Calcified matrix production by SAOS-2 cells inside a polyurethane porous scaffold, using a perfusion bioreactor

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Orthopedic Research

Background:

• Bone repair and regeneration present significant clinical challenges.
• While autografts are effective, they have associated complications.
• Novel biomaterials are needed as bone substitutes and scaffolds.

Purpose of the Study:

• To investigate the use of a hydrophobic cross-linked polyurethane scaffold for bone tissue engineering.
• To evaluate the effect of shear stress in a perfusion bioreactor on osteoblast behavior.
• To characterize the physical and mechanical properties of the polyurethane scaffold.

Main Methods:

• Fabrication of a porous polyurethane scaffold with an average pore diameter of 624 microm.
• Seeding and in vitro culturing of SAOS-2 human osteoblasts within the scaffold.
• Utilizing a perfusion bioreactor to apply controlled shear stress.
• Assessing cell proliferation, matrix production (osteopontin, osteocalcin, decorin, type I collagen), and calcium deposition.

Main Results:

• Perfusion at 3 mL/min significantly increased cell proliferation by 33% compared to static conditions.
• Substantial increases in osteopontin (9.16-fold), osteocalcin (71.9-fold), decorin (30.6-fold), and type I collagen (18.12-fold) secretion were observed.
• Calcium deposition increased by 10-fold under perfusion conditions.

Conclusions:

• The developed polyurethane scaffold supports osteoblast colonization and matrix deposition.
• Perfusion bioreactor culture enhances cellular activity and bone matrix formation.
• This engineered biomaterial shows promise as an osteoinductive implant for bone repair applications.