IL-27 attenuates airway inflammation in a mouse asthma model via the STAT1 and GADD45γ/p38 MAPK pathways

Genomic insights into pediatric intestinal inflammatory and eosinophilic disorders using single-cell RNA-sequencing

Introduction

Chronic inflammation of the gastrointestinal tissues underlies gastrointestinal inflammatory disorders, leading to tissue damage and a constellation of painful and debilitating symptoms. These disorders include inflammatory bowel diseases (Crohn's disease and ulcerative colitis), and eosinophilic disorders (eosinophilic esophagitis and eosinophilic duodenitis). Gastrointestinal inflammatory disorders can often present with overlapping symptoms necessitating the use of invasive procedures to give an accurate diagnosis.

Methods

This study used peripheral blood mononuclear cells from individuals with Crohn's disease, ulcerative colitis, eosinophilic esophagitis, and eosinophilic duodenitis to better understand the alterations to the transcriptome of individuals with these diseases and identify potential markers of active inflammation within the peripheral blood of patients that may be useful in diagnosis. Single-cell RNA-sequencing was performed on peripheral blood mononuclear cells isolated from the blood samples of pediatric patients diagnosed with gastrointestinal disorders, including Crohn's disease, ulcerative colitis, eosinophilic esophagitis, eosinophilic duodenitis, and controls with histologically healthy gastrointestinal tracts.

Results

We identified 730 (FDR < 0.05) differentially expressed genes between individuals with gastrointestinal disorders and controls across eight immune cell types.

Discussion

There were common patterns among GI disorders, such as the widespread upregulation of MTRNR2L8 across cell types, and many differentially expressed genes showed distinct patterns of dysregulation among the different gastrointestinal diseases compared to controls, including upregulation of XIST across cell types among individuals with ulcerative colitis and upregulation of Th2-associated genes in eosinophilic disorders. These findings indicate both overlapping and distinct alterations to the transcriptome of individuals with gastrointestinal disorders compared to controls, which provide insight as to which genes may be useful as markers for disease in the peripheral blood of patients.

Interleukin‑27 ameliorates allergic asthma by alleviating the lung Th2 inflammatory environment

Interleukin (IL)‑27 can inhibit the differentiation of Th2 cells and plays a role in the development of asthma. However, whether the therapeutic administration of IL‑27 in a mouse model of asthma can inhibit allergic responses remains a matter of debate. Additionally, the mechanisms through which IL‑27 ameliorates inflammatory responses in asthma are not yet fully understood. Thus, the aim of the present study was to examine the effects of IL‑27 on asthma using a mouse model and to elucidate the underlying mechanisms. For this purpose, mice received an intranasal administration of IL‑27 and the total and differential cell counts, levels of cytokines and type 1 regulatory T (Tr1) cells in the lungs were detected. The protein and mRNA levels of signal transducer and activator of transcription (STAT)1 and STAT3 were analyzed and airway remodeling was assessed. The results indicated that IL‑27 did not ameliorate airway inflammation, airway hyperresponsiveness, and airway remolding when administrated therapeutically. Preventatively, the administration of IL‑27 decreased the concentrations of Th2 cytokines and increased the number of Tr1 cells. The protein and mRNA levels of STAT1 and STAT3 were increased. Taken together, these findings demonstrate that the prophylactic administration of IL‑27 ameliorates asthma by alleviating the lung Th2 inflammatory environment through the restoration of both the STAT1 and STAT3 pathways. IL‑27 may thus prove to be useful as a novel agent for the prevention of asthma.

The dual role of IL-27 in CD4+T cells

Interleukin-27 (IL-27), a member of the IL-6/IL-12 family, has diverse regulatory functions in various immune responses, and is recognised as a potent agonist and antagonist of CD4+T cells in different contexts. However, this dual role and underlying mechanisms have not been completely defined. In the present review, we summarise the dual role of IL-27 in CD4+T cells. In particular, we aimed to decipher its mechanism to better understand the context-dependent function of IL-27 in CD4+T cells. Furthermore, we propose a possible mechanism for the dual role of IL-27. This may be helpful for the development of appropriate IL-27 treatments in various clinical settings.

Interleukin-27 Inhibits Epithelial-Mesenchymal Transition in Ovalbumin-Induced Mice Bronchial Epithelial Cells

The epithelial-mesenchymal transition (EMT) of bronchial epithelial cells is a critical mechanism involved in transforming growth factor beta 1 (TGF-β1) induced asthma airway remodeling. Previous study has shown that interleukin 27 (IL-27) attenuates EMT in alveolar epithelial cells, but its effects on the BEAS-2B human bronchial epithelial cell line EMT remain unknown. Herein, we explored the effects of IL-27 on BEAS-2B EMT in vivo and in vitro. In the in vivo experiments, we found that IL-27 nose-drip therapy alleviated airway remodeling, increased the epithelial phenotypic marker epithelial-cadherin (E-cadherin), and decreased the mesenchymal phenotypic marker alpha-smooth muscle actin (α-SMA) compared with the asthmatic control group. We also found that IL-27 suppressed the signal transducer and activator of transcription (STAT3) in the lung tissue of asthmatic mice. in vitro, TGF-β1-induced EMT changes, including downregulation of E-cadherin and upregulation of α-SMA, were suppressed by IL-27 treatment. Additionally, STAT3 phosphorylation was activated by TGF-β1, whereas IL-27 inhibited the activation of TGF-β1 induced STAT3 phosphorylation. Our findings indicated that IL-27 could inhibit airway remodeling by attenuating bronchial epithelial cell EMT in vivo and in vitro. Therefore, IL-27 may be a beneficial therapeutic option targeting asthmatic airway remodeling.

IL-30† (IL-27A): a familiar stranger in immunity, inflammation, and cancer

Over the years, interleukin (IL)-27 has received much attention because of its highly divergent, sometimes even opposing, functions in immunity. IL-30, the p28 subunit that forms IL-27 together with Ebi3 and is also known as IL-27p28 or IL-27A, has been considered a surrogate to represent IL-27. However, it was later discovered that IL-30 can form complexes with other protein subunits, potentially leading to overlapping or discrete functions. Furthermore, there is emerging evidence that IL-30 itself may perform immunomodulatory functions independent of Ebi3 or other binding partners and that IL-30 production is strongly associated with certain cancers in humans. In this review, we will discuss the biology of IL-30 and other IL-30-associated cytokines and their functions in inflammation and cancer.

Studying the ways that interleukin IL-30 regulates immune responses may provide novel insights into tumor development and inflammatory conditions. Interleukins are a diverse family of proteins involved in intercellular communications and immunity, where they can exert divergent and even opposing functions. Booki Min at Northwestern University in Chicago, USA, and co-workers reviewed the current understanding of IL-30 and its links to inflammation and cancer. IL-30 forms the IL-27 complex with the Ebi3 protein and was thought to be a surrogate for IL-27 in terms of activity. However, recent insights suggest that IL-30 may perform discrete immune modulation functions. Elevated IL-30 secretion is linked to prostate and breast cancer development. Extensive research is needed into the formation of IL-30, its associated protein interactions, and the development of a suitable animal model.

IL-27 regulates IL-4-induced chemokine production in human bronchial epithelial cells

IL-4 coordinates the Th2-type immune response in inflammatory diseases such as asthma. IL-27 can inhibit the development of both Th2 and Th1 cells. However, IL-27 can also drive naïve T cells to differentiate toward the Th1 phenotype. In this study, we investigated the effects of IL-27 on the activation of IL-4-induced human bronchial epithelial cells (BEAS-2B). Compared to controls, both IL-4 and IL-27 (25-100 ng/mL) increased the concentrations of CCL2 and IL-8 in a dose-dependent manner. However, compared to cells stimulated individually with IL-4 or IL-27, treatment with a combination of both cytokines reduced CCL2 and IL-8 concentrations in a dose- and time-dependent manner. IL-4 increased the activation of p38 MAPK, ERK1/2, STAT6 and NF-κB, while IL-27 increased the activation of p38 MAPK and ERK1/2 but not STAT6 and NF-κB. Compared to IL-4-stimulated cells, cells treated with both IL-27 and IL-4 displayed decreased activation of STAT6 and NF-κB but not ERK1/2 and p38 MAPK. Taken together, these results suggest that IL-27 plays a pro-inflammatory role when administered alone but downregulates bronchial epithelial cell activation when combined with IL-4. Therefore, IL-27 may be an interesting target for the treatment of Th2 inflammatory diseases.

Exploration of plasma interleukin-27 levels in asthma patients and the correlation with lung function

BACKGROUND

IL-27 attenuates allergic inflammation and improves lung function in mouse models of allergic asthma. However, plasma IL-27 levels of asthma patients and the association with clinical features remain poorly understood.

METHODS

This study examined plasma IL-27 protein expression in untreated asthma patients and controls, analyzed its correlation with Th2 inflammation and lung function, and evaluated the effect of corticosteroids on IL-27 expression.

RESULTS

Plasma IL-27 levels were lower in untreated asthma patients compared to controls. Plasma IL-27 levels were inversely correlated with sputum IL-5 mRNA expression in Th2^Hi group. The Th2^HiIL-27^Low subgroup suffered from the highest airway hyperresponsiveness (AHR) and the worst pulmonary function. The patients in Th2^LowIL-27^Low subgroup were less likely to be atopic and had the worst improvement of symptoms after four weeks of standard treatment. In vitro, dexamethasone could decrease the expression of IL-27 in THP-1 cell line. The majority of asthma patients had further decreased IL-27 levels after standard treatment, whereas patients with sustained high levels of IL-27 post-treatment had more blood neutrophils at baseline compared with those without.

CONCLUSIONS

The results indicate that low levels of IL-27 in peripheral blood are closely related to Th2 inflammation and lung function of asthma patients. Low IL-27 levels in combination with high Th2 inflammation identify an asthma phenotype with high AHR and substantial response to corticosteroids. Understanding of this interaction could help to elucidate the inherent inflammation heterogeneity of asthma.

Azacitidine regulates DNA methylation of GADD45γ in myelodysplastic syndromes

Background

Myelodysplastic syndrome (MDS) is a heterogeneous clonal disease originated from hematopoietic stem cells. Epigenetic studies had demonstrated that DNA methylation and histone acetylation were abnormal in MDS. Azacitidine is an effective drug in the treatment of demethylation.

Methods

RT‐PCR was performed to determine GADD45γ in 15 MDS clinical samples. Myelodysplastic syndrome cell lines SKM‐1 and HS‐5 were transfected with GADD45γ eukaryotic expression vector and/or GADD45γ shRNA interference plasmid, and treated with azacitidine. Proliferation and apoptosis were examined by CCK‐8 and Western blot analysis to confirm the function role of GADD45γ and azacitidine. The methylation level of GADD45γ gene was detected by bisulfite conversion and PCR.

Results

This study found that GADD45γ gene was down‐expressed in MDS patients' bone marrow and MDS cell lines, and the down‐regulation of GADD45γ in MDS could inhibit MDS cell apoptosis and promote proliferation. Azacitidine, a demethylation drug, could restore the expression of GADD45γ in MDS cells and inhibit the proliferation of MDS cells by inducing apoptosis, which was related to prognosis and transformation.

Conclusion

This study indicated that GADD45γ was expected to become a new target of MDS‐targeted therapy. The findings of this study provided a new direction for the research and development of new MDS clinical drugs, and gave a new idea for the development of MDS demethylation drug to realize precise treatment.

The immunomodulatory potentials of interleukin-27 in airway allergies

Allergic airway disorders such as asthma and allergic rhinitis are mainly caused by inhaled allergen-induced improper activation and responses of immune and non-immune cells. One important response is the production of IL-27 by macrophages and dendritic cells (DCs) during the early stage of airway allergies. IL-27 exerts powerful modulatory influences on the cells of innate immunity [eg neutrophils, eosinophils, mast cells, monocytes, macrophages, dendritic cells (DCs), innate lymphoid cells (ILCs), natural killer (NK) cells and NKT cells)] and adaptive immunity (eg Th1, Th2, Th9, Th17, regulatory T, CD8⁺ cytotoxic T and B cells). The IL-27-mediated signalling pathways may be modulated to attenuate asthma and allergic rhinitis. In this review, a comprehensive discussion concerning the roles carried out by IL-27 in asthma and allergic rhinitis was provided, while evidences are presented favouring the use of IL-27 in the treatment of airway allergies.

IL‑27 suppresses airway inflammation, hyperresponsiveness and remodeling via the STAT1 and STAT3 pathways in mice with allergic asthma

Type 2 cytokine-associated immunity may be involved in the pathogenesis of allergic asthma. Although interleukin 27 (IL-27) has been reported as an initiator and suppressor of T-helper 1 (Th1) and T-helper 2 (Th2) responses, respectively, its effects on the development of asthma remain unclear. In the present study, mice were induced and challenged with ovalbumin and received subsequent intranasal administration of IL-27. Total and differential cell counts were determined from Wright-Giemsa-stained cytospins, whereas the cytokine levels were detected using ELISA. In addition, the expression levels of signal transducer and activator of transcription (STAT) 1, STAT3, GATA-binding protein-3 (GATA3) and T-bet (T-box transcription factor) were analyzed in T cells by western blot analysis. Their corresponding mRNA expression levels were determined by quantitative PCR. Airway remodeling was assessed by conventional pathological techniques. The results indicated that intranasal administration of IL-27 ameliorated airway inflammation and hyperresponsiveness in an acute model of asthma. Furthermore, IL-27 prevented airway remodeling in a chronic model of asthma. Following administration of IL-27, the mRNA expression levels of STAT1 and T-bet were upregulated, while those of GATA3 were downregulated. Moreover, the phosphorylation levels of STAT1 and STAT3 were increased. Taken together, these findings demonstrated that intranasal administration of IL-27 ameliorated Th2-related allergic lung inflammation and remodeling in mouse models of asthma by repairing both the STAT1 and STAT3 pathways.

IL-27 alleviates airway remodeling in a mouse model of asthma via PI3K/Akt pathway

Purpose: Airway remodeling is one of the features of severe asthma. Previous study shows that IL-27 inhibits airway inflammation in asthmatic mice. However, the role of IL-27 on airway remodeling in OVA-induced asthmatic mice and its possible mechanism remain unclear. Methods: We established an ovalbumin (OVA)-induced asthmatic mice model. IL-27 were preventative administered to OVA-induced asthmatic mice. The total cells in Bronchoalveolar lavage fluid (BALF) and Airway hyperresponsiveness (AHR) were measured. The lung tissues were performed by Hematoxylin and eosin (HE) staining to estimate the pathological changes. Masson staining was used to observe the collagen deposition area. The expression of α-smooth muscle actin (α-SMA) and Type I collagen was measured by immunohistochemistry, western blot, and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Additionally, western blot was also used to measure the expression of phosphorylated-Akt (p-Akt) in each group. Results: IL-27 group showed significant inhibitory effect on the α-SMA and Type I collagen. The expression of p-Akt in the tissues of asthma model was increased and inhibited by IL-27. Conclusions: IL-27 can alleviate airway remodeling in OVA-induced asthmatic mice, and the mechanism may relate to PI3K/Akt pathway.

IL-27 signaling deficiency develops Th17-enhanced Th2-dominant inflammation in murine allergic conjunctivitis model

BACKGROUND

While most studies focus on pro-allergic cytokines, the protective role of immunosuppressive cytokines in allergic inflammation is not well elucidated. This study was to explore a novel anti-inflammatory role and cellular/molecular mechanism of IL-27 in allergic inflammation.

METHODS

A murine model of experimental allergic conjunctivitis (EAC) was induced in BALB/c, C57BL/6 or IL-27Rα-deficient (WSX-1^-/- ) mice by short ragweed pollen, with untreated or PBS-treated mice as controls. The serum, eyeballs, conjunctiva, cervical lymph nodes (CLNs) were used for study. Gene expression was determined by RT-qPCR, and protein production and activation were evaluated by immunostaining, ELISA and Western blotting.

RESULTS

Typical allergic manifestations and stimulated thymic stromal lymphopoietin (TSLP) signaling and Th2 responses were observed in ocular surface of EAC models in BALB/c and C57BL/6 mice. The decrease of IL-27 at mRNA (IL-27/EBI3) and protein levels were detected in serum, conjunctiva and CLN, as evaluated by RT-qPCR, immunofluorescent staining, ELISA and Western blotting. EAC induced in WSX-1^-/- mice showed aggravated allergic signs with higher TSLP-driven Th2-dominant inflammation, accompanied by stimulated Th17 responses, including IL-17A, IL-17F, and transcription factor RORγt. In contrast, Th1 cytokine IFNγ and Treg marker IL-10, with their respective transcription factors T-bet and foxp3, were largely suppressed. Interestingly, imbalanced activation between reduced phosphor (P)-STAT1 and stimulated P-STAT6 were revealed in EAC, especially WSX-1^-/- -EAC mice.

CONCLUSION

These findings demonstrated a natural protective mechanism by IL-27, of which signaling deficiency develops a Th17-type hyperresponse that further aggravates Th2-dominant allergic inflammation.

Sodium Fluoride (NaF) Induces Inflammatory Responses Via Activating MAPKs/NF-κB Signaling Pathway and Reducing Anti-inflammatory Cytokine Expression in the Mouse Liver

At present, no reports are focused on fluoride-induced hepatic inflammatory responses in human beings and animals. This study aimed to investigate the mRNA and protein levels of inflammatory cytokines and signaling molecules for evaluating the effect of different doses (0, 12, 24, and 48 mg/kg) of sodium fluoride (NaF) on inflammatory reaction in the mouse liver by using methods of experimental pathology, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis. We found that NaF in excess of 12 mg/kg caused the hepatic inflammatory responses, and the results showed that NaF activated the mitogen-activated protein kinases (MAPKs) signaling pathway by markedly increasing (p < 0.01 or p < 0.05) mRNA and protein levels of apoptosis signal-regulating kinase 1 (ASK1), mitogen-activated protein kinase kinases 1/2 (MEK1/2), extracellular signal-regulated protein kinases 1/2 (Erk1/2), mitogen-activated protein kinase kinases 4/7 (MEK4/7), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38) and mitogen-activated protein kinase kinases 3/6 (MEK3/6), and the nuclear factor-kappa B (NF-κB) signaling pathway by increasing (p < 0.01 or p < 0.05) the production of NF-κB and inhibitor of nuclear factor kappa-B kinase subunit beta (IKK-β) and reducing (p < 0.01 or p < 0.05) the production of the inhibitory kappa B (IκB). Thus, NaF that caused the hepatic inflammatory responses was characterized by increasing (p < 0.01 or p < 0.05) the production of pro-inflammatory mediators such as interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), monocyte chemotactic protein 1 (MCP-1), and cyclooxygenase-2 (COX-2) via the activation of MAPKs and NF-κB pathways, and by significantly inhibiting (p < 0.01 or p < 0.05) the production of anti-inflammatory mediators including interleukin-4 (IL-4) and transforming growth factor beta (TGF-β).

IL-27 targets Foxp3+ Tregs to mediate antiinflammatory functions during experimental allergic airway inflammation

Foxp3+ CD4 Tregs are central regulators of inflammation, including allergic inflammation in the lung. There is increasing evidence that inflammatory factors undermine adequate Treg functions and homeostasis, resulting in prolonged and exacerbated inflammation. Therefore, identifying the factors is of the utmost important. IL-27 is an antiinflammatory cytokine implicated in immune regulation and tolerance. However, the cellular mechanisms underlying IL-27-mediated immune regulation in vivo remain largely unknown. Utilizing a cockroach antigen-induced allergic inflammation model in mice, we sought to test the roles of Tregs during IL-27-mediated regulation of allergic inflammation. Intranasally delivered IL-27 significantly reduced the development of airway inflammation. Unexpectedly, the IL-27-induced reduction occurred only in the presence of Tregs. Il27ra-/- and Treg-specific Il27ra-/- mice developed severe airway inflammation, and IL-27 treatment had little impact on diminishing the inflammatory responses. IL-27-induced treatment was restored following transfer of WT Tregs but not of Tregs deficient in Lag3, a molecule induced by IL-27 in Tregs. Finally, Tregs from asthmatic patients exhibited blunted STAT1 phosphorylation following IL-27 stimulation. Taken together, our results uncover that Tregs are the primary target cells of IL-27 in vivo to mediate its antiinflammatory functions, suggesting that altered IL-27 responsiveness in Tregs may underlie inadequate Treg functions and perpetuation of inflammation.

IL-31 plays dual roles in lung inflammation in an OVA-induced murine asthma model

Interleukin 31 (IL-31) is a four-helix cytokine made predominantly by Th2 CD4⁺ T cells. It was initially identified as being associated with the promotion of atopic dermatitis, where increased levels of IL-31 levels have been found and IL-31 induced the expression of proinflammatory cytokines and chemokines in a human bronchial epithelial cell line. However, subsequent study has shown that IL-31RA knockout mice developed exacerbated type 2 inflammation in the lung following infection with Schistosoma mansoni eggs. In this study, we investigated the dynamic expression of IL-31 and IL-31RA during eight consecutive ovalbumin (OVA) challenges and measured the chemokines from lung alveolar epithelial cells induced by IL-31. In addition, we examined the effect deletion of IL-31RA has on lung inflammation and the differentiation of CD4⁺ T cells. Our results demonstrate that the expression of IL-31 and IL-31RA was elevated after each weekly OVA challenge, although slightly less of both observed after the first week of OVA challenge. IL-31 also promoted the expression of inflammatory chemokines CCL5, CCL6, CCL11, CCL16, CCL22, CCL28, CX3CL1, CXCL3, CXCL14 and CXCL16 in alveolar epithelial cells. Migration of macrophages and T cells was enhanced by culture supernatants of IL-31-stimulated alveolar epithelial cells. Lastly, and in contrast to the IL-31 results, mice deficient in IL-31RA developed exacerbated lung inflammation, increased IL-4-positive cell infiltrates and elevated Th2 cytokine responses in draining lymph nodes. The proliferation of IL-31RA^-/- CD4⁺ T cells was enhanced in vitro after anti-CD3/anti-CD28 antibody stimulation. These data indicate that IL-31/IL-31RA may play dual roles, first as an early inflammatory mediator promoting the secretion of chemokines to recruit inflammatory cells, and subsequently as a late inflammatory suppressor, limiting Th2 cytokine responses in allergic asthma.

Acupuncture Regulates the Balance of CD4+ T Cell Subtypes in Experimental Asthma Mice

OBJECTIVE

To evaluate the involvement of different CD4⁺ T cell subtypes in the anti-asthmatic effects of acupuncture in asthmatic mice.

METHODS

BALB/c mice were challenged by ovalbumin (OVA) for the establishment of experimental asthma model. Mice were divided into 4 groups by a random number table including the normal control, asthma model, acupuncture and sham acupuncture groups (14 per group). Acupoints Dazhui (GV 14), bilateral Fengmen (BL 12) and Feishu (BL 13) were selected for manual acupuncture treatment every other day for 4 weeks and Huantiao (GB 30) was selected for sham acupuncture. Airway hyperresponsiveness was examined by Buxco Pulmonary System. Pulmonary histopathology analysis was performed for inflammatory cell infiltration and mucus hypersecretion by haematoxylin eosin staining and periodic acid-Schiffstaining. Inflammatory mediators assays of serum were investigated by enzyme-linked immunosorbent assay and Bio-Plex. CD4⁺ T cell subpopulations including the expression levels of important factors in T lymphocyte polarization in lung tissue were examined by flow cytometric and Western blot analyses. Related pathways were detected by Western blot assay.

RESULTS

Compared with the OVA-induced asthma model group, acupuncture could attenuate airway hyperresponsiveness, inhibit inflammatory cell infiltration and mucus hypersecretion (P<0.05 or P<0.01). Furthermore, acupuncture increased the expressions of T-bet and Foxp3⁺, the cell numbers of CD4⁺ interferon gamma (IFN-γ)⁺ and CD4⁺ Foxp3⁺ in lung tissue and the level of Treg type cytokine interleukin (IL)-10 in serum (P<0.05 or P<0.01). Meanwhile, acupuncture reduced the RAR-related orphan receptor gamma t (RORγt) level, the cell numbers of CD4⁺ IL-17A⁺ as well as the levels of IL-5, IL-13 and IL-17A in serum (P<0.05 or P<0.01). In addition, both acupuncture and sham acupuncture could inhibit the phosphorylation of p38 and p44/42 (P<0.01).

CONCLUSION

Acupuncture could alleviate allergic airway inflammation by strengthening the activities of Th1 and Treg, thus regulating the balance of CD4⁺ T cell subtypes in experimental asthmatic mice.

Intranasal Administration of IL-27 Ameliorates Nasal Allergic Responses and Symptoms

BACKGROUND

Interleukin 27 (IL-27) is an initiator of the Th1 response and inhibits inflammatory responses. In a mouse model of asthma, administration of IL-27 reduced eosinophil numbers in bronchoalveolar lavage fluid and airway hyperresponsiveness. However, it is unclear whether administration of IL-27 can inhibit symptoms of allergic diseases and allergic rhinitis as a therapeutic agent. Therefore, we investigated the in vivo effect of IL-27 on nasal symptoms and allergic rhinitis.

METHODS

Mice sensitized and challenged with ovalbumin (OVA) antigen received intranasal administration of IL-27.

RESULTS

Intranasal administration of IL-27 significantly suppressed the number of sneezes and nasal rubbing movements, the number of eosinophils, OVA-specific T-cell responses in cervical lymph nodes, production of IL-4 and IL-5, and OVA-specific IgE in sera, compared with the administration of PBS alone. The production of IL-10 and IL-35, the percentage of CD25+Foxp3+ cells, and the gene expression of Foxp3 in mice that received intranasal administration of IL-27 were also significantly higher than those in mice that received only PBS.

CONCLUSIONS

This study showed, for the first time, that intranasal administration of IL-27 inhibited nasal allergic responses and symptoms even after the establishment of allergic rhinitis and suggested that IL-27 is useful as an intranasal therapeutic agent.

Preventative tracheal administration of interleukin-27 attenuates allergic asthma by improving the lung Th1 microenvironment

BACKGROUND

Interleukin-27 (IL-27) modulates CD4+ T-cell differentiation and function. The aim of this study is to investigate the effect and molecular mechanisms of IL-27 on the development of asthma.

METHODS

IL-27 was intranasally administered in an ovalbumin-induced asthma model, and lung mononuclear cells and different Th cell classes were detected by fluorescence-activated cell sorting. The effect and mechanisms of IL-27 on human bronchial epithelial (HBE) cells were investigated by measuring changes in chemotactic factors, cytokines, transcription factors, and signaling pathways.

RESULTS

We found that intranasal administration of IL-27 could attenuate airway inflammation and hyperresponsiveness, upregulate the type 1 T helper (Th1)-T memory (Tm) cells and regulatory T (Treg) cells subgroups of lung tissue lymphocytes, and diminish the levels of type 2 T helper (Th2) cytokines. IL-27 upregulated the expression of C-C motif chemokine ligand 2 (CCL2), CCL3, and CCL4 in HBE cells and promoted the production of chemotactic factors to attract monocyte recruitment. Recruited monocytes secondarily secreted IL-27 to influence HBE cells in a positive feedback cycle. After IL-27 intervention, signal transducer and activator of transcription 1 (STAT1) phosphorylation increased, while STAT4 and STAT6 phosphorylation declined.

CONCLUSIONS

Preventative intranasal administration of IL-27 can recruit more IL-27-secreted monocytes to the airway and change the different T-cell classes in lung. The improved Th1 environment helps to alleviate Th2-mediated allergic asthma by repairing the STAT1 pathway but not the STAT4 pathway.

Peucedanum japonicum extract attenuates allergic airway inflammation by inhibiting Th2 cell activation and production of pro-inflammatory mediators

ETHNOPHARMACOLOGICAL RELEVANCE

The root of Peucedanum japonicum Thunberg is traditionally used to treat coughs, colds, headache and inflammatory diseases in Korea and Japan. Its effects on allergic lung inflammation have not been investigated.

AIM OF THE STUDY

To investigate the anti-asthmatic effects of Peucedanum japonicum extract (PJE) using a murine model of asthma and a lipopolysaccharide (LPS)-stimulated macrophage cell line.

MATERIALS AND METHODS

Mice underwent two rounds of sensitization with ovalbumin 1 week apart followed by four intranasal ovalbumin challenges on days 13-16. The control group received saline only. Two ovalbumin-sensitized groups were orally administered vehicle or PJE (200mg/kg) 5 days a week starting 1 week before the first ovalbumin sensitization. The third group was orally administered the asthma medication Montelukast (10mg/kg) on days 12-16. All animals were sacrificed on day 17. The lungs were assessed for histological features, inflammatory cell infiltration, Th2 cell activation and GATA-binding protein-3 (GATA-3) expression. The bronchoalveolar lavage fluid (BALF) was assessed for type 2 cytokine levels. The effect of PJE on the in vitro Th2 polarization of naïve CD4⁺ splenocytes and the production of pro-inflammatory mediators and cytokines by LPS-stimulated RAW 264.7 cells was evaluated.

RESULTS

PJE treatment inhibited OVA-induced inflammatory cell infiltration, eosinophilia, Th2 activation, and GATA-3 expression in the lung, reduced the interleukin (IL)-5 and IL-13 levels in BALF, down-regulated Th2 activation in vitro, and inhibited the macrophage production of inducible nitric oxide, cyclooxygenase-2, tumor necrosis factor-α, and IL-6.

CONCLUSION

PJE attenuated allergic airway inflammation by inhibiting Th2 cell activation and macrophage production of inflammatory mediators. Peucedanum japonicum may be candidate therapy for allergic lung inflammation.

The pathophysiological role of mitochondrial oxidative stress in lung diseases

Mitochondria are critically involved in reactive oxygen species (ROS)-dependent lung diseases, such as lung fibrosis, asbestos, chronic airway diseases and lung cancer. Mitochondrial DNA (mtDNA) encodes mitochondrial proteins and is more sensitive to oxidants than nuclear DNA. Damage to mtDNA causes mitochondrial dysfunction, including electron transport chain impairment and mitochondrial membrane potential loss. Furthermore, damaged mtDNA also acts as a damage-associated molecular pattern (DAMP) that drives inflammatory and immune responses. In this review, crosstalk among alveolar epithelial cells, alveolar macrophages and mitochondria is examined. ROS-related transcription factors and downstream cell signaling pathways are also discussed. We conclude that targeting oxidative stress with antioxidant agents, such as thiol molecules, polyphenols and superoxide dismutase (SOD), and promoting mitochondrial biogenesis should be considered as novel strategies for treating lung diseases that currently have no effective treatment options.

Delivery of adipose-derived mesenchymal stem cells attenuates airway responsiveness and inflammation in a mouse model of ovalbumin-induced asthma

Adipose-derived mesenchymal stem cells (ADMSCs) possess immunomodulation property, yet their therapeutic potential in asthma is unclear. This study aimed to explore the effects of ADMSCs on airway hyperresponsiveness and inflammation in ovalbumin (OVA)-induced asthma models. The underlying mechanism(s) was also examined. BALB/c mice were sensitized with OVA on days 0, 7, and 14, followed by 8-week OVA challenge from day 22. ADMSCs were injected via tail vein on day 21. Animals were measured for airway responsiveness, lung pathology, IgE and cytokine levels in serum, cell composition in bronchoalveolar lavage fluid (BALF), gene expression in the lung, and regulatory T cells (Tregs). We found that delivery of ADMSCs decreased airway responsiveness and eosinophil counts in BALF and reduced infiltration of inflammatory cells and number of mucus-expressing goblet cells in the lung in OVA-challenged mice. OVA-evoked elevation of serum IgE levels and alteration of cytokine production in serum and BALF was significantly prevented by ADMSCs. In addition, administration of ADMSCs impaired the regulation of lung IL-10, Foxp3, IL-17, and RORγ expression by OVA challenge and restored the percentage of CD4⁺CD25⁺Foxp3⁺ Tregs in the spleen. In conclusion, ADMSCs confer protection against OVA-induced airway hyperresponsiveness and inflammation, which is associated with induction of Tregs and restoration of immune homeostasis. These findings suggest that ADMSCs may have therapeutic implications for allergic asthma.