All issues > Volume 41(4); 1998

Original Article

J Korean Pediatr Soc. 1998;41(4):472-480. Published online April 15, 1998.

Preparation and in vitro Physical Activities of Crude Natural Surfactant and Artificial Pulmonary Surfactant Containing Synthetic Peptide and Phospholipid Mixtures

Joo Hyun JH Kang¹, Song Yub SY Shin¹, Cheol-Young CY Maeng², Kil Lyong KL Kim², Chong-Woo CW Bae², Kyung-Soo KS Hahm²

¹Peptide Engineering Research Unit, Korea Research Institute of Bioscience and Biotechnology, KIST
²Department of Pediatrics, College of Medicine, Kyunghee University, Seoul, Korea

Correspondence Kyung-Soo KS Hahm ,Email: 1

Abstract

Purpose
: In this study, natural pulmonary surfactant was extracted from bovine lung lavage and its surface activity was determined. To investigate the usefulness of synthetic peptides reconstituted with phospholipid as artificial surfactant, truncated peptides from surfactant protein (SP)-B were synthesized and restored the surface tension lowering activities when appropriately recombined with phospholipid.
Methods
: Crude natural surfactant(CNS) was isolated from lung lavage by centrifugation and organic solvent for the extraction of pulmonary surfactant was selected to satisfy the in vitro physical properties. Two truncated peptides derived from C-terminal end of bovine SP-B hydrophobic protein were selected and synthesized. To prepare artificial surfactant, synthetic peptides was added to the phospholipid mixture. The various surfactant mixtures were assayed for in vitro physical activity with the Wilhemly plate method and were determined by surface spreading rate, surface adsorption rate and surface tension-area diagram.
Results
: CNS-chloroform methanol(CM) displayed efficient surface activity compared with clinically used SurfactenⓇ but CNS-BuOH did not. The artificial surfactants containing phospholipid mixture and synthetic peptide were analyzed for their surface activities and displayed significant surfactant properties.
Conclusion
: 1-Butanol or CM(3:1) was used as an extraction solvent for CNS. CNS-CM showed more efficient surface activity than CNS-BuOH. Two synthetic peptides composing artificial pulmonary surfactant were designed and mixing ratio of peptide and phospholipid was established. Artificial surfactant dispalyed weaker surface activity than natural surfactant but significant surfactant activity.

Keywords :Surfactant protein(SP)-B, Surface tension, Synthetic peptide, Respiratory distress syndrome, Wilhemly plate method