Biomaterial Database

Isolation of human surfactant protein A from amniotic fluid. 1995

K B Cheong, and S K Cheong, and N Y Boo, and M Jemilah, and S H Ton

Department of Pathology, Universiti Kebangsaan Malaysia, Kuala Lumpur.

Surfactant protein A (SP-A) is one of the four known surfactant-associated proteins found in human lungs. It plays a major role in determining regulation of surfactant uptake and resecretion. Qualitative and quantitative deficiencies of SP-A may contribute to neonatal respiratory distress syndrome. The measurement of its level in amniotic fluid or neonatal tracheal aspirate may be useful in the assessment of replacement therapy using natural or synthetic surfactants. In order to develop an in-house immunoassay to detect the level of SP-A, we used a discontinuous sucrose density gradient to isolate SP-A from amniotic fluid. Polyacrylamide gel electrophoresis was carried out on the isolates with low molecular weight markers. We successfully isolated SP-A from 12 out of 31 samples of amniotic fluid. The isolates were found to be relatively pure and have a molecular weight of about 35 kD. The isolated SP-A were used as immunogens to raise antibodies in rabbits for the immunoassay.

UI	MeSH Term	Description	Entries
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011510	Proteolipids	Protein-lipid combinations abundant in brain tissue, but also present in a wide variety of animal and plant tissues. In contrast to lipoproteins, they are insoluble in water, but soluble in a chloroform-methanol mixture. The protein moiety has a high content of hydrophobic amino acids. The associated lipids consist of a mixture of GLYCEROPHOSPHATES; CEREBROSIDES; and SULFOGLYCOSPHINGOLIPIDS; while lipoproteins contain PHOSPHOLIPIDS; CHOLESTEROL; and TRIGLYCERIDES.
D011663	Pulmonary Surfactants	Substances and drugs that lower the SURFACE TENSION of the mucoid layer lining the PULMONARY ALVEOLI.	Surfactants, Pulmonary,Pulmonary Surfactant,Surfactant, Pulmonary
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000653	Amniotic Fluid	A clear, yellowish liquid that envelopes the FETUS inside the sac of AMNION. In the first trimester, it is likely a transudate of maternal or fetal plasma. In the second trimester, amniotic fluid derives primarily from fetal lung and kidney. Cells or substances in this fluid can be removed for prenatal diagnostic tests (AMNIOCENTESIS).	Amniotic Fluid Index,Amniotic Fluid Indices,Amniotic Fluids,Fluid Index, Amniotic,Fluid Indices, Amniotic,Fluid, Amniotic,Fluids, Amniotic,Index, Amniotic Fluid,Indices, Amniotic Fluid
D037661	Pulmonary Surfactant-Associated Proteins	Proteins found in the LUNG that act as PULMONARY SURFACTANTS.	Lung-Surfactant Proteins,PSFAP,Pulmonary Surfactant-Associated Protein,Pulmonary Surfactant-Associated Proteolipid,Lung Surfactant Proteins,Proteins, Lung-Surfactant,Pulmonary Surfactant Associated Protein,Pulmonary Surfactant Associated Proteins,Pulmonary Surfactant Associated Proteolipid,Surfactant-Associated Protein, Pulmonary,Surfactant-Associated Proteins, Pulmonary,Surfactant-Associated Proteolipid, Pulmonary
D037662	Pulmonary Surfactant-Associated Protein A	An abundant pulmonary surfactant-associated protein that binds to a variety of lung pathogens, resulting in their opsinization. It also stimulates MACROPHAGES to undergo PHAGOCYTOSIS of microorganisms. Surfactant protein A contains a N-terminal collagen-like domain and a C-terminal lectin domain that are characteristic of members of the collectin family of proteins.	SP-A Protein,Surfactant Protein A,Pulmonary Surfactant Associated Protein A,SP A Protein