Early identification of interferon-beta responders by ex vivo testing in patients with multiple sclerosis.

Interferon-beta (IFN-beta) is an effective treatment for a subgroup of patients with multiple sclerosis (MS). The mechanism of action as well as the pathophysiological basis of responsiveness to IFN-beta is not well understood. To improve treatment considerations in MS patients predictive markers for response to IFN-beta therapy at early timepoints are needed. Here we correlated changes in serum cytokine levels (IL-13, IL-10, IL-5, IL-4, IFN-gamma) with the clinical response to IFN-beta treatment. Serum cytokine levels of 77 untreated and 43 IFN-beta treated relapsing-remitting MS patients (RRMS) were measured by ELISA, including longitudinal measurements in 17 patients. We found a significant upregulation of IL-10 and IL-5 serum cytokine levels during IFN-beta therapy. However, clinical response was only associated with IL-10 serum levels (p=0.038; positive predictive value 0.95, negative predictive value 0.43) but not with IL-5. The predictive power was increased by a combined testing of IL-10 with expression of co-signaling molecules on monocytes, that were previously shown to change during IFN-beta therapy. In a subgroup of 17 patients testing of 4 markers had a positive and negative predictive value of 1.0 for at least 2 of these markers being positive in treatment responders. The results suggest that serum IL-10 is useful to predict treatment response to IFN-beta particularly in combination with a panel of other IFN-beta dependent parameters.

Effects of interferon-beta on co-signaling molecules: upregulation of CD40, CD86 and PD-L2 on monocytes in relation to clinical response to interferon-beta treatment in patients with multiple sclerosis.

Interferon-beta (IFN-beta) reduces disease activity in a subgroup of patients with relapsing remitting multiple sclerosis (MS). The mechanism of action as well as the pathophysiological basis of responsiveness to IFN-beta is not well understood. Since T-cell activation plays an important part in the pathophysiology of MS, we here investigated the effect of IFN-beta on the expression of co-signaling pathways (CD28-CD80/CD86, CD154-CD40, ICOS-ICOSL, PD-1-PD-L1/2) in MS patients and correlated the results with the clinical response to IFN-beta in individual patients. Expression of co-signaling molecules was measured by flow cytometry in vitro on peripheral blood mononuclear cells after incubation with IFN-beta, and in vivo in whole blood samples of 32 untreated and 24 IFN-beta treated MS patients, including 13 patients longitudinal. IFN-beta treatment induced upregulation of CD40, CD80, CD86, PD-L1 and PD-L2 on monocytes as well as PD-L1 on CD4+-T-cells in vitro and in vivo. IFN-beta treated MS patients were grouped into responders and non-responders on the basis of Kurtzkés EDSS (expanded disability status scale) progression and relapse rate. Upregulation of CD40, CD86 and PD-L2 on monocytes was associated with treatment response to IFN-beta (P < 0.001, P = 0.028 and P = 0.028, respectively). Our results show that IFN-beta upregulates co-stimulatory as well as co-inhibitory molecules in vitro and in vivo implicating that modulation of the balance between positive and negative co-stimulatory signals might be an important part of the mechanism of action of IFN-beta in MS. Upregulation of the expression of CD40, CD86 and PD-L2 may be useful as a predictive marker for clinical response to IFN-beta treatment at early timepoints during IFN-beta therapy.

Spontaneous intracranial hypotension: correlation of imaging findings with clinical features.

BACKGROUND: Spontaneous intracranial hypotension (SIH) is increasingly recognized as a clinically variable and likely underdiagnosed syndrome caused by non-traumatic CSF leaks. The aim of this study was to correlate the findings of imaging studies - magnetic resonance imaging (MRI), radionuclide cisternography - with clinical features and CSF pressure in SIH in order to improve the diagnostic yield and management in patients with SIH. METHODS: Clinical case study of 10 consecutive cases of SIH, MRI, radio-isotope cisternography. RESULTS: 5 out of 10 patients had unusual clinical symptoms of SIH(2 subdural haematomas, 1 gait ataxia, 1 tinnitus, 1 haemodialysis-associated headache). In 7 patients pachymeningeal gadolinium enhancement was detected in MRI accompanied by a reduced CSF opening pressure. In contrast, the 3 patients with normal MRI also had a normal CSF pressure. Radio-isotope cisternography was abnormal in all patients tested. There was no correlation between the severity of clinical symptoms and MRI or radionuclide cisternography findings. CONCLUSIONS: The spectrum of clinical symptoms and imaging findings in SIH is highly variable. There- fore the diagnosis of SIH is often delayed. Radio-isotope cisternography is an important additional diagnostic method to detect CSF leaks or pathological kinetics of radio-isotope movement particularly in cases with normal MRI findings.

Interferon-beta increases the stimulatory capacity of monocyte-derived dendritic cells to induce IL-13, IL-5 and IL-10 in autologous T-cells.

Dendritic cells (DCs) are key regulators of immune responses and have been associated with autoimmunity in animal models and human disease. The effects of interferon beta (IFN-beta), an immunomodulatory cytokine used in multiple sclerosis (MS) therapy, on DCs are not well understood. Monocyte-derived DCs at different stages of maturation were stimulated with IFN-beta and DC-phenotype and stimulatory function were measured. IFN-beta inhibited the development of DCs at early stages but enhanced DC maturation. Moreover, IFN-beta enhanced the capacity of DCs to stimulate autologous T-cells to secrete IL-13, IL-10 and IL-5. Thus, IFN-beta has both immunostimulatory and immunosuppressive effects on DCs depending on the stage of maturation.