Guiding morphogenesis in cell-instructive microgels for therapeutic angiogenesis.

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Vascular Biology

Background:

• Cell-based therapies require efficient delivery systems for improved therapeutic outcomes.
• Developing injectable platforms that guide cell organization is crucial for pro-angiogenic treatments.

Purpose of the Study:

• To design an injectable, biomaterial-guided cell delivery platform for therapeutic angiogenesis.
• To investigate the role of microgel properties and in vitro priming on cell assembly and vascularization.

Main Methods:

• Fabrication of functionalized alginate microgels with specific biochemical and biomechanical cues.
• Co-culture of mesenchymal stem cells and outgrowth endothelial cells (OEC) within microgels.
• In vitro priming of OECs under normoxia with growth factors to induce tubulogenesis.
• In vivo implantation in chick embryos to assess vascularization and host integration.

Main Results:

• Functionalized alginate microgels facilitated the co-assembly of stem cells and OECs into pre-vascularized microtissues.
• In vitro priming under normoxia and growth factors induced stable OEC tubulogenesis, resistant to ischemic conditions.
• Primed cells secreted pro-angiogenic factors and produced an extracellular matrix, creating a stable angiogenic niche.
• Implanted microgels promoted host-microtissue interaction, with detected human vascular structures and cell integration in vivo.

Conclusions:

• An integrated approach using pro-angiogenic cells, instructive microgels, and optimized in vitro priming shows promise for therapeutic angiogenesis.
• This injectable platform supports the formation of stable vascular networks and host integration, paving the way for advanced cell therapies.