Prevention of bone marrow mesenchymal stem cell transplantation against acute lung injury in rabbits

ABSTRACT

BACKGROUND:

The important pathological changes of acute respiratory distress syndrome (ARDS) is disruption of the lung alveolar-capillary membrane barrier and resultant pulmonary edema associated with a proteinaceous alveolar exudate. Bone marrow mesenchymal stem cells (BMSCs) are able to carry on dividing and renewing themselves, and can eventually develop into many other types of cells. This provides a new treatment for treating injury of lungs.

To investigate the prevention of endotoxin-induced acute lung injury in rabbit by BMSCs.DESIGN, TIME AND

The randomized controlled animal study was performed at the Central Laboratory of Tangdu Hospital from October 2007 to January 2008.MATERIALS A total of 20 rabbits were used in this study. Two rabbits were utilized to culture BMSCs. Eighteen rabbits were randomly assigned to three groups, saline control group, acute lung injury group and cell transplantation group (n = 6). Endotoxin was purchased from Sigma, USA.

Rabbit BMSCs were isolated and cultured by the Ficoll method. At the third passage, BMSCs were harvested for use.In the acute lung injury and call transplantation groups, endotoxin was infused into the trachea to establish models of acute lung injury/ARDS. Thirty minutes following model establishment, 2 mL BMSC suspension (1 x 105) was infused into the right jugular vein in the cell transplantation group. An equal volume of saline was injected into the saline control and acute lung injury groups.MAIN OUTCOME

Number of neutrophilic granulocyte, wet to dry weight ratio of lung tissue, protein content and pathological changes in lung tissue in bronchoalveolar lavage fluid were measured.

The increase in wet to dry weight ratio indicated the existence of pulmonary edema. The increase in neutrophilic granulocyte number suggested severe inflammatory reaction. The increased protein content showed the damage to lung alveolar-capillary membrane barrier. Following 48 hours of transplantation, neutrophilic granulocyte number and protein content in bronchoalveolar lavage fluid was significantly decreased (P < 0.01), and wet to dry weight ratio was significantly increased (P < 0.01) in the acute lung injury group compared with the saline control group. Compared with the acute lung injury group,neutrophilic granulocyte number and protein content was significantly increased (P < 0.01), and wet to dry weight ratio was significantly diminished (P < 0.01) in bronchoalveolar lavage fluid in the call transplantation group. Hematoxylin-eosin staining suggested that pulmonary alveoli was normal in the saline control group, presented typical acute lung injury in the acute lung injury group, and the pathological changes were mild in the cell transplantation group.

BMSC transplantation can significantly reduce endotoxin-induced acute lung injury.