Different pattern of interleukin-1β-(IL-1β), interleukin-1 receptor antagonist- (IL-1ra) and interleukin-1 receptor type I- (IL-1R tI) mRNA-expression in single preimplantation mouse embryos at various developmental stages

• Published in: Journal of reproductive immunology 1997-09, Vol.34 (2), p.103-120
• Main Authors: Kruessel, J.S, Huang, H.-Y, Wen, Y, Kloodt, A.R, Bielfeld, P, Polan, M.L
• Format: Article
• Language: English
• Subjects: Animals; Blastocyst - metabolism; Culture Techniques - methods; DNA Primers; Embryo development; Embryonic and Fetal Development; Female; Interleukin 1 Receptor Antagonist Protein; Interleukin-1 - biosynthesis; Interleukin-1 - genetics; Interleukin-1 system; Mice; Polymerase Chain Reaction; Pregnancy; Preimplantation embryo; Receptors, Interleukin-1 - antagonists & inhibitors; Receptors, Interleukin-1 - biosynthesis; Receptors, Interleukin-1 - genetics; Receptors, Interleukin-1 Type I; RNA, Messenger - analysis; RT/PCR; Sialoglycoproteins - biosynthesis; Sialoglycoproteins - genetics
• ISSN: 0165-0378; 1872-7603
• DOI: 10.1016/S0165-0378(97)00030-2

The interleukin-1 (IL-1) system has been shown to play an important role in human and murine embryo implantation. Recent studies have documented immunohistochemical evidence of interleukin-1β (IL-1β), interleukin-1 receptor antagonist (IL-1ra) and interleukin-1 receptor type I (IL-1R tI) in human preimplantation embryos and protein levels of interleukin-1α (IL-1α), IL-1β and IL1ra in human preimplantation embryo culture fluid have been correlated with successful implantation and pregnancy. Our aim in this study was to detect IL-1β, IL-1ra and IL-1R tI mRNA in single preimplantation mouse embryos and to describe the frequency of positive mRNA-expression at different developmental stages. B6C3F1-mice, 12 weeks old were pregnant mare serum gonadotropin (PMSG)/human chorionic gonadotropin (hCG)-stimulated and mated. Animals were sacrificed at day 0.5, and zygotes were flushed from the tubes and cultured in HAMs-F10 medium. 2-cell- (2C-), 8-cell- (8C-), morula- (M-), early blastocyst- (EB-) and hatching blastocyst- (HB-) stage embryos were examined by one round of reverse transcriptase (RT) followed by two rounds of polymerase chain reaction (PCR) carried out on individual mouse embryos for β-actin (internal standard), IL-1β, IL-1ra and IL-1R tI-mRNAs. The frequencies of positive mRNA-expressions were as follows (2C/8C/M/EB/HB); β-actin: 91/96/100/100/98%; IL-1b: 0/0/2.5/6.25/19; IL-1ra; 0/5/30/41/74% and IL-1R tI: 0/0/10/20/25%. The incidence of IL-1ra mRNA expression increased with developmental stage. IL-1ra mRNA seems to be expressed in a very high percentage (74%) of embryos near the time of implantation, whereas the percentage of IL-1β-mRNA positive embryos is surprisingly low (19%).