Developing Implantable Scaffolds to Enhance Neural Stem Cell Therapy for Post-Operative Glioblastoma.

Area of Science:

• Biomedical Engineering
• Neuro-oncology
• Stem Cell Therapy

Background:

• Engineered tumoricidal neural stem cells (tNSCs) show promise for glioblastoma (GBM) treatment.
• Stabilizing tNSCs in the surgical cavity after GBM resection remains a significant challenge.
• Optimizing NSC delivery and persistence is crucial for effective post-surgical GBM therapy.

Purpose of the Study:

• To identify a polymeric scaffold that maximizes transplant, persistence, and tumor kill of tNSCs for post-surgical GBM.
• To evaluate scaffold-mediated delivery of tNSCs in mouse models of human GBM resection and recurrence.

Main Methods:

• Utilized a preclinical variant of the HB1.F3.CD neural stem cell line.
• Employed mouse models of human GBM resection/recurrence.
• Delivered tNSCs via direct injection, on poly-l-lactic acid scaffolds, and on gelatin matrices (GEMs).
• Assessed tNSC persistence using kinetic bioluminescence imaging.
• Engineered tNSCs to express thymidine kinase (tNSCs^tk) for prodrug therapy.

Main Results:

• Direct injection of tNSCs resulted in only 3-day persistence.
• Poly-l-lactic acid scaffolds extended tNSC persistence to 8 days; modifications did not improve this.
• GEMs extended tNSC persistence 8-fold compared to direct injection.
• tNSCs on GEMs migrated off scaffolds into tumor foci, exhibiting tumor-tropic homing.
• GEM/tNSCs^tk treatment reduced residual tumor volumes by 10-fold and extended median survival from 31 to 46 days in GBM xenografts.

Conclusions:

• Gelatin matrices (GEMs) significantly enhance the persistence and efficacy of engineered neural stem cell therapy for post-surgical glioblastoma.
• GEMs support tumor-tropic homing of tNSCs, improving their therapeutic potential.
• These findings provide design parameters for effective scaffold/tNSC composites, advancing tNSC therapy for human GBM trials.