of REBIF, Serono International) (unconditioned stimulus, UCS) together with a novel drink (conditioned stimulus, CS). Blood was drawn at baseline, 4, 8, and 24 h after drug administration. Within the first 8 h peripheral granulocytes significantly increased, while monocytes, lymphocytes, T-, B- and natural killer (NK) cell numbers were significantly reduced. In parallel, body temperature, heart rate, norepinephrine and interleukin (IL)-6 plasma levels were heightened within 8 h after injection. 8 days later, all previously IFN(beta)-treated subjects received a subcutaneous placebo (NaCl) injection, but only 15 subjects were re-exposed to the CS (experimental group), while a control group (N=15) drank water and an additional group of subjects (n=8) remained untreated (untreated group). Blood sampling was performed at baseline and at 4, 8, and 24 h. Re-exposition to the CS did not elicit conditioned responses in the experimental group. Moreover, no differences were observed between groups. These data provide negative findings regarding behavioral conditioning of cytokine effects in humans employing a one-trial learning paradigm.

In vitro modulation of the multiple sclerosis (MS)-associated retrovirus by cytokines: implications for MS pathogenesis

Multiple sclerosis (MS)-associated retrovirus (MSRV) is a component of the human endogenous retrovirus (HERV)-W family, with gliotoxic and superantigenic properties, related to MS clinical progression, and transactivated by viral agents. The authors studied MSRV modulation by cytokines involved in vivo in MS course, utilizing peripheral blood mononuclear cells from MSRV-positive and MRSV-negative individuals. Cultured cells from MSRV-negative subjects did not produce virus, whereas spontaneous MSRV release was detected in cultures from MSRV-positive donors; virus release was increased by interleukin (IL)-4 and IL-6 and, to a greater extent, by the detrimental cytokines interferon gamma and tumor necrosis factor (TNF)alpha. Interferon beta, used in MS therapy, inhibits MSRV release. A parallel between the effects of these cytokines on MSRV production in vitro and on MS disease in vivo is observed, which deserves further elucidations.

Acute interferon beta-1b administration alters hypothalamic-pituitary-adrenal axis activity, plasma cytokines and leukocyte distribution in healthy subjects

It has been suggested that the immune-endocrine communication plays an important role in development and progression of multiple sclerosis (MS). Interferon beta (IFN beta-1b) treatment is the therapy of choice in patients suffering from relapsing remitting or secondary chronic progressive multiple sclerosis. While typical adverse events of IFN beta-1b treatment such as flu-like symptoms or fatigue are well studied, little is known about the acute changes in the immune and neuroendocrine system. Therefore, we analyzed the short-term effects of IFN beta-1b on cortisol, epinephrine, norepinephrine, prolactin and growth hormone (GH) plasma levels before and 4, 8 and 24 h after IFN beta-1b administration in healthy subjects. Moreover, we determined heart rate, blood pressure, body temperature, leukocyte and lymphocyte subsets and plasma levels of interleukin (IL)-1 beta, IL-6, IL-10 and tumor necrosis factor (TNF)-alpha. IFN beta-1b led to an increase in body temperature and heart rate, and in parallel, elevated cortisol, prolactin and GH plasma levels at 4 and 8 h after IFN beta-1b injection. There were no significant alterations in blood pressure, norepinephrine or epinephrine plasma levels. Simultaneously, IFN beta-1b injection led to an immediate granulocytosis while concomitantly decreasing peripheral lymphocytes, especially natural killer (NK) cells. At the same time, IL-6, IL-10 and TNF-alpha plasma levels showed an overall increase. Overall, cytokine administration exerts strong stimulatory effects on the hypothalamic-pituitary-adrenal (HPA)-axis that may contribute to the side effects of IFN beta-1b therapy and affect the efficacy of IFN beta-1b treatment.

Innate immune responses in viral encephalitis

The innate immune system is multifaceted, comprised of preformed factors, cells, and many proteins and lipid mediators produced by those cells. In the CNS these are critical in initiation and amplification of the inflammatory response and in the subsequent elicitation of the specific T cell response to viral encephalitis. Cells that are resident in brain parenchyma and peripheral cells that are recruited both play key roles in the hosts's responses. Unlike the peripheral compartments, in the CNS, non-cytolytic means of eliminating viral infections have been critical, since, in contrast to columnar epithelial cells, neurons are non-renewing. When the innate immune responses are inefficient or absent in viral encephalitis, pathology is more likely. Much more work remains to elucidate all of the critical cells and their mediators, as well as to develop new therapies for infections of the CNS.

Multiple sclerosis: deficient in vitro responses of blood mononuclear cells to IFN-beta

IFN-beta may modify the clinical course of multiple sclerosis (MS) but is not curative, and there are also patients whose disease does not respond to IFN-beta as currently administered. Tests are warranted with a capacity to early discriminate responders from non-responders, thereby altering treatment option for the individual patient. In vitro effects of IFN-beta on expression of activation-associated cell surface markers and cytokine production need to be explored in this context. Here we report on the influence in vitro of IFN-beta on blood mononuclear cells (MNC) prepared from MS patients and healthy controls. MNC were subjected to short-term culture in the presence of IFN-beta at concentrations of 100 U/ml and 1000 U/ml. Expression of cell surface molecules CD40, CD69, CD80, CD86, CD95 and HLA-DR was measured by flow cytometry. IL-10 and IL-12 p40 production in culture supernatants was measured by ELISA. MNC exposed to IFN-beta in vitro enhanced expression of the co-stimulatory CD80, CD86, the early activation antigen CD69 and the cell death receptor CD95. Expression of CD40 and HLA-DR was not influenced. IFN-beta increased IL-10 but suppressed IL-12 p40 production. In vitro effects of IFN-beta on MNC were similar in MS patients and in healthy subjects, except that IFN-beta-induced augmentation of CD86 and CD69 expression was less pronounced in MS, in particular in untreated MS patients. Individual MS patients clearly responded differently to IFN-beta in vitro in comparison with the majority of patients in this cross-sectional study. In conclusion, anti-inflammatory effects of IFN-beta on blood MNC include augmentation of IL-10 production and suppression of IL-12 p40 production, which are accompanied by enhancement of CD69, CD80, CD86 and CD95 expression. The less pronounced IFN-beta-induced effects on CD86 and CD69 expression in MS vs controls might reflect a defect in immunoregulation in MS. Larger groups should be evaluated, and follow-up studies performed in MS patients before/during IFN-beta treatment in relation to clinical outcome measures to evaluate the usefulness of these markers for possible differentiation between responders and non-responders to IFN-beta treatment.

In vitro modulation of adhesion molecules, adhesion phenomena, and fluid phase endocytosis on human umbilical vein endothelial cells and brain-derived microvascular endothelium by IFN-beta 1a

Administration of interferon-beta (IFN-beta) in multiple sclerosis (MS) patients provides clinical benefits, although its mechanism(s) of action are not completely understood. We addressed the issue of whether concentrations of IFN-beta1a close to those reached in the serum of treated MS patients could modulate either adhesion molecules or adhesion of peripheral blood mononuclear cells (PBMC) as well as fluid phase endocytosis (FPE) in human umbilical vein endothelial cells (HUVEC) and in brain-derived microvascular endothelial cells (HBMEC). Adhesion was assessed by flow cytometry, and FPE was evaluated by peroxidase uptake. In our study, 200 U/ml IFN-beta1a induced a reduction in adhesion of PBMC to HUVEC. The information reported herein may contribute to further elucidating some of the mechanisms of action of IFN-beta on vascular endothelium.

Interferon beta1a treatment modulates TH1 expression in gammadelta + T cells from relapsing-remitting multiple sclerosis patients

A paradigm exists that multiple sclerosis is causally related to dysregulation of TH1 inflammatory cytokines and TH2 antiinflammatory cytokines. The cytokine source(s) that initiate the imbalances are unknown. In this study, gammadelta, CD4, and CD8 T cell receptor-positive (TCR+) cells were isolated from the blood of 26 definitive relapsing-remitting multiple sclerosis patients prior to interferon beta-1a (IFNbeta1a) therapy and following 8-10 weeks of this therapy. The bioactivities of interferon gamma (IFNgamma), interleukin 10 (IL10), and interleukin 12 (IL12) were determined. The concentrations of IFN-gamma, IL10, and IL12 from each cell type did not change significantly with IFNbeta1a treatment. The IL10 secreted by gammadelta TCR+ cells strongly correlated with the IL12 secreted by the same gammadelta TCR+ cells, supporting the paradigm. Furthermore, IFNbeta1a therapy decreased the gammadelta TCR+ cell secretion of TH1 cytokines after 8-10 weeks of therapy.

Serum and CSF levels of MCP-1 and IP-10 in multiple sclerosis patients with acute and stable disease and undergoing immunomodulatory therapies

The two chemokines, monocyte chemoattractant protein (MCP)-1 and gamma-interferon inducible protein (IP)-10, are thought to be involved in the pathogenesis of multiple sclerosis (MS). We measured MCP-1 and IP-10 levels in serum and CSF samples from 38 acute and 25 stable MS patients and from 40 controls. The latter consisted in patients with other inflammatory neurological diseases (OIND) or with non-inflammatory neurological diseases, and healthy controls. CSF MCP-1 levels exceeded those found in serum in all the patients studied as well as in healthy controls. CSF MCP-1 levels were significantly lower in acute MS [468+/-(S.E.M.) 18 pg/ml] than in stable MS (857+/-104 pg/ml). When detectable, serum and CSF IP-10 levels were significantly higher in acute MS (serum 331+/-66 pg/ml; CSF 118+/-16 pg/ml) than in stable MS (serum 69+/-7 pg/ml; CSF 25+/-2 pg/ml). Among OIND patients, those with HIV-1-associated dementia showed high serum and CSF levels of both MCP-1 and IP-10. Those with encephalitis showed high serum and CSF levels of IP-10 and CSF mononuclear pleiocytosis. We also evaluated the effects of 6-methylprednisolone or IFN-beta1a therapy on circulating MCP-1 and IP-10 levels. Neither MCP-1 nor IP-10 post-therapy levels varied significantly from baseline values. Our findings suggest that (a) MCP-1 could be constitutively produced within the brain; (b) MCP-1 and IP-10 CSF levels in acute MS vary significantly from those in stable MS, and these variations are inverse; and (c) current MS therapies do not modify circulating levels of MCP-1 and IP-10.

Interferon-beta1a administration results in a transient increase of serum amyloid A protein and C-reactive protein: comparison with other markers of inflammation

Putative markers of inflammation such as serum beta2-microglobulin and neopterin have been shown to be transiently upregulated following interferon-beta (IFN-beta) administration to multiple sclerosis (MS) patients. However, to date the role of the important inflammatory mediators serum amyloid A protein (SAA) and C-reactive protein (CRP) have not been described. Here we show that SAA but not CRP is elevated in relapsing-remitting MS patients compared to normal healthy individuals, and furthermore that both are transiently upregulated following intramuscular injection with IFN-beta1a (Avonex). This pattern of expression was found to parallel that of beta2-microglobulin and neopterin following injection and was mirrored by a selective activation of peripheral monocytes with respect to upregulation of receptors known to be involved in the inflammatory response (HLA-DR, CD16 and CD86). Injection of saline solution intramuscularly to six healthy control individuals did not produce a similar upregulation of any of the inflammatory markers investigated. Following IFN-beta1a injection, all inflammatory responses were attenuated at week 12 of therapy in comparison to those following the initial injection in a group of follow-up patients. In addition, IFN-beta1a injected on a weekly basis did not produce a sustained modulation of any of the markers investigated in patients treated for 32 weeks.

Multiple sclerosis: pro- and anti-inflammatory cytokines and metalloproteinases are affected differentially by treatment with IFN-beta

Interferon-beta (IFN-beta) has a beneficial influence on the course of multiple sclerosis (MS) and has become standard treatment of this disease, though its mechanisms of action are incompletely understood. This study examines the effect of IFN-beta treatment on the cytokines IL-6, TNF-alpha, IFN-gamma and IL-10; the metalloproteinases MMP-3, -7 and -9 and the tissue inhibitor of metalloproteinase-1 (TIMP-1). IFN-beta treatment resulted in decreased numbers of mononuclear cells (MNC) secreting IL-6 and TNF-alpha and expressing mRNA of MMP-3 and MMP-9 compared to pretreatment levels. On the contrary, numbers of IL-10 secreting MNC and TIMP-1 mRNA expressing were augmented during IFN-beta therapy. Whether the down-regulatory effects on pro-inflammatory and upregulatory effects on anti-inflammatory molecules are a direct result of IFN-beta on the immune system or secondary to clinical stabilization of MS pathology induced by IFN-beta remains to be evaluated.