View clinical trials related to Neutrophils.
Filter by:The purpose of this study is to determine whether a novel subset of neutrophils is correlated with corneal neovascularization in the patients suffered from ocular chemical injury.
Literature basis Acute respiratory distress syndrome (ARDS) is a clinical syndrome characterized by respiratory distress and progressive hypoxemia, which is caused by diffuse alveolar and pulmonary interstitial edema caused by various pulmonary and extrapulmonary factors other than cardiogenic factors. ARDS incidence rate is as high as 75 /10 000 per year, and sepsis and pulmonary infection are the most common causes. In the past, it was generally believed that excessive immune activation is the core of the pathophysiology of ARDS, and neutrophils are recognized as the core driver of inflammatory hyperactivity and lung injury in ARDS. Although some progress has been made in the epidemiology, pathogenesis and pathophysiology of ARDS in the past 50 years, and the clinical outcomes of some patients with ARDS have been improved by optimizing the mode of mechanical ventilation and fluid treatment, as well as prone ventilation and the use of muscle relaxants, ARDS is still one of the most common causes of death and disability in intensive care units, The mortality rate of the disease is currently as high as 30-40%. There is still a lack of effective drugs for the treatment of ARDS in clinic, and even glucocorticoids applied for immune overactivation have not achieved good results. This is related to the unclear pathogenesis of ARDS. Therefore, it is still a hot and difficult point to further explore the pathogenesis and progression of ARDS and find new therapeutic targets. In the past, mature PMN in peripheral blood was generally considered as a functional cell in the end stage, but it is widely involved in different innate immune responses (including inflammation, infection, tumor, autoimmunity, etc.) and can adopt very different effector mechanisms. Therefore, with the deepening of research, neutrophil subtypes with different functions (such as immune regulation and repair) have been identified in recent years: cd16dimcd62lbrightpmn and cd16brightcd62ldimmpmn. In the steady state of healthy people, the classic mature neutrophils (cd16brightcd62lbright) in peripheral blood account for more than 98% of the total PMN, and the proportion of the two neutrophil subtypes is relatively low. In the inflammatory state, the proportion of cd16dimcd62lbright and cd16brightcd62ldim neutrophils increased significantly. Proteomic analysis showed that there were significant differences between the two subtypes of neutrophils. The nucleus of cd16dimcd62lbright neutrophil subgroup is banded, which is released from bone marrow after being stimulated by lipopolysaccharide (LPS). It accounts for 20% - 25% of PMN in whole blood in LPS infection model. The apoptosis rate is significantly reduced, and the bacteriostatic effects such as oxidative burst and phagocytosis are significantly enhanced; On the contrary, cd16brightcd62ldim neutrophil subgroup has reduced antibacterial ability and shows immunosuppressive phenotype. It is a newly discovered neutrophil subtype with immunosuppressive function in recent years, which can inhibit T cell proliferation, which is related to immunosuppression in the experimental human endotoxemia model. In our previous studies, we have successfully obtained a new amino acid derivative of ocotillol ginsenoside, which may have the pharmacological activities of ocotillol ginsenoside and glycine, and has a potential role in improving the delay of apoptosis and immunosuppression of ARDS neutrophil subtypes, and has the potential of new drug development for the treatment of ARDS. The experimental steps are as follows: Firstly, the peripheral blood of ARDS patients in ICU was collected, and neutrophils were isolated from the peripheral blood. The proportion of neutrophil subtypes and the degree of apoptosis were detected by flow cytometry. Co culture with human T lymphocytes in vitro to observe its ability to inhibit T cell proliferation. Then, the neutrophils of ARDS patients were cultured with different doses of ginsenoside glycine derivatives, and the detection of the above indexes was repeated again. Finally, the mechanism of neutrophils in the pathogenesis and progression of ARDS was discussed.
The three main chronic myeloproliferative disorders are polycythemia vera (PV), essential thrombocythemia (ET) and idiopathic myelofibrosis (IMF). These are clonal neoplastic diseases characterized by proliferation of one or more hematopoietic lineages. Recently a mutation of the Janus Kinase 2 (JAK2) gene that leads to the substitution of phenylalanine for valine at position 617 of the JAK2 protein, JAK2 V617F, has been found in 76% to 97% of patients with PV, 29% to 57% of patients with ET and 50% of patients with IMF. This mutation confers constitutive activity on to the JAK2 protein and appears to play an important role in the pathobiology of these conditions. However, not all patients with myeloproliferative disorders have this mutation and it may not be the primary cause of these diseases. The primary goal of this prospective natural history study is to investigate the molecular basis of these diseases in groups of patients who have JAK2 V617F and in those who do not. A second goal is to identify biomarkers for PV and the other myeloproliferative disorders that are easier to measure than JAK2 V617F. Approximately, 150 patients with myeloproliferative disorders will be studied over 3 years. The studies will involve the collection of 40 mL to 50 mL of peripheral blood from each subject. The blood will be used to assess neutrophil gene and protein expression, gene polymorphisms, and plasma protein levels.