Culture of human ovarian tissue in xeno-free conditions using laminin components of the human ovarian extracellular matrix.

PURPOSE: Our purpose was to identify human ovarian extracellular matrix (ECM) components that would support in vitro culture of human ovarian tissue and be compatible with possible future clinical applications. We characterized ovarian expression of laminins and selected three laminin tripeptides for culture experiments to be compared with Matrigel, an undefined and animal-based mixture of ECM components. METHODS: Expression of the 12 laminin genes was determined on transcript and protein levels using cortical tissue samples (n = 6), commercial ovary RNA (n = 1), follicular fluid granulosa cells (n = 20), and single-cell RNA-sequencing data. Laminin 221 (LN221), LN521, LN511, and their mixture were chosen for a 7-day culture experiment along with Matrigel using tissue from 17 patients. At the end of the culture, follicles were evaluated by scoring and counting from serial tissue sections, apoptosis measured using in situ TUNEL assay, proliferation by Ki67 staining, and endocrine function by quantifying steroids in culture media using UPLC-MS/MS. RESULTS: Approximately half of the cells in ovarian cortex expressed at least one laminin gene. The overall most expressed laminin α-chains were LAMA2 and LAMA5, ß-chains LAMB1 and LAMB2, and γ-chain LAMC1. In culture experiments, LN221 enhanced follicular survival compared with Matrigel (p < 0.001), whereas tissue cultured on LN521 had higher proportion of secondary follicles (p < 0.001). LN511 and mixture of laminins did not support the cultures leading to lower follicle densities and higher apoptosis. All cultures produced steroids and contained proliferating cells. CONCLUSIONS: LN221 and LN521 show promise in providing xeno-free growth substrates for human ovarian tissue cultures, which may help in further development of folliculogenesis in vitro for clinical practices. The system could also be used for identification of adverse effects of chemicals in ovaries.

NANOG priming before full reprogramming may generate germ cell tumours.

Reprogramming somatic cells into a pluripotent state brings patient-tailored, ethical controversy-free cellular therapy closer to reality. However, stem cells and cancer cells share many common characteristics; therefore, it is crucial to be able to discriminate between them. We generated two induced pluripotent stem cell (iPSC) lines, with NANOG pre-transduction followed by OCT3/4, SOX2, and LIN28 overexpression. One of the cell lines, CHiPS W, showed normal pluripotent stem cell characteristics, while the other, CHiPS A, though expressing pluripotency markers, failed to differentiate and gave rise to germ cell-like tumours in vivo. Comparative genomic hybridisation analysis of the generated iPS lines revealed that they were genetically more stable than human embryonic stem cell counterparts. This analysis proved to be predictive for the differentiation potential of analysed cells. Moreover, the CHiPS A line expressed a lower ratio of p53/p21 when compared to CHiPS W. NANOG pre-induction followed by OCT3/4, SOX2, MYC, and KLF4 induction resulted in the same tumour-inducing phenotype. These results underline the importance of a re-examination of the role of NANOG during reprogramming. Moreover, this reprogramming method may provide insights into primordial cell tumour formation and cancer stem cell transformation.

Genetic predictors of controlled ovarian hyperstimulation: where do we stand today?

BACKGROUND: Nowadays, the use of IVF has improved the prospects of infertility treatment. The expected outcome of IVF depends greatly on the effectiveness of controlled ovarian hyperstimulation (COH), where exogenous gonadotrophins are used to induce folliculogenesis. The response to stimulation varies substantially among women and is difficult to predict. Several predictive markers of COH outcome have been proposed (e.g. maternal age and ovarian reserve), but the search for optimal predictors is ongoing. Pharmacogenetic studies demonstrate the effects of individual genetic variability on COH outcome and the potential for customizing therapy based on the patient's genome. METHODS: MEDLINE, EMBASE, DARE, CINAHL and the Cochrane Library, and references from relevant articles were investigated up to February 2011 regarding any common genetic variation and COH/IVF outcome. RESULTS: Several polymorphisms in genes involved in FSH signalling, estrogen biosynthesis, folliculogenesis, folate metabolism and other aspects influence the response to exogenous gonadotrophin administration, resulting in differences in COH and IVF outcomes. Nevertheless, the most studied polymorphism FSHR Asn680Ser is practically the only genetic marker, together with ESR1 PvuII T/C, that could be applied in clinical tests. CONCLUSIONS: Although data are accumulating with evidence suggesting that the ovarian response to COH is mediated by various polymorphisms, the optimal biomarkers and the efficacy of the tests still remain to be evaluated.

Markers of pluripotency and differentiation in human neural precursor cells derived from embryonic stem cells and CNS tissue.

Cell transplantation therapies for central nervous system (CNS) deficits such as spinal cord injury (SCI) have been shown to be effective in several animal models. One cell type that has been transplanted is neural precursor cells (NPCs), for which there are several possible sources. We have studied NPCs derived from human embryonic stem cells (hESCs) and human fetal CNS tissue (hfNPCs), cultured as neurospheres, and the expression of pluripotency and neural genes during neural induction and in vitro differentiation. mRNA for the pluripotency markers Nanog, Oct-4, Gdf3, and DNMT3b were downregulated during neural differentiation of hESCs. mRNA for these markers was found in nonpluripotent hfNPC at higher levels compared to hESC-NPCs. However, Oct-4 protein was found in hESC-NPCs after 8 weeks of culture, but not in hfNPCs. Similarly, SSEA-4 and CD326 were only found in hESC-NPCs. NPCs from both sources differentiated as expected to cells with typical features of neurons and astrocytes. The expressions of neuronal markers in hESC-NPCs were affected by the composition of cell culture medium, while this did not affect hfNPCs. Transplantation of hESC-NPC or hfNPC neurospheres into immunodeficient mouse testis or subcutaneous tissue did not result in tumor formation. In contrast, typical teratomas appeared in all animals after transplantation of hESC-NPCs to injured or noninjured spinal cords of immunodeficient rats. Our data show that transplantation to the subcutaneous tissue or the testes of immunodeficient mice is not a reliable method for evaluation of the tumor risk of remaining pluripotent cells in grafts.

Current achievements and future research directions in ovarian tissue culture, in vitro follicle development and transplantation: implications for fertility preservation.

BACKGROUND Female cancer patients are offered 'banking' of gametes before starting fertility-threatening cancer therapy. Transplants of fresh and frozen ovarian tissue between healthy fertile and infertile women have demonstrated the utility of the tissue banked for restoration of endocrine and fertility function. Additional methods, like follicle culture and isolated follicle transplantation, are in development. METHODS Specialist reproductive medicine scientists and clinicians with complementary expertise in ovarian tissue culture and transplantation presented relevant published literature in their field of expertise and also unpublished promising data for discussion. As the major aims were to identify the current gaps prohibiting advancement, to share technical experience and to orient new research, contributors were allowed to provide their opinioned expert views on future research. RESULTS Normal healthy children have been born in cancer survivors after orthotopic transplantation of their cryopreserved ovarian tissue. Longevity of the graft might be optimized by using new vitrification techniques and by promoting rapid revascularization of the graft. For the in vitro culture of follicles, a successive battery of culture methods including the use of defined media, growth factors and three-dimensional extracellular matrix support might overcome growth arrest of the follicles. Molecular methods and immunoassay can evaluate stage of maturation and guide adequate differentiation. Large animals, including non-human primates, are essential working models. CONCLUSIONS Experiments on ovarian tissue from non-human primate models and from consenting fertile and infertile patients benefit from a multidisciplinary approach. The new discipline of oncofertility requires professionalization, multidisciplinarity and mobilization of funding for basic and translational research.

Genetic stability of human embryonic stem cells: A first-step toward the development of potential hESC-based systems for modeling childhood leukemia.

Human ESCs provide an opportunity for modeling human-specific strategies to study the earliest events leading to normal hematopoietic specification versus leukemic transformation. Of interest, are the human childhood acute leukemias harboring specific fusion oncogenes such as MLL-AF4, TEL-AML1 or BCR-ABL wherein clinically significant manifestations arise in utero. The mechanisms of transformation are not amenable to analysis with patient samples and, many mouse models for pediatric leukemias have fallen short in illuminating the human disease because they do not recapitulate key aspects of the actual disease, suggesting that the mouse models are missing essential components of oncogenesis present in the human embryo. Prior to using hESCs as a tentative system for modeling leukemia, robust studies aimed at demonstrating their genetic stability are required; otherwise, cooperating mutations already present could prime hESCs susceptible to transformation. We performed an extensive molecular cytogenetic and cellular in vitro and in vivo analysis which reveals an overall genomic stability of HS181 and HS293 hESCs maintained long-term by mechanical dissociation in human feeders. Importantly, we show for the first time that the genetically stable HS181 hESC line differentiates into CD45+ hematopoietic cells and clonogenic hematopoietic progenitors. This data should encourage stem cell researchers to implement robust cytogenetic tools when assessing hESC genetic stability, in order to detect tiny but relevant biological functional or structural chromosome abnormalities and, paves the way for generating fusion oncogene-expressing transgenic hESCs as a human-specific system for studying the early in utero events leading to normal hematopoietic specification versus childhood leukemic transformation.

Novel cryopreservation method for dissociated human embryonic stem cells in the presence of a ROCK inhibitor.

BACKGROUND: Human embryonic stem cells (hESCs) have potential use in clinical therapy and regenerative medicine. One of the major challenges regarding the application of these cells is the development of an efficient cryopreservation protocol, since current methods, which include slow-freezing-rapid thawing and vitrification of colonies in suspension, present poor viability and high differentiation rates. Dissociated hESC suspensions do not survive cryopreservation because they are susceptible to apoptosis upon cell detachment and dissociation. A selective Rho-associated kinase (ROCK) inhibitor has been reported to increase the survival of dissociated hESCs and their cloning efficiency. METHODS AND RESULTS: Here, we describe a novel method for dissociated hESCs cryopreservation in the presence of the ROCK inhibitor Y-27632. The addition of this inhibitor to the freezing and post-thawing medium significantly increased the survival rate and efficiency of colony formation. Moreover, the hESC colonies obtained after the cryopreservation in the presence of the ROCK inhibitor showed a very low rate of differentiation and a reduced time of recovery. After prolonged culture of frozen-thawed dissociated hESCs, the characteristic properties of pluripotent cells were observed, including normal karyotype, morphological features, marker expression (SSEA-4, TRA-1-60, TRA-1-81 and Oct-4) and the potential to differentiate into derivatives of all three germ layers after embryoid bodies formation. CONCLUSION: This novel method for the cryopreservation of dissociated hESCs may reduce the time required to amplify frozen stocks, and facilitate not only the storage of large numbers of hESCs but also the widespread use of these cells in regenerative medicine.

Gonadotrophin stimulation of non-luteinized granulosa cells increases steroid production and the expression of enzymes involved in estrogen and progesterone synthesis.

BACKGROUND: In regular IVF treatment, mature oocytes are collected with their luteinized granulosa cells (GCs). When in vitro maturation (IVM) of the oocytes is performed, non-luteinized GCs can be collected. We have investigated how these cells respond to gonadotrophin stimulation in culture. METHODS: GCs were collected from patients undergoing IVM treatment and compared with GCs from IVF patients. The cells were stimulated with FSH and/or hCG. After 48 h, culture media were collected for hormone analysis, and RNA was isolated for gene expression analysis. RESULTS: In IVM GCs, hCG and FSH alone and in combination induced significantly increased progesterone production, and FSH alone and in combination with hCG increased estrogen production. We also studied the gene expression of P-450aromatase and P-450scc and the receptors for FSH and LH. In non-luteinized GCs, the expression levels of P-450aromatase increased with all treatments, and P-450scc expression increased with the combined FSH and hCG treatment. LHR expression increased with FSH treatment, but the FSH receptor expression did not change with different treatments. CONCLUSIONS: Non-luteinized GCs behaved differently from luteinized GCs in culture. The data help understand the final stages of maturation of human oocytes and follicles.

Cost-effective approaches to in vitro fertilization: means to improve access.

Many childless couples would like to have access to in vitro fertilization (IVF) through public-sector programs, but such programs are scant because of the high costs that IVF entails today. A solution for health departments worldwide might be to leave IVF methods requiring expensive equipment and ovarian stimulating hormones - such as human recombinant gonadotropins, plus gonadotropin-releasing hormone analogues to prevent a surge of luteinizing hormone - to the private sector. Rather, health departments could focus on methods using less equipment and no ovarian stimulating agent at all if possible. If not possible, inexpensive clomiphene citrate could be used, combined with human menopausal gonadotropin if needed. Before embryo transfer, oocyte maturation could occur in vitro or in a makeshift incubator: a tube closed, wrapped, and left in the woman's vagina for 24 h. To prevent short- and long-term costs as well as possible lifelong problems, the transfer of multiple embryos should not be performed.

Anti-Müllerian hormone inhibits initiation of growth of human primordial ovarian follicles in vitro.

BACKGROUND: Anti-Müllerian hormone (AMH) inhibits the initiation of the development and early growth of mouse ovarian follicles. Furthermore, the ovarian follicle pool diminishes prematurely in AMH-knockout mice. In this study, we examined whether AMH plays a similar role in humans, controlling ovarian follicle growth. METHODS: Human ovarian cortical tissue biopsy specimens were cut into small pieces and cultured for 7 days in medium containing rat recombinant AMH at 0, 10, 30 or 100 ng/ml. The developmental stages and viability of the follicles were evaluated from histological sections. RESULTS: Similar to previous studies, significant initiation of follicle growth was observed in almost all culture media, as demonstrated by a significantly smaller proportion of primordial follicles (14-26%) compared with non-cultured control tissue (56%). The exception was tissue in medium supplemented with AMH at 100 ng/ml. Here, the proportion of primordial follicles was not significantly different from that in non-cultured tissue; furthermore, it was significantly greater than that in vehicle control cultures and cultures containing AMH at 10 ng/ml, indicating the inhibition of growth initiation. Viability was unaffected by the presence of AMH when compared with tissues in control media. CONCLUSIONS: Recombinant AMH at a concentration of 100 ng/ml has an inhibitory effect on early human ovarian follicular development in vitro, suppressing the initiation of primordial follicle growth.

Mutational analysis of the human SLC26A8 gene: exclusion as a candidate for male infertility due to primary spermatogenic failure.

SLC26A8 is an anion transporter that is solely expressed in the testes. It interacts with MgcRacGAP that shows strong structural similarity with the Drosophila protein RotundRacGAP, which is established to have an essential role for male fertility in the fruit fly. To explore whether the SLC26A8 gene has a role in human male infertility, we performed mutational analysis in the coding region of the SLC26A8 gene in 83 male infertility patients and two groups of controls using single-strand conformational polymorphism and direct sequencing methods. We found six novel coding sequence variations, of which five lead to amino acid substitutions. All variants were found with similar frequencies in both patients and controls, thus suggesting that none of them may be causally associated with infertility. We conclude that the SLC26A8 mutations are not a common cause of male infertility.

Concomitant abuse of anabolic androgenic steroids and human chorionic gonadotrophin impairs spermatogenesis in power athletes.

Abuse of anabolic androgenic steroids (AASs) may be an aetiological factor in male infertility among recreational power athletes. They try to avoid AAS-induced deterioration in spermatogenesis by combining doses of human chorionic gonadotrophin (HCG) and/or antiestrogens with their AAS abuse. Eighteen healthy male power athletes using massive doses of AASs were recruited for the study. Semen samples were collected during AAS abuse and 1.5 and 6 months after cessation of the abuse. They were also asked about their reproductive activity six years after the study. At the end of the AAS cycle, the sperm count was 33 +/- 49 x 10 (6) /ml (mean +/- SD), and only one subject had azoospermia. At 1.5 months after cessation of the AAS cycles, the mean sperm concentration was 30 +/- 42 x 10 (6) /ml, and after six months 77 +/- 70 x 10 (6) /ml. There were significant differences between the sample drawn six months after cessation of AAS abuse and both samples drawn during and 1.5 months after the abuse (p

Comparative genomic hybridization and karyotyping of human embryonic stem cells reveals the occurrence of an isodicentric X chromosome after long-term cultivation.

Human embryonic stem (hES) cells are important research tools in studies of the physiology of early tissue differentiation. In addition, prospects are high regarding the use of these cells for successful cell transplantation. However, one concern has been that cultivation of these cells over many passages might induce chromosomal changes. It is thus important to investigate these cell lines, and check that a normal chromosomal content is retained even during long-term in vitro culture. Comparative genomic hybridization (CGH) was used to analyse three hES cell lines derived in our laboratory and cultured continuously for 30-42 weeks, comprising 35-39 cell passages. CGH could be successfully performed in 48 out of a total of 50 isolated single cells (96%). All three lines (HS181, HS235 and HS237) were shown to have a normal chromosomal content when analysed by both single cell CGH and by karyotyping up to passages 39, 39 and 35 respectively. No aneuploidies or larger deletions or amplifications were detected, and they were female (46,XX). However, HS237 was reanalysed at passage 61, and at that point an aberrant X chromosome was detected by karyotyping. The aberration was confirmed and characterized by single cell CGH and fluorescence in situ hybridization analysis, 46,X,idic(X)(q21). Thus, chromosomal aberrations may occur over time in stem cell lines, and continuous analysis of these cells during cultivation is crucial. Single cell CGH is a method that can be used for continuous analysis of the hES cell lines during cultivation, in order to detect chromosome imbalance.

Real-time reverse transcription-polymerase chain reaction analysis of translation initiation factor 1A (eIF-1A) in human and mouse preimplantation embryos.

Fluorescence-monitored real-time reverse transcription-polymerase chain reaction (RT-PCR) was used to study steady state concentrations of translation initiation factor eIF-1A mRNA in mouse and human preimplantation embryos. Its expression in human embryos has not been described previously. Human oocytes, and 2-cell and 4-cell embryos all showed comparable total concentrations of eIF-1A RNA, indicating a gradual decrease in the average concentration per blastomere during these developmental stages. A 4-fold increase was observed in the 8-cell embryos. This concentration remained at the morula stage, followed by a 7- to 8-fold further increase at the blastocyst stage. Mouse preimplantation embryos already showed increased concentrations of eIF-1A RNA at the 2-cell stage. Thus, transcription levels of the eIF-1A gene are associated with embryonic gene activation (EGA) in both species. The method used, real time RT-PCR, proved to be sensitive enough to detect quantitative expression in single mouse blastomeres, the observed values for steady-state concentrations of mRNA in single blastomeres correlating well with the values for whole embryos. The possibility to study gene expression quantitatively in single blastomeres may be useful in preimplantation genetic diagnosis.

Single cell CGH analysis reveals a high degree of mosaicism in human embryos from patients with balanced structural chromosome aberrations.

We have performed comparative genomic hybridization (CGH) analysis of single blastomeres from human preimplantation embryos of patients undergoing preimplantation genetic diagnosis (PGD) for inherited structural chromosome aberrations and from embryos of IVF couples without known chromosomal aberrations. The aim was to verify the PGD results for the specific translocation, reveal the overall genetic balance in each cell and visualize the degree of mosaicism regarding all the chromosomes within the embryo. We successfully analysed 94 blastomeres from 28 human embryos generated from 13 couples. The single cell CGH could verify most of the unbalanced translocations detected by PGD. Some of the embryos exhibited a mosaic pattern regarding the chromosomes involved in the translocation, and different segregation could be seen within an embryo. In addition to the translocations, we found a high degree of numerical aberrations including monosomies, trisomies and duplications or deletions of parts of chromosomes. All of the embryos (100%) were mosaic, containing more than one chromosomally uniform cell line, or even chaotic with a different chromosomal content in each blastomere.

Percutaneous cutting needle biopsies for histopathological assessment and sperm retrieval in men with azoospermia.

BACKGROUND: Twenty-three men (45 testes) with azoospermia underwent percutaneous testicular biopsy under local anaesthesia. METHODS: In all but one of the 45 testes two biopsies were taken close to each other, one with a 16 gauge (n = 44) and another with a 14 gauge (n = 45) cutting needle, both with a 19 mm notch. Three quarters of the tissue was used for histopathological assessment and one quarter for direct microscopy. RESULTS: The histopathological findings were similar between the two needles. The observations with direct microscopy corresponded with the histopathological assessments concerning the presence of mature spermatids in 41 of 45 (91%) biopsies using the 14 gauge and in 40 of 44 (91%) biopsies using the 16 gauge needle. There were no post-operative complications except for minimal pain and minor local swelling. CONCLUSIONS: Percutaneous material retrieved using 16 gauge and 14 gauge needles is sufficient for histopathological assessment, and the two needles are equally reliable for testicular sperm retrieval. However, needle biopsy with one puncture may not be representative of the entire testis.

Clinical outcome of treatment cycles using preimplantation genetic diagnosis for structural chromosomal abnormalities.

OBJECTIVES: To explore oocyte recovery, embryo quality, the number of transferable embryos and pregnancy rate after preimplantation genetic diagnosis (PGD) in patients with structural chromosomal aberrations. METHODS: PGD was performed in seven couples with Robertsonian translocations (Rob), eight couples with reciprocal translocations (Rec), two couples with inversions and one couple with a deletion. A total of 43 treatment cycles were carried out. RESULTS: A total of 14.2 oocytes per cycle were retrieved. Fertilisation and cleavage rates were 63% and 58%, respectively. Of the biopsied embryos 20% were transferable. Comparison of the Rob and Rec group revealed no significant differences in number of oocytes, fertilisation or cleavage rates. The number of transferable embryos after biopsy was significantly higher in the Rob group than in the Rec group. When embryo transfer (ET) was performed the pregnancy rate did not differ between the Rob and the Rec groups. Twenty-eight embryo transfers (one or two embryos) were carried out leading to eight clinical pregnancies (29% per ET): two twins, four singletons, one miscarriage and one ectopic pregnancy. All the children are carriers of balanced chromosomal aberrations. CONCLUSION: An acceptable pregnancy rate can be achieved among couples with structural chromosomal abnormalities.

[Ethical aspects of stem cell research. Legislation and guidelines in Europe]. / Etiska aspekter på stamcellsforskning. Lagar och riktlinjer i Europa.

Research on different types of stem cells is of major interest because of its apparent very promising therapeutic prospects, such as for Parkinson's and Alzheimer's disease, spinal cord injuries, stroke, diabetes, cardiac failure, liver failure, cartilage injuries, severe blood diseases, cancer etc. Stem cells can be derived from different sources: adult tissue, foetal tissues, and from in vitro fertilised embryos. Depending on their origin they have varying capacity to multiply and differentiate to other cell types. It is at present not possible to predict which types of cells will be best suitable for various therapeutic situations. Embryonic stem cells have been shown capable of differentiating into all the different tissues and cell types of the body, but they cannot form a new individual. Because of the ethics question involved, The European Group on Ethics on Science and New Technologies for the European Commission and Parliament (EGE), and the Ethics Committee of the Nordic Council of Ministers have prepared reports and given guidelines for research on stem cells. According to the guidelines, every country should regulate the research. Only embryos, which cannot be used in infertility treatment, and have been donated for research, can be used. Creation of embryos solely for research purposes, including somatic cell nuclear transfer, is not regarded as acceptable for the time being. Both partners of the donating couple have to sign an informed consent document. Ongoing research in Sweden is well in line with these European and Nordic recommendations.