Development of novel platforms for the clinical applications of induced pluripotent stem cells
Notice bibliographique
Résumé
This thesis is aimed to develop applications of iPSCs for patients suffering from rare disorders. A personalised-platform was designed to match approved experimental drug/s to a patient with Leigh-like syndrome. It consisted of iPSCs and its derivatives (fibroblasts, neural stem cells, cardiomyocytes and forebrain neurons). Cell-type specific disease pathophysiologies of ATP, extracellular lactate, reactive oxygen species, mitochondrial-membrane-potential, growth and differentiation were assessed in comparison to control. All the cell-types were found to display significant errors in most of the parameters with multi-lineage differentiation, reactive oxygen species production and mitochondrial membrane potential observed to be severely affected. Proteomic analysis established the rescue of mitochondrial membrane potential and normalization of reactive oxygen species production as reproducible indicators of the drug candidates’ efficacy and toxicity. Systematic evaluation of the mitochondrial compromise proved suitability of Elamipretide, as the optimal drug for the studied variant. Next, we demonstrated isogenic sources for cell therapies for patients suffering with Mitochondrial disorders (MELAS and Kearns Sayre Syndrome) who displayed heteroplasmy of the mitochondrial DNA (mtDNA). Nucleated cells from blood displayed a high ratio of normal mtDNA to mutant mtDNA and thence were used to establish iPSCs and differentiated into multi-lineages (neural and cardiac) known to be affected in these disorders. The iPSCs and their derivatives didn’t show any mtDNA mutation over long term culture (>2 years). The patient iPSC-derived fibroblasts, neural stem cells and cardiomyocytes did not display any disease physiologies or progression in the parameters tested here - ATP, cellular growth, extracellular lactate, differentiation, electrophysiology, reactive oxygen species and mitochondrial membrane potential. The final chapter focussed on the immunological landscape of iPSCs and their derivatives, based on the dynamics of the major histocompatibility complexes (MHC-I and MHC-II). The surface expression of MHC-I was found to decrease and that of MHC-II was found to significantly increase after cardiac differentiation. Higher MHC-I led to immune evasion and higher MHC-II led to immune recognition. 26S proteasome was established to be a key regulator of both the MHC-surface-expression. Increasing the 26S proteasome activity in the iPSC-cardiomyocytes helped maintain higher MHC-I and lower MHC-II levels at the cell surface. This helped in conferring immunoprivilege to the iPSC-derived cardiomyocytes. Thus, in this body of work, I have presented novel clinical application of the iPSC – by developing a platform of iPSC-derived functional cell types to support precision medicine in patients with rare inborn disorders. I have also demonstrated that patients affected with mitochondrial disorders can benefit from iPSC generation from tissue with low levels of heteroplasmy, leading to isogenic cell therapy. In the end, I have attempted to address the major hurdle of immunogenicity in the clinical application of iPSC and their derivatives.
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 | 0,001 | 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 | 0,001 | 0,000 |
| Science ouverte | 0,000 | 0,001 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,003 | 0,001 |
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 ».