Label-free characterization of vitrification-induced morphology changes in single-cell embryos with full-field optical coherence tomography.
Vitrification is an increasingly popular method of embryo cryopreservation that is used in assisted reproductive technology. Although vitrification has high post-thaw survival rates compared to other freezing techniques, its long-term effects on embryo development are still poorly understood. We demonstrate an application of full-field optical coherence tomography (FF-OCT) to visualize the effects of vitrification on live single-cell (2 pronuclear) mouse embryos without harmful labels. Using FF-OCT, we observed that vitrification causes a significant increase in the aggregation of structures within the embryo cytoplasm, consistent with reports in literature based on fluorescence techniques. We quantify the degree of aggregation with an objective metric, the cytoplasmic aggregation (CA) score, and observe a high degree of correlation between the CA scores of FF-OCT images of embryos and of fluorescence images of their mitochondria. Our results indicate that FF-OCT shows promise as a label-free assessment of the effects of vitrification on embryo mitochondria distribution. The CA score provides a quantitative metric to describe the degree to which embryos have been affected by vitrification and could aid clinicians in selecting embryos for transfer.
Stanford University, Department of Bioengineering, 443 Via Ortega, Stanford, California 94305, United States.
Livia
L
Zarnescu
Stanford University, E.L. Ginzton Laboratory and Department of Electrical Engineering, 450 Serra Mall, Stanford, California 94305, United States.
Michael C
MC
Leung
Stanford University, IVF Laboratory, Lucille Packard Children's Hospital, 900 Welch Road, Suite 350, Stanford, California 94305, United States.
Michael
M
Abeyta
Stanford University, E.L. Ginzton Laboratory and Department of Electrical Engineering, 450 Serra Mall, Stanford, California 94305, United States.
Helge
H
Sudkamp
Stanford University, Stanford Photonics Research Center, 348 Via Pueblo Mall, Stanford, California 94305, United States.
Thomas
T
Baer
Stanford University, IVF Laboratory, Lucille Packard Children's Hospital, 900 Welch Road, Suite 350, Stanford, California 94305, United States.
Barry
B
Behr
Stanford University, E.L. Ginzton Laboratory and Department of Electrical Engineering, 450 Serra Mall, Stanford, California 94305, United States.
Audrey K
AK
Ellerbee
D000818:Animals; D015925:Cryopreservation; D004622:Embryo, Mammalian / Q000166:cytology* / Q000502:physiology; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D051379:Mice; D041623:Tomography, Optical Coherence / Q000379:methods*; D058989:Vitrification