Identification of novel targets for seasonal allergic rhinitis during and outside the pollen season by microarray analysis

The early-phase transcriptome and the clinical efficacy analysis in three modes of subcutaneous immunotherapy for allergic rhinitis

Background

Allergen immunotherapy is the only etiological treatment for allergic rhinitis.

Objective

To analyze the efficacy, safety, and mechanism of subcutaneous immunotherapy (SCIT).

Methods

The efficacy, safety, and serum immunological changes of 3 modes of subcutaneous immunotherapy were compared. Peripheral blood mononuclear cells (PBMC) transcriptome changes were obtained on the Illumina sequencing platforms. We confirmed differentially expressed genes (DEGs) by quantitative real-time polymerase chain reaction (PCR). The DEGs were analyzed by gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-protein interaction (PPI) networks. The correlation between the common DEGs and clinical indicators was analyzed by Origin 2022.

Results

The 3 SCITs were all effective after 1 year. The Combined Symptom and Medication Score (CSMS) and Visual Analog Score (VAS) in rush immunotherapy (RIT) are lowest after 24 and 48 weeks of treatment among the 3 groups. After treatment, the levels of sIgE, sIgE/tIgE, Th2 cytokines, Th17 cytokines, and percentage of peripheral eosinophils (EOS%) decreased significantly (P＜0.05), while the levels of Th1 type cytokines did not change significantly. Transcriptome analysis identified 24, 24, and 91 DEGs at W3 and 42, 52, 175 DEGs at W7 in conventional immunotherapy (CIT), cluster immunotherapy (CLIT), and RIT groups, respectively. The pathways and functions involved in SCIT include secretion of Th1/2 cytokines, immune cell differentiation. Unlike CIT and CLIT, DEGs are also involved in T cell tolerance induction, T cell anergy, and lymphocyte anergy in RIT. CXCR1, CXCR2, and IER3 had a specific effect on reflecting the improvement of symptoms in allergic rhinitis patients with SCIT.

Conclusion

The clinical efficacy of RIT appeared earlier than CIT and CLIT. Clinicians can use the highly conserved gene expression profile to evaluate responses to immunotherapy.

Mechanism of Kruppel-Like Factor 4 in Pyroptosis of Nasal Mucosal Epithelial Cells in Mice With Allergic Rhinitis

BACKGROUND

Allergic rhinitis (AR) is a chronic nasal inflammation, characterized by nasal epithelial dysfunction. Gene therapy targeting transcription factors is a promising strategy for quenching allergic inflammation, including AR.

OBJECTIVE

This study sought to probe the mechanism of Kruppel-like factor 4 (KLF4) in pyroptosis of nasal mucosal epithelial cells (NEpCs) in AR mice and provide targets for AR treatment.

METHODS

AR mouse models were established using sensitization with ovalbumin, followed by injection with short hairpin RNA KLF4 (sh-KLF4). AR symptoms were assessed by the times of sneezing and nose rubbing, hematoxylin-eosin, and periodic acid-Schiff staining. Levels of KLF4, nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3), cleaved caspase-1, and N-terminal domain (GSDMD-N) in nasal mucosal tissues were determined by Western blot assay, and levels of interleukin (IL)-1β and IL-18 in nasal lavage fluid were determined by enzyme-linked immunosorbent assay. The binding of KLF4 to the NLRP3 promoter was verified using chromatin immunoprecipitation and dual-luciferase assays. The functional rescue experiment was performed with oe-NLRP3 and sh-KLF4 in AR mice.

RESULTS

KLF4 was upregulated in nasal mucosal tissues of AR mice. KLF4 inhibition reduced the times of sneezing and nose rubbing, inflammatory cell infiltration, and goblet cell hyperplasia in nasal mucosal tissues, and levels of NLRP3, cleaved caspase-1, GSDMD-N, IL-1β, and IL-18. KLF4 was enriched on the NLRP3 promoter and improved NLRP3 expression. NLRP3 overexpression reversed the inhibition of sh-KLF4 on pyroptosis of NEpCs in AR mice.

CONCLUSION

KLF4 bound to the NLRP3 promoter and promoted pyroptosis of NEpCs in AR mice via activating NLRP3.

MicroRNA-29a promotes the proliferation of human nasal epithelial cells and inhibits their apoptosis and promotes the development of allergic rhinitis by down-regulating FOS expression

OBJECTIVE

To explore the regulation of microRNA-29a (miR-29a) on FOS in human nasal epithelial cells and its molecular mechanism, as well as the effects of miR-29a on the cell proliferation and apoptosis.

METHODS

By cell transfection, gene silencing, quantitative real-time polymerase chain reaction (qRT-PCR), flow cytometry and TUNEL assay (for cell apoptosis), CCK-8 assay (for cell proliferation), dual-luciferase reporter gene assay and Western Blot, it was validated that miR-29a promoted the proliferation of human nasal epithelial cells and inhibited their apoptosis by down-regulating FOS expression in RPMI2650 and HNEpC cell lines.

RESULTS

①Compared with healthy controls, miR-29a expression was up-regulated and FOS mRNA expression was down-regulated in the nasal tissues from the patients with allergic rhinitis (AR). ②MiR-29a over-expression promoted the proliferation of RPMI2650 cells and HNEpC cells but inhibited their apoptosis. ③MiR-29a targeted at FOS. ④MiR-29a over-expression and FOS silencing both significantly promoted cell proliferation and inhibited cell apoptosis. After transfection with both miR-29a and FOS, there was a decrease in the proliferation but an increase in the apoptosis of cells.⑤MiR-29a promoted the proliferation of human nasal epithelial cells and inhibited their apoptosis by down-regulating FOS expression.

CONCLUSION

MiR-29a-/FOS axis can be regarded as a potential marker and a new therapy for AR.

circARRDC3 contributes to interleukin‑13‑induced inflammatory cytokine and mucus production in nasal epithelial cells via the miR‑375/KLF4 axis

Allergic rhinitis (AR) is a common inflammatory disorder of the nasal mucosa. It is a major risk factor for asthma development, and uncontrolled AR can lead to the worsening of asthma symptoms, which affects the quality of life and productivity of patients. Circular RNAs (circRNA) were reported to be involved in the pathogenesis of AR. The aim of the present study was to investigate the functional role of circRNA arrestin domain-containing 3 (circARRDC3) in AR progression. circARRDC3 knockdown suppressed the levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) and eotaxin and mucin 5AC (MUC5AC) in IL-13-induced nasal epithelial cells. Moreover, circARRDC3 silencing promoted viability and suppressed apoptosis in IL-13-induced NECs. circARRDC3 targeted microRNA (miR)-375 and negatively regulated its expression. miR-375 inhibition reversed the effects of circARRDC3 knockdown on GM-CSF, eotaxin and MUC5AC expression levels, cell viability and cell apoptosis. In addition, miR-375 inhibited krueppel-like factor 4 (KLF4) expression through direct interaction, and miR-375 overexpression inhibited GM-CSF, eotaxin and MUC5AC expression levels, and cell apoptosis, which was abolished following KLF4 overexpression. In addition, circARRDC3, miR-375 and KLF4 were all dysregulated in the nasal mucosa of patients with AR. miR-375 expression was negatively correlated with circARRDC3 and KLF4 expression, and circARRDC3 expression was positively correlated with KLF4 expression. In conclusion, circARRDC3 contributed to the development of AR by regulating the miR-375/KLF4 axis. These findings may provide novel insights into the pathogenesis of AR.

Long Non-Coding RNA (lncRNA) Small Nucleolar RNA Host Gene 15 (SNHG15) Alleviates Osteoarthritis Progression by Regulation of Extracellular Matrix Homeostasis

BACKGROUND Growing evidence suggests that long non-coding RNAs (lncRNAs), as decoys of microRNAs (miRNAs), are involved in osteoarthritis (OA) progression, but the potential mechanism of lncRNA SNHG15 in OA remains unknown. Thus, the present study explored the molecular mechanism of SNHG15 in OA progression. MATERIAL AND METHODS OA chondrocytes were created by 20 ng/ml IL-1ß stimulation, and the experimental OA model was created by destabilization of the medial meniscus (DMM) surgery. Cartilage histomorphology was observed by safranin and fast green double dyeing. The relationships between SNHG15 and miR-7, KLF4, and miR-7 were determined by dual-luciferase assay or RNA immunoprecipitation (RIP). Immunofluorescence was used to detect the expressions of Ki67, collagen II, and Aggrecan. Moreover, SNHG15, miR-7, KLF4, MMP3, ADAMTS5, COL2A1, Aggrecan, and ß-catenin expressions were assessed by qRT-PCR or Western blot. The methylation status of SNHG15 promoter was evaluated by MS-PCR. RESULTS Underexpression of KLF4 and SHNG15 and overexpression of miR-7 were found in human OA knee cartilage tissues and IL-1ß-stimulated OA chondrocytes. SHNG15 overexpression significantly inhibited ECM degradation and promoted chondrocyte formation of OA chondrocytes. Furthermore, SNHG15 regulated KLF4 expression by sponging miR-7. Further analysis found that SNHG15 significantly inhibited b-catenin in OA chondrocytes. SNHG15 had a higher level of methylation in human OA tissues than in normal cartilage tissues. CONCLUSIONS Our results revealed that SNHG15 alleviated OA progression by regulating ECM homeostasis, which provides a promising target for OA therapy.

Identification of Susceptibility Genes to Allergic Rhinitis by Gene Expression Data Sets

As an extremely prevalent disease worldwide, allergic rhinitis (AR) is a condition characterized by chronic inflammation of the nasal mucosa. To identify the finer molecular mechanisms associated with the AR susceptibility genes, differentially expressed genes (DEGs) in AR were investigated. The DEG expression and clinical data of the GSE19187 data set were used for weighted gene co‐expression network analysis (WGCNA). After the modules related to AR had been screened, the genes in the module were extracted for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, whereby the genes enriched in the KEGG pathway were regarded as the pathway‐genes. The DEGs in patients with AR were subsequently screened out from GSE19187, and the sensitive genes were identified in GSE18574 in connection with the allergen challenge. Two kinds of genes were compared with the pathway‐genes in order to screen the AR susceptibility genes. Receiver operating characteristic (ROC) curve was plotted to evaluate the capability of the susceptibility genes to distinguish the AR state. Based on the WGCNA in the GSE19187 data set, 10 co‐expression network modules were identified. The correlation analyses revealed that the yellow module was positively correlated with the disease state of AR. A total of 89 genes were found to be involved in the enrichment of the yellow module pathway. Four genes (CST1,SH2D1B,DPP4, and SLC5A5) were upregulated in AR and sensitive to allergen challenge, whose potentials were further confirmed by ROC curve. Taken together, CST1,SH2D1B,DPP4, and SLC5A5 are susceptibility genes to AR.

The Role of KLF4 in Alzheimer's Disease

Krüppel-like factor 4 (KLF₄), a member of the family of zinc-finger transcription factors, is widely expressed in range of tissues that play multiple functions. Emerging evidence suggest KLF₄’s critical regulatory effect on the neurophysiological and neuropathological processes of Alzheimer’s disease (AD), indicating that KLF₄ might be a potential therapeutic target of neurodegenerative diseases. In this review, we will summarize relevant studies and illuminate the regulatory role of KLF₄ in the neuroinflammation, neuronal apoptosis, axon regeneration and iron accumulation to clarify KLF₄’s status in the pathogenesis of AD.