5 Key Takeaways

• 1

  Researchers developed a 4-dimensional bio-Kirigami system combining a deformable, cell-laden hydrogel with a more rigid outer hydrogel ring.

• 2

  Human mesenchymal stem cell–laden constructs formed dome-shaped curvatures during 21 days of culture in both expansion and chondrogenic conditions.

• 3

  After removal of the outer ring, constructs cultured under chondrogenic conditions retained their dome shape for 6 days, whereas expansion-medium constructs gradually collapsed.

• 4

  Chondrogenic constructs had greater glycosaminoglycan content, stronger Alcian blue and type II collagen staining, and higher DNA content than controls.

• 5

  The study was limited by small cartilage-test samples, 6-day postremoval follow-up, and the absence of implantation or in vivo testing.