24 TRANSGENESIS AND NUCLEAR TRANSFER USING STEM CELLS FROM CULTURED PORCINE PRIMORDIAL GERM CELLS
Notice bibliographique
Résumé
Embryonic germ (EG) cells are undifferentiated stem cells isolated from cultured primordial germ cells (PGC). These cells share many characteristics with embryonic stem cells including their morphology and pluripotency. Undifferentiated porcine EG cell lines demonstrating capacities of both in vitro and in vivo differentiation have been established (Shim H et al. 1997 Biol. Reprod. 57, 1089–1095). Since EG cells can be cultured indefinitely in an undifferentiated state, whereas somatic cells in primary culture are often unstable and have limited lifespan, EG cells may provide an inexhaustible source of karyoplasts in nuclear transfer (NT). This would be particularly advantageous in maintaining nuclear donor cells carrying a transgene. In addition, genome-wide demethylation of DNA occurs in pre-implantation embryos as well as PGC. Nuclear transfer embryos using EG cells rather than somatic cells may be close to embryos from normal fertilization in their DNA methylation status. If combined with NT technique, EG cells may potentially be useful for genetic manipulation in pigs. In this study the efficiencies of transgenesis and NT using porcine fetal fibroblast and EG cells were compared. Two different techniques were used to perform NT. When conventional NT procedure (Roslin method) involving fusion of donor cells with enucleated oocytes was used, the rates of development to the blastocyst stage were 16.8% (59/351) and 14.1% (50/354) in EG and somatic cell NT, respectively. In piezo-driven micromanipulation (Honolulu method) involving direct injection of donor nuclei into enucleated oocytes, the rates of blastocyst formation in EG and somatic cell NT were 11.9% (15/126) and 7.5% (12/160), respectively. Although the differences between EG and somatic cell NT were statistically insignificant, the rates of blastocyst development in EG cell NT were comparable to the somatic cell counterpart regardless of NT methods used in the present study. To investigate if EG cells can be used for transgenesis in pigs, GFP gene was introduced into porcine EG cells. Nuclear transfer embryos using transfected EG cells gave rise to blastocysts (29/137, 21.2%), and all embryos that developed to the blastocyst stage expressed GFP, based on observation under fluorescence microscope. In this study, the possibility of using EG cells as karyoplast donors in NT procedure was tested. The results suggest that EG cell NT may be used as an alternative to somatic cell NT, and transgenic pig embryos may be produced using EG cells. This research was supported by a grant (SC14033) from Stem Cell Research Center of the 21st Century Frontier Research Program funded by the Ministry of Science and Technology, Republic of Korea.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».