Klarissa Hanja Stürner

Antigen-Specific Tolerance by Autologous Myelin Peptide–Coupled Cells: A Phase 1 Trial in Multiple Sclerosis

Antigen-coupled cells result in antigen-specific tolerization for treatment of multiple sclerosis. Multiple Sclerosis Therapy Attached at the Hip In multiple sclerosis (MS), a patient’s own immune cells are thought to attack antigens in the brain and spinal cord. One approach to prevent this attack is through tolerization: harnessing one way the body itself attempts to prevent autoimmunity. Ideally, this would happen in an antigen-specific way so that autoimmunity is blocked, while the protective functions of the immune system remain intact. There has been considerable success inducing antigen-specific tolerance in mouse models of MS by chemically coupling the antigen of choice to carrier cells. Now, Lutterotti et al. take this approach into human patients. The authors coupled peripheral blood mononuclear cells from MS patients with seven different myelin peptides thought to be potentially antigenic in MS. Patients who had T cell responses restricted to at least one of the peptides tested were selected. Indeed, patients who received the highest doses of antigen-coupled cells demonstrated decreases in antigen-specific T cell responses after therapy. Although the patient numbers are small in this first-in-human study, the safety, feasibility, and early results suggest that this approach may provide a promising avenue for future trials. Multiple sclerosis (MS) is a devastating inflammatory disease of the brain and spinal cord that is thought to result from an autoimmune attack directed against antigens in the central nervous system. The aim of this first-in-man trial was to assess the feasibility, safety, and tolerability of a tolerization regimen in MS patients that uses a single infusion of autologous peripheral blood mononuclear cells chemically coupled with seven myelin peptides (MOG1–20, MOG35–55, MBP13–32, MBP83–99, MBP111–129, MBP146–170, and PLP139–154). An open-label, single-center, dose-escalation study was performed in seven relapsing-remitting and two secondary progressive MS patients who were off-treatment for standard therapies. All patients had to show T cell reactivity against at least one of the myelin peptides used in the trial. Neurological, magnetic resonance imaging, laboratory, and immunological examinations were performed to assess the safety, tolerability, and in vivo mechanisms of action of this regimen. Administration of antigen-coupled cells was feasible, had a favorable safety profile, and was well tolerated in MS patients. Patients receiving the higher doses (>1 × 109) of peptide-coupled cells had a decrease in antigen-specific T cell responses after peptide-coupled cell therapy. In summary, this first-in-man clinical trial of autologous peptide-coupled cells in MS patients establishes the feasibility and indicates good tolerability and safety of this therapeutic approach.

Novel treatment of ovarian cancer cell lines with Imatinib mesylate combined with Paclitaxel and Carboplatin leads to receptor-mediated antiproliferative effects.

PurposeImatinib is a small molecule inhibiting the tyrosine kinases bcr-abl, c-kit, PDGFR-α and PDGFR-β. Investigations were performed to screen ovarian cancer cell lines and tumor samples for target receptor expression. Effects of Imatinib on cell proliferation and apoptosis induction were measured with and without additional cytotoxic agents.MethodsExpression patterns of abl, c-kit, PDGFR-α and PDGFR-β (Imatinib targets) were studied in 5 cell lines and 111 tissue arrays by PCR and immunohistochemistry. Proliferation assays were performed with single agent Imatinib or combined with Paclitaxel and Carboplatin. Apoptosis was measured by DNA fragmentation.ResultsAll cell lines expressed abl and PDGFR-β. C-kit was only expressed in 2/5 cell lines and PDGFR-α in 4/5. Imatinib reduced cell growth and lead to pro-apoptotic changes. Combination of Carboplatin, Paclitaxel and Imatinib showed synergistic activity.ConclusionsOur results suggest that Imatinib may be useful for the specific treatment of ovarian cancer as an add-on to conventional chemotherapy.

Novel multiple sclerosis susceptibility loci implicated in epigenetic regulation.

Genome-wide study in Germans identifies four novel multiple sclerosis risk genes and confirms already known gene loci. We conducted a genome-wide association study (GWAS) on multiple sclerosis (MS) susceptibility in German cohorts with 4888 cases and 10,395 controls. In addition to associations within the major histocompatibility complex (MHC) region, 15 non-MHC loci reached genome-wide significance. Four of these loci are novel MS susceptibility loci. They map to the genes L3MBTL3, MAZ, ERG, and SHMT1. The lead variant at SHMT1 was replicated in an independent Sardinian cohort. Products of the genes L3MBTL3, MAZ, and ERG play important roles in immune cell regulation. SHMT1 encodes a serine hydroxymethyltransferase catalyzing the transfer of a carbon unit to the folate cycle. This reaction is required for regulation of methylation homeostasis, which is important for establishment and maintenance of epigenetic signatures. Our GWAS approach in a defined population with limited genetic substructure detected associations not found in larger, more heterogeneous cohorts, thus providing new clues regarding MS pathogenesis.

Switch to Efavirenz in a Protease Inhibitor-Containing Regimen

Abstract Purpose: This report evaluated the efficacy and safety of switching from a protease inhibitor (PI)-containing HIV treatment regimen to an efavirenz (EFV)-containing regimen. Method: We retrospectively analyzed data from 64 patients, with a plasma viral load (VL) less than 50 copies/mL and CD4+ counts >200 cells/mL at baseline, who had been taking a regimen consisting of a PI and two nucleoside reverse transcriptase inhibitors (NRTIs; d4T/3TC [n = 45]; AZT/3TC [n = 19]) for a median of 27.5 months (range, 6-41 months) and who chose to substitute EFV for the PIs in the regimens. Statistical analyses were performed by Wilcoxon test. Fat atrophy was evaluated by physician’s assessment and patients’ subjective self-estimation with the criteria of well being and body state. Results: 57 patients completed 36 weeks on the EFV regimen; 4 patients changed therapy but continued EFV, 2 moved to another area, and 1 discontinued EFV. During the first weeks of therapy, 56.3% of patients suffered from moderate nervous system symptoms. The plasma VL of 63 patients remained at <50 copies/mL at final analysis. Compared with time of switching to EFV, analysis at 36 weeks showed no statistically significant change from 626±283 to 643±296 cells/mL in mean absolute CD4+ cells and a statistically significant increase from 26.8±9.6% to 28.0±9.1% in relative CD4+ cells. There was a statistically significant reduction in relative CD8+CD38+ from 62.2±16.3% at time of switching to EFV to 55.1±15.0% at week 36. At baseline, 27 patients suffered from lipodystrophy, including fat atrophy and fat accumulation. After 36 weeks, nine patients showed intensified fat atrophy. In contrast, five patients improved their state concerning fat redistribution and 13 patients showed no alterations. Conclusion: The switch to a non-PI-containing regimen with EFV offers a good drug alternative for patients with suppressed viral load, problems of adherence, and/or adverse events due to PIs but not for patients suffering from lipoatrophy caused by nucleoside reverse transcriptase inhibitors. The intention of such a switch aims at the avoidance of fatal mutations in HIV.

A Multiple Sclerosis–Associated Variant of CBLB Links Genetic Risk with Type I IFN Function

Multiple sclerosis (MS) is an autoimmune disease of the CNS, and autoreactive CD4+ T cells are considered important for its pathogenesis. The etiology of MS involves a complex genetic trait and environmental triggers that include viral infections, particularly the EBV. Among the risk alleles that have repeatedly been identified by genome-wide association studies, three are located near the Casitas B-lineage lymphoma proto-oncogene b gene (CBLB). The CBLB protein (CBL-B) is a key regulator of peripheral immune tolerance by limiting T cell activation and expansion and hence T cell–mediated autoimmunity through its ubiquitin E3-ligase activity. In this study, we show that CBL-B expression is reduced in CD4+ T cells from relapsing-remitting MS (RR-MS) patients during relapse. The MS risk-related single nucleotide polymorphism of CBLB rs12487066 is associated with diminished CBL-B expression levels and alters the effects of type I IFNs on human CD4+ T cell proliferation. Mechanistically, the CBLB rs12487066 risk allele mediates increased binding of the transcription factor C/EBPβ and reduced CBL-B expression in human CD4+ T cells. Our data suggest a role of the CBLB rs12487066 variant in the interactions of a genetic risk factor and IFN function during viral infections in MS.

Distinct functionality of neutrophils in multiple sclerosis and neuromyelitis optica

Background: In contrast to multiple sclerosis (MS), lesions in neuromyelitis optica (NMO) frequently contain neutrophils. However, the phenotypic profile of neutrophils in these two distinct pathologies remains unknown. Objective: Our aim is to better understand the potential contribution of neutrophils to NMO and MS pathology. Methods: We performed the first functional analysis of blood neutrophils in NMO and MS, including evaluation of neutrophil immune response (fMLP receptor, TLR2), chemotaxis and migration (CXCR1, CD62L, CD43), regulation of complement (CD46, CD55, CD59), respiratory burst, phagocytosis and degranulation. Results: Compared with healthy controls (HC), neutrophils in NMO and MS show an activated phenotype characterized by an increased surface expression of TLR2 and fMLP receptor. However, contrary to MS neutrophils, NMO neutrophils show reduced adhesion and migratory capacity as well as decreased reduced production of reactive oxygen species (respiratory burst) and degranulation. Conclusion: Although NMO and MS neutrophils display an activated phenotype in comparison with HC, NMO neutrophils show a compromised functionality when compared with MS patients. These results suggest a distinct functional profile of neutrophils in MS and NMO.

Regression to the Mean and Predictors of MRI Disease Activity in RRMS Placebo Cohorts - Is There a Place for Baseline-to-Treatment Studies in MS?

Background Gadolinium-enhancing (GD+) lesions and T2 lesions are MRI outcomes for phase-2 treatment trials in relapsing-remitting Multiple Sclerosis (RRMS). Little is known about predictors of lesion development and regression-to-the-mean, which is an important aspect in early baseline-to-treatment trials. Objectives To quantify regression-to-the-mean and identify predictors of MRI lesion development in placebo cohorts. Methods 21 Phase-2 and Phase-3 trials were identified by a systematic literature research. Random-effects meta-analyses were performed to estimate development of T2 and GD+ after 6 months (phase-2) or 2 years (phase-3). Predictors of lesion development were evaluated with mixed-effect meta-regression. Results The mean number of GD+-lesions per scan was similar after 6 months (1.19, 95%CI: 0.87-1.51) and 2 years (1.19, 95%CI: 1.00-1.39). 39% of the patients were without new T2-lesion after 6 month and 19% after 2 years (95%CI: 12-25%). Mean number of baseline GD+-lesions was the best predictor for new lesions after 6 months. Conclusion Baseline GD-enhancing lesions predict evolution of Gd- and T2 lesions after 6 months and might be used to control for regression to the mean effects. Overall, proof-of-concept studies with a baseline to treatment design have to face a regression to 1.2 GD+lesions per scan within 6 months.

Boswellic acids reduce Th17 differentiation via blockade of IL-1β-mediated IRAK1 signaling.

Interferon‐gamma producing CD4+ T (Th1) cells and IL‐17‐producing CD4+ T (Th17) cells are involved in the pathogenesis of several autoimmune diseases including multiple sclerosis. Therefore, the development of treatment strategies controlling the generation and expansion of these effector cells is of high interest. Frankincense, the resin from trees of the genus Boswellia, and particularly its prominent bioactive compound acetyl‐11‐keto‐β‐boswellic acid (AKBA), have potent anti‐inflammatory properties. Here, we demonstrate that AKBA is able to reduce the differentiation of human CD4+ T cells to Th17 cells, while slightly increasing Th2‐ and Treg‐cell differentiation. Furthermore, AKBA reduces the IL‐1β‐triggered IL‐17A release of memory Th17 cells. AKBA may affect IL‐1β signaling by preventing IL‐1 receptor‐associated kinase 1 phosphorylation and subsequently decreasing STAT3 phosphorylation at Ser727, which is required for Th17‐cell differentiation. The effects of AKBA on Th17 differentiation and IL‐17A release make the compound a good candidate for potential treatment of Th17‐driven diseases.

Successful Replication of GWAS Hits for Multiple Sclerosis in 10,000 Germans Using the Exome Array.

Genome‐wide association studies (GWAS) successfully identified various chromosomal regions to be associated with multiple sclerosis (MS). The primary aim of this study was to replicate reported associations from GWAS using an exome array in a large German study. German MS cases (n = 4,476) and German controls (n = 5,714) were genotyped using the Illumina HumanExome v1‐Chip. Genotype calling was performed with the Illumina Genome StudioTM Genotyping Module, followed by zCall. Single‐nucleotide polymorphisms (SNPs) in seven regions outside the human leukocyte antigen (HLA) region showed genome‐wide significant associations with MS (P values < 5 × 10−8). These associations have been reported previously. In addition, SNPs in three previously reported regions outside the HLA region yielded P values < 10−5. The effect of nine SNPs in the HLA region remained (P < 10−5) after adjustment for other significant SNPs in the HLA region. All of these findings have been reported before or are driven by known risk loci. In summary, findings from previous GWAS for MS could be successfully replicated. We conclude that the regions identified in previous GWAS are also associated in the German population. This reassures the need for detailed investigations of the functional mechanisms underlying the replicated associations.

A standardised frankincense extract reduces disease activity in relapsing-remitting multiple sclerosis (the SABA phase IIa trial)

Objective To investigate whether oral administration of a standardised frankincense extract (SFE) is safe and reduces disease activity in patients with relapsing-remitting multiple sclerosis (RRMS). Methods We performed an investigator-initiated, bicentric phase IIa, open-label, baseline-to-treatment pilot study with an oral SFE in patients with RRMS (NCT01450124). After a 4-month baseline observation phase, patients were treated for 8 months with an option to extend treatment for up to 36 months. The primary outcome measures were the number and volume of contrast-enhancing lesions (CEL) measured in MRI during the 4-month treatment period compared with the 4-month baseline period. Eighty patients were screened at two centres, 38 patients were included in the trial, 28 completed the 8-month treatment period and 18 of these participated in the extension period. Results The SFE significantly reduced the median number of monthly CELs from 1.00 (IQR 0.75–3.38) to 0.50 (IQR 0.00–1.13; difference −0.625, 95% CI −1.25 to −0.50; P<0.0001) at months 5–8. We observed significantly less brain atrophy as assessed by parenchymal brain volume change (P=0.0081). Adverse events were generally mild (57.7%) or moderate (38.6%) and comprised mainly gastrointestinal symptoms and minor infections. Mechanistic studies showed a significant increase in regulatory CD4+ T cell markers and a significant decrease in interleukin-17A-producing CD8+ T cells indicating a distinct mechanism of action of the study drug. Interpretation The oral SFE was safe, tolerated well and exhibited beneficial effects on RRMS disease activity warranting further investigation in a controlled phase IIb or III trial. Clinical trial registration NCT01450124; Results.