IL-10 Expression Research Articles

The PPAR-α selective agonist WY14643 improves lupus nephritis via the downregulation of the RORγT/STAT3 signaling pathway in MRL/lpr mice.

Systemic lupus erythematosus (SLE) is a classic autoimmune disorder that mostly affects young women and involves various organs, such as the skin, joints, central nervous system, and kidneys. WY14643, a selective agonist of peroxisome proliferator-activated receptor-α, has previously shown anti-inflammatory effects in various disease models. However, its effects on lupus nephritis are yet to be explored. Therefore, the efficacy of WY14643 on renal biomarkers and lupus nephritis was assessed in MRL/lpr mice. Flow cytometry was used to examinethe effects of WY14643 on the expression of IL-17A, STAT3, RORγT, IL-21, IL-21R, IL-22, and TNF-α in splenic CD4+ T cells. We further investigated the impact of WY14643 on the mRNA expression of IL-17A, STAT3, RORγT, IL-21, IL-21R, IL-22, and TNF-α in kidney tissue via RT-PCR analysis. The administration of WY14643 effectively improved the symptoms of lupus nephritis in MRL/lpr mice. The administration of WY14643 decreased serum albumin, urine protein, serum creatinine, and blood urea nitrogen levels in MRL/lpr mice. WY14643 reduced the levels of inflammatory markers, including CD4+IL-17A+, CD4+STAT3+, CD4+RORγT+, CD4+IL-21+, CD4+IL-21R+, CD4+IL-22+, and CD4+TNF-α+, in the spleen cells of MRL/lpr mice. Additionally, we discovered that the administration of WY14643 resulted in the suppression of mRNA levels of IL-17A, STAT3, RORγT, IL-21, IL-22, and TNF-α. The current work shows that the suppression of inflammatory cells by WY14643 may effectively reduce autoimmune characteristics, such as renal inflammation, in lupus-prone MRL/lpr mice. Therefore, WY14643, being a specific PPAR-α agonist, shows significant potential as a novel therapeutic option for treatingnephritis associated with SLE, offering hope for future treatments in this challenging field.

FcεRI/PLC axis promotes anandamide synthesis and the formation of CB2-GPR55 heteromers, modulating cytokine production in mast cells.

Mast cells (MC) are crucial effectors in immediate allergic reactions. Monomeric IgE sensitizes MC and triggers various signaling responses. FcεRI/IgE/antigen crosslinking induces the release of several mediators, including bioactive lipids, but little is known about endocannabinoids (eCBs) secretion. Here, we studied the effects of IgE-induced sensitization and FcεRI crosslinking on anandamide (AEA) synthesis and release in bone marrow-derived mast cells (BMMC). Our results showed that mIgE induced AEA secretion through phospholipase C activation. Secreted AEA contributed to p38 phosphorylation induced by mIgE sensitization. Prolonged mIgE sensitization promoted the formation of long-lasting CB2-GPR55 heteromers. FcεRI crosslinking also caused AEA production. Notably, CB2 deficiency increased IL-2 and IL-3 cytokine expression in response to FcɛRI crosslinking. CB2 and GPR55 agonists reduced IL-2 and IL-3 mRNA expression caused by FcεRI activation. Our findings suggest that a) IgE binding to FcɛRI and its antigen-dependent activation leads to an AEA-dependent autocrine regulatory loop that contributes to intracellular signaling in MC and that b) CB2 and GPR55 receptors play a critical role in modulating the effector phase of MC activation by specifically regulating cytokine expression.

Efficacy and Mechanism of Highly Active Umbilical Cord Mesenchymal Stem Cells in the Treatment of Osteoporosis in Rats.

A rat model of osteoporosis was induced with dexamethasone sodium phosphate. Highly active umbilical cord mesenchymal stem cells (HA-UCMSCs) and UCMSCs were isolated, cultured, identified, and infused intravenously once at a dose of 2.29 × 106 cells/kg. In the 4th week of treatment, bone mineral density (BMD) was evaluated via cross-micro-CT, tibial structure was observed via HE staining, osteogenic differentiation of bone marrow mesenchymal stem cells (BMMSCs) was examined via alizarin red staining, and carboxy-terminal cross-linked telopeptide (CTX), nuclear factor-κβ ligand (RANKL), procollagen type 1 N-terminal propeptide (PINP) and osteoprotegerin (OPG) levels were investigated via enzyme-linked immunosorbent assays (ELISAs). BMMSCs were treated with 10-6 mol/L dexamethasone and cocultured with HA-UCMSCs and UCMSCs in transwells. The osteogenic and adipogenic differentiation of BMMSCs was subsequently examined through directional induction culture. The protein expression levels of WNT, β-catenin, RUNX2, IFN-γ and IL-17 in the bone tissue were measured via Western blotting. The BMD in the healthy group was higher than that in the model group. Both UCMSCs and HA-UCMSCs exhibited a fusiform morphology; swirling growth; high expression of CD73, CD90 and CD105; and low expression of CD34 and CD45 and could differentiate into adipocytes, osteoblasts and chondrocytes, while HA-UCMSCs were smaller in size; had a higher nuclear percentage; and higher differentiation efficiency. Compared with those in the model group, the BMD increased, the bone structure improved, the trabecular area, number, and perimeter increased, the osteogenic differentiation of BMMSCs increased, RANKL expression decreased, and PINP expression increased after UCMSC and HA-UCMSC treatment for 4 weeks. Furthermore, the BMD, trabecular area, number and perimeter, calcareous nodule counts, and OPG/RANKL ratio were higher in the HA-UCMSC treatment group than in the UCMSC treatment group. The osteogenic and adipogenic differentiation of dexamethasone-treated BMMSCs was enhanced after the coculture of UCMSCs and HA-UCMSCs, and the HA-UCMSC group exhibited better effects than the UCMSC coculture group. The protein expression of WNT, β-catenin, and runx2 was upregulated, and IFN-γ and IL-17 expression was downregulated after UCMSC and HA-UCMSC treatment. HA-UCMSCs have a stronger therapeutic effect on osteoporosis compared with that of UCMSCs. These effects include an improved bone structure, increased BMD, an increased number and perimeter of trabeculae, and enhanced osteogenic differentiation of BMMSCs via activation of the WNT/β-catenin pathway and inhibition of inflammation.</p>.

Basophil-Derived IL-4 Production and Its Potential Pro-Tumoural Role in Th2-Polarisation Within Sentinel Lymph Nodes of Primary Cutaneous Melanoma.

Chronic inflammation in the tumour microenvironment (TME) via Th2-polarisation promotes melanoma progression and metastasis, making it a target for immunotherapy. Interleukin (IL)-4 is considered essential for Th2-polarisation in the TME; however, its source remains unknown. Basophils have been postulated as one of its sources. Basophil-derived IL-4 contributes to Th2-polarisation in parasitic infections and allergic diseases and has been implicated in tumour immunity. To identify basophil infiltration into the TME of human melanoma skin lesions and sentinel lymph nodes (SLNs) and demonstrate that basophils produce IL-4. Immunohistochemistry (IHC) with a basophil-specific BB1 antibody and insitu hybridisation. Basophils tended to infiltrate skin lesions at Stage II or later. Higher numbers of infiltrating basophils correlated with the Breslow depth and a shorter progression-free survival, indicating an association with poor prognosis. In SLNs, basophils infiltrated at early stages without metastasis (Stages I and II), with the number of infiltrating basophils being significantly higher in Stage II than in Stage I. IHC revealed that IL-4 levels were also significantly elevated in Stage II SLNs compared to Stage I SLNs. Furthermore, a positive correlation was observed between the number of basophils infiltrating SLNs and IL-4 expression. Insitu hybridisation confirmed that basophils expressed IL4. These findings are consistent with previous reports of early-stage melanoma SLNs having a Th2-environment and suggest that basophil-derived IL-4 may contribute to a metastasis-promoting environment in SLNs through Th2-polarisation. Basophils may represent potential immunotherapeutic targets for pro-tumour changes that occur in SLNs in early-stage melanoma.

The role of 5-hydroxytryptamine on expulsion of Trichinella spiralis during the intestinal stage.

During the intestinal stage of Trichinella spiralis (T. spiralis) infection, it can stimulate host's intestinal peristalsis to expulse worms. 5-hydroxytryptamine (5-HT) is a neurotransmitter which can regulate the contraction of intestinal smooth muscle. IL-33 specifically binds to ST2 receptor to promote the secretion of 5-HT by intestinal enterochromaffin cells. However, it remains unclear whether the host is able to modulate the secretion of 5-HT to expulse worms through the IL-33-ST2 signaling pathway during the intestinal stage of T. spiralis infection. Therefore, ST2 inhibitor iST2 was used in a T. spiralis infected mouse model and MODE-K cells to analyze the role of IL-33-ST2 signaling pathway in the secretion of 5-HT during the intestinal phase of T. spiralis infection. The results indicated that the expression of ST2, IL-33, and TPH1(tryptophan hydroxylase 1, the rate-limiting enzyme in the biosynthesis of 5-HT) in the small intestine were increased during the intestinal phase of T. spiralis infection. Meanwhile the levels of secretory 5-HT and IL-33 in the small intestine were significantly increased. After iST2 treatment, the level of 5-HT was significantly decreased, resulting in diminished worms expulsion capability. The decrease of 5-HT was observed in MODE-K cells treated with excretory-secretory products of T. spiralis post iST2 treatment. The above results demonstrated that IL-33-ST2 signaling pathway might play a crucial role in promoting the secretion of 5-HT which enhancing the ability of the intestine to expulse worms during the intestinal stage of T. spiralis.

Infiltration of innate and adoptive lymphoid cells in 4T1 and MC4-L2 breast cancer models.

Innate lymphoid cells (ILCs) are tissue-resident lymphocytes that have vital roles in activating further immune responses. However, due to their tumor-induced diversity, we decided to examine ILCs, T cells, and the associated cytokines in mouse models of breast cancer. 4T1 and MC4-L2 cells were used to induce triple-negative and hormone-receptor-positive breast cancer, respectively. Tumor tissue was resected at early and late stages of tumor growth and used for further analysis. Total RNA was extracted and used in Real-Time PCR to analyze the expression of IFN-γ, IL-4, IL-10, IL-13, and IL-22. Tumor tissue was digested and used in a flow cytometric assay. H&E staining was used to examine the pathology of tumor progression. Both tumor models showed a notable increase in T-cell frequency at the early stage of tumor growth. However, as the tumors progressed, the frequency of T cells significantly decreased, while the ILC component exhibited a significant increase in tumor progression. Gene analysis indicated a significant increase in the inflammatory to anti-inflammatory cytokine ratio during tumor progression in the tumor model. In contrast, this ratio was considerably reduced in advanced MC4-L2 tumors. Both tumor models showed the development of invasive breast carcinoma and lung metastasis in advanced tumors. Our study highlighted the expansion of ILCs during tumor progression in two distinct breast cancer models with different immunogenicity. These findings suggest that ILCs may actively modulate the tumor microenvironment during the advanced stage of tumor growth.

Oral-Delivery Lactococcus lactis Expressing mCherry Fusion Lactoferrin Peptides against Infection of Avian Pathogenic Escherichia coli in Chickens

Avian pathogenic Escherichia coli (APEC) infections result in significant economic losses and reduced animal welfare. Historically, antibiotics and vaccinations currently control APEC infections in poultry, however, antibiotic-resistant strains and heterologous serotypes limit their effectiveness. Meanwhile, antibiotic-resistant strains can be transmitted to humans via contact with animals, food or their environment. Probiotics and antimicrobial peptides (AMPs) are potential alternatives to antibiotics and represent promising strategies to combat APEC. Bovine lactoferricin and lactoferrampin possess anti-bacterial, anti-inflammatory, and anti-oxidant properties. Lactococcus lactis (L. lactis) is an excellent vector for delivering recombinant proteins. In this research, we generated a recombinant L. lactis strain MG1363 expressing lactoferrin peptides, which was labeled with a fluorescent marker mCherry and lacked an antibiotic resistance gene (LL-EFLmC). Our investigation focused on the impact of LL-EFLmC strain on the gut microbiota composition and avian pathogenic E. coli O78 challenge. Our findings indicate that LL-EFLmC exhibits inhibitory effects against APEC-O78 and Staphylococcus aureus CVCC26003 (S. aureus CVCC26003) in vitro. Furthermore, the inclusion of LL-EFLmC in chicken feed significantly improved the average daily intake and gain to feed ratio. Additionally, LL-EFLmC treatment resulted in a significant increase in serum IgG and intestinal mucus SIgA levels. Administration of LL-EFLmC was found to effectively suppress APEC-O78 infection and mitigate the expression of pro-inflammatory cytokines, including IL-1β, IL-12, IFN-γ, and TNF-α. Additionally, 16S rDNA sequencing data revealed that LL-EFLmC was able to restore the intestinal flora that had been disrupted by APEC-O78. These findings suggest that LL-EFLmC may serve as a promising feed additive and antibiotic alternative in chicken production, due to its potential to enhance immune regulation, promote growth, and confer resistance against APEC-O78 infection.

Egg allergen-specific T-cell and cytokine responses in healthy and egg-allergic children naturally tolerating baked egg.

Type 1 regulatory T (Tr1) cells are critical players in maintaining peripheral tolerance, by producing high IL-10 levels in association with inducible T-cell co-stimulator (ICOS) expression. Whether these cells play a role in naturally acquired baked egg tolerance is unknown. Evaluate frequencies of egg-responsive Tr1 and Th2 cells in egg-allergic children that naturally acquired baked egg tolerance (BET) versus non-egg-allergic (NEA) children. Peripheral blood mononuclear cells from 70 natural BET and 15 NEA children were stimulated for 7 days with ovalbumin and ovomucoid. By flowcytometry, egg-responsive Tr1 cells were identified by co-expression of CD49b and LAG3, and Th2 cells by expression of CD49b but absence of LAG3. Seven-day cultured supernatant was analyzed for Th1, Th2, Tr1, and Th17 cytokines by MSD. Natural BET children had a higher percentage of egg-responsive Th2 cells vs. NEA children (6.75% vs. 10.35%, p = .006). No significant difference was found in frequencies of egg-responsive Tr1 cells between NEA and natural BET children (11.40% vs. 12.55%, p = .42), although Tr1-related IL-10 and IL-21 production was higher in BET children. Interestingly, egg-responsive Tr1 cells from NEA children expressed higher ICOS levels vs. natural BET children (97.90 vs. 88.20, p < .0001). Supernatant from natural BET children showed elevated levels of Th2 cytokines IL-5, IL-9 and IL-13 and Th17 cytokine IL-17A. Natural BET children maintain increased egg-specific Th2 responses, along with comparable proportions of egg-responsive Tr1 cells exhibiting higher IL-10 but lower ICOS expression in comparison with NEA children.

Absolute eosinophil count and expression analyses of cytokine genes in Haemonchus contortus resistant Malpura sheep: Role of TH1/TH2 cytokine dichotomy.

A strong Th2-type immune response against Haemonchus contortus infection in genetically resistant sheep provide immunity. The objective of present study was to correlate mean faecal egg counts (FECs), absolute eosinophil counts and Th1/Th2 gene expression in resistant (R) and susceptible (S) Malpura sheep. In spite of no anthelmintic treatment in R line, on majority of the months, mean FECs remained significantly (P<0.05) lower compared to S line where anthelmintic treatment was given in September every year. R sheep possess a smaller number of blood eosinophils in the majority of months as compared with S sheep and a positive correlation has been observed between absolute eosinophil counts and mean FEC. In the condition, when FEC remain similar in both the lines (R and S), significantly (P<0.05) up-regulated expression of IL-5 was observed in R sheep compared with S sheep however when FEC is hugely enhanced; IL-2, IL-6, IL-12 and IL-13 gene expression was significantly (P<0.05) up-regulated in R sheep as compared to S sheep which is dependent on season and parasite load.

Combined PD-1 and IL-10 blockade reinvigorates mucosal CD8+T exhaustion and relieves liver damage after intestinal ischemia reperfusion attack

Currently, impairments in gut mucosal immunity following intestinal ischemia reperfusion (IR) remain unclear. Mucosal CD8+T cells are critical for host defense against bacterial translocation from the gut lumen, and exhausted T cells lose robust effector functions. The present study was designed to verify the hypothesis that intestinal IR leads to mucosal CD8+T cell exhaustion, and that reinvigoration of exhausted CD8+T cell attenuates IR-induced bacterial translocation and liver damage. The intestinal IR model was performed through clamping the superior mesenteric artery in mice. The percent of exhausted CD8+T cells and the effector function of CD8+T cells were examined to determine the occurrence of intestinal mucosal CD8+T cell exhaustion. Subsequently, PD-1 blockade or combined PD-1 and IL-10 blockade was respectively used to reinvigorate exhausted CD8+T cells. Serum biomarkers, bacterial RNA and colonies, and inflammatory factors were examined to determine bacterial translocation and liver damage. The results indicated that intestinal IR induced CD8+T cell exhaustion in mucosal tissues, as evidenced by increased PD-1+ and PD-1+LAG-3+CD8+T cells and decreased IL-2 and TNF-α expression in CD8+T cells. Combined PD-1 and IL-10 blockade, but not PD-1 blockade alone, reinvigorated CD8+T cell exhaustion, as evidenced by increased generation of exhausted CD8+T cells with cytotoxicity and effector function, and elevated production of IFN-γ. Moreover, combined blockade significantly reduced the translocation of gut bacteria and injury to the liver after IR. In conclusion, intestinal IR leads to mucosal CD8+T cell exhaustion. Combined PD-1 and IL-10 blockade reinvigorates exhausted CD8+T cells, and ameliorates bacterial translocation and liver damage following IR.

The role of probiotics in restoring the Th1 to Th2 ratio in women experiencing recurrent implantation failure; a double-blind randomized clinical trial.

Among the complex causes of infertility, Recurrent Implantation Failure (RIF) stands out as a challenging condition. Immunological aberrations are closely implicated in RIF, particularly the imbalance between T helper 1 (Th1) and T helper 2 (Th2) cytokines. Interest in harnessing probiotics to enhance fertility outcomes in RIF-affected women is growing. This study aimed to investigate the potential of probiotics in restoring the Th1 to Th2 ratio and enhancing implantation outcomes in women experiencing RIF. A double-blinded randomized controlled trial enrolled 50 women with a record of at least three RIFs and 50 women with successful pregnancies as a control group in our study. RIF patients were randomly assigned to either the probiotic intervention group (n=25) or the placebo group (n=25). The probiotic group administered two tablets per day for 6months the probiotic tablets that contained prebiotic. At the same time, the placebo group received an identical-looking placebo. Flow cytometry technique was used to evaluate Th1 and Th2 cell frequencies. Gene expression of IL-4, IL-10, TNF-α and IFN-ɣ was analyzed using QRT-PCR. Serum concentrations of IL-4, IL-10, TNF-α and IFN-ɣ cytokines were evaluated using the ELISA technique. Flow cytometry analysis revealed significantly higher Th1 cell percentages in RIF patients compared to healthy controls, while healthy controls exhibited more significant Th2 cell proportions. Probiotic intervention led to a reduction in Th1 cells and an increase in Th2 cells in RIF patients. ELISA analysis indicated higher proinflammatory and lower anti-inflammatory cytokines compared to controls. After probiotic treatment, TNF-α and IFN-ɣ levels decreased, while IL-10 and IL-4 levels increased in RIF patients. QRT-PCR analysis showed no significant differences in cytokine gene expression between RIF patients before intervention. After probiotic therapy, pro-inflammatory cytokine expression decreased, and anti-inflammatory cytokine expression increased. Placebo treatment resulted in limited changes. Probiotic intervention effectively modulated the Th1 to Th2 ratio in RIF patients, evidenced by reduced Th1 cell percentages, enhanced Th2 cell populations, and cytokine level adjustments. The probiotic intervention improved implantation outcomes in women with RIF, as evidenced by a higher clinical pregnancy rate in the treatment group compared to the placebo group (p=0.037). These findings highlight the potential of probiotics in restoring immune balance and improving implantation outcomes in women with RIF.

Artemisitene ameliorates carbon tetrachloride-induced liver fibrosis by inhibiting NLRP3 inflammasome activation and modulating immune responses.

Artemisitene (ATT), an artemisinin (ART) analog retaining the endoperoxide moiety and incorporating an additional α, β-unsaturated carbonyl structure, exhibits enhanced biological activities. However, its therapeutic effects on liver fibrosis remain unclear. In this study, we demonstrated that ATT significantly alleviated liver inflammation and fibrosis induced by carbon tetrachloride (CCL4) in mice. ATT treatment markedly reduced the count of neutrophils in the liver, as well as macrophages in both the liver and spleen. Additionally, the frequencies of Th2 and Th17 cells were significantly lowered, while Th1 cells frequency and the Th1/Th2 index were notably increased. The frequency of ILC2 cells, correlated with ST2 and IL-33 expression levels, was also significantly lowered. Consistently, ATT inhibited NLRP3 inflammasome activation, which was positively associated with AST and ALT levels, and with the count of Neutrophils, macrophages, and ILC2 cells, but negatively correlated with Th1frequeny. Furthermore, liver fibrosis severity showed a significant positive correlation with neutrophil and Th17 cell counts in the liver, and a negative correlation with Th1 cell count and the Th1/Th2 index. Therefore, ATT alleviated CCL4-induced mice liver fibrosis through NLRP3 inflammasome inhibition and immunomodulation.

Early life environmental enrichment yields resilience to selected behavioural and brain responses to 5-fluorouracil in mice.

Chemotherapy remains the primary treatment modality for multiple cancer types, but the cytotoxicity of chemotherapeutic drugs often leads to persistent psychological disturbances that undermine daily function. Minimizing such unwanted effects is challenging in the rehabilitation/prehabilitation of cancer survivors, hence the impetus to identify modifiable external factors capable of improving the recovery process. The importance of social stimulation has been demonstrated in a mouse model showing that grouped housing lowered the likelihood of developing mood disturbance following exposure to chemotherapeutic drugs compared with isolated housing. Social impoverishment thus constitutes a risk factor, and social enrichment may be protective. However, the potential benefits of conventional environmental enrichment that entails extensive sensory and physical stimulation have remained untested in mice. Using C57BL/6 mice, we investigated this research gap by introducing environmental enrichment from an early age (at weaning) to maximize its resilience potential and delaying exposure to the common chemotherapeutic drug, 5-fluorouracil (5-FU), until adulthood (10 weeks old), which comprised six cycles of injections at 40 mg/kg/day × 5 days per fortnight. Our results showed that enriched housing nullified the elevation in anxiety behaviour and proliferation of hippocampal microglial cells caused by chronic 5-FU exposure. Enriched housing also lowered hippocampal IL-17 expression, effectively buffered against the stimulated release of IL-17 by 5-FU. These data extended the potential benefits of social engagement and an active lifestyle in easing the burdens of chemotherapy. Notwithstanding, the negative impacts of 5-FU on hippocampal neurogenesis and musculoskeletal properties were only notable in the enriched mice, suggesting that while environmental enrichment can buffer against certain psychological side effects, the enhanced adaptive plasticity may also increase the susceptibility to specific antineoplastic effects of chemotherapy.

Dendritic Cells Promote the Differentiation of ILCs into NCR−ILC3s in the Lungs of Mice Exposed to Cigarette Smoke

The involvement of Group 3 innate lymphoid cells (ILC3s) and dendritic cells (DCs) in chronic lung inflammation has been increasingly regarded as the key to understand the inflammatory mechanisms of smoke-related chronic obstructive pulmonary disease (COPD). However, the mechanism underlying the engagement of both remains unclear. Our study aimed to explore NCR−ILC3 differentiation in the lungs of mice exposed to cigarette smoke (CS) and to further investigate whether DCs activated by CS exposure contribute to the differentiation of ILCs into NCR−ILC3s. The study involved both in vivo and in vitro experiments. In the former, the frequencies of lung NCR−ILC3s and NKp46−IL-17A+ ILCs and the expression of DCs, CD40, CD86, IL-23, and IL-1β quantified by flow cytometry were compared between CS-exposed mice and air-exposed mice. In the latter, NKp46−IL-17A+ ILC frequencies quantified by flow cytometry were compared after two cocultures, one involving lung CD45+Lin−CD127+ ILCs sorted from air-exposed mice and DCs sifted by CD11c magnetic beads from CS-exposed mice and another including identical CD45+Lin−CD127+ ILCs and DCs from air-exposed mice. The results indicated significant increases in the frequencies of NCR−ILC3s and NKp46−IL-17A+ ILCs; in the expression of DCs, CD40, CD86, IL-23, and IL-1β in CS-exposed mice; and in the frequency of NKp46−IL-17A+ ILCs after the coculture with DCs from CS-exposed mice. In conclusion, CS exposure increases the frequency of lung ILCs and NCR−ILC3s. CS-induced DC activation enhances the differentiation of ILCs into NCR−ILC3s, which likely acts as a mediating step in the involvement of NCR-ILC3s in chronic lung inflammation.

Cytokine-armed pyroptosis induces antitumor immunity against diverse types of tumors

AbstractInflammasomes are defense complexes that utilize cytokines and immunogenic cell death (ICD) to stimulate the immune system against pathogens. Inspired by their dual action, we present cytokine-armed pyroptosis as a strategy for boosting immune response against diverse types of tumors. To induce pyroptosis, we utilize designed tightly regulated gasdermin D variants comprising different pore-forming capabilities and diverse modes of activation, representing a toolbox of ICD inducers. We demonstrate that the electrogenic transfer of ICD effector-encoding plasmids into mouse melanoma tumors when combined with intratumoral expression of cytokines IL-1β, IL-12, or IL-18, enhanced anti-tumor immune responses. Careful selection of immunostimulatory molecules is, however, imperative as a combination of IL-1β and IL-18 antagonized the protective effect of pyroptosis by IFNγ-mediated upregulation of several immunosuppressive pathways. Additionally, we show that the intratumoral introduction of armed pyroptosis provides protection against distant tumors and proves effective across various tumor types without inducing systemic inflammation. Deconstructed inflammasomes thus serve as a powerful, tunable, and tumor-agnostic strategy to enhance antitumor response, even against the most resilient types of tumors.

Down-regulation of interlinked inflammatory signalling cascades by ethanolic extract of Suaeda fruticosa Forssk. ex J.F. Gmel. attenuated in vivo inflammatory and nociceptive responses.

Juice and decoction of leaves of Suaeda fruticosa, a halophytic medicinal plant of Cholistan desert, is traditionally used to treat rheumatism. The current study was carried out to probe into in vivo anti-nociceptive, anti-inflammatory, and anti-arthritic potential of ethanolic extract of the whole plant of S. fruticosa (Et-SF)and its bioactive molecules. GC-MS screening of Et-SF revealed presence ofvarious bioactive compounds including phytol, thymol, n-hexadecanoic acid,farnesol, and 1-heptacosanol. DPPH in vitro radical scavengingassay demonstrated moderate antioxidant potential of Et-SF. Safety evaluation of Et-SF confirmed no lethal effects in female albino rats up to the singleoral dose of 5000mg/kg. In all invivo models, Et-SF was administered in three doses (125, 250, and 500mg/kg) and a single dose of flurbiprofen (FP) (10mg/kg). Et-SF significantly (p < 0.05) attenuated acute inflammation in carrageenan, histamine, and serotonin-induced rat paw oedema models in a time-dependent manner. Et-SF alleviated oedema, restored haematological parameters, and reduced severe pannus formation, inflammatory cell infiltration, and fibrous tissue proliferation inthe paws of CFA-induced arthritic rats.Moreover, treatment with thymol, farnesol and n-hexadecanoic acid alone and in combination also attenuated the arthritic progression in the arthritic rats indicating involvementof these compounds towards anti-arthritic potential of Et-SF. Et-SF and FP significantly (p < 0.05) down-regulated IL-1β, TNF-α, IL-6, NF-κB, and COX-2 mRNA expression, and up-regulated IL-4 and IL-10 mRNA expression in arthritic rats. Hot plate and acetic acid-induced writhing models results indicated the analgesic attributes of Et-SF in mice models. This study suggests that S. fruticosa ethanol extract may regulate the expression ofinflammatory markers involved in nociceptive, inflammatory, and arthritic disorders. Its phytochemicals could target multiple phases of these conditions at cellular and subcellular levels. Further research is needed to confirm this hypothesis.

Amelioration Effect of Lactobacillus kefiranofaciens ZW3 on Ovalbumin-Induced Allergic Symptoms in BALB/c Mice.

Previous studies have shown that supplementation with specific probiotics can be used to alleviate allergy symptoms. The purpose of this study was to evaluate the anti-allergic effects of Lactobacillus kefiranofaciens ZW3 (ZW3) in ovalbumin (OVA)-induced allergic mice. The mice were divided into six groups: the food allergy group, positive group (Lactobacillus rhamnosus GG), low-dose ZW3 group, middle-dose ZW3 group, high-dose ZW3 group, and the control group involving healthy mice. BALB/c mice were intraperitoneally injected with OVA/complete Freund's adjuvant (CFA) for allergy sensitization. Probiotics were administered orally once every two days in the probiotic-treated groups. The allergic score, serum OVA-sIgE, body mass, thymus, and spleen indexes were detected on day 22, and the relative mRNA expression of inflammatory cytokines was detected via RT-qPCR. The results suggest that the body weight and thymus index returned to normal levels; allergy scores, serum OVA-sIgE, IL-4, IL-5, and IL-10 expression decreased; and IFN-γ and IL-2 increased significantly in the ZW3 group compared with the allergy group. Furthermore, ZW3 decreased Muribaculaceae and Ruminococcaceae abundance and increased Lachnospiraceae abundance in the intestinal flora. In summary, ZW3 induced anti-allergic effects by increasing Th1 cytokines and decreasing Th2 cytokines, which can remarkably ameliorate the symptoms of an ovalbumin-induced food allergy.

Bacteroides fragilis capsular polysaccharide A ameliorates ulcerative colitis in rat by recovering intestinal barrier integrity and restoring gut microbiota.

Bacteroides fragilis (B. fragilis) is a Gram-negative, obligate anaerobic, commensal bacterium residing in the human gut and holds therapeutic potential for ulcerative colitis (UC). Previous studies have indicated that capsular polysaccharide A (PSA) of B. fragilis is a crucial component for its effectiveness, possessing various biological activities such as anti-inflammatory, anti-tumor, and immune-modulating effects. We previously isolated and characterized the B. fragilis strain ZY-312 from the feces of a healthy breastfed infant, and extracted its PSA, named TP2. In this study, we explored the impact of TP2 on colonic inflammation and delved into its potential mechanisms. Initially, we used 2,4,6-trinitrobenzenesulfonic acid (TNBS) to induce colitis in rats and found that TP2 treatment significantly ameliorated TNBS-induced weight loss, increased clinical scores, extensive ulcers, and intestinal epithelial damage in UC rats. Further analysis revealed that TP2 effectively restored the intestinal barrier integrity in UC rats by regulating the expression of Muc-2, tight junction proteins (ZO-1, occludin, claudin-1, and claudin-2), as well as apoptosis-related proteins Bcl-2, BAX, and Cleaved-Caspase-3. Additionally, TP2 suppressed the expression of pro-inflammatory cytokines TNF-α, IL-1β, IL-6, and IL23, while promoting the secretion of anti-inflammatory cytokines IL-10 and IL-22, thereby inhibiting the occurrence of inflammation. TP2 also downregulated the phosphorylation levels of AKT and PI3K, effectively inhibiting the abnormal activation of the PI3K/AKT signaling pathway. More interestingly, 16S rRNA sequencing results showed that TP2 restored the ecological imbalance of the rat intestinal microbiota, with an increase in beneficial bacteria such as Lactobacillus and Limosilactobacillus observed in the treatment group. In conclusion, TP2 through the regulation of intestinal barrier-related cells and proteins, inhibition of apoptosis, modulation of inflammation-related cytokine levels, and control of abnormal activation of the PI3K/AKT signaling pathway, restores intestinal barrier integrity. Additionally, by reshaping the ecological imbalance of the gut microbiota, TP2 ultimately alleviates ulcerative colitis in rats.

TLR7 Promotes Acute Inflammatory-Driven Lung Dysfunction in Influenza-Infected Mice but Prevents Late Airway Hyperresponsiveness.

Severe lower respiratory tract disease following influenza A virus (IAV) infection is characterized by excessive inflammation and lung tissue damage, and this can impair lung function. The effect of toll-like receptor 7 (TLR7), which detects viral RNA to initiate antiviral and proinflammatory responses to IAV, on lung function during peak infection and in the resolution phase is not fully understood. Using wild-type (WT) C57BL/6 and TLR7 knockout (TLR7 KO) mice, we found that IAV infection induced airway dysfunction in both genotypes, although in TLR7 KO mice, this dysfunction manifested later, did not affect lung tissue elastance and damping, and was associated with a different immune phenotype. A positive correlation was found between lung dysfunction and the infiltration of neutrophils and Ly6Clo patrolling monocytes at day 7 post-infection. Conversely, in TLR7 KO mice, eosinophil and CD8+ cytotoxic T cells were associated with airway hyperactivity at day 14. IL-5 expression was higher in the airways of IAV-infected TLR7 KO mice, suggesting an enhanced Th2 response due to TLR7 deficiency. This study highlights an underappreciated duality of TLR7 in IAV disease: promoting inflammation-driven lung dysfunction during the acute infection but suppressing eosinophilic and CD8+ T cell-dependent hyperresponsiveness during disease resolution.

IL-33/ST2 axis mediates diesel exhaust particles-induced mast cell activation

BackgroundMast cells are implicated in the pathogenesis and severity of asthma in children and adults. The release of proinflammatory mediators and cytokines from activated mast cells (MC) is associated with Type 2 (T2) cell-skewed inflammation.MethodsWe obtained the airway tissues of Balb/c mice with or without intra-tracheal diesel exhaust particles (DEP) instillation to measure the extent of tryptase+ MCs infiltration and interleukin (IL)-33 expression. Cultured human mast cells (HMC-1) were stimulated with DEP to determine the role of aryl hydrocarbon receptor (AhR) in mediating the synthesis and release of IL-33 and type-2 cytokines.ResultsIn the control animals, most of the MC accumulated in the submucosal vessels without expression of IL-33. Intra-tracheal DEP installation increased the number of IL-33+ MC infiltrating in the epithelial and sub-epithelial areas of mice. Human MC exposed to DEP upregulated mRNA and protein expression of IL-33. These effects were abolished by knockdown of expression of the AhR or AhR nuclear translocator (ARNT) by small interfering (si)RNA transfection. DEP also activated nuclear factor-kappa B (NF-κB) to facilitate nuclear translocation of the AhR. DEP increased MC migration and induced the synthesis and release of IL-4, IL-5, and IL-13 in MCs, and these effects were abolished by anti-ST2 antibodies.ConclusionsAirborne pollutants may activate MCs to produce IL-33 via the AhR/NF-κB pathway, leading to type 2 cytokines production and enhancing MC airway epithelium-shifted migration through the autocrine or paracrine IL-33/ST2 axis.