Interferon Production by the Preimplantation Sheep Embryo
- 1 April 1989
- journal article
- research article
- Published by Mary Ann Liebert Inc in Journal of Interferon Research
- Vol. 9 (2) , 175-187
- https://doi.org/10.1089/jir.1989.9.175
Abstract
Ovine trophoblast protein-1 (oTP-1), the major product secreted by the trophectoderm of the sheep conceptus between days 13 and 21 of pregnancy, is considered to mediate maternal recognition of pregnancy by maintaining the function of the corpus luteum. Its amino acid sequence has 40–55% identity with various mammalian interferons-α (IFN-α), and it has been shown to have antiviral activity. The present results confirm that oTP-1, which at days 15–17 of pregnancy is produced by a single embryo at more than 100 μg (>1 million antiviral units) per day, is a functional IFN. A preparation of purified oTP-1 was made. Its amino-terminal sequence suggested that it consisted of a single homogeneous protein, so that its antiviral activity probably was not due to a contaminant. In a cytopathic effect inhibition assay with GBK-2 bovine cells challenged with vesicular stomatitis, its specific activity was 1.3 × 107 end point units/mg protein. It also protected GBK-2 cells against four other viruses, and A549 human cells against encephalomyocarditis virus. The antiviral activity was neutralized by an antiserum to human leukocyte IFN. Like human IFN-α, oTP-1 at concentrations as low as 10−9 M inhibited the growth of GBK cells in culture and suppressed mitogen-stimulated incorporation of [3H]thymidine into ovine lymphocytes. Possible roles for oTP-1, functioning as an IFN-α during early pregnancy, are discussed.This publication has 32 references indexed in Scilit:
- Ovine Trophoblast Protein-i and Bovine Trophoblast Protein-i are Present as Specific Components of Uterine Flushings of Pregnant Ewes and Cows1Biology of Reproduction, 1988
- Antiviral activity of the pregnancy recognition hormone ovine trophoblast protein-1Biochemical and Biophysical Research Communications, 1988
- High homology between a trophoblastic protein (trophoblastin) isolated from ovine embryo and α‐interferonsFEBS Letters, 1988
- Purification of the InterferonsJournal of Interferon Research, 1987
- INTERFERONS AND THEIR ACTIONSAnnual Review of Biochemistry, 1987
- Interferon Inducibility and Sensitivity of Human Teratocarcinoma-Derived Cell LinesJournal of Interferon Research, 1987
- Preferential modulation of embryonic cell proliferation and differentiation by embryonic interferonExperimental Cell Research, 1986
- Developmentally Regulated Expression of the Interferon System During Syrian Hamster EmbryogenesisJournal of Interferon Research, 1984
- The structure of one of the eight or more distinct chromosomal genes for human interferon-αNature, 1980
- Identification of an interferon in murine placentasNature, 1980