Study of chondrogenic potential of stem cells in co-culture with chondrons

Abstract

Objectives: Three-dimensional biomimetic scaffolds have widespread applications in biomedical tissue engineering due to similarity of their nanofibrous architecture to native extracellular matrix. Co-culture system has stimulatory effect on chondrogenesis of adult mesenchymal stem cells. This work presents a co-culture strategy using human articular chondrons and adipose-derived stem cells (ASCs) from infrapatellar fat pad (IPFP) for cartilage tissue production.

Materials and methods: Isolated stem cells were characterized by flowcytometry. Electrospun and polycaprolactone (PCL) scaffolds (900 nm fiber diameter) was obtained from Bon Yakhteh (Tehran-Iran) and human infrapatellar fat pad-derived stem cells (IPFP-ASCs) were seeded on them. IPFP-ASCs on scaffolds were co-cultured with articular chondrons using transwell. After 21 day, chondrogenic differentiation of stem cell was evaluated by determining the genes expression of collagen2, aggrecan and Indian hedgehog using real-time RT-PCR.

Results: Genes expression of collagen2, aggrecan by IPFP-ASCs did not alter significantly in comparison with control group. Howevers, expression of Indian hedgehog decreased significantly compared to control group (P< 0.05).

Conclusion: These findings indicate that chondrons obtained from osteoarthritic articular cartilage did not stimulate chondrogenic differentiation of IPFP-ASCs in co-culture.

Keywords: Chondron; Co-culture; Nanofiber; Poly-e-caprolactone scaffold.

Figure 1

Morphology of IPFP-ASCs in culture observed with an inverted phase-contrast microscope at different passages. The shape of cells changed during passages: p0 (A), p1 (B) and passage2 (C), 20X

Figure 2

Architecture of electrospun PCL nanofiber scaffold as seen with a scanning electron microscope at 4.00KX

Figure 3

Cells were tested against human antigens CD31, CD44, CD45, CD90. All experiments were conducted at passage 2

Figure 4

Morphology of cultured chondrons as seen with an inverted phase-contrast microscope during 15 day culture, 1^st day (A), 8^th day (B), 15^th day (C), 10X

Figure 5

IPFP-ASCs on PCL scaffold after 21 days, observed with inverted phase contrast microscope, 20X

Figure 6

Relative genes expression of chondrogenic cell/PCL and cell/PCL co-culture. Co-culture conditions decreased expression collagen2a1 (A), aggrecan (B) and IHH (C * = P< 0.05