The expression and activity of Toll-like receptors in the preimplantation human embryo suggest a new role for innate immunity

AbstractSTUDY QUESTIONIs the innate immunity system active in early human embryo development?SUMMARY ANSWERThe pattern recognition receptors and innate immunity Toll-like receptor (TLR) genes are widely expressed in preimplantation human embryos and the pathway appears to be active in response to TLR ligands.WHAT IS KNOWN ALREADYEarly human embryos are highly sensitive to their local environment, however relatively little is known about how embryos detect and respond to specific environmental cues. While the maternal immune response is known to be key to the establishment of pregnancy at implantation, the ability of human embryos to detect and signal the presence of pathogens is unknown.STUDY DESIGN, SIZE, DURATIONExpression of TLR family and related genes in human embryos was assessed by analysis of published transcriptome data (n  = 40). Day 5 (D-5) human embryos (n = 25) were cultured in the presence of known TLR ligands and gene expression and cytokine production measured compared to controls.PARTICIPANTS/MATERIALS, SETTING, METHODSHuman embryos surplus to treatment requirements were donated with informed consent from several ART centres. Embryos were cultured to Day 6 (D-6) in the presence of the TLR3 and TLR5 ligands Poly (I: C) and flagellin, with gene expression measured by quantitative PCR and cytokine release into medium measured using cytometric bead arrays.MAIN RESULTS AND THE ROLE OF CHANCETLR and related genes, including downstream signalling molecules, ...
Source: Human Reproduction - Category: Reproduction Medicine Source Type: research