INVESTIGATION OF A NOVEL MICROCAPSULE MEMBRANE INTEGRATING POLYETHYLENE GLYCOL TO ALGINATE, POLY-L-LYSINE AND CHITOSAN MICROCAPSULES FOR THE APPLICATION OF LIVER CELL TRANSPLANTATION
Notice bibliographique
Résumé
P668 Aims: Liver transplantation is the main form of therapy for most liver diseases. A major drawback to transplantation is the lack of donors and continuous requirement of immunosuppressants. Microencapsulation is an emerging technology which can be used to entrap isolated hepatocytes for cell transplanation as an alternative treatment to several liver diseases. One of the limiting factors in the progress of such therapy is attaining a biocompatible polymer enabling the long-term entrapment and growth of the hepatocytes without causing adverse host immune responses. Presently the most commonly studied membranes are the alginate-poly-l-lysine-alginate (APA) and alginate-chitosan (AC) microcapsules, however there remain limitations associated with these membranes. In the current study, improvements to the biocompatibility and stability of these membranes are investigated by the addition of a polyethylene glycol (PEG) coating and the potential of a novel membrane combining alginate, poly-l-lysine, chitosan and PEG is studied with the objective of proposing a membrane most suitable for cell entrapment. Methods: Five different microcapsules were prepared including APA, APA with PEG, AC, AC with PEG and the novel alginate-chitosan-PEG-PLL-alginate (ACPPA) microcapsule. Mechanical strength of the capsules were assessed using an osmotic pressure test and a rotational stress test. A fluorescence reader (FLx800) was used to detect permeability of dextran through the membranes. Morphological studies on capsule integrity in serum was observed microscopically. Cytotoxicity tests were perfomed by encapsulating Human HepG2 cells and performing an MTT calorimetric assay for monitroing metabolic activity. Further studies on immuno protection using macrophages and cryopreservation potential are also to be investigated. Results: Microcapsules of approximately 400+/-30μm were prepared. Stability tests, using osmotic pressure techniques, reveal the addition of PEG resulted in an increase in mechanical stability of both APA and AC capsules by over 50%. The rotational stress test indicate the novel membrane formulation to exhibit mechanical strength similar to APA membranes and greater than the AC, ACPEG and APPEG microcapsules. The ACPPA membrane was found to retain integrity in FBS. Cytotoxicity tests using human HepG2 cells indicate low viability of AC membranes however, positive MTT was observed for the remaining 4 membranes studied which implies that the addition of PEG can support cellular growth. Conclusions: Results support previous studies which indicate PEG may improve biocompatibility of polymers. The integration of PEG to microcapsules enhances mechanical strength and supports the proliferation of liver cells. This study confirms that the novel membrane combining PLL, chitosan and PEG shows similar mechanical properties as APA capsules. As previous studies indicate that APA encapsulated cells can result in cell growth and protein adhesion to the membrane surface, the new membrane may be an alternative biomaterial for microencapsulation cell therapy.
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 machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| 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 | 0,001 | 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 source (Gemma direct ou Codex distillé), 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 ».