IL-2 Treatment Research Articles

Epithelial dysfunction is prevented by IL-22 treatment in a Citrobacter rodentium-induced colitis model that shares similarities with inflammatory bowel disease

Inflammatory bowel disease (IBD) is characterized by a dysregulated intestinal epithelial barrier leading to breach of barrier immunity. Here we identified similar protein expression changes between IBD and Citrobacter rodentium-infected FVB mice with respect to dysregulation of solute transporters as well as components critical for intestinal barrier integrity. We attribute the disease associated changes in the model to the emergence of undifferentiated intermediate intestinal epithelial cells. Prophylactic treatment with IL-22.Fc in C. rodentium-infected FVB mice reduced disease severity and rescued the mice from lethality. Multi-omics and solute analyses revealed that IL-22.Fc treatment prevented disease-associated changes including disruption of the solute transporter machinery and restored proper physiological functions of the intestine, respectively. Taken together, we established the disease relevance of the C. rodentium-induced colitis model to IBD, demonstrated the protective role of IL-22 in amelioration of epithelial dysfunction and elucidated the molecular mechanisms with IL-22's effect on intestinal epithelial cells.

IL-33 Induces an Antiviral Signature in Mast Cells but Enhances Their Permissiveness for Human Rhinovirus Infection.

Mast cells (MCs) are classically associated with allergic asthma but their role in antiviral immunity is unclear. Human rhinoviruses (HRVs) are a major cause of asthma exacerbations and can infect and replicate within MCs. The primary site of HRV infection is the airway epithelium and MCs localise to this site with increasing asthma severity. The asthma susceptibility gene, IL-33, encodes an epithelial-derived cytokine released following HRV infection but its impact on MC antiviral responses has yet to be determined. In this study we investigated the global response of LAD2 MCs to IL-33 stimulation using RNA sequencing and identified genes involved in antiviral immunity. In spite of this, IL-33 treatment increased permissiveness of MCs to HRV16 infection which, from the RNA-Seq data, we attributed to upregulation of ICAM1. Flow cytometric analysis confirmed an IL-33-dependent increase in ICAM1 surface expression as well as LDLR, the receptors used by major and minor group HRVs for cellular entry. Neutralisation of ICAM1 reduced the IL-33-dependent enhancement in HRV16 replication and release in both LAD2 MCs and cord blood derived MCs. These findings demonstrate that although IL-33 induces an antiviral signature in MCs, it also upregulates the receptors for HRV entry to enhance infection. This highlights the potential for a gene-environment interaction involving IL33 and HRV in MCs to contribute to virus-induced asthma exacerbations.

IL7RA single nucleotide polymorphisms are associated with the size and function of the MAIT cell population in treated HIV-1 infection.

MAIT cells are persistently depleted and functionally exhausted in HIV-1-infected patients despite long-term combination antiretroviral therapy (cART). IL-7 treatment supports MAIT cell reconstitution in vivo HIV-1-infected individuals and rescues their functionality in vitro. Single-nucleotide polymorphisms (SNPs) of the IL-7RA gene modulate the levels of soluble(s)IL-7Rα (sCD127) levels and influence bioavailability of circulating IL-7. Here we evaluate the potential influence of IL-7RA polymorphisms on MAIT cell numbers and function in healthy control (HC) subjects and HIV-1-infected individuals on long-term cART. Our findings indicate that IL-7RA haplotype2 (H2*T), defined as T-allele carriers at the tagging SNP rs6897932, affects the size of the peripheral blood MAIT cell pool, as well as their production of cytokines and cytolytic effector proteins in response to bacterial stimulation. H2*T carriers had lower sIL-7Rα levels and higher MAIT cell frequency with enhanced functionality linked to higher expression of MAIT cell-associated transcription factors. Despite an average of 7 years on suppressive cART, MAIT cell levels and function in HIV-1-infected individuals were still significantly lower than those of HC. Notably, we observed a significant correlation between MAIT cell levels and cART duration only in HIV-1-infected individuals carrying IL-7RA haplotype 2. Interestingly, treatment with sIL-7Rα in vitro suppressed IL-7-dependent MAIT cell proliferation and function following cognate stimulations. These observations suggest that sIL-7Rα levels may influence MAIT cell numbers and function in vivo by limiting IL-7 bioavailability to MAIT cells. Collectively, these observations suggest that IL-7RA polymorphisms may play a significant role in MAIT cell biology and influence MAIT cells recovery in HIV-1 infection. The potential links between IL7RA polymorphisms, MAIT cell immunobiology, and HIV-1 infection warrant further studies going forward.

MSN@IL-4 Sustainingly Mediates Macrophagocyte M2 Polarization and Relieves Osteoblast Damage via NF-κB Pathway-Associated Apoptosis.

Background The microenvironment of bone defects displayed that M2 polarization of macrophagocyte could promote the osteoblast growth and benefit the wound healing. Bone scaffold transplantation is considered to be one of the most promising methods for repairing bone defects. The present research was aimed at constructing a kind of novel bone scaffold nanomaterial of MSN@IL-4 for treating bone defects responding to the wound microenvironment of bone defects and elucidating the mechanics of MSN@IL-4 treating bone defect via controlling release of IL-4, inducing M2 polarization and active factor release of macrophagocyte, and eventually relieving osteoblast injury. Methods MSN@IL-4 was firstly fabricated and its release of IL-4 was assessed in vitro. Following, the effects of MSN@IL-4 nanocomplex on the release of active factors of macrophage were examined using Elisa assay and promoting M2 polarization of the macrophage by immunofluorescence staining. And then, the effects of active factors from macrophage supernatant induced by MSN@IL-4 on osteoblast growth were examined by CCK-8, flow cytometry, and western blot assay. Results The release curve of IL-4 in vitro displayed that there was more than 80% release ratio for 30th day with a sustained manner in pH 5.5. Elisa assay data showed that MSN@IL-4 nanocomplex could constantly promote the release of proproliferative cytokine IL-10, SDF-1α, and BMP-2 in macrophagocyte compared to only IL-4 treatment, and immunofluorescent image showed that MSN@IL-4 could promote M2 polarization of macrophagocytes via inducing CD206 expression and suppressing CD86 expression. Osteoblast injury data showed that the supernatant from macrophagocyte treated by MSN@IL-4 could promote the osteoblast proliferation by MTT assay. Flow cytometry data showed that the supernatant from macrophagocyte treated by MSN@IL-4 could suppress the osteoblast apoptosis from 22.1% to 14.6%, and apoptosis-related protein expression data showed that the supernatant from macrophagocyte treated by MSN@IL-4 could suppress the expression of Bax, cleaved caspase 3, and cleaved caspase 8. Furthermore, the immunofluorescent image showed that the supernatant from macrophagocyte treated by MSN@IL-4 could inhibit nucleus location of p65, and western blot data showed that the supernatant from macrophagocyte treated by MSN@IL-4 could suppress the phosphorylation of IKK and induce the expression of IκB. Conclusion MSN@IL-4 could control the sustaining release of IL-4, and it exerts the protective effect on osteoblast injury via inducing M2 polarization and proproliferative cytokine of macrophagocyte and following inhibiting the apoptosis and NF-κB pathway-associated inflammation of osteoblast.

Engineered human cytokine/antibody fusion proteins expand regulatory Tcells and confer autoimmune disease protection.

Low-dose human interleukin-2 (hIL-2) treatment is used clinically to treat autoimmune disorders due to the cytokine's preferential expansion of immunosuppressive regulatory Tcells (Tregs). However, off-target immune cell activation and short serum half-life limit the clinical potential of IL-2 treatment. Recent work showed that complexes comprising hIL-2 and the anti-hIL-2 antibody F5111 overcome these limitations by preferentially stimulating Tregs over immune effector cells. Although promising, therapeutic translation of this approach is complicated by the need to optimize dosing ratios and by the instability of the cytokine/antibody complex. We leverage structural insights to engineer a single-chain hIL-2/F5111 antibody fusion protein, termed F5111 immunocytokine (IC), which potently and selectively activates and expands Tregs. F5111 IC confers protection in mouse models of colitis and checkpoint inhibitor-induced diabetes mellitus. These results provide a roadmap for IC design and establish a Treg-biased immunotherapy that could be clinically translated for autoimmune disease treatment.

Experimental and Clinical Evidence Suggests That Treatment with Betacellulin Can Alleviate Th2-Type Cytokine-Mediated Impairment of Skin Barrier Function.

Betacellulin (BTC) is a peptide ligand that belongs to the epidermal growth factor family, the members of which have been implicated in skin morphogenesis, homeostasis, repair, and angiogenesis; however, the role of BTC in the regulation of the skin barrier remains unknown. To examine the role of BTC in skin barrier function, we analyzed atopic dermatitis (AD) transcriptomic data from Gene Expression Omnibus (GEO) datasets, performed BTC immunohistochemistry using human skin tissues, and evaluated the effects of BTC on primary human keratinocytes by real-time PCR, Western blotting, and assay of the transepidermal electrical resistance (TER), a functional parameter to monitor the tight junction barrier. We found that the gene expression of BTC was downregulated in skin lesions from patients with AD, and this downregulated expression recovered following biological treatments. Consistently, the BTC protein levels were downregulated in the lesional skin of AD patients compared with the normal skin of healthy participants, suggesting that the BTC levels in skin might be a biomarker for the diagnosis and therapy of AD. Furthermore, in human keratinocytes, BTC knockdown reduced the levels of skin-derived antimicrobial peptides and skin barrier-related genes, whereas BTC addition enhanced their levels. Importantly, in human skin equivalents, BTC restored the increased tight junction permeability induced by Th2 cytokine IL-4/IL-13 treatment. In addition, specific inhibitors of epidermal growth factor receptor (EGFR) and protein kinase C (PKC) abolished the BTC-mediated improvement in skin barrier-related proteins in keratinocyte monolayers. Collectively, our findings suggest that treatment with BTC might improve the Th2-type cytokine-mediated impairment of skin barrier function through the EGFR/PKC axis and that BTC might be a novel potential biomarker and therapeutic target for the treatment of skin conditions characterized by the overproduction of Th2 cytokines and dysfunctional skin barriers, such as AD.

IL-3 regulates the differentiation of pathogenic Th17 cells.

IL-17-producing Th17 cells play an important role in pathogenesis of rheumatoid arthritis (RA). Aberrant immune activation due to an imbalance between Th17 and regulatory T (Treg) cells is associated with the development of RA and other autoimmune diseases. Targeting pathogenic Th17 cells and their associated molecules is emerging as a promising strategy to treat and reverse RA. Here, we demonstrate that IL-3 inhibits the differentiation of Th17 cells and promotes the development of Treg cells in IL-2-dependent manner. In IL-2 KO mice, we observed that IL-3 has no effect on differentiation of both Th17 and Treg cells. In addition, IL-3 decreases pathogenic IL-17A+ TNF-α+ , IL-17A+ IFN-γ+ and IL-23R+ Th17 cells, secretion of GM-CSF and IFN-γ, and osteoclastogenesis when presented in the culture together with Th17 polarizing cytokines. Mechanistically, IL-3 regulates the development of Th17 cells through the inhibition of STAT3 phosphorylation. IL-3 treatment significantly decreases the pathogenic Th17 cell responses and arthritic scores in the mouse model of RA. Importantly, IL-3 inhibits the differentiation of human Th17 cells. Thus, our results suggest a novel therapeutic role of IL-3 in the regulation of Th17 cell-mediated pathophysiology of RA.

Beneficial effects of antitranspirants on water stress tolerance in maize under different plant densities in newly reclaimed land

BackgroundThe global freshwater shortage is an important issue threatening the sustainable development of agriculture and food security. A field study was conducted in two seasons, i.e., 2019 and 2020, in the newly reclaimed land at Village 8, El-Minia Governorate, Egypt, to evaluate maize crop response to three irrigation levels (IL1 = 80, IL2 = 70, and IL3 = 60% of the crop evapotranspiration “ETc”), three plant densities (PD1 = 17.500, PD2 = 23.333, and PD3 = 35.000 plants fed−1), and three antitranspirants treatments (An1 = control, An2 = kaolin at 6%, and An3 = chitosan at 150 L fed−1). The experiment was designed as a randomized complete block design (RCBD) using a split plot in strips.ResultsResults revealed that the irrigated maize plants with IL1 (80% of ETc) recorded the maximum values for all traits such as vegetative growth, phenology, and yield and its attributes in both seasons. The heaviest value of grain yield (3.15 and 3.10 tonnes fed−1, where 1 feddan = 0.42 hectare) was realized from IL1 treatment in the 1st and 2nd seasons, respectively. Plant density of 35.000 plants fed−1 (PD3) produced the greatest values of leaf area index (6.70 and 6.85), more days to 50% for each of tasseling (62.16 and 61.99 days), and silking (63.63 and 63.73 days), heaviest grain yield (3.11 and 3.16 ton fed−1) and greater water use efficiency WUE (1.46 and 1.48 kg m−3) in both seasons, respectively.ConclusionsFoliar spraying with antitranspirants, i.e., kaolin at 6%, led to a tremendous impact on all studied traits by alleviating the water stress and reducing the rate of transpiration. The effect of second-order interaction among IL1 × PD3 × An3 indicated a significant increase in grain yield by 69.91% as compared with the interaction of IL3 × PD1 × An1 in the 2020 season only. CS 10 single-cross maize realized the highest productivity and most efficient use of available resources via using a sowing density of 35.000 plant fed−1, foliar spraying with kaolin at 6%, and irrigation level (80% of ETc) under El-Minia conditions.

The Effect of Ginseng Extract on Serum Interleukin-6 Levels in Patients with Community-Acquired Pneumonia

Community-Acquired Pneumonia (CAP) is the most common cause of death and illness in the world. Increased IL-6 can be used as an early indicator of infection or inflammation. Ginseng is a popular herbal medicine. The anti-inflammatory effect of Ginseng is mediated by its ability to inhibit Nuclear Factor Kappa Beta (NF-kB), a proinflammatory regulator to initiate the synthesis of cytokines TNF-α, IL-1β, IL-6, and IL-8. Clinical trial research, quasi-experimental design with a pretest-posttest approach was carried out on 26 community pneumonia patients who were hospitalized at Dr. Moewardi Hospital, Surakarta from October 2020 to January 2021 using purposive sampling. The independent variable was Ginseng extract (GinsanaR) at a dose of 2x100 mg and the dependent variable was serum IL-6 levels. Serum IL-6 levels were measured using the Sandwich Enzyme-Linked Immunoabsorbent Assay (ELISA) method. Mean IL-6 levels in the control group on day 0, day 3, and day 14 were 232,89+156,61 pg/mL, 113,46±83.30 pg/mL and 66.18±66.02 pg/mL, respectively (p=<0.001). Mean IL-6 levels in the treatment group on day 0, day 3, and day 14 were 519,55±609,19 pg/mL, 205.41±329.17 pg/mL and 133,59±291,68 pg/mL, respectively (p=<0.001). Delta IL-6 levels in the control group and the treatment group on day 3 compared to day 0, the mean of the IL-6 control group -119,42±111,70 pg/mL, the mean for the IL-6 treatment group -314,14±532,16 pg/mL; On day 14 compared to day 0, the mean of the IL-6 control group was -166,70±135,54 pg/mL, the mean of the IL-6 treatment group was -385,96±547,10 pg/mL; On day 14 compared to day 3, the mean IL-6 control group was -47.28±47.47, the mean IL-6 control group was -71.82±58.16. The post hoc test (Wilcoxon) obtained a p-value < 0.05, suggesting that Ginseng extract has a significant effect on reducing serum IL-6 serum levels in community pneumonia patients.

Human differentiated eosinophils release IL-13 in response to IL-33 stimulation.

ObjectiveEosinophils are hallmarks in allergic type 2 inflammation and are known to release cytotoxic granule proteins that contribute to inflammation. Eosinophils develop in the bone marrow from hematopoietic stem cells and once mature, have a limited lifespan in culture, making them difficult to study ex vivo. IL-33 has increasingly been shown as a key regulator of type 2 inflammation via signaling through its receptor, ST2. The present study was conducted to detail a method of eosinophil differentiation from hematopoietic stem cells and determine the response to IL-33.MethodsCD34+ and CD14+ cells were isolated from donor apheresis cones and differentiated into eosinophils or macrophage controls, respectively. Morphologic, transcriptional and protein analyses were performed to validate this method of eosinophil differentiation. The effect of IL-33 on differentiated eosinophils was assessed using qPCR, immunofluorescence, and multiplex cytokine array.ResultsCD34 differentiated eosinophils appear morphologically similar by H&E and express eosinophil peroxidase (EPX) protein as well as the conventional eosinophil transcripts EPX, CLC, and MBP. In addition, differentiated eosinophils expressed both isoforms of the IL-33 receptor, ST2L and sST2 throughout the differentiation process. Transcript levels of both IL-33 receptors were up-regulated by treatment with IL-33 at earlier timepoints in the differentiation. These cells also expressed IL-4 and IL-13 mRNA which were up-regulated by IL-33 as well. Notably, IL-13 expression was significantly higher with IL-33 treatment compared to media control at every timepoint measured. IL-33 significantly increased cellular secretion of IL-13 protein at most timepoints throughout differentiation. IL-8, LIF, CCL1, CCL5, CCL7, and CCL8 were also significantly secreted after IL-33 stimulation.ConclusionsOur findings suggest that CD34 differentiated eosinophils are morphologically and phenotypically similar to peripheral eosinophils. The release of specific cytokines in direct response to IL-33 may contribute to the pathogenesis of type 2 inflammation and facilitates new avenues for studying eosinophils as effector cells in vitro.

Distinct Predictive Immunogenomic Profiles of Response to Immune Checkpoint Inhibitors and IL2: A Real-world Evidence Study of Patients with Advanced Renal Cancer.

Next-generation IL2 agents, designed for improved tolerability over traditional HD-IL2 (aldesleukin), are in clinical development. Retrospective molecular tumor profiling of patients treated with HD-IL2 or anti-PD-1 therapy provides insights into genomic characteristics of therapy response. This study revealed common and distinct immune-related predictive response markers for IL2 and anti-PD-1 therapy which may play a role in therapy guidance, and rational combination strategies for these agents.

Combined Regulatory T-Lymphocyte and IL-2 Treatment Is Safe, Tolerable, and Biologically Active for 1 Year in Persons With Amyotrophic Lateral Sclerosis.

Background and ObjectivesIn a phase 1 amyotrophic lateral sclerosis (ALS) study, autologous infusions of expanded regulatory T-lymphocytes (Tregs) combined with subcutaneous interleukin (IL)-2 were safe and well tolerated. Treg suppressive function increased and disease progression stabilized during the study. The present study was conducted to confirm the reliability of these results.MethodsParticipants with ALS underwent leukapheresis, and their Tregs were isolated and expanded in a current Good Manufacturing Practice facility. Seven participants were randomly assigned in a 1:1 ratio to receive Treg infusions (1 × 106 cells/kg) IV every 4 weeks and IL-2 (2 × 105 IU/m2) injections 3 times/wk or matching placebo in a 24-week randomized controlled trial (RCT). Six participants proceeded into a 24-week dose-escalation open-label extension (OLE). Two additional participants entered directly into the OLE. The OLE included dose escalation of Treg infusions to 2 × 106 cells/kg and 3 × 106 cells/kg at 4-week intervals.ResultsThe Treg/IL-2 treatments were safe and well tolerated, and Treg suppressive function was higher in the active group of the RCT. A meaningful evaluation of progression rates in the RCT between the placebo and active groups was not possible due to the limited number of enrolled participants aggravated by the COVID-19 pandemic. In the 24-week OLE, the Treg/IL-2 treatments were also safe and well tolerated in 8 participants who completed the escalating doses. Treg suppressive function and numbers were increased compared with baseline. Six of 8 participants changed by an average of −2.7 points per the ALS Functional Rating Scale–Revised, whereas the other 2 changed by an average of −10.5 points. Elevated levels of 2 markers of peripheral inflammation (IL-17C and IL-17F) and 2 markers of oxidative stress (oxidized low-density lipoprotein receptor 1 and oxidized LDL) were present in the 2 rapidly progressing participants but not in the slower progressing group.DiscussionTreg/IL-2 treatments were safe and well tolerated in the RCT and OLE with higher Treg suppressive function. During the OLE, 6 of 8 participants showed slow to no progression. The 2 of 8 rapid progressors had elevated markers of oxidative stress and inflammation, which may help delineate responsiveness to therapy. Whether Treg/IL-2 treatments can slow disease progression requires a larger clinical study (ClinicalTrials.gov number, NCT04055623).Classification of EvidenceThis study provides Class IV evidence that Treg infusions and IL-2 injections are safe and effective for patients with ALS.

Abstract P3060: Circulating Gut Microbial Peptides Exacerbate Cardiac Dysfunction In IL10KO Mice Following Transaortic Constriction

Background: Heart failure is the leading cause of morbidity and mortality in the USA. Recently, impaired intestinal permeability is known to augment cardiac dysfunction. Though, the cardioprotective role of IL10 is well known, its role in reducing gut dysbiosis and maintaining intestinal permeability during hypertrophic heart failure is not known. We hypothesized that IL10 maintains intestinal permeability and inhibits the release of gut microbial peptides (GMPs) which ultimately improves cardiac function. Methods: WT & IL10KO mice were subjected to TAC or sham surgery. Heart and intestine were collected to evaluate inflammation genes expression, immune cell infiltration (flow cytometry), and intestinal permeability (WB and immunohistochemistry). Blood was collected to quantify peptidoglycan (PGN) and other bacterial metabolites (TMAO) levels. The effect of PGN on mitochondrial functions was evaluated in neonatal cardiomyocytes. Results: Cardiac functions were significantly reduced in IL10KO mice following TAC. IL10 KO mice showed exacerbated inflammation (IL1β, IL6 and TNFα genes expression) following TAC. TAC induced leukocytes (monocyte/macrophage, T-cell and neutrophils) recruitments in the intestine in IL10KO mice. TAC mice showed gut dysbiosis (16S rRNA sequencing) in IL10KO mice. Further, IL10KO mice exhibited higher intestinal permeability as shown by increase in PV1 level and reduction in zonulin-1 (ZO-1) protein. Plasma PGN level was significantly increased in IL10KO mice following TAC. Pathway-based cardiotoxicity array showed a significant increase in uncoupler protein 2 (UCP2) and phospholamban (PLN; a calcium handling protein) genes expression in cardiomyocytes following PGN treatment. Finally, IL10 treatment restores PGN-induced decrease in mitochondrial membrane potential (TMRE assay) in cardiomyocytes. Conclusion: Taken together, data suggest that IL-10 helps to maintain gut wall permeability and reduced gut microbial peptide circulation to the heart and thus improves cardiac function by improving mitochondrial function. Ongoing investigations using molecular approaches will provide a better understanding of gut-heart signaling and its impact on the progress of heart failure.

IL-25 ameliorates acute cholestatic liver injury via promoting hepatic bile acid secretion

Cholestasis caused by bile secretion and excretion disorders is a serious manifestation of hepatopathy. Interleukin (IL)-25 is a member of the IL-17 cytokine family, which involves in mucosal immunity and type 2 immunity via its receptor—IL-17RB. Our previous studies have shown that IL-25 improves non-alcoholic fatty liver via stimulating M2 macrophage polarization and promotes development of hepatocellular carcinoma via alternative activation of macrophages. These hepatopathy are closely associated with cholestasis. However, whether IL-25 play an important role in cholestasis remains unclear. IL-25 treatment and IL-25 knockout (Il25-/-) mice were injected intragastrically with α-naphthyl isothiocyanate (ANIT) to determine the biological association between IL-25 and cholestasis. Here, we found that IL-25 and IL-17RB decreased in ANIT-induced cholestatic mice. Il25-/- mice showed exacerbated ANIT-induced parenchymal injury and IL-25 treatment significantly alleviated cholestatic liver injury induced by ANIT. We found that IL-25 reduced the level of hepatic total bile acids and increased the expression of multidrug resistance-associated protein 2 (MRP2) and multidrug resistance-associated protein 3 (MRP3) in liver. In conclusion, IL-25 exhibited a protective effect against ANIT-induced cholestatic liver injury in mice, which may be related to the regulation on bile acids secretion. These results provide a theoretical basis for the use of IL-25 in the treatment of cholestatic hepatopathy.

Magnesium isoglycyrrhizinate ameliorates lipopolysaccharide-induced liver injury by upregulating autophagy and inhibiting inflammation via IL-22 expression

Liver disease has become a major cause of premature mortality worldwide. It is well known that dysregulated inflammation response plays a crucial role in most liver diseases. As a Chinese medicinal herb, Magnesium isoglycyrrhizinate (MgIG) has been proven to have good hepatoprotective activity and has been used in clinic to treat liver disease. However, the mechanisms by which MgIG regulates LPS-induced liver injury and inflammation in vivo remain elusive. In our study, MgIG pretreatment mitigated LPS-induced liver damage by suppressing apoptosis and inflammation via regulating macrophage/neutrophil infiltration. MgIG ameliorated the effects of LPS on pro-oxidant enzymes (NOX1/2/4) and anti-oxidant enzymes (SOD1/2). Interestingly, we found that the level of the hepatoprotective cytokine interleukin (IL)–22 was significantly upregulated in MgIG-treated liver tissues, which might be a potential mechanism of MgIG against liver injury. Moreover, we found that MgIG treatment not only inhibited TLR4/MyD88/NF-κB signaling pathway, but also activated autophagy. Furthermore, IL-22 treatment activated autophagy and inhibited TLR4/NF-κB signaling pathway in vitro, suggesting that IL-22-activated autophagy and -inhibited inflammation also participated in the protective effects of MgIG. Altogether, our results uncovered the potential mechanisms of the hepatoprotective effects of MgIG, which provided critical evidence to support the use of MgIG to prevent and treat liver diseases.

Three Days Delayed Recanalization Improved Neurological Function in pMCAO Rats by Increasing M2 Microglia-Possible Involvement of the IL-4R/STAT6/PPARγ Pathway.

Current approved therapies for acute ischemic stroke have a restricted therapeutic time window. Delayed recanalization, which has been utilized clinically in patients who have missed the time window for administration, may be a promising alternative for stroke patients. However, the underlying molecular mechanisms remain undiscovered. Herein, we hypothesized that delayed recanalization would increase M2 microglial polarization through the IL-4R (interleukin-4 receptor)/STAT6 (signal transducer and activators of transcription 6)/PPARγ (peroxisome proliferator-activated receptor γ) pathway, subsequently promoting stroke recovery in rats. The permanent middle cerebral artery occlusion (pMCAO) model was induced via intravascular filament insertion. Recanalization was induced by withdrawing the filament at 3days after MCAO (rMCAO). Interleukin (IL)-4 was administered intranasally at 3days after pMCAO. AS1517499, a specific STAT6 inhibitor, was administered intranasally at 3days after MCAO induction. Immunofluorescence staining, enzyme-linked immunosorbent assay (ELISA), western blot analysis, volumetric measurements of brain infarct, and neurological behavior tests were conducted. Delayed recanalization at 3days after MCAO increased the polarization of M2 microglia, decreased inflammation, and improved neurological behavior. IL-4 treatment administered on the 3rd day after pMCAO increased M2 microglial polarization, improved neurological behavior, and reduced infarction volume of pMCAO rats. The inhibition of STAT6 decreased the level of p-STAT6 and PPARγ in rats treated with delayed recanalization. Delayed recanalization improved neurological function by increasing microglial M2 polarization, possibly involved with the IL-4R/STAT6/PPARγ pathway after MCAO in rats.

IL-33/ST2 Activation Is involved in Ro60-Regulated Photosensitivity in Cutaneous Lupus Erythematosus.

Interleukin- (IL-) 33 contributes to various inflammatory processes. IL-33/ST2 activation participates in systemic lupus erythematous via binding to the receptor of Suppression of Tumorigenicity 2 protein (ST2). However, whether IL-33/ST2 interferes with the nosogenesis of cutaneous lupus erythematosus (CLE) has not been reported so far. Herein, we proposed to disclose the impacts on IL-33/ST2 activation and Ro60 on CLE and their potential implications in the photosensitization of CLE cells. IL-33, ST2, and Ro60 in CLE patients' skin lesions were detected. Murine keratinocytes stimulated with or without IL-33 were irradiated by ultraviolet B (UVB), and the levels of Ro60 and inflammation markers were determined. Keratinocytes were cocultured with J774.2 macrophages and stimulated with IL-33 for analysis of chemostasis. The results identified that IL-33, ST2, and downstream inflammation markers were significantly upregulated in CLE lesions with Ro60 overexpression. Additionally, IL-33 treatment promoted the upregulation of Ro60 induced by UVB treatment in murine keratinocytes. Moreover, IL-33 stimulates keratinocytes to induce macrophage migration via enhancing the generation of the chemokine (C–C motif) ligands 17 and 22. Meanwhile, the silencing of ST2 or nuclear factor-kappa B (NF-κB) suppression abolished IL-33-induced upregulation of Ro60 in keratinocytes. Similarly, the inhibition of SOX17 expression was followed by downregulation of Ro60 in keratinocytes following IL-33 stimulation. In addition, UVB irradiation upregulated SOX17 in keratinocytes. Conclusively, the IL-33/ST2 axis interferes with Ro60-regulated photosensitization via activating the NF-κB- and PI3K/Akt- and SOX17-related pathways.

B-cell acute lymphoblastic leukemia promotes an immune suppressive microenvironment that can be overcome by IL-12

Immunotherapies have revolutionized the treatment of B-cell acute lymphoblastic leukemia (B-ALL), but the duration of responses is still sub-optimal. We sought to identify mechanisms of immune suppression in B-ALL and strategies to overcome them. Plasma collected from children with B-ALL with measurable residual disease after induction chemotherapy showed differential cytokine expression, particularly IL-7, while single-cell RNA-sequencing revealed the expression of genes associated with immune exhaustion in immune cell subsets. We also found that the supernatant of leukemia cells suppressed T-cell function ex vivo. Modeling B-ALL in mice, we observed an altered tumor immune microenvironment, including compromised activation of T-cells and dendritic cells (DC). However, recombinant IL-12 (rIL-12) treatment of mice with B-ALL restored the levels of several pro-inflammatory cytokines and chemokines in the bone marrow and increased the number of splenic and bone marrow resident T-cells and DCs. RNA-sequencing of T-cells isolated from vehicle and rIL-12 treated mice with B-ALL revealed that the leukemia-induced increase in genes associated with exhaustion, including Lag3, Tigit, and Il10, was abrogated with rIL-12 treatment. In addition, the cytolytic capacity of T-cells co-cultured with B-ALL cells was enhanced when IL-12 and blinatumomab treatments were combined. Overall, these results demonstrate that the leukemia immune suppressive microenvironment can be restored with rIL-12 treatment which has direct therapeutic implications.

Functional Restoration of Exhausted CD8 T Cells in Chronic HIV-1 Infection by Targeting Mitochondrial Dysfunction.

CD8 T cell exhaustion is a hallmark of HIV-1 infection, characterized by phenotypic and functional CD8 T cell abnormalities that persist despite years of effective antiretroviral treatment (ART). More recently, the importance of cellular metabolism in shaping T cell antiviral function has emerged as a crucial aspect of immunotherapeutics aimed at re-invigorating exhausted CD8 T cells but remains under-investigated in HIV-1 infection. To gain a better insight into this process and identify new targets for effective CD8 T cell restoration we examined the metabolic profile of exhausted CD8 T cells in HIV-1 infection. We show that relative to HIV-1 elite controllers (EC) and HIV-1 seronegative donors, CD8 T cells from HIV-1 viraemic individuals are skewed toward a PD-1hiEOMEShiT-betlowTIGIT+ phenotype that is maintained during ART. This exhausted signature is enriched in HIV-specific CD8 T cells, compared to CMV-specific CD8 T cell populations, and further delineated by higher expression of the glucose transporter, Glut-1, impaired mitochondrial function and biogenesis, reflecting underlying metabolic defects. A notable improvement in antiviral HIV-specific CD8 T cell function was elicited via mitochondrial antioxidant treatment in combination with pharmacological modulation of mitochondrial dynamics and IL-15 treatment. These findings identify mitochondria as promising targets for combined reconstitution therapies in HIV-1 infection.

IL-27 regulates autophagy in rheumatoid arthritis fibroblast-like synoviocytes via STAT3 signaling

Rheumatoid arthritis (RA) is a highly prevalent autoimmune condition associated with pronounced synovial inflammation. The majority of RA patients required long-term treatment to control disease progression, thus imposing a significant financial burden on affected individuals. The development of RA is critically influenced by fibroblast-like synoviocytes (FLSs) within the synovial lining. IL-27 is an IL-6/IL-12 family cytokine that has recently been shown to play varied pro-inflammatory or protective roles in particular autoimmune diseases. However, the effects of IL-27 on FLSs in the context of RA have yet to be clarified and warrant further research. This study was developed to evaluate the impact of IL-27 treatment on apoptotic and autophagic activity in RA-associated FLSs, with a particular focus on the role of the STAT3 pathway in this regulatory context. Through these experiments, we found that IL-27 was able to suppress FLS proliferation and autophagic activity, with a high dose of this cytokine (100 ng/mL) markedly suppressing autophagy while simultaneously inducing some level of cellular apoptosis. The STAT3 inhibitor STA21 was found to reverse the IL-27-mediated suppression of autophagic activity in these RA-associated FLSs. Imbalanced cellular proliferation and apoptosis is of critical importance in the context of RA progression, and we found that IL-27 was able to regulate such imbalance and to enhance the apoptotic activity of RA FLSs by inhibiting rapamycin-activated autophagy. Together, these results indicate that IL-27 can regulate autophagic activity within RA-associated FLSs via the STAT3 signaling pathway, leading to inhibition of cellular proliferation.