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

Kang, Joo Hyun; Shin, Song Yub; Maeng, Cheol-Young; Kim, Kil Lyong; Bae, Chong-Woo; Hahm, Kyung-Soo

Original Article

Journal of the Korean Pediatric Society 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 Kang¹, Song Yub Shin¹, Cheol-Young Maeng², Kil Lyong Kim², Chong-Woo Bae², Kyung-Soo Hahm²

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

천연 폐 계면활성제 및 합성펩타이드와 인지질 혼합물을 이용한 폐 계면활성제의 제조와 표면활성의 물리적 특성에 관한 연구

강주현^¹^, 신송엽^¹^, 맹철영^²^, 김길룡^²^, 배종우^²^, 함경수^²

^¹생명공학연구소 펩타이드공학 Research Unit
^²생명공학연구소 펩타이드공학 Research Unit

Correspondence:
Kyung-Soo 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.

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