INTERFERON-GAMMA PRODUCTION BY THE HUMAN PREIMPLANTATION EMBRYO

PROBLEM: This study demonstrated that the human embryo produces interf eron-gamma (IFN gamma). It is important to know whether IFN gamma can be produced before implantation. Therefore the aim of this study was t o evaluate the profile of IFN gamma production between days 2 and 5 af ter in vitro fertilization. METHOD: Twenty embryos were cultured from day 2 to 5 after fertilization. The embryo stages were checked each da y and the media refreshed. IFN gamma levels were estimated by an enzym e-linked immunosorbent assay. RESULTS: All embryos produced measurable IFN gamma at least for 1 day. Yields of IFN gamma were: 0.46 +/- 0.45 (n = 4) on day 2, 0.69 +/- 0.52 (n = 19) on day 3, 0.73 +/- 0.52 (n = 15) on day 4, 0.55 +/- 0.32 (n = 11) IU/ml on day 5, respectively. Th ere n as no significant difference in the IFN gamma production between in vitro culture days or between the developmental stages of embryos. CONCLUSION: IFN gamma is produced by all the embryos and seems to peak between days 3 and 4, which is just before implantation.