Mice with double knockout of H2-Eb1 and H2-Ab1 exhibit reduced susceptibility to allergic rhinitis

Investigation into the role of H2-Ab1 in vascular remodeling in pulmonary arterial hypertension via Bioinformatics

BACKGROUND

Pulmonary arterial hypertension (PAH) is a progressive disease of vascular remodeling characterized by persistent pulmonary arterial pressure elevation, which can lead to right heart failure and premature death. Given the complex pathogenesis and poor prognosis of PAH, the identification and investigation of biomarkers become increasingly critical for advancing further understanding of the disease.

METHODS

PAH-related datasets, GSE49114, GSE180169 and GSE154959, were downloaded from the publicly available GEO database. By performing WGCNA on the GSE49114 dataset, a total of 906 PAH-related key module genes were screened out. By carrying out differential analysis on the GSE180169 dataset, a total of 576 differentially expressed genes were identified. Additionally, the GSE154959 single-cell sequencing dataset was also subjected to differential analysis, leading to the identification of 34 DEGs within endothelial cells. By taking intersection of the above three groups of DEGs, five PAH-related hub genes were screened out, namely Plvap, Cyp4b1, Foxf1, H2-Ab1, and H2-Eb1, among which H2-Ab1 was selected for subsequent experiments.

RESULTS

A SuHx mouse model was prepared using the SU5416/hypoxia method, and the successful construction of the model was evaluated through Hematoxylin-Eosin staining, hemodynamic detection, fulton index, and Western Blot (WB). The results of WB and qRT-PCR demonstrated a significant upregulation of H2-Ab1 expression in SuHx mice. Consistent with the results of bioinformatics analysis, a time-dependent increase was observed in H2-Ab1 expression in hypoxia-treated mouse pulmonary artery endothelial cells (PAECs). To investigate whether H2-Ab1 affects the development and progression of PAH, we knocked down H2-Ab1 expression in PAECs, and found that its knockdown inhibited the viability, adhesion, migration, and angiogenesis, while concurrently promoted the apoptosis of PAECs.

CONCLUSION

H2-Ab1 could regulate the proliferation, apoptosis, adhesion, migration, and angiogenesis of PAECs.

Therapeutic Effects of Human Pluripotent Stem Cell-Derived Mesenchymal Stem Cells on a Murine Model of Acute Type-2-Dominated Airway Inflammation

Allergic rhinitis and allergic asthma are the most common type-2 inflammatory diseases, which are hardly curable and cause heavy burden to general well-being. Mesenchymal stem cells (MSCs) are multipotent nonhematopoietic cells with potential immunomodulatory effects that have been showning to have a therapeutic effect on allergic diseases. Here, we investigated the effects of human induced pluripotent stem cell (iPSC)-derived MSCs on airway hyperresponsiveness and acute type-2-dominated inflammation throughout the upper and lower airways. In this study, human MSCs, MSC cell culture supernatant, and culture medium (control) was injected into the acute airway inflammatory model via the tail vein. Mouse behavioristics were recorded immediately and mouse lung function was measured 24 hours after the last ovalbumin (OVA) challenge. Histological staining, Luminex, Elisa and flow cytometry were employed to evaluate the effects on the production of total/OVA-specific IgG1 and IgE, cytokines expression in lung tissues, and inflammatory cells infiltration in the lung and spleen of the experimental mice. Expressions of eotaxin, IL-4, IL-5, IL-13, IL-33 in nasal and lung lavage were evaluated by Luminex and Elisa. We found that for this acute inflammatory mouse model, human MSC transplantation significantly mitigated the decreased motoring time and the increased lung function Rrs caused by OVA challenge. Serum OVA-IgG1, OVA-IgE, and eosinophil percentages in the splenocytes were significantly decreased. Injection of the MSC supernatant also showed the same trend, but not significantly changed. After treatment, IL-4 and IL-13 were significantly decreased in the lung tissue, and IL-5 and IL-13 were significantly decreased in lung lavage. In conclusion, both human MSC culture supernatant and cell transplantation could alleviate AHR and inflammation in acute inflammatory experimental animals, which demonstrated their potential for clinical therapeutics. Human iPSC-MSCs, MSC cell culture supernatant, or culture medium (control) was injected into the OVA-induced acute airway inflammatory model via the tail vein. Behavioral changes, AHR, serum OVA-specific IgG1 and IgE concentrations, and type-2 inflammations were alleviated.

Period2 gene regulates diurnal changes of nasal symptoms in an allergic rhinitis mouse model

Background

Allergic rhinitis (AR) symptoms exhibit prominent 24‐hour variations associated with the biological clock. Although endogenous glucocorticoids synchronize circadian oscillator in the nasal mucosa, the precise mechanism of AR remains unclear. Therefore, using a mouse model, we investigated the association between circadian‐clock genes and AR symptoms at various time‐points.

Methods

Based on the rhythmic secretion of corticosterone levels, we chose 2 time‐points, ZT4 (10:00 AM) and ZT16 (10:00 PM), to observe dynamic changes of nasal symptoms, immunologic responses, and circadian‐clock gene period (Per) expressions.

Results

In the AR group, nasal symptom scores at ZT4 were significantly higher than at ZT16, with a greater increase in eosinophils, mast cells, and total immunoglobulin E levels at ZT4. The scores had a negative correlation with fluctuation of corticosterone levels. T‐helper 1 (Th1) cell counts and interferon‐γ levels decreased significantly at ZT4 compared with ZT16 in the AR group, whereas Th2 cells; Th17 cells; and interleukin (IL)‐4, ‐13, and ‐17A levels increased significantly at ZT4 compared with ZT16. Furthermore, Per2 gene expression levels were attenuated at ZT4 and elevated at ZT16, but correlated negatively with Th2 and Th17 responses associated with Gata3 and Rorγt expression levels that were enhanced at ZT4 and reduced at ZT16 in the AR group.

Conclusion

Our results suggest that the Per2 gene may influence diurnal variations of AR symptom severity, partially through its possible anti‐inflammatory effect on the circadian regulation of GATA3 and RORγt levels in immune cells. This further demonstrates the neural‐immune‐endocrinal mechanism of circadian rhythm in AR and sheds new light on chronotherapeutic approaches to AR.