LAT alleviates Th2/Treg imbalance in an OVA-induced allergic asthma mouse model through LAT-PLC-γ1 interaction

The Tyrosine Phosphatase Activity of PTPN22 Is Involved in T Cell Development via the Regulation of TCR Expression

The protein tyrosine phosphatase PTPN22 inhibits T cell activation by dephosphorylating some essential proteins in the T cell receptor (TCR)-mediated signaling pathway, such as the lymphocyte-specific protein tyrosine kinase (Lck), Src family tyrosine kinases Fyn, and the phosphorylation levels of Zeta-chain-associated protein kinase-70 (ZAP70). For the first time, we have successfully produced PTPN22 CS transgenic mice in which the tyrosine phosphatase activity of PTPN22 is suppressed. Notably, the number of thymocytes in the PTPN22 CS mice was significantly reduced, and the expression of cytokines in the spleen and lymph nodes was changed significantly. Furthermore, PTPN22 CS facilitated the positive and negative selection of developing thymocytes, increased the expression of the TCRαβ-CD3 complex on the thymus cell surface, and regulated their internalization and recycling. ZAP70, Lck, Phospholipase C gamma1(PLCγ1), and other proteins were observed to be reduced in PTPN22 CS mouse thymocytes. In summary, PTPN22 regulates TCR internalization and recycling via the modulation of the TCR signaling pathway and affects TCR expression on the T cell surface to regulate negative and positive selection. PTPN22 affected the development of the thymus, spleen, lymph nodes, and other peripheral immune organs in mice. Our study demonstrated that PTPN22 plays a crucial role in T cell development and provides a theoretical basis for immune system construction.

Inhibition of CREB promotes glucocorticoids action on airway inflammation in pediatric asthma by promoting ferroptosis of eosinophils

BACKGROUND

Pediatric asthma is a common chronic disease of childhood with airway inflammation. Cyclic adenosine monophosphate response element binding protein (CREB) plays a significant role in the transcription of proinflammatory genes, but its role in pediatric asthma has remained unclear. Herein, we investigated the functions of CREB in pediatric asthma.

METHODS

Eosinophils were purified from the peripheral blood of interleukin 5 (IL5) transgenic (IL5T) neonatal mice. The contents of CREB, long-chain fatty-acid-CoA ligase 4, transferrin receptor protein 1, ferritin heavy chain 1, and glutathione peroxidase 4 in eosinophils were examined by Western blot analysis. The viability of eosinophils, and the mean fluorescence intensity of Siglec F, C-C motif chemokine receptor 3 (CCR3), and reactive oxygen species were examined by flow cytometry. The concentration of iron in eosinophils was assessed by a commercial kit. The contents of malondialdehyde, glutathione, glutathione peroxidase, IL-5, and IL-4 were discovered by enzyme-linked-immunosorbent serologic assay. The C57BL/6 mice were randomly divided into four groups: sham, ovalbumin (OVA), OVA+Ad-shNC, and OVA+Ad-shCREB. The bronchial and alveolar structures were evaluated by hematoxylin and eosin staining. Leukocytes and eosinophils in the blood were measured using a HEMAVET 950.

RESULTS

The abundance of CREB in eosinophils was enhanced by CREB overexpression vector transfection, but reduced by short hairpin (sh)CREB transfection. Downregulation of CREB triggered the cell death of eosinophils. Knockdown of CREB could obviously contribute to ferroptosis of eosinophils. In addition, downregulation of CREB facilitated dexamethasone (DXMS, a type of glucocorticoid)-induced eosinophils death. Moreover, we established an asthma mouse model by OVA treatment. The CREB was upregulated in OVA group mice, but Ad-shCREB treatment obviously downregulated CREB level. Downregulation of CREB diminished OVA-induced asthmatic airway inflammation by reducing the number of inflammatory cells and the levels of proinflammatory factors. Downregulated CREB enhanced the anti-inflammatory effect of DXMS in OVA-induced mice.

CONCLUSION

Inhibition of CREB promoted the effect of glucocorticoids on airway inflammation in pediatric asthma through promoting ferroptosis of eosinophils.

Research Progress of Hydrogen on Chronic Nasal Inflammation

Chronic nasal mucosal inflammatory disease is a common nasal disease, which is involved by inflammatory cells and a variety of cytokines. Its main pathological features are inflammatory reaction, increased secretion, mucosal swelling and thickening of nasal cavity or paranasal sinuses.It mainly includes chronic rhinitis (divided into allergic rhinitis, non-allergic rhinitis), chronic sinusitis (divided into with nasal polyps, without nasal polyps type), etc.The main symptoms of chronic rhinitis are nasal itching, sneezing, runny nose, and nasal congestion. The main symptoms of chronic sinusitis are nasal congestion, purulent or sticky nasal discharge, headache, and reduced sense of smell. They are a type of disease with a high incidence rate and seriously affect the quality of human life.Although the etiology and treatment of this type of disease have been extensively studied, there are still many aspects that are unclear.Currently, oxidative stress is believed to be an important link in the pathogenesis of chronic inflammatory diseases of the nasal mucosa. Therefore, anti-oxidative stress is a direction of research for the treatment of chronic nasal mucosal inflammatory diseases.Hydrogen, as a medically therapeutic gas, has been extensively studied for its antioxidant, anti-inflammatory, and anti-damage properties, and has been used in the treatment of various diseases.Although there are relatively few studies on the use of hydrogen for nasal inflammation, its positive effects have also been found. This article systematically summarizes the relevant research on the use of hydrogen to improve chronic nasal mucosal inflammation, with the aim of clarifying the ideas and indicating the direction for further research in the future.

Wuhu Decoction Regulates Dendritic Cell Autophagy in the Treatment of Respiratory Syncytial Virus (RSV)-Induced Mouse Asthma by AMPK/ULK1 Signaling Pathway

BACKGROUND Dendritic cell autophagy plays a pivotal role in asthma. Wuhu decoction can significantly improve respiratory syncytial virus (RSV) bronchiolitis and delay its development into asthma. The aim of the present study was to explore the therapeutic effect and mechanism of Wuhu decoction on RSV -induced asthma in mice. MATERIAL AND METHODS Establishment of asthmatic mice model was induced by RSV. Hematoxylin-eosin staining, periodic acid-Schiff (PAS) staining, and Masson trichrome staining were performed to observe pathological changes in the lungs. The levels of CD4⁺ T, CD8⁺ T, and CD4⁺ CD25⁺ T in blood were analyzed by flow cytometry. The contents of interleukin (IL)-4, interferon-gamma (IFN-γ), IL-10, and IL-13 in serum were measured by enzyme-linked immunosorbent assay (ELISA). The number of autophagosomes in dendritic cells (DCs) of lung tissue was observed by transmission electron microscope. The DCs of lung tissue were isolated by magnetic bead sorting. The levels of LC3-II, Beclin-1, and LC3-I in DCs and MMP-9, TIMP-1, AMPK, p-AMPK, ULK1, and LK1 expression in lung tissues were detected by western blot. Real-time polymerase chain reaction (PCR) detected the expression of AMPK and ULK1 genes. RESULTS Wuhu decoction can effectively alleviate chronic airway inflammation and airway remodeling and reduce airway hyperresponsiveness. Moreover, Wuhu decoction can significantly enhance the level of autophagy in DCs of lung tissue and promote the expression of AMPK and ULK1 in lung tissue. CONCLUSIONS Wuhu decoction may improve the RSV-induced asthmatic symptoms by enhancing autophagy of DCs in lung tissue dependent on the AMPK/ULK1 signaling pathway.

Analysis of lncRNA Expression in Patients With Eosinophilic and Neutrophilic Asthma Focusing on LNC_000127

Long non-coding RNA (lncRNA) is important in many diseases. Some studies have shown that lncRNA affects the pathogenesis of systemic inflammation of asthma. lncRNA regulates gene transcription, protein expression, and epigenetic regulation. However, lncRNAs associated with different airway phenotypes, such as eosinophilic (Eos) and neutrophilic (Neu) asthma have not been identified. The goal of this study was to determine the differences in circulating lncRNA signatures in Eos and Neu samples. Using RNA-sequencing (RNA-seq), lncRNA expression was evaluated in peripheral whole blood samples among Eos patients, Neu patients, and healthy individuals (Control). Bioinformatic analysis was used to predict relevant biological pathways. Quantitative PCR (qPCR) was used to measure gene expression in whole blood samples, Jurkat cells, and human CD4⁺ T cells. Finally, a novel lncRNA, LNC_000127, was inhibited by transfection of Jurkat cells with a lentiviral vector, and the effect was examined by Human Asthma RT² Profiler™ PCR Array and western blotting. Compared to control samples, Eos samples contained 190 unique lncRNAs and Neu samples had 166 unique lncRNAs (difference ≥2-fold). KEGG pathway annotation data and GO terms revealed that different lncRNAs are involved in different mechanisms. LNC_000127, was highly expressed in Eos samples before treatment; its expression was increased in Jurkat cells and human CD4⁺ T cells following stimulation with PMA/CD₂₈. Subsequent analyses revealed that LNC_000127 functions in the Th₂ inflammation pathway. The results suggest that lncRNAs are involved in different phenotypes of asthma. Whether the different phenotypes of asthma can be recognized based on these lncRNAs (as biomarkers) requires further analysis. Targeting LNC_000127 may be effective for reducing Th2 inflammation in Eos asthma.