Oral Presentation ESA-SRB-ANZBMS 2024 in conjunction with ENSA

Impact of digital holographic microscopy on the viability of the preimplantation embryo (#171)

Battice N Westendorp 1 , Ané Kritzinger 2 , Ralf Mouthaan 2 , Darren JX Chow 1 3 4 , Kishan Dholakia 2 5 6 , Kylie R Dunning 1 3 4
  1. Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
  2. Centre of Light for Life, University of Adelaide, Adelaide, South Australia, Australia
  3. Australian Research Council Centre of Excellence for Nanoscale Biophotonics, University of Adelaide, Adelaide, South Australia, Australia
  4. Institute for Photonics and Advanced Sensing, University of Adelaide, Adelaide, South Australia, Australia
  5. School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia
  6. SUPA, School of Physics and Astronomy, University of st Andrews, North Haugh, St Andrews, United Kingdom

In clinical IVF, embryo quality assessments rely on subjective morphological inspection or an invasive biopsy for genetic screening. In most cases these approaches do not improve the live birth rate. Furthermore, an invasive biopsy is associated with an increased risk of preeclampsia following embryo transfer. Thus, development of an approach that is accurate and non-invasive would likely improve the success of clinical IVF and decrease the risk of pregnancy complications in this patient cohort. Previously, we demonstrated that digital holographic microscopy can rapidly and non-invasively assess embryo quality by measuring differences in refractive index (how light changes as it traverses through embryos). However, the potential impact of digital holographic microscopy on embryo viability remains unknown. To investigate this, we subjected murine embryos to imaging with digital holographic microscopy at the 2-, 4-, 8-cell, morula, or blastocyst stages (38-, 62-, 86-, 92-, 110-hours post-hCG administration, respectively) and compared these to non-imaged embryos (control). We assessed embryo developmental competence by their ability to reach the blastocyst-stage. To investigate more subtle impacts of imaging, we measured the level of DNA damage (yH2AX immunohistostaining) as well as the number of cells allocated to the divergent cell lineages of the blastocyst-stage embryo (immunohistostaining for inner cell mass: OCT-3/4; and trophectoderm: CDX2). We found that imaging embryos at the 2-, 4-, 8-cell or morula stages did not impact their ability to reach the blastocyst-stage (n=4 independent experimental replicates, representative of 36-40 embryos per stage; P>0.05). Potential subtle or sublethal impacts of daily imaging (DNA damage as well as allocation of cells to the inner call mass and trophectoderm) are ongoing. This study will demonstrate the potential of digital holographic microscopy as a safe and non-invasive method to assess embryo quality. This has the potential to be implemented in clinical practice, improving live birth rates following IVF.