Oral Presentation ESA-SRB-APEG-NZSE 2022

Utilising a micro-device for simplifying and improving ART (#19)

Cheow Yuen (Tiffany) Tan 1 2 3 , Suliman Yagoub 1 2 3 , Megan Lim 1 2 3 , Darren Chow 1 2 3 , Anthony Orth 4 , Brant Gibson 1 5 , Kishan Dholakia 6 7 8 , Jeremy Thompson 1 2 3 9 , Kylie Dunning 1 2 3
  1. Australian Research Council (ARC) Centre of Excellence for Nanoscale BioPhotonics (CNBP), University of Adelaide, Adelaide, SA, Australia
  2. Institute for Photonics and Advanced Sensing (IPAS), University of Adelaide, Adelaide, SA, Australia
  3. School of Biomedicine, Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia
  4. National Research Council of Canada, Ottawa, ON, Canada
  5. School of Science, RMIT, Melbourne, Victoria, Australia
  6. School of Physics and Astronomy, University of St Andrews, North Haugh, Scotland, United Kingdom
  7. School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
  8. Department of Physics, College of Science, Yonsei University, Seoul , South Korea, Korea
  9. Fertilis Pty Ltd, Adelaide, SA, Australia

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Image legend: Design and fabrication of a device on the micron scale for oocyte microinjection and cryopreservation.

Abstract: Intracytoplasmic sperm injection (ICSI) and oocyte cryopreservation are important assisted reproductive technologies routinely performed in clinical IVF. However, both procedures are technically challenging, requiring manual handling by highly skilled embryologists and adherence to stringent time frames. The stress induced by these processes may lead to poor clinical outcomes. Therefore, we hypothesised that minimisation of oocyte handling will simplify both procedures and in turn, improve IVF outcomes. To address this, we designed and fabricated a micrometre-scale device that houses multiple oocytes in a linear array. The device was fabricated by two-photon polymerisation and consisted of two components: the Pod and Garage. An individual oocyte is housed within a Pod, with multiple Pods docked into a Garage. To demonstrate the utility of this device for ICSI, presumptive zygotes were microinjected with fluorescent microspheres within the device and cultured to the blastocyst stage. Compared to standard culture, the Pod and Garage had no impact on embryo development and DNA damage levels in resultant blastocysts. Importantly, the device allowed for ICSI to be performed without the need of a holding pipette, thus simplifying the process. To evaluate the suitability of this device for cryopreservation, we demonstrated that the device could withstand repeated freeze-warm cycles with no observable structural impact. Vitrification and warming of oocytes within the device had comparable survival, developmental competency, and metabolic profile to those vitrified using standard practice. Importantly, the device allowed for reduced manual handling of oocytes during cryopreservation. Additionally, vitrification within the device occurred within 3 nL – an approximate 1000-fold reduction in the volume of cytotoxic cryoprotectant solution compared to standard practice. Overall, this work demonstrated the capability of this device to simplify the technically challenging procedures of ICSI and oocyte cryopreservation and may lead to improved outcomes for patients.

Conflict of interests: J. G. Thompson is a Director and Chief Scientific Officer of Fertilis Pty Ltd. All the other authors declare no competing interests. A PCT patent (PCT/AU2020/051318) has been granted.