title: Immunoassay for the determination of surfactant apoprotein (SP-A) in human amniotic fluid: comparison with other indices of assessing foetal lung maturity.
abstract: The concentration of the major surfactant-associated protein SP-A (28-36 kDa) was determined in 73 amniotic fluid samples obtained from normal (n = 40) and complicated (n = 33) pregnancies. Lecithin/sphingomyelin (L/S) ratio and phosphatidylglycerol (PG) levels were also determined in all the samples by one-dimensional step-wise thin-layer chromatography. An enzyme-linked immunosorbent assay was used to determine human lung surfactant apoprotein SP-A. The amount of SP-A in human amniotic fluid increased as a function of gestational age from 8 mg l-1 at 36 weeks to 11.75 mg l-1 at 40-41 weeks of gestation. There was a significant difference (p less than 0.01) in amniotic fluid SP-A concentration from female (9.93 +/- 0.60 micrograms ml-1) compared to male (9.10 +/- 0.52 micrograms ml-1) foetuses. In amniotic fluid samples obtained from a group of complicated pregnancies, SP-A levels were significantly lower than in the normal group when adjusted for gestational age and sex of the foetus (p less than 0.05).
authors.affiliation: Department of Obstetrics & Gynaecology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: A
authors.initials: A
authors.lastname: Wali
authors.forename: K
authors.initials: K
authors.lastname: Dhall
authors.forename: S N
authors.initials: SN
authors.lastname: Sanyal
authors.forename: R
authors.initials: R
authors.lastname: Juneja
authors.forename: S
authors.initials: S
authors.lastname: Majumdar
mesh_terms: D000653:Amniotic Fluid / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005325:Fetal Organ Maturity; D005865:Gestational Age; D006801:Humans; D008168:Lung / Q000196:embryology*; D008297:Male; D010713:Phosphatidylcholines / Q000032:analysis; D010715:Phosphatidylglycerols / Q000032:analysis; D011247:Pregnancy; D011296:Prenatal Diagnosis; D011510:Proteolipids / Q000032:analysis*; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000032:analysis*; D013109:Sphingomyelins / Q000032:analysis
chemical_list: D010713:Phosphatidylcholines; D010715:Phosphatidylglycerols; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D013109:Sphingomyelins