| Purpose Obstructive pulmonary emphysema (pulmonary emphysema for short) means terminal bronchioles'elasticity including bronchioles, alveolar duct, and alveolar sac and alveolar respiratory weakens, excessively swells or inflatesa and lung capacity increases accompaning airway'wall impairing. Obstructive pulmonary emphysema usually coexisting chronic bronchitis and the general course of the disease longer. Once airway obstruction can't be returned and airflow becomes limited, COPD is diagnosed. It can be complicated with chronic pulmonary heart disease. At present, there is not effective therapy to revive the nonreversible emphysema.The main purpose for all therapies is to postpone the advance of emphysema and improve respiratory function, ameliorate patient'work and life ability.Stem cells are a kind of cells with self-renewal and differentiation potential. According to the survival stage, stem cell can be divided into embryonic stem cells and adult stem cells. The bone marrow mesenchymal stem cells (MSCs) have the largest study in current. MSCs are a kind of stem cell has a capcity for multi-directional differentiation in the bone marrow and various tissues.It has a strong capacity for plasticity and chemotaxis. MSCs could be migrating into the organization in the appropriate conditions while differentiate into a variety of cells from the mesoderm. Such as bone cells, cartilage cells, muscle cells, fat cells and other mesenchymal cell type. There are experimental evidences shows MSCs can differentiate into all germ layers across the system or organ tissue cells in a particular environment in vivo or in vitro. Such as neurons, liver cells, islet cells and renal tubular epithelial cells, lung epithelial cells and so on. In addition, MSCs has low immunogenicity and a strong immune inhibition, drawing convenient, easy to cultivate and amplified in vitro.the performance of MSCs is stable that has the capacity for self-renewal and multilineage differentiation after continuous passage and cryopreservation. It is not difficult to control the differentiation. MSCs have a low oncogenic risk. Finally, MSCs study would not face ethics dispute. Therefore, MSCs is a very potential application of adult stem cells.With nearly 20 years, the emergence of stem cell research has provided many new ideas for human diseases and shows the preliminary efficacy. In particular, the bone marrow mesenchymal stem cell research have emerged a large number of results in heart and cerebrovascular diseases, diabetes, liver disease and bone disease in the treatment of refractory. In contrast, the research of bone marrow-derived mesenchymal stem cells in lung disease shows a slow progress. This is mainly because the complexity of lung tissue structure and function different from other tissues and organs. Existing studies have mainly focused on interstitial lung disease (interstitiallungdisease, ILD), in particular, idiopathic pulmonary fibrosis (idiopathicpulmonaryfibrosis, IPF) and acute lung injury (ALI) and so on. In order to explore the role of MSCs in the pulmonary emphysema, the experiment conducted the following studies:1.Isolation culture and identifieation of mesenehymal stem eells.2.Making emphysema model in rat indued by exposure to cigarette and LPS.3.Transplant the MSCs of donors to injury models and evaluate the effect.Materials and methods1.1 Main reagents lipopolysaccharide (LPS), mouse anti-rat cytokeratin monoclonal antibody (PCK), Bromodeoxyuridine (Brdu), anti-Brdu monoclonal antibody, polymer double staining kit, large mouse TNF-a kit1.2 Methods:Thirty wistar rats were randomized into three groupe:normal control group, emphysema group, and emphysema+mscs transplantation groupe. The emphysema model of rats was established by intratracheal instillation of lipopolysaccharied (LPS) twice and daily exposure to cigaratte. Rats bone marrow-derived MSCs were separated,cultured,amplified and labled with bromodeoxyuridine (Brdu).Morphologic analysis of the lung tissue was performed. Bone marrow MSCs were infused through tail vein.Immunohistochemistry was used to detect.Brdu expression in the lung tissue. Enzyme-linked immunosorbent assay were used to dectect the levels of TNF-a in the lung tissue.Immunohistochemistry were used to detect wether the engrafed bone marrow MSCs express pneumocytes.Result Destruction of alveolar walls was observed in rat lungs from emphysema group and emphysema+mscs transplantation group. MSCs transplantation group significantly ameliorated the emphysematous changes. Compared with the emphysema group, the MSCs transplantation group presented significanted difference in the mean alveoli number (MAN)and pulmonary alveolar area(PAA).Immunohistochemistry showed Brdu-positive cell were detected in the emphysema+MSCs transplantation group, where some Brdu-positive cells express cytokeratin (CK),the marker of pneumocytes. Compare to normal control group, the levels of TNF-a in the emphysema group increased. The levels of TNF-aand inflammatory in the MSCs transplantation group significantly lower than those of normal control group.Conclusion:By intratracheal instillation of LPS and exposure to cigarette smoke successfully established the rat emphysema models. TO inject MSCs by tail vein may reside in the lungs of rats, significantly reduce the lung inflammation and pathological changes, which may be related to the MSCs differentiate into alveolar epithetical cells.
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