New progress has been made in the clinical transformation of stem cell treatment of lung diseases in China
2020-07-23
In recent years, my country has made great progress in the field of stem cell treatment of lung diseases. Recently, according to the news published on the official website of the Drug Evaluation Center of the National Medical Products Administration, the domestic lung stem cell new drug clinical trial application has obtained clinical tacit approval for the treatment of early and mid-stage idiopathic pulmonary fibrosis, which is very exciting.
"Tumor-like diseases" for which there is no specific medicine
Pulmonary fibrosis is a chronic, progressive, fibrotic interstitial pneumonia, which is difficult to diagnose early. This is the end-stage change phenomenon of a large class of lung diseases characterized by fibroblast proliferation and a large amount of extracellular matrix accumulation accompanied by inflammatory damage and tissue structure destruction, that is, abnormality caused by abnormal repair after normal alveolar tissue is damaged Structure (scar formation).
Usually, the lung function of the patient shows a slow, gradual, and predictable downward trend. The patient has difficulty breathing during activities, and it gradually worsens, often accompanied by a dry cough. The rapid decline in lung function will reduce the quality of life of patients. If no intervention is performed, it will eventually lead to death, which is a very fatal disease. In recent years, the incidence and prevalence of pulmonary fibrosis have shown an upward trend year by year. The average survival time after diagnosis is only 2.8 years, and the mortality rate is higher than that of most tumors. It is called a "tumor-like disease."
There is currently no specific treatment for pulmonary fibrosis, mainly immunotherapy, anti-inflammatory, immunosuppressive, anti-fibrosis, anti-oxidation and other methods based on glucocorticoids, but the therapeutic effect is limited, so there is still an urgent need for development A new treatment for pulmonary fibrosis.
The clinical results of stem cell treatment of idiopathic pulmonary fibrosis are gratifying
In recent years, clinical studies on stem cells for the treatment of idiopathic pulmonary fibrosis have been carried out one after another, and clinical research results have been output successively.
In 2018, domestic studies reported the results of stem cell treatment of radiation pulmonary fibrosis. Eight patients were enrolled, and the pulmonary fibrosis lesions were lavaged through bronchoscopy and mesenchymal stem cells were injected in a single shot. All 8 patients were able to tolerate mesenchymal stem cell therapy, and no serious adverse reactions occurred during follow-up observation. Six patients reported improvement in shortness of breath, cough and other symptoms. CT showed a decrease in lung density, indicating that the mesenchymal stem cell therapy is safe and well tolerated; it can alleviate the patient's clinical symptoms and reduce the density of pulmonary fibrosis.
In 2019, "STEM CELLS Translational Medicine" (STEM CELLS Translational Medicine) reported the results of the first clinical study of high-dose stem cells in the human body to treat idiopathic pulmonary fibrosis with rapid decline in lung function [1]. A total of 20 subjects were recruited for the study, and they were randomly divided into two groups. The treatment group received intravenous infusion of mesenchymal stem cells twice every 3 months, each dose of 2*10^8 cells. The analysis of lung function indicators shows that mesenchymal stem cells can effectively curb the rapid progress of idiopathic pulmonary fibrosis and have certain therapeutic effects. The safety assessment did not find any significant adverse events related to treatment, indicating that high-dose cumulative mesenchymal stem cell transplantation is safe
The mechanism of mesenchymal stem cells in the treatment of pulmonary fibrosis
Mesenchymal stem cells are an important member of the stem cell family and have become one of the most promising stem cell types for the treatment of idiopathic pulmonary fibrosis.
Mesenchymal stem cells are derived from the early mesoderm and ectoderm. They were originally found in the bone marrow and have the characteristics of multi-directional differentiation potential, hematopoietic support and promotion of hematopoietic stem cell implantation, immune regulation and self-replication.
A large number of studies have confirmed that mesenchymal stem cells have powerful anti-inflammatory and immunomodulatory functions. They can reduce acute and chronic lung injury by inhibiting lung infiltrating immune cells, and reduce the secretion of inflammatory factors. At the same time, they can promote lung injury by secreting hepatocyte growth factor. The repair of alveolar epithelial cells further reduces the level of lung fibrosis.
Reduce pulmonary fibrosis through paracrine action: A study in the journal Stem Cell Translational Medicine in 2017 showed that mesenchymal stem cells reduce bleomycin-induced lung fibers through the paracrine action of lung cell growth factors化. Based on the anti-inflammatory, anti-fibrotic, anti-apoptotic and regeneration properties of cells, mesenchymal stem cells are widely regarded as drugs for the treatment of pulmonary fibrosis. Recently, there have been reports of increased levels of mesenchymal stem cells in the bronchoalveolar lavage fluid of pulmonary fibrosis animal models and patients. In mice with bleomycin-induced pulmonary fibrosis, transplantation of pretreated mesenchymal stem cells significantly improved lung respiratory function and down-regulated the expression of inflammatory and fibrotic factors in lung tissue. Histopathological examination showed pulmonary fibrosis Significant improvement.
Reduce pneumonia response by inhibiting apoptosis: Scientific research has also found that transplanted mesenchymal stem cells can significantly reduce pneumonia response by inhibiting the process of lung apoptosis, and can also inhibit the lung by inhibiting the expression of mitochondrial apoptosis-related proteins. Fibrosis process. Research data shows that mesenchymal stem cells may have a beneficial effect on pulmonary fibrosis. It represents a new way to treat pulmonary fibrosis and will further reveal the therapeutic potential of mesenchymal stem cells
Inhibiting the process of pulmonary fibrosis: Some scholars have discussed the efficacy of mesenchymal stem cell transplantation in animal models of pulmonary fibrosis after exposure to bleomycin. Research results show that mesenchymal stem cells can significantly inhibit the process of pulmonary fibrosis, providing a new treatment method for the treatment of pulmonary fibrosis [4].
Outlook
Today, thanks to the development of biomedical technology, mesenchymal stem cell transplantation has been widely used in clinical research for the treatment of pulmonary fibrosis. The results of the study show that patients are well tolerated and effectively curb the rapid deterioration of lung function caused by pulmonary fibrosis, indicating that mesenchymal stem cells have a considerable therapeutic effect on pulmonary fibrosis. It is believed that with the continuous output of breakthrough treatment results, the application prospects of stem cell therapy will become broader.
