Regulation of IL-10 and IL-17 mediated experimental autoimmune encephalomyelitis by S-nitrosoglutathione

Therapeutic potential of targeting IL-17 and its receptor signaling in neuroinflammation

T helper 17 cells are thought to significantly contribute to the neuroinflammation process during neurogenerative diseases via their signature cytokine, interleukin (IL)-17. Recently, an emerging key role of IL-17 and its receptors has been documented in inflammatory and autoimmune diseases. The clinical studies conducted on patients with neurodegenerative disease have also shown an increase in IL-17 levels in serum as well as cerebrospinal fluid samples. Therapeutic targeting of either IL-17 receptors or direct IL-17 neutralizing antibodies has shown a promising preclinical and clinical proof of concept for treating chronic autoimmune neurodegenerative diseases such as multiple sclerosis. Thus, IL-17 and its receptors have a central role in regulation of neuroinflammation and can be considered as one of the major therapeutic targets in chronic neuroinflammatory diseases.

The Role of CD4+ T Cells in the Immunotherapy of Brain Disease by Secreting Different Cytokines

Upon different stimulation, naïve CD4⁺ T cells differentiate into various subsets of T helper (Th) cells, including Th1, Th2, Th17, and Tregs. They play both protective and pathogenic roles in the central nervous system (CNS) by secreting different cytokines. Failure of the homeostasis of the subgroups in the CNS can result in different brain diseases. Recently, immunotherapy has drawn more and more attention in the therapy of various brain diseases. Here, we describe the role of different CD4⁺ T cell subsets and their secreted cytokines in various brain diseases, as well as the ways in which by affecting CD4⁺ T cells in therapy of the CNS diseases. Understanding the role of CD4⁺ T cells and their secreted cytokines in the immunotherapy of brain disease will provide new targets and therapeutics for the treatment of brain disease. The role of CD4 + T cell subtypes in different diseases and their associated regulatory genes, proteins, and enzymes. CD4 + T cell subtypes play both protective (green) and pathogenic (red) roles in different brain diseases. The immune regulatory effects of CD4 + T cells and their subtypes are promoted or inhibited by different genes, proteins, and enzymes.

Endothelial nitric oxide synthase-engineered mesenchymal stromal cells induce anti-inflammation in experimental immune models

BACKGROUND AIMS

Mesenchymal stromal cells (MSCs) remain an area of interest in the field of regenerative medicine. Although there is clear evidence of safety, a lack of substantial efficacy has led to many MSC-based clinical trials to stall in phase 1. Therefore, potentiating MSCs with biologically relevant messenger RNA (mRNA) transcripts presents a relatively safe and efficient way to increase functionality.

METHODS

In this study, human bone marrow-derived MSCs were transfected with endothelial nitric oxide synthase (eNOS) mRNA and evaluated for transfection efficiency and immunosuppressive ability. To assess MSC-eNOS functionality, T-cell proliferation assays and mouse models of experimental autoimmune encephalomyelitis and graft-versus-host disease were used.

RESULTS

The authors found that MSC-eNOS retained MSC characteristics and exhibited significantly enhanced immunosuppressive effects compared with naive MSCs in both in vitro and in vivo models.

CONCLUSIONS

It is feasible to pursue eNOS mRNA transfection to potentiate the immunomodulatory capacity of MSCs for clinical applications in the future.

Vascular and immunopathological role of Asymmetric Dimethylarginine (ADMA) in Experimental Autoimmune Encephalomyelitis

Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide synthase (NOS) inhibitor/uncoupler inducing vascular pathology. Vascular pathology is an important factor for the development and progression of CNS pathology of MS, yet the role of ADMA in MS remains elusive. Patients with multiple sclerosis (MS) are reported to have elevated blood levels of ADMA, and mice with experimental autoimmune encephalomyelitis (EAE, an animal model of MS) generated by auto-immunization of myelin oligodendrocyte glycoprotein (MOG) and blood-brain barrier (BBB) disruption by pertussis toxin also had increased blood ADMA levels in parallel with induction of clinical disease. To explore the role of ADMA in EAE pathogenesis, EAE mice were treated with a daily dose of ADMA. It is of special interest that ADMA treatment enhanced the BBB disruption in EAE mice and exacerbated the clinical and CNS disease of EAE. ADMA treatment also induced the BBB disruption and EAE disease in MOG-immunized mice even without pertussis toxin treatment, suggesting the role of ADMA in BBB dysfunction in EAE. T-cell polarization studies also documented that ADMA treatment promotes T_H 1- and T_H 17-mediated immune responses but without affecting Treg-mediated immune response in EAE mice as well as in in vitro T-cell culture. Taken together, these data, for the first time, document the vascular and immunopathogenic roles of ADMA in EAE, thus pointing to the potential of ADMA-mediated mechanism as a new target of potential therapy for MS.

Regulation of B cell functions by S-nitrosoglutathione in the EAE model

B cells play both protective and pathogenic roles in T cell-mediated autoimmune diseases by releasing regulatory vs. pathogenic cytokines. B cell-depleting therapy has been attempted in various autoimmune diseases but its efficacy varies and can even worsen symptoms due to depletion of B cells releasing regulatory cytokines along with B cells releasing pathogenic cytokines. Here, we report that S-nitrosoglutathione (GSNO) and GSNO-reductase (GSNOR) inhibitor N6022 drive upregulation of regulatory cytokine (IL-10) and downregulation of pathogenic effector cytokine (IL-6) in B cells and protected against the neuroinflammatory disease of experimental autoimmune encephalomyelitis (EAE). In human and mouse B cells, the GSNO/N6022-mediated regulation of IL-10 vs. IL-6 was not limited to regulatory B cells but also to a broad range of B cell subsets and antibody-secreting cells. Adoptive transfer of B cells from N6022 treated EAE mice or EAE mice deficient in the GSNOR gene also regulated T cell balance (Treg > Th17) and reduced clinical disease in the recipient EAE mice. The data presented here provide evidence of the role of GSNO in shifting B cell immune balance (IL-10 > IL-6) and the preclinical relevance of N6022, a first-in-class drug targeting GSNOR with proven human safety, as therapeutics for autoimmune disorders including multiple sclerosis.

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GSNO and GSNOR inhibitor (N6022) upregulates IL-10 and downregulates IL-6 in B cells.

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GSNO/N6022-mediated cytokine regulation occurs in a broad range of B cell subsets.

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GSNO/N6022 treatment ameliorates autoimmune disease of EAE.

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B cell transfer from N6022-treated or GSNOR null EAE mice to EAE mice shifts T cell balance (Treg > Th17) and alleviates EAE.

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The data provide the first insight into the therapeutic potential of GSNO/N6022 targeting B cells in multiple sclerosis.

Hypoxia-inducible factor-1 drives divergent immunomodulatory functions in the pathogenesis of autoimmune diseases

Hypoxia-inducible factor-1 (HIF-1) is a heterodimeric (HIF-1α/ HIF-1β) transcription factor in which the oxygen-sensitive HIF-1α subunit regulates gene transcription to mediate adaptive tissue responses to hypoxia. HIF-1 is a key mediator in both regulatory and pathogenic immune responses, because ongoing inflammation in localized tissues causes increased oxygen consumption and consequent hypoxia within the inflammatory lesions. In autoimmune diseases, HIF-1 plays complex and divergent roles within localized inflammatory lesions by orchestrating a critical immune interplay sponsoring the pathogenesis of the disease. In this review, we have summarized the role of HIF-1 in lymphoid and myeloid immunomodulation in autoimmune diseases. HIF-1 drives inflammation by controlling the Th17/T_reg /Tr1 balance through the tipping of the differentiation of CD4⁺ T cells in favour of pro-inflammatory Th17 cells while suppressing the development of anti-inflammatory T_reg /Tr1 cells. On the other hand, HIF-1 plays a protective role by facilitating the expression of anti-inflammatory cytokine IL-10 in and expansion of CD1d^hi CD5⁺ B cells, known as regulatory B cells or B10 cells. Apart from lymphoid cells, HIF-1 also controls the activation of macrophages, neutrophils and dendritic cells, thus eventually further influences the activation and development of effector/regulatory T cells by facilitating the creation of a pro/anti-inflammatory microenvironment within the autoinflammatory lesions. Based on the critical immunomodulatory roles that HIF-1 plays, this master transcription factor seems to be a potent druggable target for the treatment of autoimmune diseases.

Deep learning of the role of interleukin IL-17 and its action in promoting cancer

In breast cancer patients, metastasis remains a major cause of death. The metastasis formation process is given by an interaction between the cancer cells and the microenvironment that surrounds them. In this article, we develop a mathematical model that analyzes the role of interleukin IL-17 and its action in promoting cancer and in facilitating tissue metastasis in breast cancer, using a dynamic analysis based on a stochastic process that accounts for the local and global action of this molecule. The model uses the Ornstein–Uhlembeck and Markov process in continuous time. It focuses on the oncological expansion and the interaction between the interleukin IL-17 and cell populations This analysis tends to clarify the processes underlying the metastasis expansion mechanism both for a better understanding of the pathological event and for a possible better control of therapeutic strategies.

IL-17 is a proinflammatory interleukin that acts when there is tissue damage or when there is a pathological situation caused by an external pathogen or by a pathological condition such as cancer.

This research is focused on the role of interleukin IL-17 which, especially in the case of breast cancer, turns out to be a dominant “communication pin” since it interconnects with the activity of different cell populations affected by the oncological phenomenon. Stochastic modeling strategies, specially the Ornstein-Uhlenbeck process, with the aid of numerical algorithms are elaborated in this review.

The role of IL-17 is discussed in this manuscript at all the stages of cancer. It is discussed that IL-17 also acts as “metastasis promoter” as a result of its proinflammatory nature. The stochastic nature of IL-17 is discussed based on the evidence provided by recent literature.

The resulting dynamical analysis can help to select the most appropriate therapeutic strategy.

Cancer cells, in the case of breast cancer, have high level of IL-17 receptors (IL-17R); therefore the interleukin itself has direct effects on these cells. Immunotherapy research, focused on this cytokine and interlinked with the stochastic modeling, seems to be a promising avenue.

Nitroglycerin ameliorates liver injury and regulates adaptive immunity in mice

This study aimed to assess the protective effect of nitroglycerin, a commonly used drug in cardiovascular diseases, on mice with acute liver injury induced by carbon tetrachloride (CCl₄ ). The mice were randomly divided into three groups: control, CCl₄ , and CCl₄  + nitroglycerin. They were killed at 0, 6, 12, 24, and 48 h after treatment. Blood and liver tissue samples were collected for analysis. Analysis of the amounts of serum alanine aminotransferase (ALT)/aspartate aminotransferase (AST), hepatic glutathione (GSH), and malondialdehyde (MDA) showed that nitroglycerin protected against CCl₄ -induced acute liver injury. Liver histological analysis provided further evidence of the protective effect of nitroglycerin. Furthermore, we found that nitroglycerin suppressed the increase of T helper 17 (Th17) cells in CCl₄ -induced acute liver injury mice. The results indicate that nitroglycerin is a potential candidate for hepatic disease.

NLRP3 gain-of-function in CD4+ T lymphocytes ameliorates experimental autoimmune encephalomyelitis

NLRP3 inflammasome [NLR (nucleotide-binding domain, leucine-rich repeat containing protein) Pyrin-domain-containing 3 ] functions as an innate sensor of several PAMPs and DAMPs (pathogen- and damage-associated molecular patterns). It has been also reported as a transcription factor related to Th2 pattern, although its role in the adaptive immunity has been controversial, mainly because the studies were performed using gene deletion approaches. In the present study, we have investigated the NLRP3 gain-of-function in the context of encephalomyelitis autoimmune disease (EAE), considered to be a Th1- and Th17-mediated disease. We took advantage of an animal model with NLRP3 gain-of-function exclusively to T CD4⁺ lymphocytes (CD4CreNLRP3fl/fl). These mice presented reduced clinical score, accompanied by less infiltrating T CD4⁺ cells expressing both IFN-γ and IL-17 at the central nervous system (CNS) during the peak of the disease. However, besides NLRP3 gain-of-function in lymphocytes, these mice lack NLRP3 expression in non-T CD4⁺ cells. Therefore, in order to circumvent this deficiency, we transferred naive CD4⁺ T cells from WT, NLRP3-/- or CD4CreNLRP3fl/fl into Rag-1-/- mice and immunized them with MOG_35-55 Likewise, the animals repopulated with CD4CreNLRP3fl/fl T CD4⁺ cells presented reduced clinical score and decreased IFN-γ production at the peak of the disease. Additionally, primary effector CD4⁺ T cells derived from these mice presented reduced glycolytic profile, a metabolic profile compatible with Th2 cells. Finally, naive CD4⁺ T cells from CD4CreNLRP3fl/fl mice under a Th2-related cytokine milieu cocktail exhibited in vitro an increased IL-4 and IL-13 production. Conversely, naive CD4⁺ T cells from CD4CreNLRP3fl/fl mice under Th1 differentiation produced less IFN-γ and T-bet. Altogether, our data evidence that the NLRP3 gain-of-function promotes a Th2-related response, a pathway that could be better explored in the treatment of multiple sclerosis.