IL-17+ CD8+ T cell suppression by dimethyl fumarate associates with clinical response in multiple sclerosis

Immunosuppressive role of benzo[a]pyrene exposure in prostate cancer progression

Epidemiological studies indicate that prostate cancer (PCa) is the second prevalent malignant tumor affecting men globally. Environmental pollution such as cigarette smoke is one of the important risk factors for the development of prostate cancer. However, as one of the main carcinogens in cigarette smoke, the role of benzo[a]pyrene (BaP) in prostate cancer is still unclear. The current study aimed to investgate the impacts of BaP exposure on the progression of PCa toward malignancy and the regulation of the immune microenvironment. We verified that BaP exposure can promote the proliferation, migration, and apoptosis of prostate cancer cells through in vitro experiments. We constructed a subcutaneous xenograft tumor model of BaP exposure mouse and found that can promote the proliferation of tumors in vivo. Organoids-driven by PCa patients showed higher growth rate under BaP exposure. Flow cytometric analysis demonstrated a remarkable decrease in CD4+ T and CD8+ T cell infiltration levels. Moreover, we identified four genes (Mdm2, Ar, Foxo1, Crebbp) were strongly associated with BaP exposure by combining mouse tumor RNA-seq and CTD database. Additionally, a nomogram integrating clinicopathological features was constructed to assess the prognosis of prostate cancer patients under BaP exposure. This study systematically proved that BaP exposure promotes malignant progression of PCa and suppresses the immune microenvironment, in which Mdm2, Ar, Foxo1, Crebbp may play a crucial role in inhibiting apoptosis. These findings offer novel insights into the mechanisms via which BaP exposure contributes to PCa development.

Varicella-Zoster virus associated vasculopathy in a young male multiple sclerosis patient, treated with dimethyl fumarate

With the increasing use of disease modifying therapies as treatment for multiple sclerosis, knowledge of the rare but possibly severe adverse events becomes increasingly important. We present a case of Varicella-Zoster virus associated vasculopathy in a young male multiple sclerosis patient, treated with dimethyl fumarate. We aim to address this rare but potentially deadly complication of varicella-Zoster virus infection and spread awareness about the increased risk in this patient population.

Targeting PD-1 and CD85j can restore intratumoral CD4+ GzmB+ T-cell functions to combat MHC-II-expressing tumors

BACKGROUND

A subset of CD4+ T cells with cytotoxic activity has been identified, and these cells exert their effects by expressing perforin and granzymes. Despite the progress made in characterizing cytotoxic CD4+ T cells in various diseases, the status of cytotoxic CD4+ T cells in non-small cell lung cancer (NSCLC) and the underlying mechanisms involved in promoting intratumoral cytotoxic CD4+ T-cell activation remain unclear.

METHODS

We used flow cytometry to examine the phenotypic and functional properties of CD4+GzmB+ T cells in the peripheral blood and tumor tissues of patients with NSCLC. Loss-of-function analyses and RNA sequencing were used to identify the underlying mechanisms involved in the effects of interleukin (IL)-15 on the restoration of CD4+GzmB+ T-cell function in vitro. A patient-derived lung cancer explant model and an animal model were used to verify the effects of immune checkpoint inhibitors on CD4+GzmB+ T-cell activation.

RESULTS

In patients with NSCLC, impaired cytolytic function of tumor-infiltrated granzyme B (GzmB)-expressing CD4+ T cells was restored by IL-15 through activation of the AKT-FOXO1-T-bet axis. Moreover, IL-15 stimulation increased solute carrier family 7 member 5 (SLC7A5) expression in CD4+GzmB+ T cells in an Protein Kinase B (AKT)-dependent manner, and inhibition of SLC7A5 abrogated the effect of IL-15 on CD4+GzmB+ T cells. Additionally, we showed that the immune checkpoint molecules programmed cell death-1 (PD-1) and CD85j were mutually exclusively expressed in CD4+GzmB+ T cells and that dual targeting of PD-1 and CD85j enhanced the effector function of CD4+GzmB+ T cells by activating the AKT pathway. Notably, tumor cells expressing major histocompatibility complex (MHC)-II and IL-15 determine the effectiveness of CD4+GzmB+ T-cell-mediated antitumor immunity in response to immunotherapy.

CONCLUSIONS

Our study demonstrated that tumor-infiltrating CD4+GzmB+ T cells fail to eliminate tumors. Dual blockade of PD-1 and CD85j alongside IL-15 restores the effector function of CD4+GzmB+ T cells and drives CD4+GzmB+ T-cell transformation in the tumor microenvironment to combat MHC-II-expressing tumors.

Reduced monocytic IL10 expression in PD1 inhibitor-treated patients is a harbinger of severe immune-related adverse events

BACKGROUND

Despite remarkable clinical efficacy, little is known about the system-wide immunological alterations provoked by PD1 blockade. Dynamics of quantitative immune composition and functional repertoire during PD1 blockade could delineate cohort-specific patterns of treatment response and therapy-induced toxicity.

METHODS

We longitudinally assessed therapy-induced effects on the immune system in fresh whole blood using flow cytometry-based cell quantifications, accompanied by analyses of effector properties of all major immune populations upon cell-type specific stimulations. 43 cancer patients undergoing PD1 blockade were recruited with assessments performed pre-treatment and before cycles 2/4/6, which resulted in the collection of more than 30,000 cytometric data values.

RESULTS

We observed no intrinsic immune pattern correlating with clinical outcome before PD1 blockade initiation, but cohort-specific immune alterations emerged during therapy. The most striking evolving changes in therapy responders were an increase in activated T and NK cell subsets, which showed high IFNγ and TNFα expression upon ex vivo stimulation. Patients affected by severe immune-related adverse events (s-irAE) presented with an analogously increased number of activated CD4 + and CD8 + T cells compared to patients with no/mild irAE, but lacked the functional divergences observed between responders versus non-responders. Instead, their monocytes showed discriminatory functional deficits with less IL10 production upon stimulation, which led to an abrogated inhibition of T cell proliferation in vitro and thus may account for the observed T cell expansion in patients with s-irAE.

CONCLUSION

Our holistic explorative approach allowed the delineation of clinically relevant cohorts by treatment-triggered immune changes, potentially enabling better patient stratification and further revealed new mechanistic insights into the pathogenesis of s-irAE.

Sportizumab - Multimodal progressive exercise over 10 weeks decreases Th17 frequency and CD49d expression on CD8+ T cells in relapsing-remitting multiple sclerosis: A randomized controlled trial

BACKGROUND

Multiple Sclerosis (MS) represents a neuroinflammatory autoimmune disease characterized by the predominance of circulating T cell subsets with proinflammatory characteristics and increased central nervous system (CNS)-homing potential. Substantial evidence confirms various beneficial effects of chronic exercise interventions in MS, but it is unknown how long-term multi-modal intense exercise affects MS-associated lymphocytes that are commonly targeted by medication in persons with relapsing remitting MS (pwRRMS).

METHODS

A total of 45 participants with defined RRMS were randomized to either the exercise (n = 22) or passive waitlist-control group (n = 23). A 10-week intervention consisting of progressive resistance and strength-endurance exercises was applied (3x/week à 60 min). Blood was drawn before (T1) and after (T2) the intervention period. Flow cytometry was used for phenotyping lymphocyte subsets.

RESULTS

Relative protein expression of CD49d within CD8+ T cells, quantified via mean fluorescence intensity (MFI), is significantly associated with the Expanded Disability Status Scale (p = 0.007, r = 0.440), decreased in the exercise group (p = 0.001) only, and was significantly lower in the exercise compared to the control group at T2 (p < 0.001). T helper (Th) 17 cell frequency decreased only in the exercise group (p < 0.001). CD8+CD20+ T cell frequency was significantly lower in the exercise compared to the control group at T2 (p = 0.003), without showing significant time effects.

CONCLUSION

The 10-week multimodal exercise intervention mainly affected circulating T cells harboring a pathophysiological phenotype in MS. The findings of a decreased frequency of pathogenic Th17 cells and the reduced CNS-homing potential of CD8+ T cells, indicated by reduced CD49d MFI, substantiate the positive effects of exercise on cellular biomarkers involved in disease activity and progression in MS. To confirm exercise-mediated beneficial effects on both disease domains, clinical endpoints (i.e., relapse rate, lesion formation, EDSS score) should be assessed together with these cellular and molecular markers in studies with a larger sample size and a duration of six to twelve months or longer.

Double negative T cells promote surgery-induced neuroinflammation, microglial engulfment and cognitive dysfunction via the IL-17/CEBPβ/C3 pathway in adult mice

CD3(+) CD4(-) CD8(-) double negative T cells (DNTs) manifest themselves in autoimmune diseases and associated inflammation. In the central nervous system, the increased presence of DNTs is associated with the progression of neurological conditions and brain injury. Active DNTs that produce IL-17 have been regarded as a pro-inflammatory phenotype. The IL-17 signaling pathway mediates neuroinflammatory responses by inducing glial activation and producing inflammatory factors. Neuroinflammation is considered integral to the pathogenesis of perioperative neurocognitive disorders (PNDs), commonly developed after surgery in susceptible patients. We and others have demonstrated a significant role for complement C3 in surgery-induced neuroinflammation and cognitive impairment but the regulatory mechanisms for this remain unexplored. We hypothesized that surgery induces DNT infiltration into the CNS that in turn upregulates complement C3 expression and this causes changes that contribute to cognitive impairment. Using an adult murine abdominal surgery model, we investigated perioperative changes in cognitive performance, quantifying the presence of T cell subsets and phenotype, IL-17 signaling pathway activation, glial cell activation and C3 expression in the brain. Postoperative IL-17 specific inhibitor GSK2981278 administration or preoperatively conditional CEBPβ knock-down by AAV9 viral vector were then applied to evaluate the effect of inhibiting IL-17 signaling pathway on postoperative C3 expression and cognitive performance. The results showed an increased hippocampus infiltration of DNTs with augmented IL-17 production, along with C3 upregulation and cognitive impairment. Both inhibition of IL-17 or knock-down of CEBPβ significantly suppressed C3 expression, synaptic engulfment by microglia and attenuated cognitive impairment. These findings indicate that DNTs promote postoperative neuroinflammation and cognitive impairment via the IL-17/CEBPβ/C3 pathway and targeting this IL-17 axis could be a potential therapeutic strategy to ameliorate postoperative neuroinflammation and cognitive impairment.

Acetyl 11-Keto Beta-Boswellic Acid Improves Neurological Functions in a Mouse Model of Multiple Sclerosis

Acetyl-11-keto-β-boswellic acid is one of the main active components of Boswellia sp. resin with the most potent anti-inflammatory activity. In recent years, herbal therapy has received considerable attention for the treatments of inflammatory and demyelinating diseases such as Multiple sclerosis (MS). Studies have shown that herbal compounds could enhance myelin repair and suppress inflammation. This study was designed to investigate the therapeutic effects of intraperitoneal administration of AKBA in Experimental Autoimmune Encephalomyelitis (EAE), as an animal model of MS. Following EAE induction in female C57BL/6J mice, animals were treated with AKBA and the levels of different serum inflammatory mediators, as well as motor functions, myelination, and inflammatory cell infiltration were assessed. Our results revealed that the application of AKBA alleviated EAE clinical severity, and suppressed inflammation, demyelination, leukocyte infiltration, and gliosis in EAE mice. Our findings suggest that the therapeutic effects of AKBA are likely a consequence of its neuroprotective and anti-inflammatory properties. The beneficial effects of AKBA may therefore provide new insights in various neuroinflammatory diseases such as MS and thereby could serve as a potential treatment candidate.

PD-L1+ Lymphocytes Are Associated with CD4+, Foxp3+CD4+, IL17+CD4+ T Cells and Subtypes of Macrophages in Resected Early-Stage Non-Small Cell Lung Cancer

The non-canonical PD-L1 pathway revealed that programmed-death ligand 1 (PD-L1) expression in immune cells also plays a crucial role in immune response. Moreover, immune cell distribution in a tumour microenvironment (TME) is pivotal for tumour genesis. However, the results remain controversial and further research is needed. Distribution of PD-L1-positive (PD-L1+) tumour-infiltrating lymphocytes in the context of TME was assessed in 72 archival I-III stage surgically resected NSCLC tumour specimens. Predominant PD-L1+ lymphocyte distribution in the tumour stroma, compared to islets, was found (p = 0.01). Higher PD-L1+ lymphocyte infiltration was detected in smokers due to their predominance in the stroma. High PD-L1+ lymphocyte infiltration in tumour stroma was more common in tumours with higher CD4+ T cell infiltration in islets and stroma, Foxp3+CD4+ T cell infiltration in islets and lover M1 macrophage infiltration in the stroma (p = 0.034, p = 0.034, p = 0.005 and p = 0.034 respectively). Meanwhile, high PD-L1+ lymphocyte infiltration in islets was predominantly found in tumours with high levels of IL-17A+CD4+ T cells in islets and Foxp3+CD4+ T cells in islets and stroma (p = 0.032, p = 0.009 and p = 0.034, respectively). Significant correlations between PD-L1+ lymphocytes and tumour-infiltrating CD4+, Foxp3+CD4+, IL-17A+CD4+ T cells and M2 macrophages were found. An analysis of the tumour-immune phenotype revealed a significant association between PD-L1 expression and IL17+CD4+ and Foxp3+CD4+ immune phenotypes. PD-L1+ lymphocytes are associated with the distribution of CD4+, Foxp3+CD4+, IL17A+CD4+ T cells, M1 and M2 macrophages in TME of resected NSCLC.

Evaluating the Serum Level of ACTH and Investigating the Expression of miR-26a, miR-34a, miR-155-5p, and miR-146a in the Peripheral Blood Cells of Multiple Sclerosis Patients

Multiple sclerosis (MS) is an inflammatory and neurodegenerative disorder affecting white and gray matter. This study aimed to investigate the association between clinical outcomes in MS patients and the levels of certain molecules in their serum, including ACTH, IL-17, and specific miRNAs: miR-26a, miR-34a, miR-155-5p, and miR-146a. Fifty healthy people and 75 blood samples from MS patients were selected. MS patients had higher expression levels of IL-17, miR-26a, miR-34a, and miR-146a compared to healthy individuals (p < 0.0001). There was no significant difference in miR-155-5p expression between the two groups (p = 0.203). MS patients also had higher serum levels of ACTH compared to the normal population (p < 0.0001). In MS patients, there was a negative correlation between IL-17 and miR-155-5p expression levels (p = 0.048, r =  - 0.229). Similarly, a significant negative correlation was observed between ACTH and miR-155-5p in the control group (p = 0.044, r =  - 0.286). The study's analysis revealed no significant difference in the expression of miR-155-5p between MS patients and normal individuals; the study's examination revealed that the expression level of IL-17, miR-26a, miR-34a, and miR-146a was higher in MS patients than in normal individuals.

Hub genes, a diagnostic model, and immune infiltration based on ferroptosis-linked genes in schizophrenia

Background

Schizophrenia (SCZ) is a prevalent and serious mental disorder, and the exact pathophysiology of this condition is not fully understood. In previous studies, it has been proven that ferroprotein levels are high in SCZ. It has also been shown that this inflammatory response may modify fibromodulin. Accumulating evidence indicates a strong link between metabolism and ferroptosis. Therefore, the present study aims to identify ferroptosis-linked hub genes to further investigate the role that ferroptosis plays in the development of SCZ.

Material and methods

From the GEO database, four microarray data sets on SCZ (GSE53987, GSE38481, GSE18312, and GSE38484) and ferroptosis-linked genes were extracted. Using the prefrontal cortex expression matrix of SCZ patients and healthy individuals as the control group from GSE53987, weighted gene co-expression network analysis (WGCNA) was performed to discover SCZ-linked module genes. From the feed, genes associated with ferroptosis were retrieved. The intersection of the module and ferroptosis-linked genes was done to obtain the hub genes. Then, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses, and Gene Set Enrichment Analysis (GSEA) were conducted. The SCZ diagnostic model was established using logistic regression, and the GSE38481, GSE18312, and GSE38484 data sets were used to validate the model. Finally, hub genes linked to immune infiltration were examined.

Results

A total of 13 SCZ module genes and 7 hub genes linked to ferroptosis were obtained: DECR1, GJA1, EFN2L2, PSAT1, SLC7A11, SOX2, and YAP1. The GO/KEGG/GSEA study indicated that these hub genes were predominantly enriched in mitochondria and lipid metabolism, oxidative stress, immunological inflammation, ferroptosis, Hippo signaling pathway, AMP-activated protein kinase pathway, and other associated biological processes. The diagnostic model created using these hub genes was further confirmed using the data sets of three blood samples from patients with SCZ. The immune infiltration data showed that immune cell dysfunction enhanced ferroptosis and triggered SCZ.

Conclusion

In this study, seven critical genes that are strongly associated with ferroptosis in patients with SCZ were discovered, a valid clinical diagnostic model was built, and a novel therapeutic target for the treatment of SCZ was identified by the investigation of immune infiltration.

Long-Term Accumulation of T Cytotoxic 1, T Cytotoxic 17, and T Cytotoxic 17/1 Cells in the Brain Contributes to Microglia-Mediated Chronic Neuroinflammation After Ischemic Stroke

Post-stroke neuroinflammation affects the damage and recovery of neurological functions. T cells including CD8+ T cells were present in the ipsilateral hemisphere in the subacute and late phases of ischemic stroke. However, the potential roles of CD8+ T cell subsets in the progression of neuroinflammation have not been characterized. In the current mouse transient middle cerebral artery occlusion model, we investigated the existence of CD8+ T cell subsets in the ipsilateral hemisphere in the subacute and late phases of stroke. We found that ipsilateral CD8+ T cells were present on post-stroke day 3 and increased on post-stroke day 30. The day-3 ipsilateral CD8+ T cells predominantly produced interferon-γ (IFN-γ), while the day-30 ipsilateral CD8+ T cells co-expressed IFN-γ and interleukin-17A (IL-17A). In addition, evaluation of cytokines and transcription factors of the day-30 ipsilateral CD8+ T cells revealed the presence of T cytotoxic 1 (Tc1), T cytotoxic 17 (Tc17), and T cytotoxic 17/1 (Tc17/1) cells. Furthermore, based on the expression of a series of chemokine/cytokine receptors, viable ipsilateral Tc1, Tc17, and Tc17.1 cells were identified and enriched from the day-30 ipsilateral CD8+ T cells, respectively. Co-culture of microglia with ipsilateral Tc1, Tc17, or Tc17.1 cells indicated that the three CD8+ T cell subsets up-regulated the expression of pro-inflammatory mediators by microglia, with Tc17.1 cells being the most potent cell in doing so. Collectively, this study sheds light on the contributions of Tc1, Tc17, and Tc17.1 cells to long-term neuroinflammation after ischemic stroke.

Immunophenotyping in routine clinical practice for predicting treatment response and adverse events in patients with MS

Background

Recent studies proposed cellular immunoprofiling as a surrogate for predicting treatment response and/or stratifying the occurrence of adverse events (AEs) in persons with multiple sclerosis (pwMS). However, applicability in real-world circumstances is not sufficiently addressed.

Objective

We aimed to explore whether standard routine clinical leukocyte phenotyping before treatment initiation could help stratify patients according to treatment response or AEs in a real-world MS cohort.

Methods

In this retrospective study, 150 pwMS were included, who had been newly initiated on a disease-modifying drug (DMD) and had been assessed for standard immunophenotyping before DMD initiation (baseline) and at least once during the following year. Multivariate models were used to assess an association of immune subsets and the association between immune cell profiles regarding treatment response and AEs.

Results

We found that the composition of T cell subsets was associated with relapse activity, as an increased proportion of CD8+ lymphocytes at baseline indicated a higher likelihood of subsequent relapse (about 9% per 1% increase in CD8+ proportion of all CD3+ cells). This was particularly driven by patients receiving anti-CD20 therapy, where also EDSS worsening was associated with a higher number of CD8+ cells at baseline (3% increase per 10 cells). In the overall cohort, an increase in the proportion of NK cells was associated with a higher risk of EDSS worsening (5% per 1% increase). Occurrence of AEs was associated with a higher percentage of T cells and a lower number of percentual NKT cells at baseline.

Conclusion

Immune cell profiles are associated with treatment response and the occurrence of AEs in pwMS. Hence, immunophenotyping may serve as a valuable biomarker to enable individually tailored treatment strategies in pwMS.

Regulation of immunomodulatory networks by Nrf2-activation in immune cells: Redox control and therapeutic potential in inflammatory diseases

Inflammatory diseases present a serious health challenge due to their widespread prevalence and the severe impact on patients' lives. In the quest to alleviate the burden of these diseases, nuclear factor erythroid 2-related factor 2 (Nrf2) has emerged as a pivotal player. As a transcription factor intimately involved in cellular defense against metabolic and oxidative stress, Nrf2's role in modulating the inflammatory responses of immune cells has garnered significant attention. Recent findings suggest that Nrf2's ability to alter the redox status of cells underlies its regulatory effects on immune responses. Our review delves into preclinical and clinical evidence that underscores the complex influence of Nrf2 activators on immune cell phenotypes, particularly in the inflammatory milieu. By offering a detailed analysis of Nrf2's role in different immune cell populations, we cast light on the potential of Nrf2 activators in shaping the immune response towards a more regulated state, mitigating the adverse effects of inflammation through modeling redox status of immune cells. Furthermore, we explore the innovative use of nanoencapsulation techniques that enhance the delivery and efficacy of Nrf2 activators, potentially advancing the treatment strategies for inflammatory ailments. We hope this review will stimulate the development and expansion of Nrf2-targeted treatments that could substantially improve outcomes for patients suffering from a broad range of inflammatory diseases.

Role of autoreactive Tc17 cells in the pathogenesis of experimental autoimmune encephalomyelitis

Background

The pathogenesis of multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE—an animal model of MS) is primarily mediated by T cells. However, recent studies have only focused on interleukin (IL)‐17‐secreting CD4+ T‐helper cells, also known as Th17 cells. This study aimed to compare Th17 cells and IL‐17‐secreting CD8+ T‐cytotoxic cells (Tc17) in the context of MS/EAE.

Methods

Female C57BL/6 mice were immunized with myelin oligodendrocyte glycoprotein peptides 35–55 (MOG35–55), pertussis toxin, and complete Freund's adjuvant to establish the EAE animal model. T cells were isolated from the spleen (12–14 days postimmunization). CD4+ and CD8+ T cells were purified using isolation kit and then differentiated into Th17 and Tc17, respectively, using MOG35–55 and IL‐23. The secretion levels of interferon‐γ (IFN‐γ) and IL‐17 were measured via enzyme‐linked immunosorbent assay using cultured CD4+ and CD8+ T cell supernatants. The pathogenicity of Tc17 and Th17 cells was assessed through adoptive transfer (tEAE), with the clinical course assessed using an EAE score (0–5). Hematoxylin and eosin as well as Luxol fast blue staining were used to examine the spinal cord. Purified CD8+ CD3+ and CD4+ CD3+ cells differentiated into Tc17 and Th17 cells, respectively, were stimulated with MOG35–55 peptide for proliferation assays.

Results

The results showed that Tc17 cells (15,951 ± 1985 vs. 55,709 ± 4196 cpm; p < 0.050) exhibited a weaker response to highest dose (20 μg/mL) MOG35–55 than Th17 cells. However, this response was not dependent on Th17 cells. After the 48 h stimulation, at the highest dose (20 μg/mL) of MOG35–55. Tc17 cells secreted lower levels of IFN‐γ (280.00 ± 15.00 vs. 556.67 ± 15.28 pg/mL, p < 0.050) and IL‐17 (102.67 ± 5.86 pg/mL vs. 288.33 ± 12.58 pg/mL; p < 0.050) than Th17 cells. Similar patterns were observed for IFN‐γ secretion at 96 and 144 h. Furthermore, Tc17 cell‐induced tEAE mice exhibited similar EAE scores to Th17 cell‐induced tEAE mice and also showed similar inflammation and demyelination.

Conclusion

The degree of pathogenicity of Tc17 cells in EAE is lower than that of Th17 cells. Future investigation on different immune cells and EAE models is warranted to determine the mechanisms underlying MS.

Miltefosine reduces coxsackievirus B3 lethality of mice with enhanced STAT3 activation

Coxsackievirus B3 (CVB3), one serotype of enteroviruses, can induce fatal myocarditis and hepatitis in neonates, but both treatment and vaccine are unavailable. Few reports tested antivirals to reduce CVB3. Several antivirals were developed against other enterovirus serotypes, but these antivirals failed in clinical trials due to side effects and drug resistance. Repurposing of clinical drugs targeting cellular factors, which enhance viral replication, may be another option. Parasite and cancer studies showed that the cellular protein kinase B (Akt) decreases interferon (IFN), apoptosis, and interleukin (IL)-6-induced STAT3 responses, which suppress CVB3 replication. Furthermore, miltefosine, the Akt inhibitor used in the clinic for parasite infections, enhances IL-6, IFN, and apoptosis responses in treated patients, suggesting that miltefosine could be the potential antiviral for CVB3. This study was therefore designated to test the antiviral effects of miltefosine against CVB3 in vitro and especially, in mice, as few studies test miltefosine in vitro, but not in vivo. In vitro results showed that miltefosine inhibited viral replication with enhanced activation of the cellular transcription factor, STAT3, which is reported to reduce CVB3 both in vitro and in mice. Notably, STAT3 knockdown abolished the anti-CVB3 activity of miltefosine in vitro. Mouse studies demonstrated that miltefosine pretreatment reduced CVB3 lethality of mice with decreased virus loads, organ damage, and apoptosis, but enhanced STAT3 activation. Miltefosine could be prophylaxis for CVB3 by targeting Akt to enhance STAT3 activation in the mechanism, which is independent of IFN responses and hardly reported in pathogen infections.

Mitochondrial and metabolic dysfunction of peripheral immune cells in multiple sclerosis

Multiple sclerosis (MS) is a chronic autoimmune disorder characterized by the infiltration of inflammatory cells and demyelination of nerves. Mitochondrial dysfunction has been implicated in the pathogenesis of MS, as studies have shown abnormalities in mitochondrial activities, metabolism, mitochondrial DNA (mtDNA) levels, and mitochondrial morphology in immune cells of individuals with MS. The presence of mitochondrial dysfunctions in immune cells contributes to immunological dysregulation and neurodegeneration in MS. This review provided a comprehensive overview of mitochondrial dysfunction in immune cells associated with MS, focusing on the potential consequences of mitochondrial metabolic reprogramming on immune function. Current challenges and future directions in the field of immune-metabolic MS and its potential as a therapeutic target were also discussed.

Dual-targeting nanotheranostics for MRI-guided enhanced chemodynamic therapy of hepatoma via regulating the tumor microenvironment

Chemodynamic therapy (CDT), as a reactive oxygen species (ROS)-based therapeutic modality, has attracted much attention in recent years. However, the insufficient therapeutic effect of CDT is due to the antioxidant system in the tumor microenvironment, such as high levels of glutathione (GSH). In this study, we developed a biological/physical dual-targeting nanotheranostic agent (relaxation rate, r1: 6.3 mM-1 s-1 and r2: 13.11 mM-1 s-1) for enhanced CDT of SMCC-7721 tumors. This nanotheranostic agent is composed of a homologous tumor cell membrane (TCM), magnetic ferric oxide, and manganese oxide and is denoted as FM@TCM nanoparticles (NPs). A favorable effect of in vitro CDT on SMCC-7721 cells (IC50: 20 μg mL-1) is demonstrated, attributed to the Fenton reaction and oxidative stress resulting from the reduction of the GSH level. In vivo T1/T2 magnetic resonance imaging (MRI) confirms that the tumor accumulation of FM@TCM NPs is promoted by concurrent bioactive targeting of the homologous TCM and physico-magnetic targeting of tumor tissues with an external magnetic field. Impressive chemodynamic therapeutic effects on SMCC-7721 tumors are demonstrated through the catalysis of endogenous hydrogen peroxide and depletion of GSH to generate high levels of ROS. Dual-targeting FM@TCM NPs inhibit SMCC-7721 tumor growth (∼90.9%) in vivo without any biotoxicity. This nanotheranostic agent has great potential for use in MRI-guided CDT.

Neuroprotective effects of dimethyl fumarate against manic-like behavior induced by ketamine in rats

Medications for treating bipolar disorder (BD) are limited and can cause side effects if used chronically. Therefore, efforts are being made to use new agents in the control and treatment of BD. Considering the antioxidant and anti-inflammatory effects of dimethyl fumarate (DMF), this study was performed to examine the role of DMF on ketamine (KET)-induced manic-like behavior (MLB) in rats. Forty-eight rats were randomly divided into eight groups, including three groups of healthy rats: normal, lithium chloride (LiCl) (45 mg/kg, p.o.), and DMF (60 mg/kg, p.o.), and five groups of MLB rats: control, LiCl, and DMF (15, 30, and 60 mg/kg, p.o.), which received KET at a dose of 25 mg/kg, i.p. The levels of total sulfhydryl groups (total SH), thiobarbituric acid reactive substances (TBARS), nitric oxide (NO), and tumor necrosis factor-alpha (TNF-α), as well as the activity of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the prefrontal cortex (PFC) and hippocampus (HPC), were measured. DMF prevented hyperlocomotion (HLM) induced by KET. It was found that DMF could inhibit the increase in the levels of TBARS, NO, and TNF-α in the HPC and PFC of the brain. Furthermore, by examining the amount of total SH and the activity of SOD, GPx, and CAT, it was found that DMF could prevent the reduction of the level of each of them in the brain HPC and PFC. DMF pretreatment improved the symptoms of the KET model of mania by reducing HLM, oxidative stress, and modulating inflammation.

CD8 T-cell subsets: heterogeneity, functions, and therapeutic potential

CD8 T cells play crucial roles in immune surveillance and defense against infections and cancer. After encountering antigenic stimulation, naïve CD8 T cells differentiate and acquire effector functions, enabling them to eliminate infected or malignant cells. Traditionally, cytotoxic T cells, characterized by their ability to produce effector cytokines and release cytotoxic granules to directly kill target cells, have been recognized as the constituents of the predominant effector T-cell subset. However, emerging evidence suggests distinct subsets of effector CD8 T cells that each exhibit unique effector functions and therapeutic potential. This review highlights recent advancements in our understanding of CD8 T-cell subsets and the contributions of these cells to various disease pathologies. Understanding the diverse roles and functions of effector CD8 T-cell subsets is crucial to discern the complex dynamics of immune responses in different disease settings. Furthermore, the development of immunotherapeutic approaches that specifically target and regulate the function of distinct CD8 T-cell subsets holds great promise for precision medicine.

Ellagic acid effects on disease severity, levels of cytokines and T-bet, RORγt, and GATA3 genes expression in multiple sclerosis patients: a multicentral-triple blind randomized clinical trial

BACKGROUND

Multiple sclerosis (MS) is a chronic autoimmune disease. Ellagic acid is a natural polyphenol and affects the fate of neurons through its anti-inflammatory and antioxidant properties. The present study aimed to investigate ellagic acid effects on disease severity, the expression of involved genes in the pathogenesis of MS, and the levels of related cytokines.

METHODS

The present study was a triple-blind clinical trial. Eligible patients were randomly assigned to two groups: Ellagic acid (25 subjects) for 12 weeks, receiving 180 mg of Ellagic acid (Axenic, Australia) and the control group (25 subjects) receiving a placebo, before the main meals. Before and after the study, the data including general information, foods intake, physical activity, anthropometric data, expanded disability status scale (EDSS), general health questionnaire (GHQ) and pain rating index (PRI), fatigue severity scale (FSS) were assessed, as well as serum levels of interferon-gamma (IFNγ), interleukin-17 (IL-17), interleukin-4 (IL-4) and transforming growth factor-beta (TGF-β), nitric-oxide (NO) using enzyme-linked immunoassay (ELISA) method and expression of T-box transcription factor (Tbet), GATA Binding Protein 3 (GATA3), retinoic acid-related orphan receptor-γt (RORγt) and Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were determined using Real-Time Quantitative Reverse Transcription PCR (RT-qPCR) method.

FINDINGS

Ellagic acid supplementation led to a reduction in IFNγ, IL-17, NO and increased IL-4 in the ellagic acid group, however in the placebo group no such changes were observed (-24.52 ± 3.79 vs. -0.05 ± 0.02, p < 0.01; -5.37 ± 0.92 vs. 2.03 ± 1.03, p < 0.01; -18.03 ± 1.02 vs. -0.06 ± 0.05, p < 0.01, 14.69 ± 0.47 vs. -0.09 ± 0.14, p < 0.01, respectively). Ellagic acid supplementation had no effect on TGF-β in any of the study groups (p > 0.05). Also, the Tbet and RORγt genes expression decreased, and the GATA3 gene expression in the group receiving ellagic acid compared to control group significantly increased (0.52 ± 0.29 vs. 1.51 ± 0.18, p < 0.01, 0.49 ± 0.18 vs. 1.38 ± 0.14, p < 0.01, 1.71 ± 0.39 vs. 0.27 ± 0.10, p < 0.01). Also, ellagic acid supplementation led to significant decrease in EDSS, FSS and GHQ scores (p < 0.05), and no significant changes observed in PRI score (p > 0.05).

CONCLUSION

Ellagic acid supplementation can improve the health status of MS patients by reduction of the inflammatory cytokines and Tbet and RORγt gene expression, and increment of anti-inflammatory cytokines and GATA3 gene expression.Clinical trial registration: (https://en.irct.ir/trial/53020), IRCT20120415009472N22.

IL-17A-producing CD8+ T cells promote PDAC via induction of inflammatory cancer-associated fibroblasts

OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) is characterised by an abundant desmoplastic stroma composed of cancer-associated fibroblasts (CAF) and interspersed immune cells. A non-canonical CD8+ T-cell subpopulation producing IL-17A (Tc17) promotes autoimmunity and has been identified in tumours. Here, we evaluated the Tc17 role in PDAC.

DESIGN

Infiltration of Tc17 cells in PDAC tissue was correlated with patient overall survival and tumour stage. Wild-type (WT) or Il17ra-/- quiescent pancreatic stellate cells (qPSC) were exposed to conditional media obtained from Tc17 cells (Tc17-CM); moreover, co-culture of Tc17-CM-induced inflammatory (i)CAF (Tc17-iCAF) with tumour cells was performed. IL-17A/F-, IL-17RA-, RAG1-deficient and Foxn1nu/nu mice were used to study the Tc17 role in subcutaneous and orthotopic PDAC mouse models.

RESULTS

Increased abundance of Tc17 cells highly correlated with reduced survival and advanced tumour stage in PDAC. Tc17-CM induced iCAF differentiation as assessed by the expression of iCAF-associated genes via synergism of IL-17A and TNF. Accordingly, IL-17RA controlled the responsiveness of qPSC to Tc17-CM. Pancreatic tumour cells co-cultured with Tc17-iCAF displayed enhanced proliferation and increased expression of genes implicated in proliferation, metabolism and protection from apoptosis. Tc17-iCAF accelerated growth of mouse and human tumours in Rag1-/- and Foxn1nu/nu mice, respectively. Finally, Il17ra-expressed by fibroblasts was required for Tc17-driven tumour growth in vivo.

CONCLUSIONS

We identified Tc17 as a novel protumourigenic CD8+ T-cell subtype in PDAC, which accelerated tumour growth via IL-17RA-dependent stroma modification. We described a crosstalk between three cell types, Tc17, fibroblasts and tumour cells, promoting PDAC progression, which resulted in poor prognosis for patients.

Friend or Foe - Tc17 cell generation and current evidence for their importance in human disease

The term Tc17 cells refers to interleukin 17 (IL-17)-producing CD8+ T cells. While IL-17 is an important mediator of mucosal defense, it is also centrally involved in driving the inflammatory response in immune-mediated diseases, such as psoriasis, multiple sclerosis, and inflammatory bowel disease. In this review, we aim to gather the current knowledge on the phenotypic and transcriptional profile, the in vitro and in vivo generation of Tc17 cells, and the evidence pointing towards a relevant role of Tc17 cells in human diseases such as infectious diseases, cancer, and immune-mediated diseases.

Implications of immunometabolism for smouldering MS pathology and therapy

Clinical symptom worsening in patients with multiple sclerosis (MS) is driven by inflammation compartmentalized within the CNS, which results in chronic neuronal damage owing to insufficient repair mechanisms. The term 'smouldering inflammation' summarizes the biological aspects underlying this chronic, non-relapsing and immune-mediated mechanism of disease progression. Smouldering inflammation is likely to be shaped and sustained by local factors in the CNS that account for the persistence of this inflammatory response and explain why current treatments for MS do not sufficiently target this process. Local factors that affect the metabolic properties of glial cells and neurons include cytokines, pH value, lactate levels and nutrient availability. This Review summarizes current knowledge of the local inflammatory microenvironment in smouldering inflammation and how it interacts with the metabolism of tissue-resident immune cells, thereby promoting inflammatory niches within the CNS. The discussion highlights environmental and lifestyle factors that are increasingly recognized as capable of altering immune cell metabolism and potentially responsible for smouldering pathology in the CNS. Currently approved MS therapies that target metabolic pathways are also discussed, along with their potential for preventing the processes that contribute to smouldering inflammation and thereby to progressive neurodegenerative damage in MS.

Dimethyl fumarate-related immune and transcriptional signature is associated with clinical response in multiple sclerosis-treated patients

Background and objective

Dimethyl fumarate (DMF) is an immunomodulatory drug approved for the therapy of multiple sclerosis (MS). The identification of response biomarkers to DMF is a necessity in the clinical practice. With this aim, we studied the immunophenotypic and transcriptomic changes produced by DMF in peripheral blood mononuclear cells (PBMCs) and its association with clinical response.

Material and methods

PBMCs were obtained from 22 RRMS patients at baseline and 12 months of DMF treatment. Lymphocyte and monocyte subsets, and gene expression were assessed by flow cytometry and next-generation RNA sequencing, respectively. Clinical response was evaluated using the composite measure "no evidence of disease activity" NEDA-3 or "evidence of disease activity" EDA-3 at 2 years, classifying patients into responders (n=15) or non-responders (n=7), respectively.

Results

In the whole cohort, DMF produced a decrease in effector (TEM) and central (TCM) memory T cells in both the CD4+ and CD8+ compartments, followed by an increase in CD4+ naïve T cells. Responder patients presented a greater decrease in TEM lymphocytes. In addition, responder patients showed an increase in NK cells and were resistant to the decrease in the intermediate monocytes shown by non-responders. Responder patients also presented differences in 3 subpopulations (NK bright, NK dim and CD8 TCM) at baseline and 4 subpopulations (intermediate monocytes, regulatory T cells, CD4 TCM and CD4 TEMRA) at 12 months. DMF induced a mild transcriptional effect, with only 328 differentially expressed genes (DEGs) after 12 months of treatment. The overall effect was a downregulation of pro-inflammatory genes, chemokines, and activators of the NF-kB pathway. At baseline, no DEGs were found between responders and non-responders. During DMF treatment a differential transcriptomic response was observed, with responders presenting a higher number of DEGs (902 genes) compared to non-responders (189 genes).

Conclusions

Responder patients to DMF exhibit differences in monocyte and lymphocyte subpopulations and a distinguishable transcriptomic response compared to non-responders that should be further studied for the validation of biomarkers of treatment response to DMF.

Cancer-cell-derived fumarate suppresses the anti-tumor capacity of CD8+ T cells in the tumor microenvironment

Metabolic alterations in the microenvironment significantly modulate tumor immunosensitivity, but the underlying mechanisms remain obscure. Here, we report that tumors depleted of fumarate hydratase (FH) exhibit inhibition of functional CD8⁺ T cell activation, expansion, and efficacy, with enhanced malignant proliferative capacity. Mechanistically, FH depletion in tumor cells accumulates fumarate in the tumor interstitial fluid, and increased fumarate can directly succinate ZAP70 at C96 and C102 and abrogate its activity in infiltrating CD8⁺ T cells, resulting in suppressed CD8⁺ T cell activation and anti-tumor immune responses in vitro and in vivo. Additionally, fumarate depletion by increasing FH expression strongly enhances the anti-tumor efficacy of anti-CD19 CAR T cells. Thus, these findings demonstrate a role for fumarate in controlling TCR signaling and suggest that fumarate accumulation in the tumor microenvironment (TME) is a metabolic barrier to CD8⁺ T cell anti-tumor function. And potentially, fumarate depletion could be an important strategy for tumor immunotherapy.

Beyond Antioxidation: Keap1-Nrf2 in the Development and Effector Functions of Adaptive Immune Cells

Ubiquitously expressed in mammalian cells, the Kelch-like ECH-associated protein 1 (Keap1)-NF erythroid 2-related factor 2 (Nrf2) complex forms the evolutionarily conserved antioxidation system to tackle oxidative stress caused by reactive oxygen species. Reactive oxygen species, generated as byproducts of cellular metabolism, were identified as essential second messengers for T cell signaling, activation, and effector responses. Apart from its traditional role as an antioxidant, a growing body of evidence indicates that Nrf2, tightly regulated by Keap1, modulates immune responses and regulates cellular metabolism. Newer functions of Keap1 and Nrf2 in immune cell activation and function, as well as their role in inflammatory diseases such as sepsis, inflammatory bowel disease, and multiple sclerosis, are emerging. In this review, we highlight recent findings about the influence of Keap1 and Nrf2 in the development and effector functions of adaptive immune cells, that is, T cells and B cells, and discuss the knowledge gaps in our understanding. We also summarize the research potential and targetability of Nrf2 for treating immune pathologies.

Characterization of pathogenic synovial IL-17A-producing CD8+ T cell subsets in collagen-induced arthritis

Using a murine collagen-induced arthritis model, we characterized the heterogeneity of synovial CD8⁺ T cells based on the expression of chemokine receptors, cytokines, and nuclear transcription factors. Four subsets, i.e. CXCR3^-CCR4^- cells, CXCR3⁺CCR4^- cells, CXCR3⁺CCR4⁺ cells, and CXCR3^-CCR4⁺ cells, were present in synovial CD8⁺CD62L^-CCR6⁺IL-23R⁺CCR10^- T cells. CXCR3^-CCR4^- cells belonged to exhausted CD8⁺ T cells. CXCR3⁺CCR4^- cells were Tc17.1 cells expressing both IL-17A and IFN-γ. CXCR3⁺CCR4⁺ cells were transitional Tc17.1 cells expressing IL-17A but lower IFN-γ, and CXCR3^-CCR4⁺ cells were Tc17 cells expressing IL-17A but no IFN-γ. Transitional Tc17.1 cells can differentiate into Tc17.1 cells in vitro under the instruction of IL-12. Tc17.1 cells and transitional Tc17.1 cells strongly induced the expression of pro-inflammatory mediators in synovial fibroblasts, whereas Tc17 cells were less potent in doing so. IFN-γ was involved in the higher pathogenicity of Tc17.1 cells and transitional Tc17.1 cells on synovial fibroblasts. This study expands the understanding of Tc17 biology by unveiling the phenotypic and functional heterogeneity of synovial IL-17A-expressing CD8⁺ T cells. These heterogeneous IL-17A-expressing CD8⁺ T cells could be novel therapeutic targets in future arthritis treatment.

The impact of the gut microbiome on extra-intestinal autoimmune diseases

The prevalence of autoimmune diseases (ADs) worldwide has rapidly increased over the past few decades. Thus, in addition to the classical risk factors for ADs, such as genetic polymorphisms, infections and smoking, environmental triggers have been considered. Recent sequencing-based approaches have revealed that patients with extra-intestinal ADs, such as multiple sclerosis, rheumatoid arthritis, type 1 diabetes and systemic lupus erythematosus, have distinct gut microbiota compositions compared to healthy controls. Faecal microbiota transplantation or inoculation with specific microbes in animal models of ADs support the hypothesis that alterations of gut microbiota influence autoimmune responses and disease outcome. Here, we describe the compositional and functional changes in the gut microbiota in patients with extra-intestinal AD and discuss how the gut microbiota affects immunity. Moreover, we examine how the gut microbiota might be modulated in patients with ADs as a potential preventive or therapeutic approach.

GM-CSF+ Tc17 cells are required to bolster vaccine immunity against lethal fungal pneumonia without causing overt pathology

GM-CSF co-expressing T17 cells instigate pathologic inflammation during autoimmune disorders, but their function in immunity to infections is unclear. Here, we demonstrate the role of GM-CSF⁺Tc17 cells for vaccine immunity against lethal fungal pneumonia and the cytokine requirements for their induction and memory homeostasis. Vaccine-induced GM-CSF⁺ Tc17 cells are necessary to bolster pulmonary fungal immunity without inflating pathology. Although GM-CSF expressing Tc17 cells preferentially elevate during the memory phase, their phenotypic attributes strongly suggest they are more like Tc17 cells than IFNγ-producing Tc1 cells. IL-1 and IL-23, but not GM-CSF, are necessary to elicit GM-CSF⁺Tc17 cells following vaccination. IL-23 is dispensable for memory Tc17 and GM-CSF⁺ Tc17 cell maintenance, but recall responses of effector or memory Tc17 cells in the lung require it. Our study reveals the beneficial, nonpathological role of GM-CSF⁺ Tc17 cells during fungal vaccine immunity.

GM-CSF⁺ and IL-17A⁺ lineages of T cells are instrumental in controlling many fungal and bacterial infections and implicated in autoimmune pathology, host-microbial interactions at the mucosal surfaces, and neuro-immune nexus. Mudalagiriyappa et al. show that GM-CSF expressing Tc17 cells are necessary for mediating fungal vaccine immunity without augmenting pathology.

Tc17 cells in autoimmune diseases

Multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE), a pathologically similar disease used to model MS in rodents, are typical CD4+ T cell-dominated autoimmune diseases. CD4+ interleukin (IL)17+ T cells (Th17 cells) have been well studied and have shown that they play a critical role in the pathogenesis of MS/EAE. However, studies have suggested that CD8+IL17+ T cells (Tc17 cells) have a similar phenotype and cytokine and transcription factor profiles to those of Th17 cells and have been found to be crucial in the pathogenesis of autoimmune diseases, including MS/EAE, psoriasis, type I diabetes, rheumatoid arthritis, and systemic lupus erythematosus. However, the evidence for this is indirect and insufficient. Therefore, we searched for related publications and attempted to summarize the current knowledge on the role of Tc17 cells in the pathogenesis of MS/EAE, as well as in the pathogenesis of other autoimmune diseases, and to find out whether Tc17 cells or Th17 cells play a more critical role in autoimmune disease, especially in MS and EAE pathogenesis, or whether the interaction between these two cell types plays a critical role in the development of the disease.

High-dimensional immune profiling identifies a biomarker to monitor dimethyl fumarate response in multiple sclerosis

Dimethyl fumarate (DMF) is an immunomodulatory treatment for multiple sclerosis (MS). Despite its wide clinical use, the mechanisms underlying clinical response are not understood. This study aimed to reveal immune markers of therapeutic response to DMF treatment in MS. For this purpose, we prospectively collected peripheral blood mononuclear cells (PBMCs) from a highly characterized cohort of 44 individuals with MS before and at 12 and 48 wk of DMF treatment. Single cells were profiled using high-dimensional mass cytometry. To capture the heterogeneity of different immune subsets, we adopted a bioinformatic multipanel approach that allowed cell population-cluster assignment of more than 50 different parameters, including lineage and activation markers as well as chemokine receptors and cytokines. Data were further analyzed in a semiunbiased fashion implementing a supervised representation learning approach to capture subtle longitudinal immune changes characteristic for therapy response. With this approach, we identified a population of memory T helper cells expressing high levels of neuroinflammatory cytokines (granulocyte-macrophage colony-stimulating factor [GM-CSF], interferon γ [IFNγ]) as well as CXCR3, whose abundance correlated with treatment response. Using spectral flow cytometry, we confirmed these findings in a second cohort of patients. Serum neurofilament light-chain levels confirmed the correlation of this immune cell signature with axonal damage. The identified cell population is expanded in peripheral blood under natalizumab treatment, substantiating a specific role in treatment response. We propose that depletion of GM-CSF-, IFNγ-, and CXCR3-expressing T helper cells is the main mechanism of action of DMF and allows monitoring of treatment response.

High-dimensional profiling reveals Tc17 cell enrichment in active Crohn's disease and identifies a potentially targetable signature

The immune-pathology in Crohn’s disease is linked to dysregulated CD4+ T cell responses biased towards pathogenic TH17 cells. However, the role of CD8+ T cells able to produce IL-17 (Tc17 cells) remains unclear. Here we characterize the peripheral blood and intestinal tissue of Crohn’s disease patients (n = 61) with flow and mass cytometry and reveal a strong increase of Tc17 cells in active disease, mainly due to induction of conventional T cells. Mass cytometry shows that Tc17 cells express a distinct immune signature (CD6^high, CD39, CD69, PD-1, CD27^low) which was validated in an independent patient cohort. This signature stratifies patients into groups with distinct flare-free survival associated with differential CD6 expression. Targeting of CD6 in vitro reduces IL-17, IFN-γ and TNF production. These results identify a distinct Tc17 cell population in Crohn’s disease with proinflammatory features linked to disease activity. The Tc17 signature informs clinical outcomes and may guide personalized treatment decisions.

The T cell compartment in patients with Crohn's disease is dysregulated. Here the authors use cytometric profiling to reveal an enrichment of distinct Tc17 cells during active Crohn's disease and may suggest CD6 as a potential target for therapeutic studies.

MicroRNAs as T Lymphocyte Regulators in Multiple Sclerosis

MicroRNA (miRNA) is a class of endogenous non-coding small RNA with regulatory activities, which generally regulates the expression of target genes at the post-transcriptional level. Multiple Sclerosis (MS) is thought to be an autoimmune-mediated chronic inflammatory demyelinating disease of the central nervous system (CNS) that typically affect young adults. T lymphocytes play an important role in the pathogenesis of MS, and studies have suggested that miRNAs are involved in regulating the proliferation, differentiation, and functional maintenance of T lymphocytes in MS. Dysregulated expression of miRNAs may lead to the differentiation balance and dysfunction of T lymphocytes, and they are thus involved in the occurrence and development of MS. In addition, some specific miRNAs, such as miR-155 and miR-326, may have potential diagnostic values for MS or be useful for discriminating subtypes of MS. Moreover, miRNAs may be a promising therapeutic strategy for MS by regulating T lymphocyte function. By summarizing the recent literature, we reviewed the involvement of T lymphocytes in the pathogenesis of MS, the role of miRNAs in the pathogenesis and disease progression of MS by regulating T lymphocytes, the possibility of differentially expressed miRNAs to function as biomarkers for MS diagnosis, and the therapeutic potential of miRNAs in MS by regulating T lymphocytes.

The Role of Oxidative Stress and Inflammation in X-Link Adrenoleukodystrophy

X-linked adrenoleukodystrophy (X-ALD) is an inherited disease caused by a mutation in the ABCD1 gene encoding a peroxisomal transmembrane protein. It is characterized by the accumulation of very-long-chain fatty acids (VLCFAs) in body fluids and tissues, leading to progressive demyelination and adrenal insufficiency. ALD has various phenotypes, among which the most common and severe is childhood cerebral adrenoleukodystrophy (CCALD). The pathophysiological mechanisms of ALD remain unclear, but some in vitro/in vivo research showed that VLCFA could induce oxidative stress and inflammation, leading to damage. In addition, the evidence that oxidative stress and inflammation are increased in patients with X-ALD also proves that it is a potential mechanism of brain and adrenal damage. Therefore, normalizing the redox balance becomes a critical therapeutic target. This study focuses on the possible predictors of the severity and progression of X-ALD, the potential mechanisms of pathogenesis, and the promising targeted drugs involved in oxidative stress and inflammation.

Metabolic adaptation of lymphocytes in immunity and disease

Adaptive immune responses mediated by T cells and B cells are crucial for protective immunity against pathogens and tumors. Differentiation and function of immune cells require dynamic reprogramming of cellular metabolism. Metabolic inputs, pathways, and enzymes display remarkable flexibility and heterogeneity, especially in vivo. How metabolic plasticity and adaptation dictate functional specialization of immune cells is fundamental to our understanding and therapeutic modulation of the immune system. Extensive progress has been made in characterizing the effects of metabolic networks on immune cell fate and function in discrete microenvironments or immunological contexts. In this review, we summarize how rewiring of cellular metabolism determines the outcome of adaptive immunity in vivo, with a focus on how metabolites, nutrients, and driver genes in immunometabolism instruct cellular programming and immune responses during infection, inflammation, and cancer in mice and humans. Understanding context-dependent metabolic remodeling will manifest legitimate opportunities for therapeutic intervention of human disease.

Comprehensive Assessment of Multiple Sclerosis: From Immunotherapy and Immunopathogenesis to Predictive Biomarkers

BACKGROUND & OBJECTIVE

Multiple sclerosis (MS) is an inflammatory neurological disorder that affects the central nervous system (CNS) and causes individuals to experience a variety of cognitive and physical problems. As proven by two decades of clinical experience with immunomodulatory therapies for MS, the disease progresses and relapses through several immunological pathways. New medicines aimed at remyelination and neurodegeneration are being developed; however, they need stronger evidence before being introduced into routine clinical care. The purpose of this study was a thorough assessment of MS immunopathology and predictive biomarkers.

METHODS

Immunotherapy, immunopathogenesis, and prognostic biomarkers were all parts of the search method. Only publications in English were considered for inclusion in the study. For that purpose, we went through the current state of knowledge around MS immunopathology and related biomarkers. Immunology, as well as the identification of increased inflammation as an important component of neurodegeneration, shaped our understanding of this disease aetiology. The relevant sources examined covered the years 2015-2021.

CONCLUSION

We found biomarkers in the cerebrospinal fluid and blood that might be used for the prediction and diagnosis of MS, as well as for measuring treatment response and adverse effects. Many variables, including the role of some infectious organisms and the impact of environmental and social factors, might contribute to the immunological dysfunctions seen in MS. Patients with MS may benefit from better therapy options if a better understanding of MS biomarkers and immune response mechanisms would be obtained.

The yin and yang of intracellular reactive oxygen species following T-cell activation

This scientific commentary refers to ‘Dimethyl fumarate treatment restrains the antioxidative capacity of T cells to control autoimmunity’ by Liebmann et al. (doi:10.1093/brain/awab307).

Dimethyl fumarate treatment restrains the antioxidative capacity of T cells to control autoimmunity

Dimethyl fumarate, an approved treatment for relapsing-remitting multiple sclerosis, exerts pleiotropic effects on immune cells as well as CNS resident cells.

Here, we show that dimethyl fumarate exerts a profound alteration of the metabolic profile of human CD4⁺ as well as CD8⁺ T cells and restricts their antioxidative capacities by decreasing intracellular levels of the reactive oxygen species scavenger glutathione. This causes an increase in mitochondrial reactive oxygen species levels accompanied by an enhanced mitochondrial stress response, ultimately leading to impaired mitochondrial function. Enhanced mitochondrial reactive oxygen species levels not only result in enhanced T-cell apoptosis in vitro as well as in dimethyl fumarate-treated patients, but are key for the well-known immunomodulatory effects of dimethyl fumarate both in vitro and in an animal model of multiple sclerosis, i.e. experimental autoimmune encephalomyelitis. Indeed, dimethyl fumarate immune-modulatory effects on T cells were completely abrogated by pharmacological interference of mitochondrial reactive oxygen species production.

These data shed new light on dimethyl fumarate as bona fide immune-metabolic drug that targets the intracellular stress response in activated T cells, thereby restricting mitochondrial function and energetic capacity, providing novel insight into the role of oxidative stress in modulating cellular immune responses and T cell-mediated autoimmunity.

Anti-CD52 antibody treatment in murine experimental autoimmune encephalomyelitis induces dynamic and differential modulation of innate immune cells in peripheral immune and central nervous systems

Anti‐CD52 antibody (anti‐CD52‐Ab) leads to a rapid depletion of T and B cells, followed by reconstitution of immune cells with tolerogenic characteristics. However, very little is known about its effect on innate immune cells. In this study, experimental autoimmune encephalomyelitis mice were administered murine anti‐CD52‐Ab to investigate its effect on dendritic cells and monocytes/macrophages in the periphery lymphoid organs and the central nervous system (CNS). Our data show that blood and splenic innate immune cells exhibited significantly increased expression of MHC‐II and costimulatory molecules, which was associated with increased capacity of activating antigen‐specific T cells, at first day but not three weeks after five daily treatment with anti‐CD52‐Ab in comparison with controls. In contrast to the periphery, microglia and infiltrating macrophages in the CNS exhibited reduced expression levels of MHC‐II and costimulatory molecules after antibody treatment at both time‐points investigated when compared to controls. Furthermore, the transit response of peripheral innate immune cells to anti‐CD52‐Ab treatment was also observed in the lymphocyte‐deficient SCID mice, suggesting the changes are not a direct consequence of the mass depletion of lymphocytes in the periphery. Our study demonstrates a dynamic and tissue‐specific modulation of the innate immune cells in their phenotype and function following the antibody treatment. The findings of differential modulation of the microglia and infiltrating macrophages in the CNS in comparison with the innate immune cells in the peripheral organs support the CNS‐specific beneficial effect of alemtuzumab treatment on inhibiting neuroinflammation in multiple sclerosis patients.

Development of humoral and cellular immunological memory against SARS-CoV-2 despite B cell depleting treatment in multiple sclerosis

B cell depleting therapies (BCDTs) are widely used as immunomodulating agents for autoimmune diseases such as multiple sclerosis. Their possible impact on development of immunity to severe acute respiratory syndrome virus-2 (SARS-CoV-2) has raised concerns with the coronavirus disease 2019 (COVID-19) pandemic. We here evaluated the frequency of COVID-19-like symptoms and determined immunological responses in participants of an observational trial comprising several multiple sclerosis disease modulatory drugs (COMBAT-MS; NCT03193866) and in eleven patients after vaccination, with a focus on BCDT. Almost all seropositive and 17.9% of seronegative patients on BCDT, enriched for a history of COVID-19-like symptoms, developed anti-SARS-CoV-2 T cell memory, and T cells displayed functional similarity to controls producing IFN-γ and TNF. Following vaccination, vaccine-specific humoral memory was impaired, while all patients developed a specific T cell response. These results indicate that BCDTs do not abrogate SARS-CoV-2 cellular memory and provide a possible explanation as to why the majority of patients on BCDTs recover from COVID-19.

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BCDT might blunt antibody responses after COVID-19 infection or vaccination

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Patients with no detectable B cells in the blood might still produce antibodies

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A majority of patients that do not develop antibodies still display a T cell response

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SARS-CoV-2 T-cells produce Th1 cytokines both in patients on BCDT and untreated

Serum lactate dehydrogenase level as a possible predictor of treatment preference in psoriasis

BACKGROUND

The efficacy of small molecule inhibitors for intracellular signal mediators varies among the individuals, and their mechanism of action is broad. A phosphodiesterase 4 inhibitor apremilast shows a dramatic effect on a certain proportion of psoriatic patients by modulating the cellular metabolism and regulating the production of pro-inflammatory molecules. However, it is unclear to which disease subtype this drug benefits. While psoriasis is a Th17-mediated disease, how immune cells are affected by the modulation of cellular metabolism is not fully evaluated, either.

OBJECTIVE

This study aims to identify the indices which predict the efficacy of apremilast in psoriasis, and to investigate the impact of metabolic activity in immune cells on the psoriatic pathogenesis.

METHODS

The association of treatment efficacy with clinical and laboratory data of the 58 psoriatic patients was evaluated. The reflector of the associated index was also sought among the indices of cellular metabolic pathways by use of an extracellular flux analyzer.

RESULTS

There was a correlation between clinical improvement and the serum lactate dehydrogenase (LDH) level in the patients treated with apremilast but not in those with biologics. Serum LDH level did not correlate with the cutaneous disease severity but correlated with the oxygen consumption rate of blood T cells.

CONCLUSION

Psoriatic patients with high serum LDH level can be benefitted by apremilast. The serum LDH level reflects the augmented respiratory activity of T cells in psoriasis. Our results would highlight the importance of regarding metabolic skew in immune cells as a treatment target in psoriasis.

The CD8 T Cell-Epstein-Barr Virus-B Cell Trialogue: A Central Issue in Multiple Sclerosis Pathogenesis

The cause and the pathogenic mechanisms leading to multiple sclerosis (MS), a chronic inflammatory disease of the central nervous system (CNS), are still under scrutiny. During the last decade, awareness has increased that multiple genetic and environmental factors act in concert to modulate MS risk. Likewise, the landscape of cells of the adaptive immune system that are believed to play a role in MS immunopathogenesis has expanded by including not only CD4 T helper cells but also cytotoxic CD8 T cells and B cells. Once the key cellular players are identified, the main challenge is to define precisely how they act and interact to induce neuroinflammation and the neurodegenerative cascade in MS. CD8 T cells have been implicated in MS pathogenesis since the 80's when it was shown that CD8 T cells predominate in MS brain lesions. Interest in the role of CD8 T cells in MS was revived in 2000 and the years thereafter by studies showing that CNS-recruited CD8 T cells are clonally expanded and have a memory effector phenotype indicating in situ antigen-driven reactivation. The association of certain MHC class I alleles with MS genetic risk implicates CD8 T cells in disease pathogenesis. Moreover, experimental studies have highlighted the detrimental effects of CD8 T cell activation on neural cells. While the antigens responsible for T cell recruitment and activation in the CNS remain elusive, the high efficacy of B-cell depleting drugs in MS and a growing number of studies implicate B cells and Epstein-Barr virus (EBV), a B-lymphotropic herpesvirus that is strongly associated with MS, in the activation of pathogenic T cells. This article reviews the results of human studies that have contributed to elucidate the role of CD8 T cells in MS immunopathogenesis, and discusses them in light of current understanding of autoreactivity, B-cell and EBV involvement in MS, and mechanism of action of different MS treatments. Based on the available evidences, an immunopathological model of MS is proposed that entails a persistent EBV infection of CNS-infiltrating B cells as the target of a dysregulated cytotoxic CD8 T cell response causing CNS tissue damage.

Reversing Post-Infectious Epigenetic-Mediated Immune Suppression

The immune response must balance the pro-inflammatory, cell-mediated cytotoxicity with the anti-inflammatory and wound repair response. Epigenetic mechanisms mediate this balance and limit host immunity from inducing exuberant collateral damage to host tissue after severe and chronic infections. However, following treatment for these infections, including sepsis, pneumonia, hepatitis B, hepatitis C, HIV, tuberculosis (TB) or schistosomiasis, detrimental epigenetic scars persist, and result in long-lasting immune suppression. This is hypothesized to be one of the contributing mechanisms explaining why survivors of infection have increased all-cause mortality and increased rates of unrelated secondary infections. The mechanisms that induce epigenetic-mediated immune suppression have been demonstrated in-vitro and in animal models. Modulation of the AMP-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR), nuclear factor of activated T cells (NFAT) or nuclear receptor (NR4A) pathways is able to block or reverse the development of detrimental epigenetic scars. Similarly, drugs that directly modify epigenetic enzymes, such as those that inhibit histone deacetylases (HDAC) inhibitors, DNA hypomethylating agents or modifiers of the Nucleosome Remodeling and DNA methylation (NuRD) complex or Polycomb Repressive Complex (PRC) have demonstrated capacity to restore host immunity in the setting of cancer-, LCMV- or murine sepsis-induced epigenetic-mediated immune suppression. A third clinically feasible strategy for reversing detrimental epigenetic scars includes bioengineering approaches to either directly reverse the detrimental epigenetic marks or to modify the epigenetic enzymes or transcription factors that induce detrimental epigenetic scars. Each of these approaches, alone or in combination, have ablated or reversed detrimental epigenetic marks in in-vitro or in animal models; translational studies are now required to evaluate clinical applicability.

Current and emerging disease-modulatory therapies and treatment targets for multiple sclerosis

The treatment of multiple sclerosis (MS), the most common chronic inflammatory, demyelinating and neurodegenerative disease of the central nervous system (CNS), continues to transform. In recent years, a number of novel and increasingly effective disease-modulatory therapies (DMTs) have been approved, including oral fumarates and selective sphingosine 1-phosphate modulators, as well as cell-depleting therapies such as cladribine, anti-CD20 and anti-CD52 monoclonals. Amongst DMTs in clinical development, inhibitors of Bruton's tyrosine kinase represent an entirely new emerging drug class in MS, with three different drugs entering phase III trials. However, important remaining fields of improvement comprise tracking of long-term benefit-risk with existing DMTs and exploration of novel treatment targets relating to brain inherent disease processes underlying the progressive neurodegenerative aspect of MS, which accumulating evidence suggests start already early in the disease process. The aim here is to review current therapeutic options in relation to an improved understanding of the immunopathogenesis of MS, also highlighting examples where controlled trials have not generated the desired results. An additional aim is to review emerging therapies undergoing clinical development, including agents that interfere with disease processes believed to be important for neurodegeneration or aiming to enhance reparative responses. Notably, early trials now have shown initial evidence of enhanced remyelination both with small molecule compounds and biologicals. Finally, accumulating evidence from clinical trials and post-marketing real-world patient populations, which underscore the importance of early high effective therapy whilst maintaining acceptable tolerability, is discussed.

Glucose-impaired Corneal Re-epithelialization Is Promoted by a Novel Derivate of Dimethyl Fumarate

Glucose induces corneal epithelial dysfunctions characterized by delayed wound repair. Nuclear erythroid 2-related factor 2 (Nrf2) mediates cell protection mechanisms even through the Heme oxygenase-1 (HO-1) up-regulation. Here, we synthesized new HO-1 inducers by modifying dimethyl fumarate (DMF) and used docking studies to select VP13/126 as a promising compound with the best binding energy to Kelch-like ECH-associated protein 1 (keap1), which is the the regulator of Nrf2 nuclear translocation. We verified if VP13/126 protects SIRC cells from hyperglycemia compared to DMF. SIRC were cultured in normal (5 mM) or high glucose (25 mM, HG) in presence of DMF (1–25 μM) or VP13/126 (0.1–5 μM) with or without ERK1/2 inhibitor PD98059 (15 μM). VP13/126 was more effective than DMF in the prevention of HG-induced reduction of cell viability and proliferation. Reduction of wound closure induced by HG was similarly counteracted by 1 μM VP13/126 and 10 μM DMF. VP13/126 strongly increased phospho/total ERK1/2 and restored HO-1 protein in HG-treated SIRC; these effects are completely counteracted by PD98059. Moreover, high-content screening analysis showed a higher rate of Nrf2 nuclear translocation induced by VP13/126 than DMF in HG-stimulated SIRC. These data indicate that VP13/126 exerts remarkable pro-survival properties in HG-stimulated SIRC, promoting the Nrf2/HO-1 axis.

Encephalitogenic and Regulatory CD8 T Cells in Multiple Sclerosis and Its Animal Models

Multiple sclerosis (MS), a neuroinflammatory disease that affects millions worldwide, is widely thought to be autoimmune in etiology. Historically, research into MS pathogenesis has focused on autoreactive CD4 T cells because of their critical role in the animal model, experimental autoimmune encephalomyelitis, and the association between MS susceptibility and single-nucleotide polymorphisms in the MHC class II region. However, recent studies have revealed prominent clonal expansions of CD8 T cells within the CNS during MS. In this paper, we review the literature on CD8 T cells in MS, with an emphasis on their potential effector and regulatory properties. We discuss the impact of disease modifying therapies, currently prescribed to reduce MS relapse rates, on CD8 T cell frequency and function. A deeper understanding of the role of CD8 T cells in MS may lead to the development of more effective and selective immunomodulatory drugs for particular subsets of patients.

Antioxidant Therapy in Pancreatitis

Pancreatitis is pathologic inflammation of the pancreas characterized by acinar cell destruction and oxidative stress. Repeated pancreatic insults can result in the development of chronic pancreatitis, characterized by irreversible fibrosis of the pancreas and many secondary sequelae, ultimately leading to the loss of this important organ. We review acute pancreatitis, chronic pancreatitis, and pancreatitis-related complications. We take a close look at the pathophysiology with a focus on oxidative stress and how it contributes to the complications of the disease. We also take a deep dive into the evolution and current status of advanced therapies for management including dietary modification, antioxidant supplementation, and nuclear factor erythroid-2-related factor 2-Kelch-like ECH-associated protein 1(Nrf2-keap1) pathway activation. In addition, we discuss the surgeries aimed at managing pain and preventing further endocrine dysfunction, such as total pancreatectomy with islet auto-transplantation.

Inflammation in multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) that is characterised pathologically by demyelination, gliosis, neuro-axonal damage and inflammation. Despite intense research, the underlying pathomechanisms driving inflammatory demyelination in MS still remain incompletely understood. It is thought to be caused by an autoimmune response towards CNS self-antigens in genetically susceptible individuals, assuming autoreactive T cells as disease-initiating immune cells. Yet, B cells were recognized as crucial immune cells in disease pathology, including antibody-dependent and independent effects. Moreover, myeloid cells are important contributors to MS pathology, and it is becoming increasingly evident that different cell types act in concert during MS immunopathology. This is supported by the finding that the beneficial effects of actual existing disease-modifying therapies cannot be attributed to one single immune cell-type, but rather involve immunological cooperation. The current strategy of MS therapies thus aims to shift the immune cell repertoire from a pro-inflammatory towards an anti-inflammatory phenotype, involving regulatory T and B cells and anti-inflammatory macrophages. Although no existing therapy actually exists that directly induces an enhanced regulatory immune cell pool, numerous studies identified potential net effects on these cell types. This review gives a conceptual overview on T cells, B cells and myeloid cells in the immunopathology of relapsing-remitting MS and discusses potential contributions of actual disease-modifying therapies on these immune cell phenotypes.