Cryopreservation of nuclear material as a potential method of fertility preservation  Zhiying He, M.S., Hung-Ching Liu, Ph.D., Zev Rosenwaks, M.D.  Fertility and Sterility  Volume 79, Issue 2, Pages 347-354 (February 2003) DOI: 10.1016/S0015-0282(02)04674-5

FIGURE 1 Isolation and packaging of female pronuclei for cryopreservation. (A), Female pronuclei were isolated from zygotes by micromanipulation. (B), The isolated pronuclei were packed into an empty donor zona pellucida by an enucleation pipette. He. Embryogenesis from preserved female pronuclei. Fertil Steril 2003. Fertility and Sterility 2003 79, 347-354DOI: (10.1016/S0015-0282(02)04674-5)

FIGURE 2 Assessment of nuclei viability. The viability of thawed nuclear materials (i.e., female pronuclei or second polar bodies) was evaluated by propidium iodide and Hoescht 33342 dual staining. After staining, pictures were taken under a light microscope (A), fluorescence microscope with Texas red filter (B), under fluorescence microscope with DAP1 filter (C), or under fluorescence microscope with DAP1/fluorescein/Texas red triple-filter (D). He. Embryogenesis from preserved female pronuclei. Fertil Steril 2003. Fertility and Sterility 2003 79, 347-354DOI: (10.1016/S0015-0282(02)04674-5)

FIGURE 3 Reconstructed mice, recipients, and their offspring. (A), Reconstructed B6D2F1 mice (ebony) after nuclear transfer of cryopreserved second polar bodies and their CD1 recipient (white). (B), Three generations of mice. The first generation CD1 recipient (white), second generation reconstructed mice (big ebony), and the third generation offspring (4 small ebony). He. Embryogenesis from preserved female pronuclei. Fertil Steril 2003. Fertility and Sterility 2003 79, 347-354DOI: (10.1016/S0015-0282(02)04674-5)