Teratoma mesentérico maduro en una mujer adulta: reporte de caso y revisión de la literatura / Mature mesenteric teratoma in an adult women: Case report and literature

Introducción. Los teratomas son neoplasias que surgen a partir de células germinales pluripotenciales y derivan de dos o más capas de células. Se clasifican en tumores maduros, que contienen tejidos bien diferenciados, o inmaduros, que contienen estructuras inmaduras y embrionarias. Su localización más frecuente son las gónadas; la ubicación mesentérica es infrecuente y se han descrito aproximadamente 40 casos en la literatura mundial. Dentro del abordaje diagnóstico y terapéutico, se emplea la tomografía computarizada y la resonancia magnética nuclear para caracterizar la lesión, evaluar la extensión intraabdominal y la relación con otras estructuras. El diagnóstico debe confirmarse mediante el examen histopatológico. Caso clínico. Paciente femenina de 56 años, con antecedente de carcinoma ductal infiltrante de mama izquierda en remisión, en estudios de seguimiento con hallazgo incidental en tomografía de abdomen de lesión abdominopélvica dependiente del mesenterio, contornos lisos y nivel grasa-líquido. Estudios de extensión con marcadores tumorales negativos. Resultados. Por la alta sospecha clínica e imagenológica de teratoma, fue llevada a resección quirúrgica de la lesión. El examen histopatológico confirmó el diagnóstico de teratoma quístico maduro del mesenterio. Conclusión. El teratoma mesentérico es una entidad clínica rara, que debe ser considerado como uno de los diagnósticos diferenciales de una masa abdominal con efecto compresivo. El diagnóstico se basa principalmente en el examen clínico y los hallazgos imagenológicos. La escisión quirúrgica temprana es el pilar del tratamiento; el abordaje laparoscópico o abierto depende de las características clínicas y la experiencia del cirujano.

Background. Teratomas are neoplasms that arise from pluripotent germ cells, derived from two or more layers of germ cells. They are classified as mature tumors (cystic or solid), which contain well-differentiated tissues, or as immature tumors, which contain immature and embryonic structures. Its most frequent location is the female and male gonads; the mesenteric location is rare and approximately 40 cases have been described in the world literature. Within the diagnostic and therapeutic approach, computed tomography and magnetic resonance imaging are used to characterize the lesion, assess intra-abdominal extension and the relationship with other structures. The diagnosis must be confirmed by histopathological examination. Clinical case. A 56-year-old female patient with a history of infiltrating ductal carcinoma of the left breast in remission. In follow-up studies, incidental abdominal tomography finding of an abdominopelvic lesion dependent on the mesentery at the level of the mesogastrium, smooth contours with fat-liquid level. Extension studies with negative tumor markers. Results. Due to high clinical and imaging suspicion of teratoma, the patient was taken to resection of the lesion. Histopathological examination confirmed the diagnosis of mature cystic teratoma of the mesentery. Conclusion. Mesenteric teratoma is a rare clinical entity and is considered one of the differential diagnoses of an abdominal mass with a compressive effect. Diagnosis is mainly based on clinical examination and imaging findings. Early surgical excision is the mainstay of treatment; laparoscopic or open approach depends on the clinical characteristics and the experience of the surgeon.

Presentación atípica de teratoma quístico maduro gigante en una paciente adolescente: a propósito de un caso / Atypical presentation of a giant mature cystic teratoma in an adolescent patient: A case report

Introducción: El teratoma quístico maduro es un tipo de tumor derivado de las células germinales que aparece en pacientes en edad fértil. La edad más frecuente de aparición de este tipo de tumores es entre los 20 y40 años.Caso clínico: Se presenta el caso de una paciente adolescente de 18 años con masa abdominal gigante de crecimiento abrupto cuya presentación fue atípica dado el tamaño de esta, el cual se manifestó con dolor abdominal agudo.Tratamiento: Se realiza resección de la masa la cual confirma el diagnóstico histopatológico de teratoma quístico maduro.Conclusión: Este tipo de patologías rara vez se presentan con un crecimiento tan exagerado como el caso de la paciente en mención, y la resolución quirúrgica sigue siendo el gold estándar en cuanto al tratamiento.Palabras clave:DeCS: Teratoma, Células germinativas embrionarias, Adolescente, Neoplasias

Introduction: Mature cystic teratoma is a type of tumor derived from germ cells that appears in patients of childbearing age. The most common age at which this type of tumor appearsis 20 to40.Clinical case: The case of an 18-year-old adolescent patient with a giant abdominal mass of abrupt growth is presented, whose presentation was atypical given its size, which manifested with acute abdominal pain Treatment: Amass resection confirmedthehistopathological diagnosis of mature cystic ter-atoma.Conclusion: This type of pathology rarely presents with growth as exaggerated as in the case of the patient mentioned. Surgicalresolution continues to be the gold standard in terms of treatment

Asynchronous embryonic germ cell development leads to a heterogeneity of postnatal ovarian follicle activation and may influence the timing of puberty onset in mice.

BACKGROUND: Ovarian follicles, which are the basic units of female reproduction, are composed of oocytes and surrounding somatic (pre) granulosa cells (GCs). A recent study revealed that signaling in somatic preGCs controlled the activation (initial recruitment) of follicles in the adult ovaries, but it is also known that there are two waves of follicle with age-related heterogeneity in their developmental dynamics in mammals. Although this heterogeneity was proposed to be crucial for female reproduction, our understanding of how it arises and its significance is still elusive. RESULTS: In the current study, by deleting the key secreted factor KIT ligand from preGCs and analyzing the follicle cell developmental dynamics, we revealed distinct patterns of activation and growth associated with the two waves of follicles in mouse ovary. Our results confirmed that activation of adult wave follicles is initiated by somatic preGCs and dependent on the KIT ligand. By contrast, activation of first wave follicles, which are awakened from germ cells before follicle formation, can occur in the absence of preGC-secreted KIT ligand in postnatal ovaries and appears to be oocyte-initiated. We also found that the asynchronous activity of phosphatidylinositol 3 kinases (PI3K) signaling and meiotic process in embryonic germ cells lead to the follicle heterogeneity in postnatal ovaries. In addition, we supplied evidence that the time sequence of embryonic germ cell development and its related first wave follicle growth are correlated to the time of puberty onset in females. CONCLUSION: Taken together, our study provides evidence that asynchronous development of embryonic oocytes leads to the heterogeneity of postnatal ovarian follicle activation and development, and affects the timing of onset of puberty in females.

Expanding homogeneous culture of human primordial germ cell-like cells maintaining germline features without serum or feeder layers.

In vitro expansion of human primordial germ cell-like cells (hPGCLCs), a pluripotent stem cell-derived PGC model, has proved challenging due to rapid loss of primordial germ cell (PGC)-like identity and limited cell survival/proliferation. Here, we describe long-term culture hPGCLCs (LTC-hPGCLCs), which actively proliferate in a serum-free, feeder-free condition without apparent limit as highly homogeneous diploid cell populations maintaining transcriptomic and epigenomic characteristics of hPGCLCs. Histone proteomics confirmed reduced H3K9me2 and increased H3K27me3 marks in LTC-hPGCLCs compared with induced pluripotent stem cells (iPSCs). LTC-hPGCLCs established from multiple human iPSC clones of both sexes were telomerase positive, senescence-free cells readily passaged with minimal cell death or deviation from the PGC-like identity. LTC-hPGCLCs are capable of differentiating to DAZL-positive M-spermatogonia-like cells in the xenogeneic reconstituted testis (xrTestis) organ culture milieu as well as efficiently producing fully pluripotent embryonic germ cell-like cells in the presence of stem cell factor and fibroblast growth factor 2. Thus, LTC-hPGCLCs provide convenient access to unlimited amounts of high-quality and homogeneous hPGCLCs.

Mouse Primordial Germ Cells: In Vitro Culture and Conversion to Pluripotent Stem Cell Lines.

Primordial germ cells (PGCs) are the embryonic precursors of the gametes. Despite decades of research, in vitro culture of PGCs remains a major challenge and has previously relied on undefined components such as serum and feeders. Notably, PGCs cultured for extended periods do not maintain their lineage identity but instead undergo conversion to form pluripotent stem cell lines called embryonic germ (EG) cells in response to LIF/STAT3 signaling. Here we report both established and new methodologies to derive EG cells, in a range of different conditions. We show that basic fibroblast growth factor is not required for EG cell conversion. We detail the steps taken in our laboratory to systematically remove complex components and establish a fully defined protocol that allows efficient conversion of isolated PGCs to pluripotent EG cells. In addition, we demonstrate that PGCs can adhere and proliferate in culture without the support of feeder cells or serum. This may well suggest novel approaches to establishing short-term culture of PGCs in defined conditions.

Chromatin Profiling in Mouse Embryonic Germ Cells by CUT&RUN.

Cleavage under targets and release using nuclease (CUT&RUN) allows the chromatin profiling of proteins of interest for which specific antibodies are available. Because it is performed on intact chromatin in situ, CUT&RUN provides exceptional signal over background, making it an ideal choice for chromatin profiling on primary cells available at limited numbers. Here, we describe its application to the profiling of histone post-translational modifications in germ cells isolated from mouse embryos from 12.5 up to 18.5 days postfertilization. This approach can be applied to as low as 100 isolated germ cells, allowing the generation of multiple genome-wide profiles from the cells obtained from a single embryo.

Transplantation of human embryonic stem cell-derived retinal pigment epithelial cells (MA09-hRPE) in macular degeneration.

The use of human embryonic stem cell (hESC)-derived Retinal Pigment Epithelium (RPE) transplants has advanced dramatically in different forms for clinical application in macular degeneration. This review focuses on the first generation of hESC-RPE cell line, named as "MA09-hRPE" by Astellas Institute of Regenerative Medicine (AIRM), and its therapeutic application in human, which evaluated the safety and efficacy of MA09-hRPE cell line transplanted in patients with macular degeneration. This project marks the first milestone in overcoming ethical hurdles and oncogenic safety concerns associated with the use of an embryonic stem cell-derived line. Through in-depth, evidence-based analysis of the MA09-hRPE cell line, along with other hESC-RPE cell lines, this review aims to draw attention to the key technical challenges pertinent to the generation of a biologically competent hESC-RPE cell line and distill the four key prognostic factors residing in the host retina, which concurrently determine the outcomes of clinical efficacy and visual benefits. Given that the technology is still at its infancy for human use, a new clinical regulatory path could aid in cell line validation through small cohort, adaptive clinical trials to accelerate product development toward commercialization. These strategic insights will be invaluable to help both academia and industry, collaboratively shorten the steep learning curve, and reduce large development expenditures spent on unnecessary lengthy clinical trials.

Retinoic acid signaling in regulation of meiosis during embryonic development in mice.

In the embryonic gonads of mice, the genetic and epigenetic regulatory programs for germ cell sex specification and meiosis induction or suppression are intertwined. The quest for garnering comprehensive understanding of these programs has led to the emergence of retinoic acid (RA) as an important extrinsic factor, which regulates initiation of meiosis in female fetal germ cells that have attained a permissive epigenetic ground state. In contrast, germ cells in fetal testis are protected from the exposure to RA due to the activity of CYP26B1, an RA metabolizing enzyme, which is highly expressed in fetal testis. In this review, we provide an overview of the molecular mechanisms operating in fetal gonads of mice, which enable regulation of meiosis via RA signaling.

FGF2 Signaling Plays an Important Role in Maintaining Pluripotent State of Pig Embryonic Germ Cells.

Germ cells are alternative sources for deriving pluripotent stem cells. Because embryonic germ cells (EGCs) possess physiological and developmental features similar to those of embryonic stem cells, pig EGCs are considered a potential tool for generating transgenic animals for agricultural usage. Therefore, in this study, we attempted to establish and characterize pig EGCs from fetal gonads. EGC lines were derived from the genital ridges of porcine fetuses in media containing leukemia inhibitory factor (LIF), fibroblast growth factor 2 (FGF2), and stem cell factor. After establishment, these cells were cultured and stabilized in LIF- or FGF2-containing media. The cell lines were maintained under both conditions over an extended time period and spontaneously differentiated into the three germ layers in vitro. Interestingly, expression of pluripotency markers showed different patterns between cell lines cultured in LIF or FGF2. SSEA4 was only expressed in FGF2-treated pig EGCs (FGF2-pEGCs), not LIF-treated pig EGCs (LIF-pEGCs). Pluripotency genes were upregulated in FGF2-pEGCs, and germline markers were highly expressed, indicating that FGF2 supplements are more efficient in supporting the pluripotency of pEGCs. In conclusion, we verified that FGF2 signaling plays an important role in reprogramming and maintaining pEGCs from fetal gonads.

DUSP9 Modulates DNA Hypomethylation in Female Mouse Pluripotent Stem Cells.

Blastocyst-derived embryonic stem cells (ESCs) and gonad-derived embryonic germ cells (EGCs) represent two classic types of pluripotent cell lines, yet their molecular equivalence remains incompletely understood. Here, we compare genome-wide methylation patterns between isogenic ESC and EGC lines to define epigenetic similarities and differences. Surprisingly, we find that sex rather than cell type drives methylation patterns in ESCs and EGCs. Cell fusion experiments further reveal that the ratio of X chromosomes to autosomes dictates methylation levels, with female hybrids being hypomethylated and male hybrids being hypermethylated. We show that the X-linked MAPK phosphatase DUSP9 is upregulated in female compared to male ESCs, and its heterozygous loss in female ESCs leads to male-like methylation levels. However, male and female blastocysts are similarly hypomethylated, indicating that sex-specific methylation differences arise in culture. Collectively, our data demonstrate the epigenetic similarity of sex-matched ESCs and EGCs and identify DUSP9 as a regulator of female-specific hypomethylation.

Is there a place for human fetal-derived stem cells for cell replacement therapy in Huntington's disease?

Huntington's disease (HD) is a neurodegenerative disease that offers an excellent paradigm for cell replacement therapy because of the associated relatively focal cell loss in the striatum. The predominant cells lost in this condition are striatal medium spiny neurons (MSNs). Transplantation of developing MSNs taken from the fetal brain has provided proof of concept that donor MSNs can survive, integrate and bring about a degree of functional recovery in both pre-clinical studies and in a limited number of clinical trials. The scarcity of human fetal tissue, and the logistics of coordinating collection and dissection of tissue with neurosurgical procedures makes the use of fetal tissue for this purpose both complex and limiting. Alternative donor cell sources which are expandable in culture prior to transplantation are currently being sought. Two potential donor cell sources which have received most attention recently are embryonic stem (ES) cells and adult induced pluripotent stem (iPS) cells, both of which can be directed to MSN-like fates, although achieving a genuine MSN fate has proven to be difficult. All potential donor sources have challenges in terms of their clinical application for regenerative medicine, and thus it is important to continue exploring a wide variety of expandable cells. In this review we discuss two less well-reported potential donor cell sources; embryonic germ (EG) cells and fetal neural precursors (FNPs), both are which are fetal-derived and have some properties that could make them useful for regenerative medicine applications.

bFGF signaling-mediated reprogramming of porcine primordial germ cells.

Primordial germ cells (PGCs) have the ability to be reprogrammed into embryonic germ cells (EGCs) in vitro and are an alternative source of embryonic stem cells. Other than for the mouse, the systematic characterization of mammalian PGCs is still lacking, especially the process by which PGCs convert to pluripotency. This hampers the understanding of germ cell development and the derivation of authenticated EGCs from other species. We observed the morphological development of the genital ridge from Bama miniature pigs and found primary sexual differentiation in the E28 porcine embryo, coinciding with Blimp1 nuclear exclusion in PGCs. To explore molecular events involved in porcine PGC reprogramming, transcriptome data of porcine EGCs and fetal fibroblasts (FFs) were assembled and 1169 differentially expressed genes were used for Gene Ontology analysis. These genes were significantly enriched in cell-surface receptor-linked signal transduction, in agreement with the activation of LIF/Stat3 signaling and FGF signaling during the derivation of porcine EG-like cells. Using a growth-factor-defined culture system, we explored the effects of bFGF on the process and found that bFGF not only functioned at the very beginning of PGC dedifferentiation by impeding Blimp1 nuclear expression via a PI3K/AKT-dependent pathway but also maintained the viability of cultured PGCs thereafter. These results provide further insights into the development of germ cells from livestock and the mechanism of porcine PGC reprogramming.

Discs large 5, an Essential Gene in Drosophila, Regulates Egg Chamber Organization.

Discs large 5 (Dlg5) is a member of the MAGUK family of proteins that typically serve as molecular scaffolds and mediate signaling complex formation and localization. In vertebrates, Dlg5 has been shown to be responsible for polarization of neural progenitors and to associate with Rab11-positive vesicles in epithelial cells. In Drosophila, however, the function of Dlg5 is not well-documented. We have identified dlg5 as an essential gene that shows embryonic lethality. dlg5 embryos display partial loss of primordial germ cells (PGCs) during gonad coalescence between stages 12 and 15 of embryogenesis. Loss of Dlg5 in germline and somatic stem cells in the ovary results in the depletion of both cell lineages. Reduced expression of Dlg5 in the follicle cells of the ovary leads to a number of distinct phenotypes, including defects in egg chamber budding, stalk cell overgrowth, and ectopic polar cell induction. Interestingly, loss of Dlg5 in follicle cells results in abnormal distribution of a critical component of cell adhesion, E-cadherin, shown to be essential for proper organization of egg chambers.

Pluripotent stem cells derived from mouse primordial germ cells by small molecule compounds.

Primordial germ cells (PGCs) can give rise to pluripotent stem cells known as embryonic germ cells (EGCs) when cultured with basic fibroblast growth factor (bFGF), stem cell factor (SCF), and leukemia inhibitory factor. Somatic cells can give rise to induced pluripotent stem cells (iPSCs) by introduction of the reprogramming transcription factors Oct4, Sox2, and Klf4. The effects of Sox2 and Klf4 on somatic cell reprogramming can be reproduced using the small molecule compounds, transforming growth factor-ß receptor (TGFßR) inhibitor and Kempaullone, respectively. Here we examined the effects of TGFßR inhibitor and Kempaullone on EGC derivation from PGCs. Treatment of PGCs with TGFßR inhibitor and/or Kempaullone generated pluripotent stem cells under standard embryonic stem cell (ESC) culture conditions without bFGF and SCF, which we termed induced EGCs (iEGCs). The derivation efficiency of iEGCs was dependent on the differentiation stage and sex. DNA methylation levels of imprinted genes in iEGCs were reduced, with the exception of the H19 gene. The promoters of genes involved in germline development were generally hypomethylated in PGCs, but three germline genes showed comparable DNA methylation levels among iEGs, ESCs, and iPSCs. These results show that PGCs can be reprogrammed into pluripotent state using small molecule compounds, and that DNA methylation of these germline genes is not maintained in iEGCs.

Generation of chimeric piglets by injection of embryonic germ cells from inbred Wuzhishan miniature pigs into blastocysts.

BACKGROUND: Human embryonic stem/germ (ES/EG) cell research poses ethical dilemma, it is therefore critical to establish alternative sources of cells for relevant studies. Considering the similarities between the inbred miniature Wuzhishan pigs (WZSP) and humans, ES/EG from these pigs can serve as potential substitutes in human research. In this study, we reported our results that successfully established stable EG cell lines from the WZSP. METHODS: Primordial germ cells (PGCs) were isolated from the genital ridges of pig fetuses at 25 to 28 days of pregnancy. To obtain stable EG cell line, PGCs were maintained on STO cells in DMEM containing multiple essential growth factors. RESULTS: Two EG cell lines were established and characterized by positive alkaline phosphatase staining (AKP), expressions of Oct-4, SSEA-1, SSEA-3, SSEA-4, ability to differentiate into cells of all three germ layers in vitro, and generation of chimeric offsprings after microinjection and embryo transfer. Transmission electron microscopy demonstrated that the cytoplasmic structure of pig EG cells were rather simple and had a higher nuclear-to-cytoplasm ratio. Scanning electron microscopy showed the sizes of pig EG cells were similar to mouse EG cells. Both EG cell lines showed normal karyotypes. The EG cells were propagated for more than 20 passages and underwent multiple cycles of freezing and thawing, without losing their pluripotency (as distinguished by AKP staining). CONCLUSIONS: Both in vitro and in vivo evidence strongly demonstrated that EG cells harvested from the inbred miniature WZSP were pluripotent and can be used for relevant pig or human studies.

Derivation of putative porcine embryonic germ cells and analysis of their multi-lineage differentiation potential.

Embryonic germ (EG) cells are cultured pluripotent stem cells derived from the primordial germ cells (PGCs) that migrate from the dorsal mesentery of the hindgut to the developing genital ridge. In this study, the morphology of the porcine genital ridge was assessed in embryos harvested on days 22-30 of pregnancy. PGCs from embryos at these stages were cultured to obtain porcine EG cell lines, and EG-like cells were derived from PGCs from embryos harvested on days 24-28 of pregnancy. The EG-like cells expressed Oct4, Sox2, Nanog, SSEA-3, SSEA-4 and alkaline phosphatase (AP). These cells were able to form embryoid bodies (EBs) in suspension culture and differentiate into cells representative of the three germ layers as verified by a-fetoprotein (AFP), α-smooth muscle actin (α-SMA), and Nestin expression. Spontaneous differentiation from the porcine EG-like cells of delayed passage in vitro showed that they could differentiate into epithelial-like cells, mesenchymal-like cells and neuron-like cells. In vitro directed differentiation generated osteocytes, adipocytes and a variety of neural lineage cells, as demonstrated by alizarin red staining, oil red O staining, and immunofluorescence for neuronal class Ⅲ ß-tubulin (Tuj1), glial fibrillary protein (GFAP) and galactosylceramidase (GALC), respectively. These results indicate that porcine EG-like cells have the potential for multi-lineage differentiation and are useful for basic porcine stem cell research.

The mammalian germline as a pluripotency cycle.

Naive pluripotency refers to the capacity of single cells in regulative embryos to engender all somatic and germline cell types. Only germ cells - conventionally considered to be unipotent - can naturally re-acquire pluripotency, by cycling through fertilisation. Furthermore, primordial germ cells express, and appear to be functionally dependent upon, transcription factors that characterise the pluripotent state. We hypothesise that germ cells require pluripotency factors to control a de-restricted epigenome. Consequently, they harbour latent potential, as manifested in teratocarcinogenesis or direct conversion into pluripotent stem cells in vitro. Thus, we suggest that there exists an unbroken cycle of pluripotency, naive in the early epiblast and latent in the germline, that is sustained by a shared transcription factor network.

PDGF mediates derivation of human embryonic germ cells.

Human embryonic germ cells (hEGCs) are a valuable and underutilized source of pluripotent stem cells. Unlike embryonic stem cells, which have been extensively studied, little is known about the factors that regulate hEGC derivation and maintenance. This study demonstrates for the first time a central role for selective activation of PDGFR signaling in the derivation and maintenance of pluripotency in hEGCs. In the study, hEGCs were found to express PDGF receptor α at high levels compared to human embryonic stem cells (hESCs). PDGF significantly improved formation of alkaline phosphatase (AP) positive hEGC colonies. We subsequently determined that PDGF activates the phosphatidylinositol-3-kinase (PI3K) pathway as phosphorylation of AKT was up-regulated in response to PDGF. Furthermore, inhibition of PI3K signaling using small molecular inhibitor LY294002 led to significantly decreased AP positive hEGC colony formation whereas inhibition of MAPK pathway using U0126 had a negligible effect. We established a primary mechanism for PDGF mediated derivation and maintenance of hEGCs by demonstrating that OCT4 was upregulated and PTEN was suppressed in a dose dependent manner in response to PDGF.

Isolation,cultivation and identification of human embryonic fibroblasts and expressions of cytokines essential for growth of human embryonic germ cells in vitro / 吉林大学学报(医学版)

Objective To isolate,cultivate and identify the human embryonic fibroblasts(hEFs) derived from the gonadal ridges and dorsal mesenteries of human embryos,and to detect the expression by hEFs of cytokines crucial for the growth of human embryonic germ cells(hEG) in vitro.Methods The hEFs were isolated by enzyme digestion from gonadal ridges and dorsal mesenteries of 5-to 9-week old human embryos.The cells were then cultivated.The biologic characteristics(morphology,growth characteristics and cell cycle) of these cells were also studied.The reverse transcription-polymerase chain reaction(RT-PCR) was used to seek the expressions of a specific fibroblast marker,prolyl 4-hydroxylase ?,and a specific marker of epithelial cells,cytokeratin-4,in the cells.The expressions of cytokines essential for the growth of hEG,namely basic fibroblast growth factor(bFGF) and leukemia inhibitory factor(LIF),were also examined by RT-PCR.Results The hEFs were successfully isolated and cultivated from gonadal ridges and dorsal mesenteries of human embryos.They could be passaged beyond the 25th generation.The biologic characteristics of the cells did not change,even in high-passage cells or frozen-thawed cells.The cells expressed prolyl 4-hydroxylase ?, but not cytokeratin-4,which was similar to the fibroblasts.The cultured cells expressed bFGF and LIF.Conclusion The hEFs derived from gonadal ridges and dorsal mesenteries of human embryos are successfully isolated and cultivated,and the cells express the cytokines essential for the growth of hEG in vitro.

Isolation,culture and primary identification of human primordial germ cells / 第三军医大学学报

Objective To explore how to isolate and culture human primordial germ cells(PGCs).Methods Human embryonic fibroblasts(HEFs) isolated from embryos at 2 to 3 months of age received a radiation of 60Co ?-ray and then served as feeder layer cells.Cells collected from trypsinized human embryonic gonadal ridges and dorsal mesenteries(5 to 9 weeks post-fertilization) were cultured on HEF feeder layers in the medium with recombinant human leukemia inhibitory factor(LIF),recombinant human basic fibroblast growth factor(bFGF) and forskolin.Histochemical and immunocytochemical assays were used to identify the stage specific embryonic antigen-1and 4(SSEA-1/4) of the cultured cells.Reverse transcription polymerase chain reaction(RT-PCR) was used to identify the expressions of specific genes,including Oct-4,Ifitm-3,stella,Mvh and DAZL.Embryonic bodies were cultured as while.Results The collected cells were growing on the feeder layer and formed a typical nestlike multicellular colonies.The cells showed diploid chromosome in karyotype analysis and expressed SSEA-1/4 and specific genes,Oct-4,Ifitm-3,stella,Mvh and DAZL,indicating that the cells were PGCs.When cultured in hanging drop,the PGCs developed into embryonic bodies,showing multipotential ability.Conclusion Human PGCs can be isolated from genital ridges and dorsal mesenteries of embryos and cultured in vitro on HEF feeder layer.The formation of the embryonic stem cell colony can be observed,and the cells cultured by this method is confirmed to be embryonic germ cells.