title: Pregnancy-specific protein B induces release of an alpha chemokine in bovine endometrium.
abstract: Pregnancy-specific protein B (PSPB), is secreted from binucleate trophoblast of the bovine conceptus as early as day 15 of pregnancy. The objective of this experiment was to determine if PSPB induced uterine proteins. PSPB was purified from day 120 cotyledons using antibody-based affinity chromatography. Endometrium from day 14 nonpregnant cows (n = 3) was prepared for explant (3H-Leu added) culture. Radiolabeled proteins released into medium were dialyzed, separated using 1D-PAGE, and detected using fluorography and densitometry. PSPB (0, 0.5, 5, 25 & 50 nM) caused a concentration-dependent increase in the release of a radiolabeled 8-kDa uterine protein. Western blots revealed that the 8-kDa protein cross-reacted with antibody against granulocyte chemotactic protein-2 (GCP-2). PSPB also induced release of GCP-2 by bovine endometrial (BEND) cells in primary culture. The induction of GCP-2 by PSPB was blocked by addition of antiserum against PSPB (1:4 molar ratio). This is the first indication that PSPB has a hormonal role in inducing GCP-2, an alpha chemokine that also is induced by interferon-tau during early pregnancy. This chemotactic cytokine may be integral to mediating adhesion, inflammation and angiogenesis associated with early implantation.
authors.affiliation: Department of Animal Science, University of Wyoming, Laramie 82071, USA.
authors.forename: K J
authors.initials: KJ
authors.lastname: Austin
authors.forename: C P
authors.initials: CP
authors.lastname: King
authors.forename: J E
authors.initials: JE
authors.lastname: Vierk
authors.forename: R G
authors.initials: RG
authors.lastname: Sasser
authors.forename: T R
authors.initials: TR
authors.lastname: Hansen
mesh_terms: D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000494:pharmacology*; D002417:Cattle / Q000378:metabolism*; D002478:Cells, Cultured; D019743:Chemokines, CXC / Q000378:metabolism*; D004717:Endometrium / Q000187:drug effects / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D006031:Glycosylation; D007370:Interferon Type I / Q000494:pharmacology; D016898:Interferon-alpha / Q000494:pharmacology; D008970:Molecular Weight; D011257:Pregnancy Proteins / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D019743:Chemokines, CXC; D007370:Interferon Type I; D016898:Interferon-alpha; D011257:Pregnancy Proteins; D011994:Recombinant Proteins; C020947:interferon tau; D016282:Aspartic Acid Endopeptidases; C094766:pregnancy-associated glycoprotein 1