Reduced Expression of PD-1 in Circulating CD4+ and CD8+ Tregs Is an Early Feature of RRMS

Expression of STAT- and T-cell-related genes in women with first-line treatment of relapsing-remitting multiple sclerosis

Relapsing-remitting multiple sclerosis is associated with changes in Jak/STAT pathways in immune cells, but the influence of disease-modifying drugs on these pathways is poorly understood. The aim of this study was to evaluate the impact of first-line disease-modifying drugs used in treatment of RRMS on expression of the STAT pathway and T-cell-related genes in the blood and on serum concentrations of sgp130 and TGF-β1 in women, as well as on the level of phosphorylated STAT3 and STAT5 proteins in T cells of untreated patients and heathy controls. Expression of STAT1, STAT3, STAT5A, STAT5B, SOCS1, SOCS3, FOXP3, IKZF2, RORC and ICOS genes in the blood of untreated RRMS patients, in the blood of patients treated with interferon-β, glatiramer acetate, dimethyl fumarate or teriflunomide and in the blood of healthy controls was evaluated using droplet digital PCR. Serum concentrations of sgp130 and TGF-β1 were evaluated by ELISA. Phosphorylated STAT3 and STAT5 protein levels in T cells were evaluated by flow cytometry. STAT3 gene expression was significantly higher in untreated patients than in healthy control, but the level of phosphorylated STAT3 in T cells was significantly lower. Patients treated with interferon-β or dimethyl fumarate had significantly lower STAT3 gene expression. Patients treated with teriflunomide had higher STAT1 gene expression, than untreated patients. Patients treated with dimethyl fumarate also had significantly lower RORC gene expression than untreated patients. The study shows the impact of drugs used in first-line treatment of relapsing-remitting multiple sclerosis on expression of STAT and T-cell-related genes.

Melatonin synergistically potentiates the effect of methylprednisolone on reducing neuroinflammation in the experimental autoimmune encephalomyelitis mouse model of multiple sclerosis

Multiple sclerosis (MS) is an autoimmune neurodegenerative disease of unknown etiology characterized by infiltration of encephalitogenic cells in the central nervous system (CNS) resulting in the presence of multifocal areas of demyelination leading to neurodegeneration. The infiltrated immune cells population is composed mainly of effector CD4+ and CD8+ T lymphocytes, B cells, macrophages, and dendritic cells that secrete pro-inflammatory factors that eventually damage myelin leading to axonal damage. The most common clinical form of MS is relapsing-remitting (RR), characterized by neuroinflammatory episodes followed by partial or total recovery of neurological deficits. The first-line treatment for RRMS relapses is a high dose of glucocorticoids, especially methylprednisolone, for three to five consecutive days. Several studies have reported the beneficial effects of melatonin in the context of neuroinflammation associated with MS or experimental autoimmune encephalomyelitis (EAE), the preclinical model for MS. Therefore, the objective of this study was to evaluate the effect of the combined treatment of melatonin and methylprednisolone on the neuroinflammatory response associated with the EAE development. This study shows for the first time the protective synergistic effect of co-treatment with melatonin and methylprednisolone on reducing the severity of EAE by decreasing CD4 lymphocytes, B cells, macrophages and dendritic cells in the CNS, as well as modulating the population of infiltrated T and B cells toward regulatory phenotypes to the detriment of pro-inflammatory effector functions. In addition to the potentiation of the protective role of methylprednisolone, treatment with melatonin from the clinical onset of EAE improves the natural course of the EAE and the response to a subsequent treatment with methylprednisolone in a later relapse of the disease, pointing melatonin as potential therapeutic tool in combination with methylprednisolone for the treatment of relapses in MS.

Effects of High Efficacy Multiple Sclerosis Disease Modifying Drugs on the Immune Synapse: A Systematic Review

BACKGROUND

Co-signaling and adhesion molecules are important elements for creating immune synapses between T lymphocytes and antigen-presenting cells; they positively or negatively regulate the interaction between a T cell receptor with its cognate antigen, presented by the major histocompatibility complex.

OBJECTIVES

We conducted a systematic review on the effects of High Efficacy Disease Modifying Drugs (HEDMDs) for Multiple Sclerosis (MS) on the co-signaling and adhesion molecules that form the immune synapse.

METHODS

We searched EMBASE, MEDLINE, and other sources to identify clinical or preclinical reports on the effects of HEDMDs on co-signaling and adhesion molecules that participate in the formation of immune synapses in patients with MS or other autoimmune disorders. We included reports on cladribine tablets, anti- CD20 monoclonal antibodies, S1P modulators, inhibitors of Bruton's Tyrosine Kinase, and natalizumab.

RESULTS

In 56 eligible reports among 7340 total publications, limited relevant evidence was uncovered. Not all co-signaling and adhesion molecules have been studied in relation to every HEDMD, with more data being available on the anti-CD20 monoclonal antibodies (that affect CD80, CD86, GITR and TIGIT), cladribine tablets (affecting CD28, CD40, ICAM-1, LFA-1) and the S1P modulators (affecting CD86, ICAM-1 and LFA-1) and less on Natalizumab (affecting CD80, CD86, CD40, LFA-1, VLA-4) and Alemtuzumab (affecting GITR and CTLA-4).

CONCLUSION

The puzzle of HEDMD effects on the immune synapse is far from complete. The available evidence suggests that distinguishing differences exist between drugs and are worth pursuing further.

Long non-coding RNAs BACE1-AS and BC200 in multiple sclerosis and their relation to cognitive function: A gene expression analysis

Cognitive impairment is a common and debilitating feature of multiple sclerosis (MS), and the dysregulation of synaptic plasticity is one of its direct causes. Long non-coding RNAs (lncRNAs) have been shown to play a role in synaptic plasticity, but their role in cognitive impairment in MS has not been fully explored. In this study, using quantitative real-time PCR, we examined the relative expression of two specific lncRNAs, BACE1-AS and BC200, in the serum of two cohorts of MS patients with and without cognitive impairment. Both lncRNAs were overexpressed in both cognitively impaired and non-cognitively impaired MS patients, with consistently higher levels in the cohort with cognitive impairment. We also found a strong positive correlation between the expression levels of these two lncRNAs. Notably, BACE1-AS was consistently higher in the remitting cases of both relapsing-remitting MS (RRMS) and secondary progressive MS (SPMS) groups than in the respective relapse cases of the same subtype, with the SPMS-Remitting group of cognitively impaired MS patients showing the highest expression of BACE1-AS among all MS groups. Additionally, we observed that the primary progressive MS (PPMS) group had the highest expression of BC200 in both cohorts of MS. Furthermore, we developed a model called Neuro_Lnc-2, which showed better diagnostic performance than either BACE1-AS or BC200 alone in predicting MS. Our findings suggest that these two lncRNAs may have a significant impact on the pathogenesis of the progressive types of MS and on the cognitive function of the patients. Future research is required to confirm these findings.

The Immune Response to Nematode Infection

Nematode infection is a major threat to the health of humans, domestic animals and wildlife. Nematodes vary in their effect on the host and in the mechanisms underlying immunity but the general features are becoming clear. There is considerable variation among individuals in resistance to infection and much of this variation is due to genetic variation in the immune response. The major histocompatibility complex has a strong influence on resistance to infection but other genes are collectively more important. Resistant individuals produce more IgA, eosinophils, IgE and mast cells than susceptible individuals and this is a consequence of stronger type 2 (Th2) immune responses. A variety of factors promote Th2 responses including genetic background, diet, molecules produced by the parasite and the location of the infection. A variety of cells and molecules including proteins, glycolipids and RNA act in concert to promote responses and to regulate the response. Nematodes themselves also modulate the host response and over 20 parasite-derived immunomodulatory molecules have been identified. Different species of nematodes modulate the immune response in different ways and probably use multiple molecules. The reasons for this are unclear and the interactions among immunomodulators have still to be investigated.

Autoreactive lymphocytes in multiple sclerosis: Pathogenesis and treatment target

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by destruction of the myelin sheath structure. The loss of myelin leads to damage of a neuron’s axon and cell body, which is identified as brain lesions on magnetic resonance image (MRI). The pathogenesis of MS remains largely unknown. However, immune mechanisms, especially those linked to the aberrant lymphocyte activity, are mainly responsible for neuronal damage. Th1 and Th17 populations of lymphocytes were primarily associated with MS pathogenesis. These lymphocytes are essential for differentiation of encephalitogenic CD8⁺ T cell and Th17 lymphocyte crossing the blood brain barrier and targeting myelin sheath in the CNS. B-lymphocytes could also contribute to MS pathogenesis by producing anti-myelin basic protein antibodies. In later studies, aberrant function of Treg and Th9 cells was identified as contributing to MS. This review summarizes the aberrant function and count of lymphocyte, and the contributions of these cell to the mechanisms of MS. Additionally, we have outlined the novel MS therapeutics aimed to amend the aberrant function or counts of these lymphocytes.

Crosstalk between dendritic cells and regulatory T cells: Protective effect and therapeutic potential in multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system related to autoimmunity and is characterized by demyelination, neuroinflammation, and neurodegeneration. Cell therapies mediated by dendritic cells (DCs) and regulatory T cells (Tregs) have gradually become accumulating focusing in MS, and the protective crosstalk mechanisms between DCs and Tregs provide the basis for the efficacy of treatment regimens. In MS and its animal model experimental autoimmune encephalomyelitis, DCs communicate with Tregs to form immune synapses and complete a variety of complex interactions to counteract the unbalanced immune tolerance. Through different co-stimulatory/inhibitory molecules, cytokines, and metabolic enzymes, DCs regulate the proliferation, differentiation and function of Tregs. On the other hand, Tregs inhibit the mature state and antigen presentation ability of DCs, ultimately improving immune tolerance. In this review, we summarized the pivotal immune targets in the interaction between DCs and Tregs, and elucidated the protective mechanisms of DC-Treg cell crosstalk in MS, finally interpreted the complex cell interplay in the manner of inhibitory feedback loops to explore novel therapeutic directions for MS.