Lysis of RBc Membrane and Type II Alveolar Epithelial Cell Toxicity by Various Artificial Pulmonary Surfactants Used in Korea

Park, Eun Ae; Lee, Kyung Eun; Kim, Gyoung Hee

Abstract

PURPOSE: Surfactant replacement therapy is now recognized as a life saving and safe intervention in small premature infants with respiratory distress syndrome. The incidence of pulmonary hemorrhage is increased in association with artificial surfactant therapy in extremely low birth weight infants, but the pathogenesis is not clear. We conducted this study to prove whether exposure of RBC or type II alveolar epithelial cell membrane to various artificial pulmonary surfactants may lead to increased membrane permeability.
METHODS
1) Washed packed red blood cells(30 pl) with various concentration of SurfactenR, NewfactanR, CurosurfR, and ExosurfR were incubated for either 2 or 24 hours at 37 degrees C. Hemolysis was measured by spectrophotometry. 2) Type II alveolar epithelial cell(HTB-181) (105cell/Ml) with various concentrations of above artificial surfactants were incubated for 24 hours at 37 degrees C. Lactate dehydrogenase (LDH) release was measured as an indicator of cytotoxicity.
RESULTS
1) Concentrationdent hemolysis of RBC membrane with each artificial surfactant for 2 or 24 hours was observed. Especially for 24 hours incubation, hemolysis with ExosurfR was significantly higher than with other artificial surfactants at concentration up to 2.5 mg/2 mL(P<0.05). 2) Exposure of 105 cells to 6 mg of all artificial surfactants led to a maximum release of LDH from cells into the media. At the concentration of 6 mg, release of LDH with ExosurfR was significantly higher than SurfactenR and NewfactanR (P< 0,05). There was no difference between SurfactenR, NewfactanR, and control group.
CONCLUSION
Artificial surfactant may be associated with in vitro cytotoxicity and this property differs for different dosage and exposure time. Especially purely synthetic artificial surfactant(ExosurfR) is more potent in inducing lysis of RBC and type II alveolar epithelial cell.