Repair Mechanism of Osteochondral Defect Promoted by Bioengineered Chondrocyte Sheet

Abstract

Cell sheet engineering has developed as a remarkable method for cell transplantation. In the field of cartilage regeneration, several studies previously reported that cartilage defects could be regenerated by transplantation of a chondrocyte sheet using cell sheet engineering. However, it remains unclear how such a thin cell sheet could repair a deep cartilage defect. We, therefore, focused on the mechanism of cartilage repair using cell sheet engineering in this study. Chondrocyte sheets and synovial cell sheets were fabricated using cell sheet engineering, and these allogenic cell sheets were transplanted to cover an osteochondral defect in a rat model. Macroscopic and histological evaluation was performed at 4 and 12 weeks after transplantation. Analysis of the gene expression of each cell sheet and of the regenerated tissue at 1 week after transplantation was performed. In addition, green fluorescent protein (GFP) transgenic rats were used as donors (transplanted chondrocyte sheets) or recipients (osteochondral defect models) to identify the cell origin of regenerated cartilage.Cartilage repair was significantly better in the group implanted with a chondrocyte sheet than in that with a synovial cell sheet. The results of gene expression analysis suggest that the possible factor contributing to cartilage repair might be TGFb1. Cell tracking experiments using GFP transgenic rats showed that the regenerated cartilage was largely composed of cells derived from the transplanted chondrocyte sheets.

A Physiology-Inspired Multifactorial Toolbox in Soft-to-Hard Musculoskeletal Interface Tissue Engineering

“…Among different biochemical factors, oxygen is a crucial molecule and we will discuss the influence of oxygen tension on cellular behavior. Additionally, small molecules, like ascorbic acid, can be employed to accelerate ECM deposition, particularly for cell sheet engineering [56][57][58][59], or to promote cellular proliferation in cell expansion protocols (e.g., glucose and essential amino acids).…”

Control of Cell Adhesion and Detachment on a Nanostructured Scaffold Composed of a Light-responsive Gas Generation film

“…11 µl of gas was generated in 90 s from a 6-mm-diameter area of this nanoscaffold, and the increase in gas volume was approximately linear, meaning that the gas-generation rate was 0.1 µl/s from 0-90 s. When cells adhere to the scaffold, the distance between the cells and the scaffold is within 1 mm. For example, the volume of cells and nanoscaffold when irradiated with LED light on an area of 6 mm diameter was 0.028 mm 3 . In other words, it is possible to fill the space between the cells and the scaffold with gas in 0.3 s, so that cells can be sufficiently detached by the gas generated from this nanoscaffold.…”

“…Tissue engineering has been widely explored within the field of biomedicine since the first groundbreaking study by Langer and Vacanti during the 1980s. (1) Tissue engineering has been applied to many different types of tissues, including cardiac, (2) cartilaginous, (3) corneal, (4) bladder, (5) and liver (6) tissues. More recently, stem-cell-like embryonic stem (ES) cells (7) and induced pluripotent stem (iPS) cells (8) have been discovered and incorporated into engineered tissues.…”

Current perspectives on biological approaches for osteoarthritis

“…These monolayers can be manipulated by wrapping or draping them over structures. This technique has been successfully reported with chondrocytes in the repair of microtia, osteochondral defects, and even cardiac defects …”