Model of micro-metastases of breast cancer cells in ovarian tissue: cryopreservation of ZR-75-1 and MDA-MB-231 cells with increased speed of warming increases malignancy

In medicine, ovarian tissue cryopreservation exists for fertility preservation of cancer patients. In fact, ovarian tissue frozen for subsequent thawing and re-transplantation can be contaminated with cancer cells. Therefore, investigations on the effect of cryopreservation on the post-thawed viability of such cells are relevant. Speed of warming is a key parameter of cell cryopreservation. However, the data about comparative viability of cancer cells cryopreserved with different parameters of warming are limited. The aim of our investigations was to assess the malignancy of cryopreserved cancer cells after conventional cooling followed by relatively slow and quick speed of warming. In vitro cultured breast cancer cells of lines ZR-75-1 and MD0MD-231 in form of compacted fragments (as a model of solid tumors) were frozen following a protocol usually used for freezing of ovarian tissue (6% ethylene glycol+6% glycerol+0.15M sucrose, -0.3°C/min). Cells were warmed by two routine regimes of warming: at 37°C ("slow" warming) and 100°C ("quick" warming). Biological properties of cells were investigated: viability, proliferation rate, 2D- and 3D-migration, transmembrane movement and invasion. Quick warming at 100°C in comparison with slow warming at 37°C exhibited significantly higher cell survival for MDA-MB-231 cells: 70.1% vs. 63.2% and for ZR-75-1 86.8% vs. 82.9%, respectively. The cell motility including 2D movement and 3D transmembrane migration were higher after quick thawing at 100°C. Invasive abilities of cells after cryopreservation were higher than that of fresh (non-treated cells). Both thawing regimes showed a similar rate of cell proliferation. Cryopreservation procedures, and especially this one with quick thawing, increase malignancy of ZR-75-1 and MDA-MB-231 breast cancer cells and risk of metastasis. These results cannot be directly extrapolated to other cryopreservation protocols or other cancer types.

Technology for Biobanking of Epididymal Spermatozoa from Patient with Obstructive Azoospermia: Case Report about Baby Born after Conventional Freezing Only with a Nonpermeable Cryoprotectant 360 kDa Polyvinylpyrrolidone

This publication reports, for the first time, the birth of a healthy child after intracytoplasmic sperm injection (ICSI) of motile spermatozoa after conventional ("slow") freezing of epididymal spermatozoa using 5% polyvinylpyrrolidone (PVP) of high molecular weight (360 kDa). Cryopreservation solution with 10% PVP was added to 30 µL of spermatozoa suspension in a 1:1 ratio, with a final PVP concentration of 5%. Then, polycarbonate capillaries for oocyte denudation with a diameter of 170 µm were filled with 60 µL of the resulting sperm suspension. After that, the capillaries were placed for 10 minutes at a height of 15 cm above liquid nitrogen and immersed into liquid nitrogen. To warm the spermatozoa, the capillaries were immersed in a water bath at a temperature of 40°C for 30 seconds. Oocyte fertilization was performed by ICSI. Zygotes were cultured in vitro for 5 days to the blastocyst stage. More than 100 spermatozoa were obtained after percutaneous epidydimal sperm aspiration, of which 80% were motile. After cryopreservation, storage for 3 months in liquid nitrogen, and thawing, 72% of the total sperm cells remained motile. Ten oocyte-cumulus complexes were found after follicle puncture, and eight metaphase II stage oocytes were fertilized using ICSI. After 18 hours, two pronuclei were found in seven (88%) of the oocytes. An analysis of the morphological characteristics of 5-day-old embryos showed that four (57%) of them reached the blastocyst stage. One embryo was transferred, and the remaining embryos were cryopreserved (vitrified). The onset of pregnancy was detected on the 14th day after embryo transfer, and one healthy girl (3300 g) was born at term.

Comparative Transcriptomic Analyses for the Optimization of Thawing Regimes during Conventional Cryopreservation of Mature and Immature Human Testicular Tissue

Cryopreservation of human testicular tissue, as a key element of anticancer therapy, includes the following stages: saturation with cryoprotectants, freezing, thawing, and removal of cryoprotectants. According to the point of view existing in "classical" cryobiology, the thawing mode is the most important consideration in the entire process of cryopreservation of any type of cells, including cells of testicular tissue. The existing postulate in cryobiology states that any frozen types of cells must be thawed as quickly as possible. The technologically maximum possible thawing temperature is 100 °C, which is used in our technology for the cryopreservation of testicular tissue. However, there are other points of view on the rate of cell thawing, according to how thawing should be carried out at physiological temperatures. In fact, there are morphological and functional differences between immature (from prepubertal patients) and mature testicular tissue. Accordingly, the question of the influence of thawing temperature on both types of tissues is relevant. The purpose of this study is to explore the transcriptomic differences of cryopreserved mature and immature testicular tissue subjected to different thawing methods by RNA sequencing. Collected and frozen testicular tissue samples were divided into four groups: quickly (in boiling water at 100 °C) thawed cryopreserved mature testicular tissue (group 1), slowly (by a physiological temperature of 37 °C) thawed mature testicular tissue (group 2), quickly thawed immature testicular tissue (group 3), and slowly thawed immature testicular tissue (group 4). Transcriptomic differences were assessed using differentially expressed genes (DEG), the Kyoto Encyclopedia of Genes and Genomes (KEGG), gene ontology (GO), and protein-protein interaction (PPI) analyses. No fundamental differences in the quality of cells of mature and immature testicular tissue after cryopreservation were found. Generally, thawing of mature and immature testicular tissue was more effective at 100 °C. The greatest difference in the intensity of gene expression was observed in ribosomes of cells thawed at 100 °C in comparison with cells thawed at 37 °C. In conclusion, an elevated speed of thawing is beneficial for frozen testicular tissue.

FeTPPS, a Peroxynitrite Decomposition Catalyst, Ameliorates Nitrosative Stress in Human Spermatozoa

Excessive levels of reactive nitrogen species (RNS), such as peroxynitrite, promote nitrosative stress, which is an important cause of impaired sperm function. The metalloporphyrin FeTPPS is highly effective in catalyzing the decomposition of peroxynitrite, reducing its toxic effects in vivo and in vitro. FeTPPS has significant therapeutic potential in peroxynitrite-related diseases; however, its effects on human spermatozoa under nitrosative stress have not been described. This work aimed to evaluate the in vitro effect of FeTPPS against peroxynitrite-mediated nitrosative stress in human spermatozoa. For this purpose, spermatozoa from normozoospermic donors were exposed to 3-morpholinosydnonimine, a molecule that generates peroxynitrite. First, the FeTPPS-mediated peroxynitrite decomposition catalysis was analyzed. Then, its individual effect on sperm quality parameters was evaluated. Finally, the effect of FeTPPS on ATP levels, motility, mitochondrial membrane potential, thiol oxidation, viability, and DNA fragmentation was analyzed in spermatozoa under nitrosative stress conditions. The results showed that FeTPPS effectively catalyzes the decomposition of peroxynitrite without affecting sperm viability at concentrations up to 50 μmol/L. Furthermore, FeTPPS mitigates the deleterious effects of nitrosative stress on all sperm parameters analyzed. These results highlight the therapeutic potential of FeTPPS in reducing the negative impact of nitrosative stress in semen samples with high RNS levels.

RNA Transcripts in Human Ovarian Cells: Two-Time Cryopreservation Does Not Affect Developmental Potential

Sometimes, for medical reasons, when a frozen tissue has already thawed, an operation by re-transplantation may be cancelled, and ovarian tissues should be re-frozen for transplantation next time. Research about the repeated cryopreservation of ovarian cells is rarely reported. It has been published that there is no difference in the follicle densities, proportions of proliferation of early preantral follicles, appearance of atretic follicles, or ultrastructural quality of frozen-thawed and re-frozen-rethawed tissue. However, the molecular mechanisms of a repeated cryopreservation effect on the developmental potential of ovarian cells are unknown. The aim of our experiments was to investigate the effect of re-freezing and re-thawing ovarian tissue on gene expression, gene function annotation, and protein-protein interactions. The morphological and biological activity of primordial, primary, and secondary follicles, aimed at using these follicles for the formation of artificial ovaries, was also detected. Second-generation mRNA sequencing technology with a high throughput and accuracy was adopted to determine the different transcriptome profiles in the cells of four groups: one-time cryopreserved (frozen and thawed) cells (Group 1), two-time cryopreserved (re-frozen and re-thawed after first cryopreservation) cells (Group 2), one-time cryopreserved (frozen and thawed) and in vitro cultured cells (Group 3), and two times cryopreserved (re-frozen and re-thawed after first cryopreservation) and in vitro cultured cells (Group 4). Some minor changes in the primordial, primary, and secondary follicles in terms of the morphology and biological activity were detected, and finally, the availability of these follicles for the formation of artificial ovaries was explored. It was established that during cryopreservation, the CEBPB/CYP19A1 pathway may be involved in regulating estrogen activity and CD44 is crucial for the development of ovarian cells. An analysis of gene expression in cryopreserved ovarian cells indicates that two-time (repeated) cryopreservation does not significantly affect the developmental potential of these cells. For medical reasons, when ovarian tissue is thawed but cannot be transplanted, it can be immediately re-frozen again.

Epigenetic Alterations in Cryopreserved Human Spermatozoa: Suspected Potential Functional Defects

Background: Gene set enrichment analysis (GSEA) was conducted on raw data, and alternative splicing (AS) events were found after mRNA sequencing of human spermatozoa. In this study, we aimed to compare unknown micro-epigenetics alternations in fresh and cryopreserved spermatozoa to evaluate the effectivity of cryopreservation protocols. Methods: Spermatozoa were divided into three groups: fresh spermatozoa (group 1), cryoprotectant-free vitrified spermatozoa (group 2), and conventionally frozen spermatozoa (group 3). Nine RNA samples (three replicates in each group) were detected and were used for library preparation with an Illumina compatible kit and sequencing by the Illumina platform. Results: Three Gene Ontology (GO) terms were found to be enriched in vitrified spermatozoa compared with fresh spermatozoa: mitochondrial tRNA aminoacylation, ATP-dependent microtubule motor activity, and male meiotic nuclear division. In alternative splicing analysis, a number of unknown AS events were found, including functional gene exon skipping (SE), alternative 5′ splice sites (A5SS), alternative 3′ splice sites (A3SS), mutually exclusive exon (MXE), and retained intron (RI). Conclusions: Cryopreservation of spermatozoa from some patients can agitate epigenetic instability, including increased alternative splicing events and changes in crucial mitochondrial functional activities. For fertilization of oocytes, for such patients, it is recommended to use fresh spermatozoa whenever possible; cryopreservation of sperm is recommended to be used only in uncontested situations.

Optimization of Follicle Isolation for Bioengineering of Human Artificial Ovary

Background: A functional artificial ovary is a promising strategy to recover fertility and restore endocrine function in cancer patients. The aim of this study is to optimize the follicle isolation protocol for cryopreserved human ovarian tissues. Methods: Each of the cryopreserved human ovarian cortex pieces (OCPs) from 10 patients was cut into two equal parts and randomly distributed into two treatment groups. Group 1: OCPs digested with Tumor Dissociation Enzyme (TDE); Group 2: OCPs digested with Liberase Dispase High (DH). The efficiency of both groups were evaluated in terms of yield, viability, morphology, and a short-term in vitro culture (IVC) in alginate scaffolds. Results: The TDE can isolate more primordial follicles and smaller diameter of follicles than Liberase DH. The TDE also enabled the isolation of more bright red follicles, higher percent of viable follicles, more morphologically normal follicles, and lower oxidative stress levels compared with Liberase DH. After eight days of IVC, follicles in the TDE group had a higher growth rate from Day 0 to Day 8, and higher viability on Day 8 than the Liberase DH Group. Conclusion: The TDE can be considered an alternative to Liberase DH, enables the isolation of a higher number of healthy follicles from human OCPs, and improves follicle survival after IVC in contrast to Liberase DH.

New method for cryoprotectant-free freezing of human oligoasthenoteratozoospremic spermatozoa with high-molecular polymer

Data about cryoprotectant-free cryopreservation of human ICSI spermatozoa are limited. The aim of this investigation was to compare two technologies for cryopreservation of spermatozoa from men with oligoasthenoteratozoospermia: standard conventional freezing with 5% glycerol (freezing in glycerol) and cryoprotectant-free freezing with 5% high-molecular-weight (360 kDa) polyvinylpyrrolidone (PVP) (PVP-freezing). Capillaries with spermatozoa were cooled in vapor and then plunginged into liquid nitrogen. Head-, midpiece- and tail-abnormality of spermatozoa, mitochondrial membrane potential (MMP) and DNA fragmentation rates after cryopreservation were evaluated. After warming of spermatozoa, fertilization of oocytes (ICSI) was performed. It was detected the lower rate of morphological abnormalities of PVP-frozen spermatozoa in comparison with cells frozen with glycerol (34.6 ± 4.1% vs. 20.7 ± 4.7%, respectively) (P < 0.05). Quality of cells with high MMP after warming in spermatozoa frozen with glycerol was lower than in PVP-frozen spermatozoa (34.7 ± 4.2 vs. 54.5 ± 4.2%, respectively) (P < 0.05). It was established that the DNA fragmentation rate in PVP-frozen spermatozoa was significantly lower in comparison with spermatozoa frozen with glycerol (23.1 ± 2.5% vs. 38.8 ± 3.0%, respectively) (P < 0.05). After fertilization (ICSI) of oocytes, it was established that cleavage and blastulation rates were higher in oocytes after fertilization with PVP-frozen spermatozoa than with spermatozoa frozen with glycerol. Fertilization-, development to 8-blastomeres-, and blastocyst-rates were for PVP-frozen and spermatozoa frozen with glycerol, respectively: 94.4 ± 7.8 vs. 82.2 ± 6.2% (P > 0.1 with tendency to increasing), 90.0 ± 4.6 vs. 69.5 ± 5.1% (P < 0.05), and 45.4 ± 4.1% vs. 30.9 ± 3.3% (P < 0.05). It was concluded that permeable cryoprotectant-free freezing with 5% high-molecular-weight (360 kDa) polyvinylpyrrolidone can be applied successfully for cryopreservation of human oligoasthenoteratozoospremic spermatozoa.

Unraveling Subcellular and Ultrastructural Changes During Vitrification of Human Spermatozoa: Effect of a Mitochondria-Targeted Antioxidant and a Permeable Cryoprotectant

Mitochondria-targeted antioxidants have great potential to counterbalance the generated reactive oxygen species (ROS) because they cross the inner membrane of the mitochondria. Still, their use was not reported in vitrified human spermatozoa. Our laboratory has successfully vitrified spermatozoa without the use of permeable cryoprotectants, but subcellular-level evidence was missing. Therefore, this study aimed to improve spermatozoa vitrification using a mitochondria-targeted antioxidant (mitoquinone, MitoQ), reveal ultrastructural changes in the spermatozoa due to the use of a permeable cryoprotectant, and report alterations of functional proteins during the spermatozoa vitrification process. For this, each of 20 swim-up-prepared ejaculates was divided into seven aliquots and diluted with a vitrification medium supplemented with varying concentrations of MitoQ (0.02 and 0.2 μM), glycerol (1, 4, and 6%), and a combination of MitoQ and glycerol. All aliquots were vitrified by the aseptic capillary method developed in our laboratory. The spermatozoa function assays revealed that the addition of either MitoQ (0.02 μM), glycerol (1%), or a combination of MitoQ (0.02 μM) and glycerol (1%) in the vitrification medium results in better or equivalent spermatozoa quality relative to the control. Transmission electron microscopy revealed that MitoQ protects the spermatozoa from undergoing ultrastructural alterations, but glycerol induced ultrastructural alterations during the vitrification process. Next, we performed label-free quantitative proteomics and identified 1,759 proteins, of which 69, 60, 90, and 81 were altered in the basal medium, 0.02 μM MitoQ, 1% glycerol, and Mito-glycerol groups, respectively. Actin, tubulins, and outer dense fiber proteins were not affected during the vitrification process. Some of the identified ubiquitinating enzymes were affected during spermatozoa vitrification. Only a few proteins responsible for phosphorylation were altered during vitrification. Similarly, several proteins involved in spermatozoa–egg fusion and fertilization (IZUMO1 and Tektin) were not affected during the vitrification process. In conclusion, MitoQ attenuates the vitrification-induced ultrastructural changes and alterations in the key proteins involved in spermatozoa functions and fertilization.

Emergency Fertility Preservation in a Young Woman With Non-Hodgkin Lymphoma

A nulliparous woman, age 25 years, had received a diagnosis of non-Hodgkin lymphoma (NHL) and now presented with stage IIA diffuse large B-cell lymphoma (DLBCL). According to her hematological oncologist's treatment plan, chemotherapy had to start immediately (within 1 week), with the patient receiving 6 courses of the standard R-CHOEP21 regimen (rituximab 375 mg/m², cyclophosphamide 750 mg/m², hydroxydaunorubicin 50 mg/m², vincristine 1.4 mg/m², etoposide 100 mg/m², prednisone 40 mg/m²). Due to potential risks of chemotherapy-induced gonadotoxicity and subsequent iatrogenic premature ovarian failure (POF) and fertility loss, the patient was referred to the reproductive medicine department for fertility preservation counseling and further management.

Construction and cryopreservation of an artificial ovary in cancer patients as an element of cancer therapy and a promising approach to fertility restoration

The proportion of cancer patients that survive is increasing because of improvements in cancer therapy. However, some cancer treatments, such as chemo- and radio-therapies, can cause considerable damage to reproductive function. The issue of fertility is paramount for women of childbearing age once they are cured from cancer. For those patients with prepubertal or haematogenous cancer, the possibilities of conventional fertility treatments, such as oocyte or embryo cryopreservation and transplantation, are limited. Moreover, ovarian tissue cryopreservation as an alternative to fertility preservation has limitations, with a risk of re-implanting malignant cells in patients who have recovered from potentially fatal malignant disease. One possible way to restore fertility in these patients is to mimic artificially the function of the natural organ, the ovary, by grafting isolated follicles embedded in a biological scaffold to their native environment. Construction and cryopreservation of an artificial ovary might offer a safer alternative option to restore fertility for those who cannot benefit from traditional fertility preservation techniques. This review considers the protocols for constructing an artificial ovary, summarises advances in the field with potential clinical application, and discusses future trends for cryopreservation of these artificial constructions.

Cryo-banking of human spermatozoa by aseptic cryoprotectants-free vitrification in liquid air: Positive effect of elevated warming temperature

Cryoprotectant-free vitrification is a common method for spermatozoa cryopreservation by direct plunging into liquid nitrogen. However, the commercial liquid nitrogen could be potentially contaminated by microorganisms. Warming temperature plays an essential role for quality of human spermatozoa after vitrification. This study aimed to evaluate comparatively a quality spermatozoa after vitrification in liquid nitrogen and clean liquid air as well as with two warming rates: at 42 °C and 45 °C. After performing of routine swim-up of normozoospermia samples, spermatozoa from the same ejaculate were divided into two groups: vitrified in liquid nitrogen (LN) and sterile liquid air (LA). Spermatozoa of LN group were warmed at 42 °C, and spermatozoa of LA groups were divided and warmed at 42 °C (LA42) and 45 °C (LA45). Then spermatozoa motility, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), reactive nitrogen species (RNS), and viability were assessed. It was no found significant differences in quality of spermatozoa from LN and LA groups in the motility, ROS, MMP, RNS rates after warming at 42 °C. A tendency to obtain better spermatozoa quality was found with using of warming by 42 °C in comparison with 45 °C. It was concluded that cryoprotectant-free vitrification by direct dropping of human spermatozoa into clean liquid air can be used as an alternative to cooling in liquid nitrogen. Warming of spermatozoa at 42 °C allows to preserve the spermatozoa physiological parameters.

In vitro activation of cryopreserved ovarian tissue: A single-arm meta-analysis and systematic review

OBJECTIVE

Primordial follicles in premature ovarian failure (POF) patients are very difficult to be activated spontaneously, so that mature oocytes are difficult to be obtained for in vitro fertilization. The aim of our review is to analyze and to systematize the published data regarding effectiveness of different strategies for in vitro activation of cryopreserved ovarian tissue.

STUDY DESIGN

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a review of the literature was performed for all relevant full-text articles published in PubMed in English. Meta-analysis conducted using STATA 14.0. The random-effects model was used to combine 8 study results because the examination of heterogeneity was minimal.

RESULTS

One hundred and seventy seven patients after in vitro activation treatment (IVA) of ovarian tissue had accumulatively 26 pregnancies through IVF or natural pregnancy and then produced 18 live births. The random-effects model showed that the total clinical pregnancy and baby born rates reported in 8 studies evidence about effectiveness of IVA.

CONCLUSION

In vitro activation of primordial follicles as a new potential treatment for ovarian disorder patients, can be a promising option for fertility preservation. Drug-free activation of ovarian tissue in comparison with drug-included activation seemed to be more efficient.

Patient with ovarian insufficiency: baby born after anticancer therapy and re-transplantation of cryopreserved ovarian tissue

Background

The second major cause of death is cancer. In fact, the effectiveness of anticancer treatments and positive long-term prognosis for young women has increased. However, the problem of post-cancer infertility plays a significant role, because chemotherapy can be gonadotoxic and lead to the functional death of ovaries. There is potential key solution to this problem: cryopreservation of ovarian tissue before cancer therapy with re-implantation after convalescence. Data regarding cryopreservation and re-transplantation of ovarian tissue from patients with ovarian insufficiency is limited. The aim of this treatment was the re-transplantation of cryopreserved ovarian tissue after anticancer therapy of patient with ovarian insufficiency (56 IU/l FSH, 8 ng/l β-estradiol, < 1.1 ng/ml anti-Mullerian hormone, 1 primary follicle per 10mm³).

Case presentation

After the operation, four tissue fragments (10–16 × 8–13 × 1.0–1.2 mm) were cooled to 5 °C in the freezing medium (culture medium+ 6% ethylene glycol+ 6% dimethyl sulfoxide+ 0.15 M sucrose) for 24 h, frozen and thawed. Freezing was performed in four standard 5 ml cryo-vials with ice formation at − 9 °C, cooling from − 9 to − 34 °C at a rate of − 0.3 °C/min and plunging at − 34 °C into liquid nitrogen. After thawing in a 100 °C (boiling) water bath, the removal of cryoprotectants was performed in 0.5 M sucrose with 20 min. exposure in sucrose and 30 min. stepping rehydration. After thawing of one cryo-vial, part (5 mm³) of experimental ovarian tissue after 7 day in vitro culture was histological evaluated and two ovarian fragments (8 × 7 × 1.0 mm and 7 × 6 × 1.0 mm) were re-transplanted. The quantity of follicles after cryopreservation and in vitro culture was not increased (P > 0.1): it was found 1 primordial follicle in 5 mm³ of tissue. Thirty seven days after the re-transplantation of ovarian tissue, the restoration of the menstrual cycle of Patient W. was noted. Three months after the transplantation, the patient became spontaneously pregnant and delivered a healthy baby girl at term.

Conclusions

Described protocol of conventional cryopreservation of ovarian tissue can be used for treatment of patients with ovarian insufficiency.

Increasing of malignancy of breast cancer cells after cryopreservation: molecular detection and activation of angiogenesis after CAM-xenotransplantation

Background

Ovarian tissue cryopreservation has a wide range of cancerous indications. Avoiding relapse becomes a specific concern that clinicians frequently encounter. The data about the comparative viability of cancer cells after cryopreservation are limited. This study aimed to evaluate the effect of cryopreservation on breast cancer cells.

Methods

We used in-vitro cultured ZR-75-1 and MDA-MB-231 cell lines. Cell samples of each lineage were distributed into the non-intervened and cryopreserved groups. The cryopreservation procedures comprised programmed slow freezing followed by thawing at 100 °C, 60 s. Biological phenotypes and the related protein markers were compared between the two groups. The EVOS FL Auto 2 Cell Image System was used to monitor cell morphology. Cell proliferation, motility, and penetration were characterized by CCK-8, wound-healing, and transmembrane assay, respectively. The expression of Ki-67, P53, GATA3, E-cadherin, Vimentin, and F-Actin was captured by immunofluorescent staining and western blotting as the proxy measurements of the related properties. The chorioallantoic membrane (CAM) xenotransplantation was conducted to explore angiogenesis induced by cancer cells.

Results

After 5 days in vitro culture, the cell concentration of cryopreserved and non-intervened groups was 15.7 × 10⁴ vs. 14.4 × 10⁴cells/ml, (ZR-75-1, p > 0.05), and 25.1 × 10⁴ vs. 26.6 × 10⁴ cells/ml (MDA-MB-231, p > 0.05). Some cryopreserved ZR-75-1 cells presented spindle shape with filopodia and lamellipodia and dissociated from the cell cluster after cryopreservation. Both cell lines demonstrated increased cell migrating capability and invasion after cryopreservation. The expression of Ki-67 and P53 did not differ between the cryopreserved and non-intervened groups. E-cadherin and GATA3 expression downregulated in the cryopreserved ZR-75-1 cells. Vimentin and F-actin exhibited an upregulated level in cryopreserved ZR-75-1 and MDA-MB-231 cells. The cryopreserved MDA-MB-231 cells induced significant angiogenesis around the grafts on CAM with the vascular density 0.313 ± 0.03 and 0.342 ± 0.04, compared with that of non-intervened cells of 0.238 ± 0.05 and 0.244 ± 0.03, p < 0.0001.

Conclusions

Cryopreservation promotes breast cancer cells in terms of epithelial-mesenchymal transition and angiogenesis induction, thus increasing metastasis risk.

Long-term (24h) cooling of ovarian fragments in the presence of permeable cryoprotectants prior to freezing: Two unsuccesful IVF-cycles and spontaneous pregnancy with baby born after re-transplantation

Cancer is the second major cause of death in the world. The problem of post-cancer infertility plays a significant role, because chemotherapy can be gonadotoxic. Cryopreservation of ovarian tissue before cancer therapy with re-implantation after convalescence is the potential key solution to this problem. The aim of this study was to test the viability of cryopreserved human ovarian cortex after long-term cooling in culture medium composed of permeable cryoprotectants. Ovarian fragments from sixteen patients were randomly divided into two groups. After the operation, tissue pieces assigned to both groups were cooled to 5 °C for 22-24 h, frozen and thawed. Group 1 pieces (n = 32) were cooled before cryopreservation in the standard culture medium, and Group 2 pieces (n = 32) were cooled in the freezing medium (culture medium+6% ethylene glycol+6% dimethyl sulfoxide+0.15 M sucrose). Freezing was performed in standard 5 ml cryo-vials with ice formation at -9 °C, cooling from -9 to -34 °C at a rate of -0.3 °C/min and plunging at -34 °C into liquid nitrogen. After thawing in a 100 °C (boiling) water bath, the removal of cryoprotectants was performed in 0.5 M sucrose with 20 min exposure in sucrose and 30 min stepping rehydration. The effectiveness of the pre-freezing cooling of tissue was evaluated by the development of follicles (histology). Six months after the autotransplantation, oocytes from the twenty-seven-year old, hormonally stimulated patient were retrieved and fertilized with her partner sperm through the intracytoplasmic spermatozoa injection (ICSI). For groups 1 and 2, 93.5 ± 1.9% and 96.4 ± 2.0% of the preantral follicles, respectively, were morphologically normal (P > 0.1) (with a tendency toward increasing in quality in Group 2). Six months after the auto-transplantation, two ICSI cycles resulted in the gathering and transplantation of high quality embryos, but no pregnancy had been established. Thirteen months after the auto-transplantation, the patient became spontaneously pregnant and delivered a healthy baby girl at term. Long-term (24 h) cooling of ovarian tissue to 5 °C before cryopreservation in the presence of permeable cryoprotectants simplifies the protocol of cryopreservation and has a tendency of increasing of the cells viability after thawing.

Banking of human ovarian tissue potentially contaminated by cancer cells: experimental model for study of cryo-stability of these cells

Auto-transplantation of cryopreserved ovarian tissue for cancer survivors comes with the primary concern of the possible existence of cancer cells in the transplanting tissue. Lineal cancer cells are presented by industry in form of separated cells (suspensions). Data about experimental models for evaluation of a cryopreservation effect on viability of compacted lineal cancer cells is currently limited. This study aims to develop a suitable experimental model for cryobiological investigations of compacted cancer cells obtained after in vitro culture of a cell suspension. Suspended lineal breast cancer cells (ZR-75-1 and MDA-MB-231) were in vitro cultured in AIM V medium for formation of monolayer. Evaluation of the cell viability was performed by healing assay, transmembrane cell migration, invasion assay and immunofluorescent test of F-actin. It was established the possibility of formation of monolayer from viable cancer cells, scarification of monolayer of these cells and formation of compacted fragments. It is described also a behaviour of compacted cells during cryopreservation (saturation by permeable cryoprotectants, thawing and removal of cryoprotectants). The described method can be used for cryobiological investigations of lineal suspended cancer cells in compacted form as a model of tissues contaminated by malignant cells and solid tumors.

Nitrosative stress in human spermatozoa causes cell death characterized by induction of mitochondrial permeability transition-driven necrosis

Peroxynitrite is a highly reactive nitrogen species and a potent inducer of apoptosis and necrosis in somatic cells. Peroxynitrite-induced nitrosative stress has emerged as a major cause of impaired sperm function; however, its ability to trigger cell death has not been described in human spermatozoa. The objective here was to characterize biochemical and morphological features of cell death induced by peroxynitrite-mediated nitrosative stress in human spermatozoa. For this, spermatozoa were incubated with and without (untreated control) 3-morpholinosydnonimine (SIN-1), in order to generate peroxynitrite. Sperm viability, mitochondrial permeability transition (MPT), externalization of phosphatidylserine, DNA oxidation and fragmentation, caspase activation, tyrosine nitration, and sperm ultrastructure were analyzed. The results showed that at 24 h of incubation with SIN-1, the sperm viability was significantly reduced compared to untreated control (P < 0.001). Furthermore, the MPT was induced (P < 0.01) and increment in DNA oxidation (P < 0.01), DNA fragmentation (P < 0.01), tyrosine nitration (P < 0.0001) and ultrastructural damage were observed when compared to untreated control. Caspase activation was not evidenced, and although phosphatidylserine externalization increased compared to untreated control (P < 0.001), this process was observed in <10% of the cells and the gradual loss of viability was not characterized by an important increase in this parameter. In conclusion, peroxynitrite-mediated nitrosative stress induces the regulated variant of cell death known as MPT-driven necrosis in human spermatozoa. This study provides a new insight into the pathophysiology of nitrosative stress in human spermatozoa and opens up a new focus for developing specific therapeutic strategies to better preserve sperm viability or to avoid cell death.

Conventional freezing vs. cryoprotectant-free vitrification of epididymal (MESA) and testicular (TESE) spermatozoa: Three live births

Data of cryoprotectant-free vitrification of human testicular and epididymal spermatozoa are limited. The aim of this investigation was to compare two aseptic technologies of TESE (testicular) and MESA (epididymal) spermatozoa cryopreservation: standard conventional freezing with the use of cryoprotectants and cryoprotectant-free vitrification. Sperm motility, capacitation-like changes, acrosome reaction and the mitochondrial membrane potential of frozen (5% glycerol, -10 °C/min) and vitrified (Human Tubal Fluid + 1% Human Serum Albumin+0.25 M sucrose, plunging into liquid nitrogen of capillaries with spermatozoa isolated from liquid nitrogen (aseptic method) were compared. The quality of the cryoprotectant-free vitrified MESA- and TESE-spermatozoa was higher than that of spermatozoa conventionally frozen with permeable cryoprotectants. Intracellular sperm injection (ICSI) was performed with vitrified spermatozoa. We report the birth of three healthy babies from two women following ICSI with motile MESA- and TESE-spermatozoa vitrified without cryoprotectants. This is the first report of full-term pregnancies and babies born after ICSI with epididymal and testicular spermatozoa vitrified without cryoprotectants. In conclusion, cryoprotectant-free vitrification can be successfully applied for the cryopreservation of motile TESE- and MESA-spermatozoa.

A successful multidisciplinary approach for treatment and for preserving the reproductive potential in a rare case of acute lymphocytic leukemia during pregnancy

Leukemia in pregnancy is a rare condition with the prevalence of 1 in 75,000-100,000 pregnancies. In this case report, we present a successful multidisciplinary management strategy for treatment and for preserving the reproductive potential in a rare case of acute lymphocytic leukemia (ALL) during pregnancy. Several complex challenges existed and necessitated a multidisciplinary approach with strong coordination and collaboration between oncologists, gynecologists, reproductive cryobiologists, obstetricians, and neonatologists in order to improve the maternal and fetal outcome. Pregnancy in the second trimester is neither a contraindication for ALL treatment nor for emergency fertility preservation via ovarian tissue extraction and further cryopreservation.

An Experimental Model of Breast Cancer Cells: Informative Protocol for In Vitro Culture

BACKGROUND

Cryopreservation of ovarian tissue for patients with cancer comes with the concern for the existence of cancer cells in the grafts. Data about cancer cell viability after cryopreservation are currently lacking. For the experimental study of cryo-stability of cancer cells, different protocols of in vitro culture of various cell lines are used. The existing protocols are not able to mimic the effectiveness of in vivo/in situ development of cancer cells. This study aimed to test the new protocol for in vitro culture of breast cancer cells.

MATERIALS AND METHODS

ZR-75-1 and MDA-MB-231 cells were in vitro-cultured in standard [RPMI 1640 and Dulbecco's modified Eagle's medium (DMEM), respectively] and experimental (AIM V) medium. Cell phenotypes were tested by CCK-8 cell proliferation measurement, wound-healing assay, transmembrane cell migration and invasion assay and immunofluorescent staining. A 10-day in vitro culture without cell passaging was conducted on both cell lines in culture medium to observe the generation of a cell layer as a model of solid tumor tissue. The density of the cell layers was revealed by immunofluorescent staining.

RESULTS

AIM V significantly promoted continued proliferation of both cell lines. Cell motility of ZR-75-1 cells was increased considerably more in AIM V than in RPMI-1640. For MDA-MB-231 cells cultured in AIM V and DMEM, no significant differences in mobility and invasion were observed. Both cell lines maintained in AIM V medium generated a cell layer on day 7 and formed a compact structure on day 10 of in vitro culture.

CONCLUSION

In vitro culture of ZR-75-1 and MDA-MB-231 cells in AIM V medium is more informative than culture in standard medium. The described protocol provides a means for the formation of compact structures from in vitro-cultured cancer cells as a model of solid tumor tissue.

Cross border reproductive care (CBRC): a growing global phenomenon with multidimensional implications (a systematic and critical review)

PURPOSE

Many people travel abroad to access fertility treatments. This growing phenomenon is known as cross border reproductive care (CBRC) or fertility tourism. Due to its complex nature and implications worldwide, CBRC has become an emerging dilemma deserving more attention on the global healthcare agenda.

METHODS

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review of the literature was performed for all relevant full-text articles published in PubMed in English during the past 18 years to explore CBRC phenomenon in the new millennium.

RESULTS

Little is known about the accurate magnitude and scope of CBRC around the globe. In this systematic and critical review, we identify three major dimensions of CBRC: legal, economic, and ethical. We analyze each of these dimensions from clinical and practical perspectives.

CONCLUSION

CBRC is a growing reality worldwide with potential benefits and risks. Therefore, it is very crucial to regulate the global market of CBRC on legal, economic, and ethical bases in order to increase harmonization and reduce any forms of exploitation. Establishment of accurate international statistics and a global registry will help diminish the current information gap surrounding the CBRC phenomenon.

Comparison of the enzymatic efficiency of Liberase TM and tumor dissociation enzyme: effect on the viability of cells digested from fresh and cryopreserved human ovarian cortex

BACKGROUND

The aim of this study was to examine the effectiveness of Tumor Dissociation Enzyme (TDE) on the viability of follicles after digestion of fresh and cryopreserved ovarian cortex fragments (OCFs).

METHODS

Fresh and thawed OCF from 14 patients (29 ± 6 years), sized 20 to 210 mm³ were randomly distributed into four treatment groups and digested with 16% TDE or 0.05 mg/ml Liberase TM: Group 1, frozen OCF digested with TDE; Group 2, frozen OCF digested with LiberaseTM; Group 3, fresh OCF digested with TDE; and Group 4, fresh OCF digested with Liberase TM. Evaluation of follicle viability was performed under light microscope after staining with Neutral red. For visualization of viable and dead cells under a confocal laser scanning microscope, the follicles were stained with Calcein AM and ethidium homodimer-1.

RESULTS

The results showed that the number of retrieved follicles was significantly higher (990 vs 487; P < 0.01) in the TDE-treatment group compared to the Liberase TM-group. The presence of intense neutral red stained follicles was significantly higher in Group 1 and Group 3 compared to Group 2 and Group 4 (70.3% ± +/- 6.22 vs 53,1% ± 2.03 and 94.2% ± 6.6 vs 79.1% ± 2.1; P < 0.01). The percentage of Calcein AM stained follicles of class V1 was significantly higher in Group 1 and Group 3 compared to Group 2 and Group 4 (95.97% ± 7.8 vs 87.87% ± 2.4; 97.1% ± 6.8 vs 91.3% ± 2.3; P < 0.01).

CONCLUSION

The enzymatic digestion of ovarian cortex with TDE provides recovery of a higher number of healthy preantral follicles in contrast to earlier described Liberase TM procedure.

Advances in fertility preservation of female patients with hematological malignancies

INTRODUCTION

The most common forms of hematological malignancies that occur in female reproductive years are lymphoma and leukemia. Areas covered: Several aggressive gonadotoxic regimens such as alkylating chemotherapy and total body irradiation are used frequently in treatment of lymphoma and leukemia leading to subsequent iatrogenic premature ovarian failure and fertility loss. In such cases, female fertility preservation options should be offered in advance. Expert commentary: In order to preserve fertility of young women and girls with lymphoma and leukemia, several established, experimental, and debatable options can be offered before starting chemotherapy and radiotherapy. However, each of those female fertility preservation options has both advantages and disadvantages and may not be suitable for all patients. That is why a fertility preservation strategy should be individualized and tailored distinctively for each patient in order to be effective. Artificial human ovary is a novel experimental in vitro technology to produce mature oocytes that could be the safest option to preserve and restore fertility of young women and girls with hematological malignancies especially when other fertility preservation options are not feasible or contraindicated. Further research and studies are needed to improve the results of artificial human ovary and establish it in clinical practice.

Trehalose sustains a higher post-thaw sperm motility than sucrose in vitrified human sperm

One of the cryopreservation methods that best preserves sperm function is vitrification. However, comparative studies have not been performed to evaluate the effect of nonpermeable cryoprotectors on sperm function for prolonged periods of time post-devitrification. These times are necessary, especially in in vitro fertilisation and intrauterine insemination, for gamete interaction and then fertilisation to occur, while maintaining motility to arrive at the fertilisation site. In this study, sucrose (.25 m) and trehalose (.1 and .05 m) were compared in essential parameters like motility and plasma membrane integrity for 12 hr. Post-devitrification sperm motility using .1 m trehalose was 68.9%, higher than that obtained with .05 m trehalose (59.9%, p < .0081) and .25 m sucrose (57.9%, p < .0002). Similar results were obtained at 6 and 12 hr with .1 m trehalose (58.0% and 42.3% respectively) compared to .05 m trehalose (p < .0184 and p < .033) and .25 m sucrose (p < .0001 and p < .0012).There was no difference between .25 m sucrose and .05 m trehalose. Membrane integrity was best preserved at time 0 by .1 m trehalose (p < .05), but there was no significance at 6 and 12 hr compared to sucrose. Our results suggest that for assisted reproduction techniques that require motile spermatozoa for a longer period of time, use of .1 m trehalose is recommended in the sperm vitrification technique.

In Vitro Microvibration Increases Implantation Rate After Embryonic Cell Transplantation

In natural conditions the oocyte and embryo are subjected to ever-changing dynamic processes. However, the routine assisted reproductive technologies today involve the use of static in vitro culture systems. The objective was to determine whether there is any difference in the viability of embryos after in vitro culture under static and mechanical microvibration conditions. The viability of embryonic cells (9,624 embryos) generated from 4,436 couples after in vitro culture was evaluated. For groups ≤29, 30-34, 35-39, and ≥40 years, the following rates of high-quality embryos without fragmentation (two to four blastomeres on day 2; six to eight blastomeres and compacting morula on day 3; blastocyst, expanded and hatching blastocyst on day 5) were detected (static vs. vibration, respectively): 65% versus 71%, 44% versus 69%, 67% versus 76% (for statistically significant differences between respective rates in these three groups, p < 0.05), and 67% versus 66% (p > 0.1). The following baby-take-home rates were determined for groups ≤29, 30-34, 35-39, and ≥40 years (static vs. vibration, respectively): 30% versus 31% (p > 0.1, increasing only on the level of tendency), 28% versus 37%, 23% versus 29%, and 9% versus 15% (differences between respective rates in these three groups with p < 0.05). It was concluded that in vitro culture of embryos under microvibration (with a mimic of conditions in nature whereby oviductal fluid is mechanically agitated by the epithelial cilia) significantly increases the baby-take-home rate for patients 30 years and older.

Use of the fluorescent dye tetramethylrhodamine methyl ester perchlorate for mitochondrial membrane potential assessment in human spermatozoa

Mitochondrial membrane potential (ΔΨm) is an indicator of sperm quality and its evaluation complements the standard semen analysis. The fluorescent dye JC-1 has been widely used to assess sperm ΔΨm; however, some problems have been detected under certain experimental conditions. Another fluorescent compound, tetramethylrhodamine methyl ester perchlorate (TMRM), has been used in somatic cells and bovine spermatozoa but not in human spermatozoa. TMRM accumulates in hyperpolarised mitochondria and the fluorescence intensity of this compound correlates with ΔΨm. Thus, the aim of this study was to evaluate and validate the usefulness of the fluorescent dye TMRM for measuring sperm ΔΨm. The results showed that TMRM accurately detects sperm populations displaying either high or low ΔΨm. Moreover, TMRM was able to measure sperm ΔΨm under the experimental conditions in which JC-1 had previously presented difficulties. Differences in ΔΨm according to sperm and semen quality were properly detected and a positive correlation between ΔΨm and conventional semen parameters was observed. Finally, a positive correlation was found between the ΔΨm measurement by TMRM and by the widely used JC-1. In conclusion, TMRM is a simple, time-effective method, easy to set in laboratories equipped with flow cytometry technology, and can accurately detect changes in ΔΨm with efficiency comparable to JC-1 without its limitations.

Chapter 6 Technology of Aseptic Cryoprotectant-Free Vitrification of Human ICSI Spermatozoa

The aim of this chapter was to describe the standardized aseptic technology of permeable cryoprotectant-free vitrification of human spermatozoa in capillaries (for ICSI or IVF in microvolume). Spermatozoa, vitrified by this technology, are free from seminal plasma owing to swim-up procedure preceding vitrification and are free from permeable cryoprotectants. They are ready for further use immediately after warming without any additional treatment.

Cryopreservation and xenografting of human ovarian fragments: medulla decreases the phosphatidylserine translocation rate

BACKGROUND

Phosphatidylserine is the phospholipid component which plays a key role in cell cycle signaling, specifically in regards to necrosis and apoptosis. When a cell affected by some negative factors, phosphatidylserine is no longer restricted to the intracellular side of membrane and can be translocated to the extracellular surface of the cell. Cryopreservation can induce translocation of phosphatidylserine in response to hypoxia, increasing intracellular Ca²⁺, osmotic disruption of cellular membranes, generation of reactive oxygen species and lipid peroxidation. As such the aim of this study was to test the level of phosphatidylserine translocation in frozen human medulla-contained and medulla-free ovarian tissue fragments.

METHODS

Ovarian fragments from twelve patients were divided into small pieces of two types, medulla-free cortex (Group 1, n = 42, 1.5-3.0 × 1.5-3.0 × 0.5-0.8 mm) and cortex with medulla (Group 2, n = 42, 1.5-3.0 × 1.5-3.0 × 1.5-2.0 mm), pre-cooled after operative removal to 5 °C for 24 h and then conventionally frozen with 6 % dimethyl sulfoxide, 6 % ethylene glycol and 0.15 M sucrose in standard 5-ml cryo-vials. After thawing at +100 °C and step-wise removal of cryoprotectants in 0.5 M sucrose, ovarian pieces were xenografted to SCID mice for 45 days. The efficacy of tissues cryopreservation, taking into account the presence or absence of medulla, was evaluated by the development of follicles (histology with hematoxylin-eosin) and through the intensity of translocation of phosphatidylserine (FACS with FITC-Annexin V and Propidium Iodide).

RESULTS

For Groups 1 and 2, the mean densities of follicles per 1 mm³ were 9.8, and 9.0, respectively. In these groups, 90 and 90 % preantral follicles appeared morphologically normal. However, FACS analysis showed a significantly decreased intensity of translocation of phosphatidylserine (FITC-Annexin V positive) after cryopreservation of tissue with medulla (Group 2, 59.6 %), in contrast with tissue frozen without medulla (Group 1, 78.0 %, P < 0.05). In Groups 1 and 2 it was detected that 21.6 and 40.0 % cells were viable (FITC-Annexin V negative, Propidium Iodide negative).

CONCLUSION

The presence of medulla in ovarian pieces is beneficial for post-thaw development of cryopreserved human ovarian tissue.

Updates in preserving reproductive potential of prepubertal girls with cancer: Systematic review

INTRODUCTION

With increasing numbers of adult female survivors of childhood cancers due to advances in early diagnosis and treatment, the issue of preserving the reproductive potential of prepubertal girls undergoing gonadotoxic treatments has gained greater attention.

METHODS

According to PRISMA guidelines, a systematic review of the literature was performed for all relevant full-text articles published in PubMed in English throughout the past 15 years to explore the significant updates in preserving the reproductive potential of prepubertal girls with cancer.

RESULTS

The two established fertility preservation options, embryo freezing and egg freezing, cannot be offered routinely to prepubertal girls as these options necessitate prior ovarian stimulation and subsequent mature oocytes retrieval that are contraindicated or infeasible before puberty. Therefore, the most suitable fertility preservation options to prepubertal girls are (1) ovarian tissue freezing and autotransplantation, (2) in vitro maturation, and (3) ovarian protection techniques. In this review, we discuss in detail those options as well as their success rates, advantages, disadvantages and future directions. We also suggest a new integrated strategy to preserve the reproductive potential of prepubertal girls with cancer.

CONCLUSION

Although experimental, ovarian tissue slow freezing and orthotopic autotransplantation may be the most feasible option to preserve the reproductive potential of prepubertal girls with cancer. However, this technique has two major and serious disadvantages: (1) the risk of reintroducing malignant cells, and (2) the relatively short lifespan of ovarian tissue transplants. Several medical and ethical considerations should be taken into account before applying this technique to prepubertal girls with cancer.

Long-Time Cooling before Cryopreservation Decreased Translocation of Phosphatidylserine (Ptd-L-Ser) in Human Ovarian Tissue

Objectives

To translocation (externalization) of phosphatidylserine lead at least the five negative effects observed during cells cryopreservation: hypoxia, increasing of intracellular Ca²⁺, osmotic disruption of cellular membranes, generation of reactive oxygen species (ROS) and lipid peroxidation. The aim of this study was to test the intensiveness of the phosphatidylserine translocation immediately after thawing and after 45 d xenografting of human ovarian tissue, which was either frozen just after operative removal from patient or cooled before cryopreservation to 5°C for 24 h and then frozen.

Materials and Methods

Ovarian fragments from twelve patients were divided into small pieces in form of cortex with medulla, and randomly divided into the following four groups. Pieces of Group 1 (n=30) were frozen immediately after operation, thawed and just after thawing their quality was analyzed. Group 2 pieces (n=30) after operation were cooled to 5°C for 24 h, then frozen after 24 h pre-cooling to 5°C, thawed and just after thawing their quality was analyzed. Group 3 pieces (n=30) were frozen immediately after operation without pre-cooling, thawed, transplanted to SCID mice and then, after 45 d of culture their quality was analyzed. Group 4 pieces (n=30) were frozen after 24 h pre-cooling to 5°C, thawed, transplanted to SCID mice and then, after 45 d their quality was analyzed. The effectiveness of the pre-freezing cooling of tissuewas evaluated by the development of follicles (histology) and by intensiveness of translocation of phosphatidylserine (FACS with FITC-Annexin V and Propidium Iodide).

Results

For groups 1, 2, 3 and 4 the mean densities of follicles per 1 mm³ was 19.0, 20.2, 12.9, and 12.2, respectively (P_{1-2, 3-4} >0.1). For these groups, 99%, 98%, 88% and 90% preantral follicles, respectively were morphologically normal (P_{1-2, 3-4} >0.1). The FACS analysis showed significantly decreased intensiveness of translocation of phosphatidylserine after pre-cooling of frozen tissue (46.3% and 33.6% in Groups 2 and 4, respectively), in contrast with tissue frozen without pre-cooling (77.1% and 60.2 % in Groups 1 and 3, respectively, P_{1, 3-2, 4} <0.05).

Conclusions

Long time (24 h) cooling of ovarian tissue to 5°C before cryopreservation decreased translocation of phosphatidylserine that evidences about increases the viability of the cells in the tissue after thawing.

Effect of seminal plasma on Atlantic salmon (Salmo salar) sperm vitrification

This study was designed to test a vitrification method in Atlantic salmon spermatozoa and determine the capacity of seminal plasma (SP) to protect these cells from cryoinjuries. The vitrification medium consisted of a standard buffer for fish spermatozoa (Cortland medium) + 10% DMSO + 2% BSA + 0.13-M sucrose + SP at concentrations of 30% (G30), 40% (G40), or 50% (G50). Fresh sperm was used as a control. To freeze the samples, 30-μL suspensions of spermatozoa from each group were dropped directly into liquid nitrogen. The resulting spheres were placed in cryotubes for storage in liquid nitrogen. The cryotubes with the vitrified spermatozoa were thawed by placing them in a water bath at 37 °C for 45 seconds. After thawing, the following sperm quality parameters were determined by flow cytometry: DNA fragmentation (terminal deoxynucleotidyl transferase dUTP nick end labeling), plasma membrane integrity (SYBR-14/PI, staining technique), and mitochondrial membrane potential (JC-1 staining). An optical microscope was used to assess subjectively sperm motility, whereas fertility was determined by the presence of neurulation using five replicates per treatment in a sample of 30 eggs. Spermatozoa quality variables were preserved best when the highest concentration of SP (50%) was used (DNA fragmentation, 9.2%; plasma membrane integrity, 98.6%; mitochondrial membrane integrity, 47.2%; motility, 44.1%; and fertility, 46.2%).

Transplantation of cryopreserved human ovarian tissue: restoration of reproductive function after two cycles of radio- and chemo-therapeutic treatments

BACKGROUND

Patient S. was born in 1983, developed a Ewing-Sarcoma and obtained low dose chemotherapy in 1996. In 2007, Patient S. received high-dose chemotherapy because lung-metastases were diagnosed. The aim of the study was to investigate the health of cryopreserved ovarian tissue and also to examine whether this ovarian tissue can restore the reproductive function of patient after two cycles of radio-and chemo-therapeutic treatments.

METHODS

Twenty pieces of ovarian tissue (total of approximately 200 mm2) were conventionally frozen with 6% (v/v) dimethyl sulfoxide, 6% (v/v) ethylene glycol and 0.15 M sucrose and kept for five years before 8 pieces were thawed and transplanted back into the patient. Two small (1 x 2 x 1 mm) pieces of this thawed tissue were cultured in a chicken embryonic chorioallantoic membrane (CAM)-system for 5 days to assess the tissue viability.

RESULTS

The ovarian tissue that was grafted re-established spontaneous menstrual bleeding within five months and serum 17-beta estradiol increased from 19 to 330 pg/mL. Ultrasound revealed a dominant follicle at the site of the transplanted tissue in the follicular phase after the menstrual bleed. Analysis of the CAM cultured tissue established that 88% of the primordial follicles had degenerated and there was limited growth of blood vessels.

CONCLUSIONS

In spite of the damage caused by the cryopreservation the surviving follicles could restore ovarian function after re-transplantation.