Increased expression of TIPE2 in alternatively activated macrophages is associated with eosinophilic inflammation and disease severity in chronic rhinosinusitis with nasal polyps

Macrophages in CRSwNP: Do they deserve more attention?

Chronic rhinosinusitis (CRS) represents a heterogeneous disorder primarily characterized by the persistent inflammation of the nasal cavity and paranasal sinuses. The subtype known as chronic rhinosinusitis with nasal polyposis (CRSwNP) is distinguished by a significantly elevated recurrence rate and augmented challenges in the management of nasal polyps. The pathogenesis underlying this subtype remains incompletely understood. Macrophages play a crucial role in mediating the immune system's response to inflammatory stimuli. These cells exhibit remarkable plasticity and heterogeneity, differentiating into either the pro-inflammatory M1 phenotype or the anti-inflammatory and reparative M2 phenotype depending on the surrounding microenvironment. In CRSwNP, macrophages demonstrate reduced production of Interleukin 10 (IL-10), compromised phagocytic activity, and decreased autophagy. Dysregulation of pro-resolving mediators may occur during the inflammatory resolution process, which could potentially hinder the adequate functioning of anti-inflammatory macrophages in facilitating resolution. Collectively, these factors may contribute to the prolonged inflammation observed in CRSwNP. Additionally, macrophages may enhance fibrin cross-linking through the release of factor XIII-A (FAXIII), promoting fibrin deposition and plasma protein retention. Macrophages also modulate vascular permeability by releasing Vascular endothelial growth factor (VEGF). Moreover, they may disrupt the balance between Matrix Metalloproteinases (MMPs) and Tissue Inhibitors of Metalloproteinases (TIMPs), which favors extracellular matrix (ECM) degradation, edema formation, and pseudocyst development. Accumulating evidence suggests a close association between macrophage infiltration and CRSwNP; however, the precise mechanisms underlying this relationship warrant further investigation. In different subtypes of CRSwNP, different macrophage phenotypic aggregations trigger different types of inflammatory features. Increasing evidence suggests that macrophage infiltration is closely associated with CRSwNP, but the mechanism and the relationship between macrophage typing and CRSwNP endophenotyping remain to be further explored. This review discusses the role of different types of macrophages in the pathogenesis of different types of CRSwNP and their contribution to polyp formation, in the hope that a better understanding of the role of macrophages in specific CRSwNP will contribute to a precise and individualized understanding of the disease.

Aberrant expressions of TAM receptors are associated with postoperative recurrence in chronic rhinosinusitis with nasal polyps

OBJECTIVES

TAM receptors (TYRO3, AXL, and MER) play important roles in inflammatory responses, but their effects in chronic rhinosinusitis with nasal polyps (CRSwNP) remain elucidated. We aim to evaluate the values of TAM receptors in disease severity and postoperative recurrence of CRSwNP.

METHODS

We initially enrolled 160 patients with CRSwNP who were treated with functional endoscopic sinus surgery (FESS) and postoperative recurrence was evaluated during the follow-up period. Circulating TAM receptor levels were detected by enzyme-linked immunosorbent assay (ELISA), and tissue expressions were measured by real-time polymerase chain reaction (RT-PCR) and immunohistochemical (IHC). The relationships between TAM receptor levels and postoperative recurrence were examined.

RESULTS

A total of 150 patients completed the follow-up schedule, 49 patients experienced postoperative recurrence and the remaining 101 patients were non-recurrent. In recurrent CRSwNP patients, serum levels of TAM receptors were increased compared to those in non-recurrent patients and were positively correlated with disease severity scores (P < 0.05). Circulating TYRO3 and MER were identified as potential predictors of postoperative recurrence based on receiver operating characteristics (ROC) and Kaplan-Meier plots (P < 0.05). Furthermore, tissue TAM receptor levels, as determined by both RT-PCR and IHC, were enhanced in the recurrent group than in the non-recurrent group (P < 0.05) and were predictive of postoperative recurrence (P < 0.05). Interestingly, circulating TYRO3 and MER concentrations, as well as tissue TYRO3 expression, were found to be significantly increased in patients who experienced postoperative recurrence (P < 0.05). IHC images from the same patients revealed that TAM expressions were enhanced in the recurrent tissues compared to their baseline tissue levels.

CONCLUSIONS

Our laboratory results demonstrated that TAM receptors were increased in recurrent CRSwNP patients and associated with postoperative recurrence. Moreover, the new laboratory findings suggested that measuring circulating levels of TAM receptors might serve as a promising new approach to assess disease progression and predict the risk of postoperative recurrence.

SIRT5 exacerbates eosinophilic chronic rhinosinusitis by promoting polarization of M2 macrophage

BACKGROUND

Previous studies implied that local M2 polarization of macrophage promoted mucosal edema and exacerbated TH2 type inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP). However, the specific pathogenic role of M2 macrophages and the intrinsic regulators in the development of CRS remains elusive.

OBJECTIVE

We sought to investigate the regulatory role of SIRT5 in the polarization of M2 macrophages and its potential contribution to the development of CRSwNP.

METHODS

Real-time reverse transcription-quantitative PCR and Western blot analyses were performed to examine the expression levels of SIRT5 and markers of M2 macrophages in sinonasal mucosa samples obtained from both CRS and control groups. Wild-type and Sirt5-knockout mice were used to establish a nasal polyp model with TH2 inflammation and to investigate the effects of SIRT5 in macrophage on disease development. Furthermore, in vitro experiments were conducted to elucidate the regulatory role of SIRT5 in polarization of M2 macrophages.

RESULTS

Clinical investigations showed that SIRT5 was highly expressed and positively correlated with M2 macrophage markers in eosinophilic polyps. The expression of SIRT5 in M2 macrophages was found to contribute to the development of the disease, which was impaired in Sirt5-deficient mice. Mechanistically, SIRT5 was shown to enhance the alternative polarization of macrophages by promoting glutaminolysis.

CONCLUSIONS

SIRT5 plays a crucial role in promoting the development of CRSwNP by supporting alternative polarization of macrophages, thus providing a potential target for CRSwNP interventions.

ALOX15+ M2 macrophages contribute to epithelial remodeling in eosinophilic chronic rhinosinusitis with nasal polyps

BACKGROUND

Epithelial remodeling is a prominent feature of eosinophilic chronic rhinosinusitis with nasal polyps (eCRSwNP), and infiltration of M2 macrophages plays a pivotal role in the pathogenesis of eCRSwNP, but the underlying mechanisms remain undefined.

OBJECTIVE

We sought to investigate the role of ALOX15+ M2 macrophages in the epithelial remodeling of eCRSwNP.

METHODS

Digital spatial transcriptomics and single-cell sequencing analyses were used to characterize the epithelial remodeling and cellular infiltrate in eCRSwNP. Hematoxylin and eosin staining, immunohistochemical staining, and immunofluorescence staining were used to explore the relationship between ALOX15+ M2 (CD68+CD163+) macrophages and epithelial remodeling. A coculture system of primary human nasal epithelial cells (hNECs) and the macrophage cell line THP-1 was used to determine the underlying mechanisms.

RESULTS

Spatial transcriptomics analysis showed the upregulation of epithelial remodeling-related genes, such as Vimentin and matrix metalloproteinase 10, and enrichment of epithelial-mesenchymal transition (EMT)-related pathways, in the epithelial areas in eCRSwNP, with more abundance of epithelial basal, goblet, and glandular cells. Single-cell analysis identified that ALOX15+, rather than ALOX15-, M2 macrophages were specifically highly expressed in eCRSwNP. CRSwNP with high ALOX15+ M2THP-1-IL-4+IL-13 macrophages had more obvious epithelial remodeling features and increased genes associated with epithelial remodeling and integrity of epithelial morphology versus that with low ALOX15+ M2THP-1-IL-4+IL-13 macrophages. IL-4/IL-13-polarized M2THP-1-IL-4+IL-13 macrophages upregulated expressions of EMT-related genes in hNECs, including Vimentin, TWIST1, Snail, and ZEB1. ALOX15 inhibition in M2THP-1-IL-4+IL-13 macrophages resulted in reduction of the EMT-related transcripts in hNECs. Blocking chemokine (C-C motif) ligand 13 signaling inhibited M2THP-1-IL-4+IL-13 macrophage-induced EMT alteration in hNECs.

CONCLUSIONS

ALOX15+ M2 macrophages are specifically increased in eCRSwNP and may contribute to the pathogenesis of epithelial remodeling via production of chemokine (C-C motif) ligand 13.

sPLA2GIB Promotes PGD2 and IL-13 Production in Eosinophilic Chronic Rhinosinusitis with Nasal Polyps

OBJECTIVE

Secreted phospholipase A2 Group IB (sPLA2GIB) regulates the release of arachidonic acid, prostaglandins, and other inflammatory lipid mediators. Although it has been well involved in extensive inflammatory diseases, its specific mechanism in chronic rhinosinusitis with nasal polyps (CRSwNP) remains unclear. In this study, we investigated the role of sPLA2GIB in the pathophysiology of CRSwNP.

METHODS

Quantitative PCR, immunofluorescence staining, western blotting, and enzyme-linked immunosorbent assay (ELISA) were used to analyze the expression of sPLA2s, phospholipase A2 receptor (PLA2R), and prostaglandin D2 (PGD2) in nasal samples. Human nasal epithelial cells (HNECs) were cultured at an air-liquid interface (ALI) and stimulated with various cytokines. The human mast cell line HMC-1 was stimulated with sPLA2GIB, and the expression of PGD2 and cytokines in the culture supernatant was detected by ELISA.

RESULTS

The mRNA and protein levels of sPLA2GIB were significantly higher in eosinophilic CRSwNP than in control tissues. sPLA2GIB was predominantly expressed in the nasal epithelial cells. PLA2R mRNA and protein levels were upregulated in both eosinophilic and non-eosinophilic CRSwNP compared with the control groups. IL-4, IL-13, TNF-α, and IL-1β upregulated the expression of sPLA2GIB in ALI-cultured HNECs. sPLA2GIB induced PGD2 and IL-13 production in HMC-1 cells in a hydrolytic activity-independent manner. PGD2 protein expression was elevated in tissue homogenates of eosinophilic CRSwNP, and PGD2 upregulated the expression of IL-13 in HMC-1 cells.

CONCLUSION

Increased secretion of sPLA2GIB by epithelial cells may promote eosinophilic inflammation in CRSwNP by enhancing PGD2 and IL-13 production in mast cells via binding to PLA2R.

LEVEL OF EVIDENCE

N/A Laryngoscope, 134:1107-1117, 2024.

Deficiency of INPP4A promotes M2 macrophage polarization in eosinophilic chronic rhinosinusitis with nasal polyps

OBJECTIVE

The treatment of eosinophilic chronic rhinosinusitis with nasal polyps (E-CRSwNP) remains a challenge due to its complex pathogenesis. Inositol polyphosphate-4-phosphatase type IA (INPP4A), a lipid phosphatase, has been implicated in allergic asthma. However, the expression and function of INPP4A in E-CRSwNP remain unclear. This study aims to investigate the role of INPP4A in macrophages in E-CRSwNP.

METHODS

We assessed the expression of INPP4A in human and mouse nasal mucosal tissues via immunofluorescence staining. THP-1 cells were cultured and exposed to various cytokines to investigate the regulation of INPP4A expression and its functional role. Additionally, we established a murine nasal polyp (NP) model and administrated an INPP4A-overexpressing lentivirus evaluate its impact on NP.

RESULTS

The percentage of INPP4A + CD68 + macrophages among total macrophages decreased in the E-CRSwNP group compared to the control and the non-eosinophilic CRSwNP (NE-CRSwNP) groups, exhibiting an inverse correlation with an increased percentage of CD206 + CD68 + M2 macrophages among total macrophages. Overexpression of INPP4A led to a reduced percentage of THP-1 cells polarizing towards the M2 phenotype, accompanied by decreased levels of associated chemotactic factors including CCL18, CCL22, CCL24, and CCL26. We also validated the involvement of the PI3K-AKT pathway in the function of INPP4A in vitro. Furthermore, INPP4A overexpression in the murine NP model resulted in the attenuation of eosinophilic inflammation in the nasal mucosa.

CONCLUSIONS

INPP4A deficiency promotes macrophage polarization towards the M2 phenotype, leading to the secretion of chemokines that recruit eosinophils and Th2 cells, thereby amplifying eosinophilic inflammation in E-CRSwNP. INPP4A may exert a suppressive role in eosinophilic inflammation and could potentially serve as a novel therapeutic strategy.

Abnormal S100A8 expression associates with postoperative recurrence in chronic rhinosinusitis with nasal polyps

Objective

To investigate the role of S100A8 in chronic rhinosinusitis with nasal polyps (CRSwNP) and assess its value in predicting disease recurrence after surgery.

Methods

Thirty healthy controls (HC), 30 patients with chronic rhinosinusitis without nasal polyp (CRSsNP), and 60 patients with CRSwNP were enrolled. Serum S100A8 concentration was measured by ELISA. Immunohistochemistry (IHC), western blotting (WB), and reverse transcription-polymerase chain reaction (RT-PCR)were performed to examine tissue expression levels of S100A8. The potential values of S100A8 in predicting postoperative recurrence of CRSwNP were assessed by the receiver operating characteristic (ROC)curve.

Results

Serum S100A8 concentrations in the CRSwNP group were higher than the HC group and the CRSsNP group， especially in the recurrent CRSwNP group (P < 0.05). Serum S100A8 levels were positively correlated with peripheral blood eosinophil numbers (r = 0.263, P = 0.043) and percentages (r = 0.336, P = 0.009), tissue eosinophil percentages (r = 0.273, P = 0.035), VAS score (r = 0.385, P = 0.002) and Lund-Kennedy score (r = 0.283, P = 0.029). IHC, WB, and RT-PCR results showed tissue S100A8 expression was significantly enhanced in the CRSwNP group, especially in the recurrence group (P < 0.05). Binary regression analysis showed that serum S100A8 concentration and tissue eosinophil percentage were correlated with postoperative recurrence of CRSwNP. ROC curve analysis showed that compared with tissue eosinophil percentage, the S100A8 level had a higher value for postoperative recurrence of CRSwNP.

Conclusion

Serum and tissue S100A8 levels were elevated in patients with CRSwNP， especially in the recurrent CRSwNP patients, and were correlated with the degree of peripheral blood and tissue eosinophilic inflammation. S100A8 seemed to be a potential objective biomarker to predict the postoperative recurrence of CRSwNP.

Matrix-Mediated Delivery of Silver Nanoparticles for Prevention of Staphylococcus aureus and Pseudomonas aeruginosa Biofilm Formation in Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a chronic health condition affecting the sinonasal cavity. CRS-associated mucosal inflammation leads to sinonasal epithelial cell death and epithelial cell barrier disruption, which may result in recurrent bacterial infections and biofilm formation. For patients who fail medical management and elect endoscopic sinus surgery for disease control, bacterial biofilm formation is particularly detrimental, as it reduces the efficacy of surgical intervention. Effective treatments that prevent biofilm formation in post-operative patients in CRS are currently limited. To address this unmet need, we report the controlled release of silver nanoparticles (AgNps) with silk-elastinlike protein-based polymers (SELPs) to prevent bacterial biofilm formation in CRS. This polymeric network is liquid at room temperature and forms a hydrogel at body temperature, and is hence, capable of conforming to the sinonasal cavity upon administration. SELP hydrogels demonstrated sustained AgNp and silver ion release for the studied period of three days, potent in vitro antibacterial activity against Pseudomonas aeruginosa (**** p < 0.0001) and Staphylococcus aureus (**** p < 0.0001), two of the most commonly virulent bacterial strains observed in patients with post-operative CRS, and high cytocompatibility with human nasal epithelial cells. Antibacterial controlled release platform shows promise for treating patients suffering from prolonged sinonasal cavity infections due to biofilms.

Different exposure modes of PM2.5 induces bronchial asthma and fibrosis in male rats through macrophage activation and immune imbalance induced by TIPE2 methylation

Exposure to PM_2.5 can aggravate the occurrence and development of bronchial asthma and fibrosis. Here, we investigated the differences in bronchial injury caused by different exposure modes of PM_2.5 (high concentration intermittent exposure and low concentration continuous exposure), and the mechanism of macrophage activation and respiratory immune imbalance induced by PM_2.5, leading to bronchial asthma and airway fibrosis using animal and cell models. A "PM_2.5 real-time online concentrated animal whole-body exposure system" was used to conduct PM_2.5 respiratory exposure of Wistar rats for 12 weeks, which can enhance oxidative stress in rat bronchus, activate epithelial cells and macrophages, release chemokines, recruit inflammatory cells, release inflammatory factors and extracellular matrix, promote bronchial mucus hypersecretion, inhibit the expression of epithelial cytoskeletal proteins, destroy airway barrier, and induce asthma. Furthermore, PM_2.5 induced M2 polarization in lung bronchial macrophages through JAK/STAT and PI3K/Akt signaling pathways, and compared with low concentration continuous exposure, high concentration intermittent exposure of PM_2.5 could regulate significantly higher expression of TIPE2 protein through promoter methylation of TIPE2 DNA, thereby activating PI3K/Akt signaling pathway and more effectively inducing M2 polarization of macrophages. Additionally, activated macrophages release IL-23, and activated epithelial cells and macrophages released TGF-β1, which promoted the differentiation of Th17 cells, triggered the Th17 dominant immune response, and activated the TGF-β1/Smad2 signaling pathway, finally causing bronchial fibrosis. Moreover, when the total amount of PM_2.5 exposure was equal, high concentration-intermittent exposure was more serious than low concentration-continuous exposure. In vitro experiments, the co-culture models of PM_2.5 with BEAS-2B, WL-38 and rat primary alveolar macrophages further confirmed that PM_2.5 could induce the macrophage activation through oxidative stress and TIPE2 DNA methylation, and activate the TGF-β1/Smad2 signaling pathway, leading to the occurrence of bronchial fibrosis.

TIM-4 in macrophages contributes to nasal polyp formation through the TGF-β1–mediated epithelial to mesenchymal transition in nasal epithelial cells

Chronic rhinosinusitis with nasal polyps (CRSwNP) is caused by prolonged inflammation of the paranasal sinus mucosa. The epithelial to mesenchymal transition (EMT) is involved in the occurrence and development of CRSwNP. The T-cell immunoglobulin domain and the mucin domain 4 (TIM-4) is closely related to chronic inflammation, but its mechanism in CRSwNP is poorly understood. In our study, we found that TIM-4 was increased in the sinonasal mucosa of CRSwNP patients and, especially, in macrophages. TIM-4 was positively correlated with α-SMA but negatively correlated with E-cadherin in CRS. Moreover, we confirmed that TIM-4 was positively correlated with the clinical parameters of the Lund-Mackay and Lund-Kennedy scores. In the NP mouse model, administration of TIM-4 neutralizing antibody significantly reduced the polypoid lesions and inhibited the EMT process. TIM-4 activation by stimulating with tissue extracts of CRSwNP led to a significant increase of TGF-β1 expression in macrophages in vitro. Furthermore, coculture of macrophages and human nasal epithelial cells (hNECs) results suggested that the overexpression of TIM-4 in macrophages made a contribution to the EMT process in hNECs. Mechanistically, TIM-4 upregulated TGF-β1 expression in macrophages via the ROS/p38 MAPK/Egr-1 pathway. In conclusion, TIM-4 contributes to the EMT process and aggravates the development of CRSwNP by facilitating the production of TGF-β1 in macrophages. Inhibition of TIM-4 expression suppresses nasal polyp formation, which might provide a new therapeutic approach for CRSwNP.

A Potential Role of B7-H4 Expression in Predicting the Recurrence of Chronic Rhinosinusitis with Nasal Polyps

Background

Chronic rhinosinusitis with polyps (CRSwNP) is a common chronic inflammatory disease of the nasal cavity and sinuses with a high rate of postoperative recurrence. In this study, we aim to investigate the expression of B7-H4 in CRSwNP and its association with postoperative recurrence.

Methods

A total of 80 CRSwNP patients, including 40 primary CRSwNP (pCRSwNP) patients and 40 recurrent CRSwNP (rCRSwNP) patients, 27 chronic rhinosinusitis without polyps (CRSsNP) and 32 healthy controls (HC) were enrolled in this study, and the serum, nasal polyps and middle turbinate tissue samples were collected. Peripheral and tissue B7-H4 expressions were detected by enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence, and their clinical values in predicting postoperative recurrence of CRSwNP were evaluated.

Results

We identified significantly higher tissue B7-H4 mRNA levels in the CRSwNP group than in the HC group, and elevated B7-H4 levels were associated with tissue eosinophil count and percentage (r = 0.469, P < 0.001; r = 0.521, P < 0.001). B7-H4 mRNA and protein levels were significantly higher in the rCRSwNP group than the pCRSwP group. Multivariate analysis and receiver operating characteristic (ROC) curves showed that tissue B7-H4 levels were associated with postoperative recurrence in patients with CRSwNP (P < 0.05). In addition, serum B7-H4 levels were significantly increased in the CRSwNP group than the CRS and HC groups, especially in the rCRSwNP group (P < 0.05), and the ROC curve presented a predictive ability of serum B7-H4 in predicting postoperative recurrence.

Conclusion

Our results indicated that B7-H4 level was clearly enhanced in CRSwNP patients and associated with postoperative recurrence. Serum B7-H4 might serve as a simple and convenient biomarker for early predicting postoperative recurrence in CRwNP patients.

Construction and analysis of a ceRNA network and patterns of immune infiltration in chronic rhinosinusitis with nasal polyps: based on data mining and experimental verification

Recent studies have revealed the significant role of the competing endogenous RNA (ceRNA) network in human diseases. However, systematic analysis of the ceRNA mechanism in chronic rhinosinusitis with nasal polyps (CRSwNP) is limited. In this study, we constructed a competitive endogenous RNA (ceRNA) network and identified a potential regulatory axis in CRSwNP based on bioinformatics analysis and experimental verification. We obtained lncRNA, miRNA, and mRNA expression profiles from the Gene Expression Omnibus. After analysis of CRSwNP patients and the control groups, we identified 565 DE-lncRNAs, 23 DE-miRNAs, and 1799 DE-mRNAs by the DESeq2 R package or limma R package. Enrichment analysis of 1799 DE-mRNAs showed that CRSwNP was associated with inflammation and immunity. Moreover, we identified 21 lncRNAs, 8 miRNAs and 8 mRNAs to construct the lncRNA-miRNA-mRNA ceRNA network. A potential MIAT/miR-125a/IRF4 axis was determined according to the degree and positive correlation between a lncRNA and its competitive endogenous mRNAs. The GSEA results suggested that IRF4 may be involved in immune cell infiltration. The validation of another dataset confirmed that MIAT and IRF4 were differentially expressed between the CRSwNP and control groups. The area under the ROC curve (AUC) of MIAT and IRF4 was 0.944. The CIBERSORT analysis revealed that eosinophils and M2 macrophages may be involved in the CRSwNP process. MIAT was correlated with dendritic cells and M2 macrophages, and IRF4 was correlated with dendritic cells. Finally, to validate the key genes, we performed in-silico validation using another dataset and experimental validation using immunohistochemistry, immunofluorescence, and Western blot. In summary, the constructed novel MIAT/miR-125a/IRF4 axis may play a critical role in the development and progression of CRSwNP. We believe that the ceRNA network and immune cell infiltration could offer further insight into novel molecular therapeutic targets for CRSwNP.

TIPE2 May Target the Nrf2/HO-1 Pathway to Inhibit M1 Macrophage-Related Neutrophilic Inflammation in Asthma

Purpose

Although recent studies have highlighted the link of TIPE2 and asthma airway inflammation, its roles and molecular mechanisms in different asthma inflammatory phenotypes remain largely unknown. We evaluated sputum TIPE2 expression level and its correlation with different asthma phenotypes. Additionally, we explored the roles and mechanism of TIPE2 in M1 polarization of macrophages.

Methods

A total of 102 asthma patients who underwent sputum induction were enrolled to evaluate the expression level of TIPE2 and its association with different asthma phenotypes. To explore the roles and mechanism of TIPE2 in M1 polarization of macrophages, THP-1 monocytes stimulated with phorbol-12-myristate-13-acetate, were used as a model of undifferentiated (M0) macrophages, and M0 macrophages were treated with lipopolysaccharide to induce M1 macrophages.

Results

The sputum TIPE2 level was significantly lower in patients with neutrophilic asthma (NA) and higher in patients with eosinophilic asthma (EA) compared with patients with paucigranulocytic asthma. The levels of IL-1β, TNF-α and IL-6 were highest in NA compared with other groups. TIPE2 levels in sputum negatively correlated with IL-1β and TNF-α levels but positively correlated with IL-4, IL-5, IL-13, and IL-10 levels (P < 0.05). In vitro, TIPE2 enhanced Nrf2/HO-1 pathway activation in macrophages and inhibited LPS-induced M1 macrophage differentiation and related cytokine release. Further analysis showed that the Nrf2 inhibitor ML385 weakened TIPE2-induced activation of the Nrf2/HO-1 pathway, as well as TIPE2-induced suppression in M1 polarization of macrophage and inflammatory cytokines secretion.

Conclusions

TIPE2 expression level was highly down-regulated in NA and was negatively correlated with inflammatory factors (IL-1β and TNF-α). Aberrant expression of TIPE2 may target the Nrf2/HO-1 pathway to inhibit M1 macrophage–related neutrophilic inflammation in asthma.

Zhike Pingchuan Granule suppresses interleukin (IL)-6 or the medium of M2 macrophages induced apoptosis in human bronchial epithelial cells

The aim of this study was to explore the effects and action mechanism of Zhike Pingchuan Granule in human bronchial epithelial cells induced by IL-6 or the supernatant of M2. Upon IL-6 stimulation at different doses, Cell Counting Kit-8 (CCK8) assay and flow cytometry were, respectively, utilized to detect the cell viability and apoptosis levels of 16-HBE cells. ELISA and Western blot were, respectively, used to analyze the inflammatory markers and JAK2/STAT3 signals. Immunofluorescence assay was performed to identify M0 and M2 cells. As shown in results, ZKPC perturbed the expression of IL-6 inducible genes important for apoptosis, oxidative and inflammatory response, which was enhanced by JAK2 inhibitor. Besides the inhibitory effects on the phosphorylation levels of JAK2/STAT3, ZKPC markedly increased cell viability and reduced apoptosis in human bronchial epithelial cells (16-HBE) cultured in the supernatant of M2 cells. Collectively, ZKPC could inhibit the IL-6-induced JAK/STAT3 signaling cascade, increase cell viability and decrease apoptosis induced by the supernatant of M2. A more comprehensive understanding of the action mechanism of ZKPC on JAK2/STAT3 signaling pathway in human bronchial epithelial cells induced by IL-6 or M2 supernatant will enable ZKPC development in the control of asthma.

Predictive value of clinical characteristics in eosinophilic chronic rhinosinusitis with nasal polyps: A cross-sectional study in the Chinese population

BACKGROUND

Eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) is a refractory subtype of chronic rhinosinusitis with nasal polyps (CRSwNP), with clinical characteristics differing from those of non-ECRSwNP. We aimed to explore the predictive value of clinical characteristics, including medical history, symptoms, and signs, prior to ECRSwNP diagnosis, and to develop a nomogram for use in clinical practice.

METHODS

A total of 502 patients with CRSwNP were enrolled. Based on the degree of eosinophilic infiltration in nasal polyps (NPs), patients were classified as ECRSwNP or non-ECRSwNP group. Participants' demographic characteristics, asthma history, severity of nasal symptoms (nasal obstruction, rhinorrhea, hyposmia, and facial pain/headache) according to the visual analog scale, and nasal polyp scores based on polyp scoring system were recorded. Logistic regression analysis was performed to screen for independent risk factors, and a model nomogram was constructed.

RESULTS

The percentage of asthmatic patients and the hyposmia, rhinorrhea, and total nasal symptom scores were significantly higher in ECRSwNP patients than that in non-ECRSwNP patients. The nasal polyp score was lower in the eosinophilic group than that in the non-eosinophilic group. Logistic regression analysis revealed that asthma history and hyposmia, rhinorrhea and nasal polyp scores were independent predictors of ECRSwNP. A nomogram consisting of these four independent risk factors was constructed, and its C-index was 0.808 (95% CI, 0.771 to 0.846).

CONCLUSIONS

The nomogram based on asthma history and olfactory, rhinorrhea, and nasal polyp scores could help predict ECRSwNP, providing a simple, fast, and practical way to distinguish ECRSwNP from non-ECRSwNP cases in clinical practice.

International consensus statement on allergy and rhinology: rhinosinusitis 2021

I.

EXECUTIVE SUMMARY

BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document.

METHODS

ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary.

RESULTS

ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided.

CONCLUSION

This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.

The enigmatic role of TIPE2 in asthma

Unlike other members of the tumor necrosis factor (TNF)-α-induced protein 8 (TNFAIP8/TIPE) family that play a carcinogenic role and regulate apoptosis, TNFAIP8-like 2 (TIPE2) can not only maintain immune homeostasis but also regulate inflammation. TIPE2 mainly restrains the activation of T cell receptor (TCR) and Toll-like receptors (TLR), regulating its downstream signaling pathways, thereby regulating inflammation. Interestingly, TIPE2 is abnormally expressed in many inflammatory diseases and may promote or inhibit inflammation in different diseases. This review summarizes the molecular target and cellular function of TIPE2 in immune cells and inflammatory diseases and the underlying mechanism by which TIPE2 regulates inflammation. The function and mechanism of TIPE2 in asthma is also explained in detail. TIPE2 is abnormally expressed in asthma and participates in the pathogenesis of different phenotypes of asthma through regulating multiple inflammatory cells' activity and function. Considering the indispensable role of TIPE2 in asthma, TIPE2 may be an effective therapeutic target in asthma. However, the available data are insufficient to provide a full understanding of the complex role of TIPE2 in human asthma. Further study is still necessary to explore the possible mechanism and functions of TIPE2 in different asthma phenotypes.

Dual and Triple Epithelial Coculture Model Systems with Donor-Derived Microbiota and THP-1 Macrophages To Mimic Host-Microbe Interactions in the Human Sinonasal Cavities

Despite the relevance of the resident microbiota in sinonasal health and disease and the need for cross talk between immune and epithelial cells in the upper respiratory tract, these parameters have not been combined in a single in vitro model system. We have developed a coculture system of differentiated respiratory epithelium and natural nasal microbiota and incorporated an immune component. As indicated by absence of cytotoxicity and stable cytokine profiles and epithelial integrity, nasal microbiota from human origin appeared to be well tolerated by host cells, while microbial community composition remained representative for that of the human (sino)nasal cavity. Importantly, the introduction of macrophage-like cells enabled us to obtain a differential readout from the epithelial cells dependent on the donor microbial background to which the cells were exposed. We conclude that both model systems offer the means to investigate host-microbe interactions in the upper respiratory tract in a more representative way.

The epithelium of the human sinonasal cavities is colonized by a diverse microbial community, modulating epithelial development and immune priming and playing a role in respiratory disease. Here, we present a novel in vitro approach enabling a 3-day coculture of differentiated Calu-3 respiratory epithelial cells with a donor-derived bacterial community, a commensal species (Lactobacillus sakei), or a pathobiont (Staphylococcus aureus). We also assessed how the incorporation of macrophage-like cells could have a steering effect on both epithelial cells and the microbial community. Inoculation of donor-derived microbiota in our experimental setup did not pose cytotoxic stress on the epithelial cell layers, as demonstrated by unaltered cytokine and lactate dehydrogenase release compared to a sterile control. Epithelial integrity of the differentiated Calu-3 cells was maintained as well, with no differences in transepithelial electrical resistance observed between coculture with donor-derived microbiota and a sterile control. Transition of nasal microbiota from in vivo to in vitro conditions maintained phylogenetic richness, and yet a decrease in phylogenetic and phenotypic diversity was noted. Additional inclusion and coculture of THP-1-derived macrophages did not alter phylogenetic diversity, and yet donor-independent shifts toward higher Moraxella and Mycoplasma abundance were observed, while phenotypic diversity was also increased. Our results demonstrate that coculture of differentiated airway epithelial cells with a healthy donor-derived nasal community is a viable strategy to mimic host-microbe interactions in the human upper respiratory tract. Importantly, including an immune component allowed us to study host-microbe interactions in the upper respiratory tract more in depth.

IMPORTANCE Despite the relevance of the resident microbiota in sinonasal health and disease and the need for cross talk between immune and epithelial cells in the upper respiratory tract, these parameters have not been combined in a single in vitro model system. We have developed a coculture system of differentiated respiratory epithelium and natural nasal microbiota and incorporated an immune component. As indicated by absence of cytotoxicity and stable cytokine profiles and epithelial integrity, nasal microbiota from human origin appeared to be well tolerated by host cells, while microbial community composition remained representative for that of the human (sino)nasal cavity. Importantly, the introduction of macrophage-like cells enabled us to obtain a differential readout from the epithelial cells dependent on the donor microbial background to which the cells were exposed. We conclude that both model systems offer the means to investigate host-microbe interactions in the upper respiratory tract in a more representative way.

Anti-IL-13Rα2 therapy promotes recovery in a murine model of inflammatory bowel disease

There continues to be a major need for more effective inflammatory bowel disease (IBD) therapies. IL-13Rα2 is a decoy receptor that binds the cytokine IL-13 with high affinity and diminishes its STAT6-mediated effector functions. Previously, we found that IL-13Rα2 was necessary for IBD in mice deficient in the anti-inflammatory cytokine IL-10. Here, we tested for the first time a therapeutic antibody specifically targeting IL-13Rα2. We also used the antibody and Il13ra2^-/- mice to dissect the role of IL-13Rα2 in IBD pathogenesis and recovery. Il13ra2^-/- mice were modestly protected from induction of dextran sodium sulfate (DSS)-induced colitis. Following a 7-day recovery period, Il13ra2^-/- mice or wild-type mice administered the IL-13Rα2-neutralizing antibody had significantly improved colon health compared to control mice. Neutralizing IL-13Rα2 to increase IL-13 bioavailability promoted resolution of IBD even if neutralization occurred only during recovery. To link our observations in mice to a large human cohort, we conducted a phenome-wide association study of a more active variant of IL-13 (R130Q) that has reduced affinity for IL-13Rα2. Human subjects carrying R130Q reported a lower risk for Crohn's disease. Our findings endorse moving anti-IL-13Rα2 into preclinical drug development with the goal of accelerating recovery and maintaining remission in Crohn's disease patients.

TIPE2 inhibits GC via regulation of cell proliferation, apoptosis and inflammation

Gastric cancer (GC), a type of gastric mucosal epithelium disease caused by common malignant tumors, has become a major threat to human health and survival. Tumor necrosis factor-α-induced protein-8 like-2 (TIPE2) is a negative immune regulatory factor that is selectively expressed in immune organs, immune cells and various epithelial cells and serves an important role in the maintenance of human physiological immune homeostasis. In our preliminary study, we found that the expression of TIPE2 was downregulated or absent in GC tissues compared with normal gastric mucosa tissues, indicating that TIPE2 may play a significant role in the development of GC. To clarify the role of TIPE2 in the progression of human GC and to elucidate the underlying mechanism, the association between TIPE2 and phosphatidylinositol 3-kinase (PI3K)/AKT, the cell cycle, the caspase-related apoptosis pathway and the NF-κB signaling pathway were investigated through western blot and flow cytometric analysis. It was determined that TIPE2 inhibited GC cell proliferation mainly by reducing the expression of phosphorylated AKT and ERK, which caused subsequent inhibition of the PI3K-AKT and Ras-Raf-MEK-ERK1/2 signaling pathways. Additionally, we investigated the relationship between TIPE2 and GC and discovered that TIPE2 inhibited tumor progression via growth, apoptosis and inflammatory pathways. The results of the present study provided a theoretical basis for the development and application of TIPE2 as an antitumor agent.

Pathogenesis of Recalcitrant Chronic Rhinosinusitis: The Emerging Role of Innate Immune Cells

Chronic rhinosinusitis (CRS) is a major part of the recalcitrant inflammatory diseases of the upper airway that needs enormous socioeconomic burden. T helper (Th) 2 type immune responses recruiting eosinophils were the most well-known immune players in CRS pathogenesis especially in western countries. By the piling up of a vast amount of researches to elucidate the pathogenic mechanism of CRS recently, heterogeneous inflammatory processes were found to be related to the phenotypes of CRS. Recently more cells other than T cells were in the focus of CRS pathogenesis, such as the epithelial cell, macrophage, innate lymphoid cells, and neutrophils. Here, we reviewed the recent research focusing on the innate immune cells related to CRS pathogenesis.