title: Placental alkaline phosphatase types and transplacental IgG transport.
abstract: Recently, results have been presented which suggest that placental alkaline phosphatase (PLAP) is an IgG receptor, and that the transplacental transport of IgG from mother to fetus is dependent on the fetal PLAP genotype. In order to confirm the relationship between the PLAP types and transplacental IgG transport, we studied fetal (cord serum) IgG levels in relation to PLAP types, quantitative variations in PLAP activity, maternal IgG levels and gestation length. Fetal IgG levels and the fetal/maternal IgG ratio showed no significant correlation with PLAP types and PLAP activity. Thus differences between PLAP types with respect to transplacental IgG transport are unlikely to play a selective role in the maintenance of the PLAP polymorphism. In accordance with results from previous studies, significant correlations were found with maternal IgG levels and gestation length. Perusal of the literature suggests that PLAP is mainly an IgG1 receptor.
authors.affiliation: Department of Medical Genetics, Umeå University, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Beckman
authors.forename: L
authors.initials: L
authors.lastname: Beckman
authors.forename: S
authors.initials: S
authors.lastname: Holm
authors.forename: C
authors.initials: C
authors.lastname: Sikström
authors.forename: C
authors.initials: C
authors.lastname: Wennberg
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism*; D000704:Analysis of Variance; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007527:Isoenzymes / Q000378:metabolism*; D008431:Maternal-Fetal Exchange / Q000502:physiology*; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy
chemical_list: D007074:Immunoglobulin G; D007527:Isoenzymes; C055791:germ-cell AP isoenzyme; D000469:Alkaline Phosphatase