USE OF REVERSE TRANSCRIPTION-POLYMERASE CHAIN-REACTION TO DETECT EMBRYONIC INTERLEUKIN-1 SYSTEM MESSENGER-RNA IN INDIVIDUAL PREIMPLANTATIONMOUSE EMBRYOS COCULTURED WITH VERO CELLS

In this study, we report a total of 292 mouse embryos cultured on Vero cell monolayers and 77 embryos cultured in medium alone at different preimplantation stages examined individually for embryonic mRNA of bet a-actin, interleukin-1 beta (IL-1 beta), interleukin-1 receptor antago nist (icIL-1ra) and interieukin-1 receptor type I(IL-1RtI) using rever se transcription and two-step polymerase chain reaction (RT-PCR). The rates of blastocyst formation and blastocyst hatching were both signif icantly higher in embryos co-cultured with Vero cells in comparison wi th the embryos cultured in control medium (81.2 +/- 2.6 versus 42.2 +/ - 3.7%, P < 0.001; 75.6 +/- 2.7 versus 19.2 +/- 6.2%, P < 0.001 respec tively), We have identified a similar pattern of interleukin-1 family embryonic mRNA transcripts expressed from the compact morula stage thr ough to hatching blastocyst in both control and Vero cell cultured emb ryos with significantly increased icIL-1ra transcript at hatching blas tocyst stage (P < 0.05, P < 0.001 respectively). There was a significa nt increase in IL-1 beta mRNA transcripts of embryos at hatching blast ocyst stage compared to compact morula stage in Vero cell cultured emb ryos (P < 0.05). These findings support the hypothesis that the IL-1 s ystem is an important factor in embryo-maternal molecular communicatio n during the implantation process.