Neuroprotection by upregulation of the major histocompatibility complex class I (MHC I) in SOD1G93A mice

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that progressively affects motoneurons, causing muscle atrophy and evolving to death. Astrocytes inhibit the expression of MHC-I by neurons, contributing to a degenerative outcome. The present study verified the influence of interferon β (IFN β) treatment, a proinflammatory cytokine that upregulates MHC-I expression, in SOD1G93A transgenic mice. For that, 17 days old presymptomatic female mice were subjected to subcutaneous application of IFN β (250, 1,000, and 10,000 IU) every other day for 20 days. Rotarod motor test, clinical score, and body weight assessment were conducted every third day throughout the treatment period. No significant intergroup variations were observed in such parameters during the pre-symptomatic phase. All mice were then euthanized, and the spinal cords collected for comparative analysis of motoneuron survival, reactive gliosis, synapse coverage, microglia morphology classification, cytokine analysis by flow cytometry, and RT-qPCR quantification of gene transcripts. Additionally, mice underwent Rotarod motor assessment, weight monitoring, and neurological scoring. The results show that IFN β treatment led to an increase in the expression of MHC-I, which, even at the lowest dose (250 IU), resulted in a significant increase in neuronal survival in the ALS presymptomatic period which lasted until the onset of the disease. The treatment also influenced synaptic preservation by decreasing excitatory inputs and upregulating the expression of AMPA receptors by astrocytes. Microglial reactivity quantified by the integrated density of pixels did not decrease with treatment but showed a less activated morphology, coupled with polarization to an M1 profile. Disease progression upregulated gene transcripts for pro- and anti-inflammatory cytokines, and IFN β treatment significantly decreased mRNA expression for IL4. Overall, the present results demonstrate that a low dosage of IFN β shows therapeutic potential by increasing MHC-I expression, resulting in neuroprotection and immunomodulation.

Elispot assay detection of cytokine secretion in multiple sclerosis patients treated with interferon-b1a or glatiramer acetate compared with untreated patients

The mechanisms behind the beneficial effects of interferon-b1a (IFN-b1a) and glatiramer acetate (GA) in the treatment of multiple sclerosis (MS) are still uncertain. A ltered cytokine patterns have been suggested including inhibition of proinflammatory cytokines like interferon-g (IFN-g) and enhancement of anti-inflammato ry cytokines such as interleukin-4 (IL-4). Twenty-nine patients with MS (10 untreated, nine treated with IFN-b1a and 10 with GA) were investigated with elispot of peripheral blood mononuclear cells. Spontaneous and myelin induced (myelin basic protein (MBP), myelin oligodendro cyte glycoprotein (MO G)-14-39 and MO G 63-87) IFN-g, IL-4, IL-5 and IL-10 secretion was studied. We found a significant reduction of spontaneous IFN-g, 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-g 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 MO G 14-39 induced IL-4 secretion in the IFN-b1a treated group. Thus, immunological effects of IFN-b1a and G A were similar showing that disease promoting Th1 (IFN-g) cells were reduced while the potentially beneficial Th2 response (IL-4) was maintained.

Longitudinal interferon-β effects in multiple sclerosis: differential regulation of IL-10 and IL-17A, while no sustained effects on IFN-γ, IL-4 or IL-13

BACKGROUND

Recent studies in experimental models and in vitro indicate lowering of IL-17/Th17 as an important mechanism of interferon-beta (IFN-β) treatment in multiple sclerosis (MS).

MATERIAL AND METHODS

In this longitudinal study of MS patients (n=25), spontaneous and myelin antigen-induced secretion of IL-4, IFN-γ and IL-10 (ELISPOT), mitogen stimulated secretion of IL-13 and IL-17A (ELISA) and circulating cytokine levels (Luminex) were recorded at inclusion and after 1.5, 3, 6 and 12months of IFN-β treatment.

RESULTS

Early changes were noted for IL-4, while after one year of treatment the only recorded significant effects were a decrease in secreted IL-17A levels and an increase in IL-10 secreting cells. While IL-17A levels tended to be higher in non-responders (n=8), the decrease in IL-17A levels seemed to be more pronounced in responders (n=17) showing significantly lower IL-17A levels after one year as compared with non-responders.

CONCLUSION

IFN-β treatment seems to mainly affect IL-17/IL-10-associated pathways rather than the IFN-γ/IL-4 axis.

Lymphocyte Subpopulations, Oxidative Burst and Apoptosis in Peripheral Blood Cells of Patients with Multiple Sclerosis–Effect of Interferon-β

At present, the most efficient therapeutical treatment of multiple sclerosis (MS) is achieved by IFN-beta. However, its in vivo effects remain incompletely understood. If applied parenterally, the hydrophobic IFN-beta acts primarily on blood cells with probable selectivity for functionally different lymphocyte subpopulations, monocytes and granulocytes. We have investigated the expression of the activation marker interleukin-2 receptor-alpha (CD25) on CD3+ T cells, CD19+ B cells, foetal-type gamma(delta)+CD3+ T cells and foetal-type CD5+CD19+ B cells of the peripheral blood. In addition, the oxidative burst activity and apoptosis have been determined in mononuclear and polymorphonuclear blood cells, respectively. The study accompanied a phase III trial with IFN-beta1b (BETAFERON, Schering). Two groups of MS patients with relapsing-remitting course of the disease have been investigated at 8 time points (days 0, 5, 15, 31, 60, 90, 180 and 270 after starting therapy): (1) verum group (n = 8) with application of 8 Mill. units IFN-beta1 b every other day, and (2) placebo group (n = 4) with application of placebo for 3 months and therapy as in (1) from day 90 onward. The main results were: (1) Activated T cells decreased until day 180 in the verum group and return thereafter to pre-treatment values, whereas in the placebo group the values remained relatively stable over the whole observation period. (2) Activated B cells increased between days 90 and 270 in both groups, i.e. after verum application in both groups. (3) Foetal-type B cells were more activated than total B and T cells with increase over time in both groups. (4) Foetal-type T cells exerted relatively stable intra-individual levels with generally low CD25 expression, but punctual CD25 peaks in both groups. (5) The spontaneous oxidative burst was higher in lymphocytes, more variable in monocytes and faster increasing in granulocytes in the verum group than in the placebo group. (6) Apoptosis of mononuclear cells and granulocytes showed similar variations in the verum and placebo groups with the exception of a selective increase over time of the proportion of granulocytes undergoing induced apoptosis in the verum group. It is concluded that IFN-beta has the following main effects on the immune system of MS patients: (1) the T cell immunity is systemically and reversibly suppressed, (2) the foetal-type lymphocytes, which are responsible for the first line of defence of infections, are stimulated in the long range, (3) the oxidative burst activity is increased in lymphocytes and granulocytes and instable in monocytes, and (4) the inducibility of apoptosis in granulocytes is increased. Re-examination of the altered blood cell parameters after long-term IFN-beta therapy is warranted.

Prior poliomyelitis-evidence of cytokine production in the central nervous system

In order to study the role of a possible inflammatory reaction in the post-polio syndrome (PPS) four key cytokines were determined by means of mRNA expression in mononuclear cells from cerebrospinal fluid (CSF) and peripheral blood of 13 patients. Data were compared with those of samples from eight non-inflammatory control persons. The PPS-patients displayed increased numbers of CSF cells expressing mRNA for TNF-alpha (p<0.02), IFN-gamma (p<0.02), IL-4 (p<0.001) and IL-10 (p<0.05), in comparison to the non-inflammatory controls. As positive controls, samples from patients with Multiple Sclerosis (MS) were examined. We conclude that there is a chronic intra CNS expression of inflammatory cytokines in PPS, in the range of that in MS, a well known neuroinflammatory disease. However, the pathogenic significance of this is unclear.

Depletion of Vbeta5.2/5.3 T cells with a humanized antibody in patients with multiple sclerosis

A potentially pathogenic expansion of T cells expressing T cell receptor (TCR) Vbeta5.2/5.3 has been demonstrated in patients with multiple sclerosis (MS). A humanized antibody (ATM-027) directed against these T cells has been developed to further investigate the role of this subpopulation of T cells in MS. The pharmacokinetics/dynamics and safety of ATM-027 (0.3-300 mg intravenously over 30 min) were investigated in 14 patients with MS. The effect of treatment on cytokine expression and autoreactivity to peptides of myelin basic protein (MBP) was also studied. ATM-027 was well tolerated and raised no safety concerns. Clearance of the antibody was low and elimination half-life was approximately 3 weeks. The majority of the target Vbeta5.2/5.3 expressing T cells were depleted for at least 18 months. The small remaining fraction of target cells showed a marked decrease in their TCR expression, which was recovered within 8 months. The numbers of peripheral blood mononuclear cells (PBMCs) with spontaneous expression of IFN-gamma was decreased at 72 h and 8 weeks after treatment, whilst no clear effects on TNF-alpha, IL-4, IL-10, TGF-beta expression were observed. There was also a significant decrease in the number of PBMCs producing IFN-gamma in response to MBP peptide 80-102. We conclude that long-term depletion of T cells expressing defined Vbeta subgroups in MS patients is feasible using selective immunotherapy. The selective depletion of Vbeta5.2/5.3 expressing T cells in this study resulted in a decrease in potentially disease promoting anti-MBP reactivity and pro-inflammatory cytokine production.

Reduction of both pro- and anti-inflammatory cytokines after 6 months of interferon beta-1a treatment of multiple sclerosis

Treatment of multiple sclerosis (MS) with interferon beta (IFNbeta) reduces relapse rate, magnetic resonance imaging (MRI) activity and progression of disability. It has been suggested that this beneficial effect is paralleled by an inhibition of proinflammatory cytokines such as interferon gamma (IFNgamma) and tumor necrosis factor alpha (TNFalpha) and an induction of anti-inflammatory cytokines such as interleukin-4 (IL-4) and interleukin-10 (IL-10). In this study, we record a reduced number of spontaneously IFNgamma mRNA-expressing cerebrospinal fluid mononuclear cells (CSF-MC) and IFNgamma, TNFalpha and IL-10 mRNA-expressing peripheral blood mononuclear cells (PBMC) after 6 months of IFNbeta-1a treatment, paralleled by a decreased purified protein derivate (PPD)-stimulated and unstimulated IFNgamma secretion by PBMC. These effects were not apparent after 2 weeks of treatment, and IFNbeta-1a induced IFNgamma production by naive PBMC in vitro. We did not record increased numbers of IL-4 mRNA-expressing CSF-MC or PBMC, increased plasma IL-10 levels, increased numbers of IgG, A or M secreting plasma cells or in vitro induction of IL-10 production by IFNbeta-1a. We conclude that long-term cytokine modulation by IFNbeta-1a differs from acute effects and that downregulation of both pro- and anti-inflammatory cytokines, rather than a shift in the cytokine profile, is apparent after 6 months of IFNbeta-1a treatment of MS patients.

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

It has been postulated that the efficacy of interferon-beta1a in multiple sclerosis may be due to the induction of type 2 cytokines. In this report we demonstrate that after 3 months of therapy, there is no sustained alteration in the plasma levels of type 1 (IL-12, IL-1beta and TNF-alpha) or type 2 (IL-6, IL-10) cytokines, but rather repeated induction of both with each injection. Little alteration is seen in the profile of cytokines induced with time, despite a decline in side effects. This suggests that IFN-beta1a causes repeated transient modulation of cytokine expression, but no sustained deviation in the type 1/type 2 balance.

IFN-beta suppresses experimental autoimmune neuritis in Lewis rats by inhibiting the migration of inflammatory cells into peripheral nervous tissue

The putative prophylactic and therapeutic effect of interferon-beta (IFN-beta) on autoimmune inflammation of the peripheral nervous system was evaluated in experimental autoimmune neuritis (EAN), a well-known animal model of the human Guillain-Barré syndrome (GBS). We report that treatment of rats with 300,000 U of recombinant rat IFN-beta (rrIFN-beta) given every other day starting at the day of immunization prevented clinical signs of EAN. When treatment was started at the onset of disease development, the cytokine clearly ameliorated EAN. Both B- and T-cell responses towards peripheral myelin were suppressed by the IFN-beta, and immunohistochemical analyses revealed a strong decrease in the numbers of infiltrating CD4(+) T cells, macrophages, and other inflammatory cells as well as a significant reduction in MHC class II antigen expression and monocyte chemotactic protein-1 (MCP-1) production, which induces chemotaxis and chemokinesis of leukocytes from blood. It is concluded that the observed suppression of EAN by rrIFN-beta is associated with a decrease in the migration of inflammatory cells into peripheral nervous tissue.