A photopatternable multiplex GelMA platform for studying small EV-brain endothelial interactions and direction-resolved glioblastoma spheroid outgrowth.

Authors

Seyed Nasir Hosseini Karimi, Nadin Bedikyan, Muhammet Atay Özten, Ceren Unal, Ebru Celik, Ferdi Oguz, Melike Kocahasan, Emel Sokullu

Published in

Biomaterials science. Oct 30, 2026. Epub Oct 30, 2026.

Abstract

Gelatin methacryloyl (GelMA) photopatterning enables spatial tumour-endothelial cultures, but formulation selection and imaging readouts must account for endothelial responses and heterogeneous tumour outgrowth. Four GelMA/Irgacure 2959 formulations (3 or 5% w/v polymer; 0.5 or 1% w/v photoinitiator) were screened using freeze-dried scanning electron microscopy, hydrated rheology, metabolic activity and expression of five endothelial-associated genes. The 3% GelMA/0.5% photoinitiator formulation (Gel3PI0.5) yielded the highest mean biological readouts in brain microvascular endothelial cells (BMECs). An ordered array of U87-containing microconstructs was photopatterned using this formulation and assembled onto a separately prepared BMEC-laden compartment. Endothelial marker retention and area-normalised impedance characterised the resulting static construct. A small extracellular-vesicle (EV) fraction isolated directly from human amniotic fluid was evaluated by bulk quantitative polymerase chain reaction and sector-based imaging. Two complementary descriptors quantified the 90th percentile distance of U87-positive pixels from the aggregate centre (P90) and their area occupancy within a 500 µm radius (C₅₀₀). At Day 8, 50 µg mL^-1 EV-associated protein increased P90 relative to untreated BMEC-free cultures without a resolved C₅₀₀ difference; in BMEC-containing cultures, 75 versus 25 µg mL^-1 increased C₅₀₀ without a resolved P90 difference. Thus, radial extent and local occupancy captured different condition-associated outgrowth features. Within the 5% polymer pair, lower initiator loading improved mean metabolic activity without a corresponding decrease in representative storage modulus, supporting biological criteria for material selection. The unmatched doses across endothelial contexts support within-arm and predefined-condition comparisons; they do not isolate an endothelial-by-EV interaction or establish functional blood-brain barrier behaviour.

PMID:
42961069
Bibliographic data and abstract were imported from PubMed on 30 Oct 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.