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

• Published in: JBRA assisted reproduction Vol. 24; no. 1; pp. 13 - 19
• Main Authors: Terraciano, Paula Barros, Garcez, Tuane Alves, Berger, Markus, Durli, Isabel, Kuhl, Cristiana Palma, Batista, Vitória de Oliveira, Schneider, Raquel de Almeida, Festa, Jaquelline, Pilar, Emily, Ferreira, Charles, Passos, Eduardo Pandolfi, Lima, Elizabeth Cirne
• Format: Journal Article
• Language: English
• Published: Brazil Sociedade Brasileira de Reprodução Humana (Brazilian Society of Assisted Reproduction) 01.01.2020; Brazilian Society of Assisted Reproduction
• Subjects: Animals; Cryopreservation; Cryopreservation - methods; Drug overdose; Female; Fertility; Fertility Preservation - methods; Mice; Nitrogen; Original; Ovary - cytology; Ovary - physiology; Stem Cells - cytology; Stem Cells - physiology; Sucrose; Vitrification; California; stem cell; ovary; vitrification
• ISSN: 1518-0557; 1517-5693; 1518-0557
• DOI: 10.5935/1518-0557.20190057

The aim of this study was to investigate the efficacy of protocols for mice ovary cryopreservation to compare the differences in Mouse Vasa Homologue expression (a germline cell marker) and ovarian viability after vitrification or slow freezing. Female CF1 mice aged 40-45 days were randomly divided into three groups: Control, vitrification or slow freezing. Their ovaries were surgically removed, rinsed in saline solution and cryopreserved. For vitrification, we used a commercial protocol and for slow freeze, we used 1.5 M ethylene glycol (EG) as cryoprotectant. After that, the ovaries were processed for histological an immunohistochemical analysis, and counting of primordial, primary, pre-antral and antral follicles. No significant difference was found in the proportion of high-quality primordial, primary and pre-antral follicles after thawing/warming in the slow freezing and vitrification groups. The immunohistochemistry for MVH antibody demonstrated that the slow freeze group had a higher number of unmarked cells (p=0.012), indicating a harmful effect on the MVH expression in the ovarian tissue, where the cell structure is complex. Although both protocols indicated similar results in the histological analysis of follicular counts, the vitrification protocol was significantly better to preserve ovarian stem cells, an immature germ cell population. These cells are able to self-renew having regeneration potential, and may be effective for the treatment of ovarian failure and consequently infertility.