Primordial germ cells (PGCs) are the germline precursors that give rise to oocytes and sperm, ensuring the continuation of life. While the PGC specification is extensively studied, it remains elusive how the PGC population is sustained and expanded after they migrate to embryonic gonads before birth. This study demonstrates that NRF1, a known regulator for mitochondrial metabolism, plays critical roles in post‐migrating PGC development. We show that NRF1 protein level gradually increases in post‐migrating PGCs during embryonic development. Conditional
Natural deep eutectic systems (NADES) are emerging as potential cryoprotective agents (CPA) for cell preservation. In this investigation, we develop an optimized CPA formulation using trehalose‐glycerol NADES (T:G) diluted in Normosol‐R and supplemented with isoleucine. Differential scanning calorimetry (DSC) is used to define the thermophysical properties of NADES‐based solutions, and Raman spectroscopy is used to characterize the effect of NADES on ice formation and hydrogen bonding. Jurkat cells are cryopreserved in each solution, and post‐thaw cell recovery, apoptosis, and growth are quantified. Raman spectra and heat maps show that NADES suppresses both ice formation and dehydration of the nonfrozen region. Supplementing NADES with isoleucine does not affect the solution's thermophysical properties but significantly improves the cells' survival and proliferation post‐thaw. The study indicates that thermophysical properties of CPA solutions alone cannot predict optimal cell survival, suggesting that stabilization of biological structures by CPAs may play a role in successful cryopreservation.
more » « less- NSF-PAR ID:
- 10454361
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- AIChE Journal
- Volume:
- 67
- Issue:
- 2
- ISSN:
- 0001-1541
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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