Ovarian tissue vitrification is more efficient than slow freezing to preserve ovarian stem cells in CF-1 mice

Investigating cryopreservation techniques for maintaining morphology and in vitro viability of cartilage and skin from Spix's yellow-toothed cavies (Galea spixii Wagler, 1831) for conservation through biobanks

Conservation of the genetic diversity through skin and cartilage biobanks represents an essential strategy for maintaining biodiversity. Biobanks for the wild species of the order Rodentia have been little studied. Considering that the cryopreservation technique has specific relationships with the tissue and species of interest, we propose investigating different techniques for preserving tissue integrity and cell viability after cartilage and skin culture from Spix's yellow-toothed cavies. Subsequently, two techniques [solid-surface vitrification (SSV) vs. slow freezing (SF)] were used for cartilage and skin cryopreservation. Tissues not subjected to cryopreservation were used as controls. All tissues were evaluated for morphology and proliferation by histological techniques. Moreover, fragments were cultured, and cells were evaluated for viability, proliferation, metabolism, and apoptosis. Regardless of the cryopreservation technique, no differences were observed for the thickness of the epidermis, dermis, skin, spinous and basal layers, fibroblasts, and proliferative activity regarding the number of nucleolar organizer regions (NOR). SSV ensured better maintenance of epidermal cells, normal chondrocytes, filled gaps, collagen fibers, proliferative activity by NOR area/cell, and reduced perinuclear halos and empty gaps compared to SF. SF ensured the conservation of corneum thickness compared to the control. Although both techniques promoted cell recovery after culture, cells from SF resulted in better subconfluence time and day with cell growth around fragments compared to SSV. In conclusion, both cryopreservation techniques resulted in viable cells after culture. However, SSV promoted better maintenance of tissue morphological integrity, and SF ensured the preservation of all cell quality parameters in Spix's yellow-toothed cavies.

Impacts of vitrification on the transcriptome of human ovarian tissue in patients with gynecological cancer

Objective: This study investigated the effects of a vitrification/warming procedure on the mRNA transcriptome of human ovarian tissues.

Design: Human ovarian tissues were collected and processed through vitrification (T-group) and then subjected to RNA sequencing (RNA-seq) analysis, HE, TdT-mediated dUTP nick-end labeling (TUNEL), and real-time quantitative PCR, and the results were compared to those of the fresh group (CK).

Results: A total of 12 patients, aged 15–36 years old, with a mean anti-Müllerian hormone level of 4.57 ± 3.31 ng/mL were enrolled in this study. According to the HE and TUNEL results, vitrification effectively preserved human ovarian tissue. A total of 452 significantly dysregulated genes (|log2FoldChange| > 1 and p < 0.05) were identified between the CK and T groups. Among these, 329 were upregulated and 123 were downregulated. A total of 372 genes were highly enriched for 43 pathways (p < 0.05), which were mainly related to systemic lupus erythematous, cytokine–cytokine receptor interaction, the TNF signaling pathway, and the MAPK signaling pathway. IL10, AQP7, CCL2, FSTL3, and IRF7 were significantly upregulated (p < 0.01), while IL1RN, FCGBP, VEGFA, ACTA2, and ASPN were significantly downregulated in the T-group (p < 0.05) compared to the CK group, which agreed with the results of the RNA-seq analysis.

Conclusion: These results showed (for the first time to the authors’ knowledge) that vitrification can induce changes in mRNA expression in human ovarian tissues. Further molecular studies on human ovarian tissues are required to determine whether altered gene expression could result in any downstream consequences.