Genetic variants in the tumor necrosis factor receptor II gene in patients with multiple sclerosis

Anti-TNF therapy for inflammatory bowel disease in patients with neurodegenerative Niemann-Pick disease Type C

Background:  Blockade of tumour necrosis factor (anti-TNF) is effective in patients with Crohn's Disease but has been associated with infection risk and neurological complications such as demyelination. Niemann-Pick disease Type C1 (NPC1) is a lysosomal storage disorder presenting in childhood with neurological deterioration, liver damage and respiratory infections. Some NPC1 patients develop severe Crohn's disease. Our objective was to investigate the safety and effectiveness of anti-TNF in NPC1 patients with Crohn's disease. Methods: Retrospective data on phenotype and therapy response were collected in 2019-2020 for the time period 2014 to 2020 from patients in the UK, France, Germany and Canada with genetically confirmed NPC1 defects and intestinal inflammation. We investigated TNF secretion in peripheral blood mononuclear cells treated with NPC1 inhibitor in response to bacterial stimuli . Results: NPC1 inhibitor treated peripheral blood mononuclear cells (PBMCs) show significantly increased TNF production after lipopolysaccharide or bacterial challenge providing a rationale for anti-TNF therapy. We identified 4 NPC1 patients with Crohn's disease (CD)-like intestinal inflammation treated using anti-TNF therapy (mean age of onset 8.1 years, mean treatment length 27.75 months, overall treatment period 9.25 patient years). Anti-TNF therapy was associated with reduced gastrointestinal symptoms with no apparent adverse neurological events. Therapy improved intestinal inflammation in 4 patients. Conclusions: Anti-TNF therapy appears safe in patients with NPC1 and is an effective treatment strategy for the management of intestinal inflammation in these patients.

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.

Cytokines and cytokine profiles in human autoimmune diseases and animal models of autoimmunity

The precise pathomechanisms of human autoimmune diseases are still poorly understood. However, a deepened understanding of these is urgently needed to improve disease prevention and early detection and guide more specific treatment approaches. In recent years, many new genes and signalling pathways involved in autoimmunity with often overlapping patterns between different disease entities have been detected. Major contributions were made by experiments using DNA microarray technology, which has been used for the analysis of gene expression patterns in chronic inflammatory and autoimmune diseases, among which were rheumatoid arthritis, systemic lupus erythematosus, psoriasis, systemic sclerosis, multiple sclerosis, and type-1 diabetes. In systemic lupus erythematosus, a so-called interferon signature has been identified. In psoriasis, researchers found a particular immune signalling cluster. Moreover the identification of a new subset of inflammatory T cells, so-called Th17 T cells, secreting interleukin (IL)-17 as one of their major cytokines and the identification of the IL-23/IL-17 axis of inflammation regulation, have significantly improved our understanding of autoimmune diseases. Since a plethora of new treatment approaches using antibodies or small molecule inhibitors specifically targeting cytokines, cellular receptors, or signalling mechanisms has emerged in recent years, more individualized treatment for affected patients may be within reach in the future.

An investigation of susceptibility loci in benign, aggressive and primary progressive multiple sclerosis in Northern Irish population

OBJECTIVE

To investigate the possibility that susceptibility loci in multiple sclerosis (MS) have a role in determining the disease outcome in Northern Ireland population.

BACKGROUND

The Genetic Analysis of Multiple Sclerosis in Europeans (GAMES) initiative and follow-up refined analysis identified 15 candidate susceptibility loci within the Northern Irish population for MS. We aimed to investigate the 12 most significant markers for their role in disease outcome.

METHODS

Cases with probable or definite MS (Poser criteria) were classified as benign onset (Kurtzke Expanded Disability Status Scale [EDSS]<or=3.0 at 10 years), aggressive (Kurtzke EDSS>or=6.0 by 10 years), or primary progressive MS. All cases were Caucasian of Northern Irish origin. DNA was extracted from venous blood, microsatellite markers were amplified using polymerase chain reaction and typed using fluorescent fragment analysis. Allele frequencies were compared statistically using a chi-squared test with allowance for multiple comparisons (critical P<0.0042); significant markers were further analyzed by CLUMP (critical P<0.0014).

RESULTS

Two microsatellite markers were significant: D3S1278 (Chr 3q13, P<0.001) and tumor necrosis factor (TNF)-alpha (Chr 6p21, P<0.001). A further three markers were significant in our preliminary analysis suggesting a trend toward impact on disease outcome; D4S432 (Chr 4p16, P=0.001), D2S347 (Chr 2q14, P=0.003), and D19S903 (Chr 19p13, P=0.003).

CONCLUSIONS

This is the first study to suggest a role for TNF-alpha in the disease outcome in MS. Larger replication studies need to be performed to assess the role of markers D4S432, D2S347, and D19S903.

Recent advances in genetic analysis of multiple sclerosis: genetic associations and therapeutic implications

Epidemiological studies have confirmed that genetic factors are a key component in the pathogenesis of multiple sclerosis (MS) and that those determining MS susceptibility have been extensively studied. Many papers have been published regarding the heritable differences useful in genetic studies; these include variations in DNA, such as single-nucleotide polymorphisms, microsatellites and insertion/deletion polymorphisms. However, to date, among other regions, HLA is the only region confirmed to possess genes that determine MS susceptibility. In this article, we review the progress during the last 5 years in the studies on the susceptibility genes and the pharmacogenetics of MS. Newer techniques and methods of analysis will hopefully result in better screening of individuals who are at highest risk and novel treatments.

Signatures of human regulatory T cells: an encounter with old friends and new players

BACKGROUND

Naturally occurring CD4+ CD25+ regulatory T cells (TReg) are involved in the control of autoimmune diseases, transplantation tolerance, and anti-tumor immunity. Thus far, genomic studies on TReg cells were restricted to murine systems, and requirements for their development, maintenance, and mode of action in humans are poorly defined.

RESULTS

To improve characterization of human TReg cells, we compiled a unique microarray consisting of 350 TReg cell associated genes (Human TReg Chip) based on whole genome transcription data from human and mouse TReg cells. TReg cell specific gene signatures were created from 11 individual healthy donors. Statistical analysis identified 62 genes differentially expressed in TReg cells, emphasizing some cross-species differences between mice and humans. Among them, several 'old friends' (including FOXP3, CTLA4, and CCR7) that are known to be involved in TReg cell function were recovered. Strikingly, the vast majority of genes identified had not previously been associated with human TReg cells (including LGALS3, TIAF1, and TRAF1). Most of these 'new players' however, have been described in the pathogenesis of autoimmunity. Real-time RT-PCR of selected genes validated our microarray results. Pathway analysis was applied to extract signaling modules underlying human TReg cell function.

CONCLUSION

The comprehensive set of genes reported here provides a defined starting point to unravel the unique characteristics of human TReg cells. The Human TReg Chip constructed and validated here is available to the scientific community and is a useful tool with which to study the molecular mechanisms that orchestrate TReg cells under physiologic and diseased conditions.

RON-regulated innate immunity is protective in an animal model of multiple sclerosis

The tyrosine kinase receptor RON and its ligand, macrophage stimulating protein (MSP), exert inhibitory effects on systemic innate immunity, but their CNS expression and impact on human neuroinflammatory diseases are unknown were RON and MSP present in human brain perivascular macrophages and microglia, but RON mRNA and protein abundance in the CNS were diminished in both MS patients and the MS animal model, experimental autoimmune encephalomyelitis (EAE). Treatment of differentiated human monocytoid cells with MSP resulted in significant reduction of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha and MMP-9 mRNA levels, whereas minimal effects were observed in human astrocytes. After induction of EAE, RON knockout and heterozygote animals exhibited significantly increased CNS proinflammatory gene (TNF-alpha, MMP-12) expression compared with wild-type littermate controls, although IL-4 levels were suppressed in both RON-deficient groups. Neurological disease in RON-deficient animals showed a more rapid onset with overall worsened severity, together with exacerbated demyelination, axonal injury, and neuroinflammation after EAE induction. The proto-oncogene, c-Cbl, which modulates ubiquitylation of RON, was increased in glia in both MS brains and EAE spinal cords. Thus, the MSP-RON pathway represents a novel regulatory mechanism within the CNS by which innate immunity and its pathogenic effects could be targeted for future therapeutic interventions.

A polymorphism in the 3' untranslated region of the gene for tumor necrosis factor receptor 2 modulates reporter gene expression

The gene encoding the human TNF alpha receptor (TNFR) 2 contains polymorphisms in the 3' untranslated region (UTR). Previous studies have shown that some variant alleles in this region are associated with obesity and insulin resistance. However, the effect of these polymorphisms on the expression of TNFR2 has not been studied to date. To examine the role played by different haplotypes in the control of TNFR2 expression (haplotypes A1-A5, referring to nucleotides 1663 G/A, 1668 T/G, and 1690 T/C), we introduced these sequences into the 3'-UTR of a heterologous reporter gene and expressed the corresponding constructs in a human T-cell line. We demonstrate that a 485-nt fragment of the TNFR2 3'-UTR that contains a U-rich region decreases reporter expression and that haplotypes A1-A4 exert a stronger effect than A5. Furthermore, time-course assays of mRNA stability using actinomycin D revealed that haplotypes A1-A4 destabilize the mRNA. The proximal TNFR2 3'-UTR, independently of haplotype differences, responded to T-cell activation by increasing mRNA decay. Electromobility shift analysis demonstrated that protein(s) found in T-cell extracts bind to the 485-nt fragment. We suggest that an increased rate of TNFR2 mRNA decay protects cells from unrestrained TNF alpha effects and that this protection is weakened in A5 subjects. These findings may explain the association of this haplotype with obesity and increased leptin levels.