Similar phenotypes of cells in the repair tissues following microfracture or autologous chondrocyte implantation

Garcia, J.; Hulme, C.H.; Roberts, S.; Richardson, J.B.; Kuiper, J.H.; Wright, K.T

Abstract

Introduction

Autologous chondrocyte implantation (ACI) and microfracture are both used in the treatment of cartilage injuries. Previous findings suggest that the efficacy of these two therapies is similar in terms of short-term clinical outcome, however, the quality of repair tissue is thought to be better in ACI. This study aimed to compare the cells from within the repair tissue, several years post-treatment with either ACI or microfracture.

Materials and Methods

Cells were harvested from the repair tissue, removed during arthroplasty or arthrotomy, in patients who had previously had ACI (n = 3, knee or hip) or microfracture (n = 2, knee). Cells were cultured in monolayer up until passage 3, at which point RNA was extracted and the culture expanded cells were immunoprofiled via flow cytometry. The expression of important chondrogenic genes was assessed using semi-quantitative polymerase chain reaction. The doubling time was calculated for each of the cell populations.

Results

Cells from microfracture and ACI repair sites proliferated at similar rates (7 (±4.6) and 11(±8.8) days between passage (P) 1–2 and 8 (±6.6) and 4 (±0.9) days between P2-P3, respectively (P > 0.05). Immunoprofiling of the microfracture and ACI repair cells demonstrated that the repair cells were negative for CD19, CD34, CD45 and HLA-DR, positive for CD73, CD90 and CD105 and showed some CD14 positivity. There was no significant difference in the positivity for any of the CD markers between repair cells from microfracture or ACI treated defects (P > 0.05). Cells from repair tissue of both treatment groups did not express Collagen types II or X but expressed Collagen I, SOX9 and Aggrecan. There was no significant difference in the relative expression of any of the genes between repair cells (P > 0.05).

Discussion

These preliminary comparisons found no evidence for a difference in the growth kinetics, immunoprofile or the expression of key chondrogenic genes in cells derived from the repair tissue following microfracture or ACI in joints which have gone on to have further surgery. It must be noted, however, that the sample size was small and that culture expansion may alter the phenotype of the repair cells making them more similar over time.

Citation

Garcia, J., Hulme, C., Roberts, S., Richardson, J., Kuiper, J., & Wright, K. (2017). Similar phenotypes of cells in the repair tissues following microfracture or autologous chondrocyte implantation. International Journal of Experimental Pathology, 98(3), A23

• Journal Article Type: Conference Paper
• Online Publication Date: Aug 28, 2017
• Publication Date: 2017-06
• Deposit Date: Jun 12, 2023
• Journal: International Journal of Experimental Pathology
• Print ISSN: 0959-9673
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 98
• Issue: 3
• Pages: A23
• Publisher URL: https://onlinelibrary.wiley.com/doi/10.1111/iep.12235