ILC2 influence the differentiation of alveolar type II epithelial cells in bronchopulmonary dysplasia mice.

Bronchopulmonary dysplasia, a common complication of premature infants, is mainly characterized by blocked alveolarization. Proverbially, the injury of alveolar type II epithelial cells is regarded as the pathologic basis of occurrence and development of bronchopulmonary dysplasia. In the case of alveolar epithelial damage, alveolar type II epithelial cells can also differentiate to alveolar type I epithelial cells as progenitor cells. During bronchopulmonary dysplasia, the differentiation of alveolar type II epithelial cells becomes abnormal. Group 2 innate lymphoid cells can produce type 2 cytokines in response to a variety of stimuli, including the epithelial cytokines IL-25, IL-33, and thymic stromal lymphopoietin. Previous studies have shown that group 2 innate lymphoid cells can inhibit the alveolarization process of bronchopulmonary dysplasia by secreting IL-13. However, whether group 2 innate lymphoid cells can affect the differentiation of alveolar type II epithelial cells in the pathologic process of bronchopulmonary dysplasia remains unclear. In this study, we have shown that IL-13 secreted by group 2 innate lymphoid cells increased during bronchopulmonary dysplasia, which was related to the release of large amounts of IL-33 by impaired alveolar type II epithelial cells. This led to abnormal differentiation of alveolar type II epithelial cells, reduced differentiation to alveolar type I epithelial cells, and increased transdifferentiation to mesenchymal cells through the epithelial-mesenchymal transition. Taken together, our study provides a complementary understanding of the development of bronchopulmonary dysplasia and highlights a novel immune mechanism in the pathogenesis of bronchopulmonary dysplasia.

Type 2 innate lymphoid cell-derived amphiregulin regulates type II alveolar epithelial cell transdifferentiation in a mouse model of bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) is a common complication in preterm infants characterized by alveolar growth arrest. Interleukin (IL)-33 and type 2 innate lymphoid cell (ILC2) affect type II alveolar epithelial cell (AECII) differentiation in BPD mice and may cause increased lung epithelial-mesenchymal transition (EMT). Amphiregulin (AREG) can be produced by ILC2 and is associated with tissue repair. However, the action mechanism of AREG produced by ILC2 to alveolar development in BPD is unclear. In this study, we aimed to demonstrate the role and mechanism of AREG in influencing AECII transdifferentiation in the lung tissue of BPD mice. The effects of ILC2-derived AREG on AECII transdifferentiation were verified in vivo and in vitro, and the role of IL-33 on ILC2-derived AREG in AECII transdifferentiation in BPD mice and a preliminary investigation of the role of AREG's receptor-epidermal growth factor receptor (EGFR) on AECII transdifferentiation. The results showed that neonatal mice developed severe lung injury after hyperoxia, and IL-33 induced AREG production via ILC2 affected normal AECII differentiation and promoted EMT. In addition, the blockade of EGFR was found to alleviate the impaired AECII differentiation under hyperoxia in an in vitro study. In summary, our study demonstrates that AREG secreted by ILC2 affects AECII transdifferentiation in BPD mice, which provides a new idea for the clinical treatment of BPD.

ILC2 regulates hyperoxia-induced lung injury via an enhanced Th17 cell response in the BPD mouse model.

BACKGROUD: Recent research has focused on the role of immune cells and immune responses in the pathogenesis of bronchopulmonary dysplasia (BPD), but the exact mechanisms have not yet been elucidated. Previously, the key roles of type 2 innate lymphoid cells (ILC2) in the lung immune network of BPD were explored. Here, we investigated the role Th17 cell response in hyperoxia-induced lung injury of BPD, as well as the relationship between ILC2 and Th17 cell response. METHODS: A hyperoxia-induced BPD mouse model was constructed and the pathologic changes of lung tissues were evaluated by Hematoxylin-Eosin staining. Flow cytometry analysis was conducted to determine the levels of Th17 cell, ILC2 and IL-6+ILC2. The expression levels of IL-6, IL-17 A, IL-17 F, and IL-22 in the blood serum and lung tissues of BPD mice were measured by ELISA. To further confirm the relationship between ILC2 and Th17 cell differentiation, ILC2 depletion was performed in BPD mice. Furthermore, we used immunomagnetic beads to enrich ILC2 and then flow-sorted mouse lung CD45+Lin-CD90.2+Sca-1+ILC2. The sorted ILC2s were injected into BPD mice via tail vein. Following ILC2 adoptive transfusion, the changes of Th17 cell response and lung injury were detected in BPD mice. RESULTS: The expression levels of Th17 cells and Th17 cell-related cytokines, including IL-17 A, IL-17 F, and IL-22, were significantly increased in BPD mice. Concurrently, there was a significant increase in the amount of ILC2 and IL-6+ILC2 during hyperoxia-induced lung injury, which was consistent with the trend for Th17 cell response. Compared to the control BPD group, ILC2 depletion was found to partially abolish the Th17 cell response and had protective effects against lung injury after hyperoxia. Furthermore, the adoptive transfer of ILC2 enhanced the Th17 cell response and aggravated lung injury in BPD mice. CONCLUSIONS: This study found that ILC2 regulates hyperoxia-induced lung injury by targeting the Th17 cell response in BPD, which shows a novel strategy for BPD immunotherapy.

Clinical features and risk factors of lung cancer in elderly patients with dermatomyositis.

BACKGROUND: Although there are concerns about the association between dermatomyositis (DM) and malignancy, the clinical features in elderly DM patients with lung cancer are largely unknown. Here, we elucidated the clinical features and risk factors of lung cancer in elderly DM patients. METHODS: The data of elderly DM patients (≥65 years old) with or without lung cancer admitted to the Second Xiangya Hospital, Central South University from January 2016 to November 2022 were retrospectively analyzed. RESULTS: Male patients with elderly onset DM (EODM) symptoms were found to be prone to lung cancer (p < 0.001). Elderly DM patients with lung cancer had a higher ratio of a history of smoking and were more likely to present with heliotrope rash, V sign and dysphasia and elevated monocyte-to-lymphocyte ratio (MLR) and there was a higher ratio of anti-TIF1-γ-Ab-positive patients (all p < 0.05). Occurrence of interstitial lung disease (ILD), elevated aspartate aminotransferase (AST) and anti-aminoacyl-tRNA synthetase (anti-ARS)-antibody positive rates were less common in elderly DM patients with lung cancer than those without lung cancer (all p < 0.05). Multivariate logistic regression analysis showed smoking history (p = 0.011, OR = 4.532), elevated MLR (p = 0.018, OR = 1.159) and anti-TIF1-γ-Ab-positive status (p = 0.034, OR = 8.529) were independently associated with the presence of lung cancer, while ILD might be a protective factor (p = 0.024, OR = 0.179) for lung cancer in elderly patients with DM. CONCLUSIONS: Lung cancer is more common in male patients with EODM symptoms. Smoking, elevated MLR and being anti-TIF1-γ-Ab-positive were associated with higher frequencies of lung cancer in elderly DM patients. It is necessary to screen lung cancer in elderly DM patients with a history of smoking, elevated MLR or being anti-TIF1-γ-Ab-positive.

IL-33-ST2 pathway regulates AECII transdifferentiation by targeting alveolar macrophage in a bronchopulmonary dysplasia mouse model.

Evidence points to the indispensable function of alveolar macrophages (AMs) in normal lung development and tissue homeostasis. However, the importance of AMs in bronchopulmonary dysplasia (BPD) has not been elucidated. Here, we identified a significant role of abnormal AM proliferation and polarization in alveolar dysplasia during BPD, which is closely related to the activation of the IL-33-ST2 pathway. Compared with the control BPD group, AMs depletion partially abolished the epithelialmesenchymal transition process of AECII and alleviated pulmonary differentiation arrest. In addition, IL-33 or ST2 knockdown has protective effects against lung injury after hyperoxia, which is associated with reduced AM polarization and proliferation. The protective effect disappeared following reconstitution of AMs in injured IL-33 knockdown mice, and the differentiation of lung epithelium was blocked again. In conclusion, the IL-33-ST2 pathway regulates AECII transdifferentiation by targeting AMs proliferation and polarization in BPD, which shows a novel strategy for manipulating the IL-33-ST2-AMs axis for the diagnosis and intervention of BPD.

Effect of miR-124a on collagen-induced arthritis in mice and the underlying mechanisms. / MiR-124aå¯¹èƒ¶åŽŸè¯±å¯¼æ€§å ³èŠ‚ç‚Žå°é¼ çš„å½±å“åŠå ¶æœºåˆ¶.

OBJECTIVES: Rheumatoid arthritis (RA) is a chronic autoimmune disease. MicroRNA has been shown to play an important role in RA. MicroRNA-124a (miR-124a) has anti-proliferative and anti-inflammatory effects in RA fibroblast synovial cells. This study aims to explore the effects of miR-124a overexpression on arthritis in collagen-induced arthritis (CIA) mice and the underlying mechanisms. METHODS: Bovine type II collagen and complete Ferris adjuvant were used to induce CIA model from DBA/1 mice. Twenty-eight days after initial immunization (D28), CIA mice were randomly divided into a model group, a miR-124a treatment group, and a negative control (NC) group. Physiological saline, miR-124a agomir, and miR-124a agomir NC were injected into the skin at the tail root of mice every 3 days for 4 times, respectively. The degree of joint swelling and arthritis index of mice were recorded accordingly. Sixty-three days after initial immunization (D63), the mice were sacrificed to obtain the synovial tissue of ankle joint. HE staining was used to observe the proliferation of synovial cell, infiltration of inflammatory cell, pannus, and bone erosion of synovial tissues; TUNEL staining was used to detect cell apoptosis; qRT-PCR was used to detect the mRNA expression of miR-124a, phosphatidylinositol-3-kinase catalytic subunit alpha (PIK3CA) and its downstream genes Bcl-2 and Bax. Immunohistochemistry was used to detect the protein expression of PIK3CA, Bcl-2, and Bax protein in synovial tissues of each group. RESULTS: Different degrees of swelling presented in the paws of DBA/1 mice at D28, which indicated the CIA model was constructed successfully. Forty-eight days after initial immunization (D48), the paws of mice in the miR-124a treatment group were only slightly red and swollen, while the paws of mice in the model group and the NC group were obviously red and swollen. The arthritis index of mice in the miR-124a treatment group were decreased significantly compared to the NC group at D51, D53, D59, and D62 (51, 53, 59, 62 days after initial immunization) (all P<0.05). Sixty-three days after initial immunization (D63), HE staining indicated that the scores of synovial cell proliferation, inflammatory cell infiltration, synovial pannus, and bone erosion were significantly reduced in the miR-124a treatment group (P<0.05 or P<0.01), while cell apoptosis was increased in the miR-124a treatment group compared with the model group and NC group (P<0.01 or P<0.001). Besides, the expression of miR-124a and Bax in the synovial tissue in miR-124a treatment group was significantly higher than those in the model group and NC group (P<0.01 or P<0.001), while the expressions of PIK3CA and Bcl-2 were decreased (P<0.05 or P<0.01 or P<0.001), and the ratio of Bcl-2 to Bax was significantly decreased (P<0.01 or P<0.001). CONCLUSIONS: Overexpression of miR-124a can reduce arthritis in CIA mice bacause it could promote synovial cell apoptosis and inhibit synovial cell proliferation via targeting PIK3CA and regulating its downstream pathways.

Dynamic Changes of NCR- Type 3 Innate Lymphoid Cells and Their Role in Mice with Bronchopulmonary Dysplasia.

Inflammation is one of the important pathogenesis of bronchopulmonary dysplasia (BPD). Type 3 innate lymphoid cells (ILC3) play a role in a variety of inflammatory lung diseases. In this study, we established the BPD model by injecting lipopolysaccharide into the amniotic cavity of pregnant mice. Here, we investigated the dynamic changes of ILC3 and NKP46- ILC3 population in lung tissues of mice from BPD and the control groups. Results showed that the proportion of ILC3 and NKP46-ILC3 in the BPD group was higher than those of the control group. In addition, the cytokines interleukin-17 (IL-17) and interleukin-22 (IL-22) secreted by ILC3 in this model had also changed that their expression was significantly increased compared with that of the control group. Flow cytometry demonstrated that ILC3 were a rapid source of IL-17. In the anti-CD90 knockdown experiment, we confirmed the alleviation of BPD inflammation in the absence of ILC3. In addition, we injected mice with anti-IL-17 neutralizing antibody, and the results showed that IL-17 could aggravate BPD inflammation. Taken together, ILC3 may play a pro-inflammatory role in BPD by secreting IL-17.

Tissue-Resident Type 2 Innate Lymphoid Cells Arrest Alveolarization in Bronchopulmonary Dysplasia.

Bronchopulmonary dysplasia (BPD) is a severe complication of the respiratory system associated with preterm birth. Type 2 innate lymphoid cells (ILC2s) play a major role in tissue homeostasis, inflammation, and wound healing. However, the role in BPD remains unclear. The present study showed that ILC2s, interleukin-4 (IL-4), IL-13, and anti-inflammatory (M2) macrophages increased significantly in BPD mice as compared to the control mice. Administration with recombinant mouse IL-33 amplified the above phenomena and aggravated the alveolar structural disorder and functional injury in mice subjected to BPD, and the opposite was true with anti-ST2 antibody. In addition, the depletion of ILC2s in BPD mice with anti-CD90.2 antibody substantially abolished the destructive effect on BPD. In the treatment of BPD with dexamethasone, the number of ILC2s and M2 macrophages and levels of IL-4 and IL-13 decreased with remission as compared to the control group. This study identified a major destructive role of the ILC2s in BPD that could be attenuated as a therapeutic strategy.

[The number of ILC3 and their related cytokines IL-17 and IL-22 increase in lungs of mice with bronchopulmonary dysplasia].

Objective To investigate dynamic changes of type 3 innate lymphoid cells (ILC3) in lungs of mice with bronchopulmonary dysplasia (BPD). Methods Forty newborn C57BL/6 mice were randomized into air group and the hyperoxia group, 20 mice in each group. C57BL/6 newborn mice were delivered by caesarean section on the 19th day of pregnancy and exposed to 850 mL/L O2 for replication of the BPD model. Five mice in each group were sacrificed 1 day, 3, 7, 14 days after they were born for procurement of fresh lung tissues. HE staining was used to observe the pathological changes of lung tissues. ELISA was used to detect the protein content of downstream cytokines interleukin-17 (IL-17), IL-22 and granulocyte-macrophage colony stimulating factor (GM-CSF) in lung homogenate. Flow cytometry was used for measuring the proportion of ILC3 in lymphocytes as well as the proportions of IL-17+ ILC3 and IL-22+ ILC3 in the lung. Results The proportion of ILC3 in lung tissues reached the peak on the 7th day after birth. In contrast with the air group, the proportion of ILC3 in the hyperoxia group was significantly elevated at the same time points. The protein content of IL-17 and IL-22 in the hyperoxia group went up significantly in comparison with those in the air group at the same time points, while the GM-CSF content in the hyperoxia group showed no significant changes. The proportions of IL-17+ILC3 and IL-22+ILC3 in the hyperoxia group significantly increased as compared with those in the air group at the same time points. Conclusion The secretion of IL-17 and IL-22 derived from ILC3 is associated with BPD.

[Association of short-term efficacy for infliximab in rheumatoid arthritis with plasma concentration and anti-drug antibody].

OBJECTIVE: To investigate the correlation between peripheral concentration of infliximab (IFX) or anti-IFX antibody titers and short-term therapeutic effect of IFX in patients with active rheumatoid arthritis (RA).
 Methods: Twenty patients with active RA were treated with combination of methotrexate (MTX), leflunomide (LEF) with IFX, and the clinical and laboratory index and the side effects were recorded before and after IFX treatment. Twenty healthy subjects were chosen as a control group.
 Results: After 14-week treatment, patients were categorized into good, moderate or no responders according to EULAR remission criteria. There were no significant differences in peripheral IFX concentration, anti-IFX antibody titers and TNF-α levels among the 3 groups, and there were no significant correlations among ΔDAS28-CRP, peripheral IFX concentration, anti-IFX antibody titers and TNF-α levels.
 Conclusion: Peripheral IFX concentration, anti-IFX antibody titers and TNF-α levels can not be used as reliable predictive index for short-term effect of IFX in active RA.