Chondrocyte apoptosis in the regenerated articular cartilage after allogenic chondrocyte transplantation in the rabbit knee

Abstract

We attempted to repair full-thickness defects in the articular cartilage of the trochlear groove of the femur in 30 rabbit knee joints using allogenic cultured chondrocytes embedded in a collagen gel. The repaired tissues were examined at 2, 4, 8, 12 and 24 weeks after operation using histological and histochemical methods. The articular defect filling index measurement was derived from safranin-O stained sections. Apoptotic cellular fractions were derived from analysis of apoptosis in situ using TUNEL staining, and was confirmed using caspase-3 staining along with quantification of the total cellularity. The mean articular defect filling index decreased with time. After 24 weeks it was 0.7 (SD 0.10), which was significantly lower than the measurements obtained earlier (p < 0.01). The highest mean percentage of apoptotic cells were observed at 12 weeks, although the total cellularity decreased with time. Because apoptotic cell death may play a role in delamination after chondrocyte transplantation, anti-apoptotic gene therapy may protect transplanted chondrocytes from apoptosis.

Increased Chondrocyte Death after Steroid and Local Anesthetic Combination

“…This method allowed us to examine cartilage specimens histologically for identification and quantification of TUNEL-positive cells in situ, which represent apoptotic cell death in the tissue [10,30]. After a 24-hour treatment with various solutions (Table 1), sections were stained following the manufacturer's instructions.…”

Allogeneic chondrocyte implantation: What is stopping it from being a standard of care?

“…[6,7] Despite the huge potential, limitations exist with respect to culture and clinical domains, and we attempt to provide an account of the same [Table 1], with potential solutions to tackle them. Various important studies [5][6][7][8][9][10][11][12][13][14][15][16][17][18] conducted to highlight the…”

Cartilage repair: past and future – lessons for regenerative medicine

“…Pro‐inflammatory cytokines and pro‐apoptotic factors may be induced by local inflammation and also by the processing and storage of the cells and tissues prior to implantation [146]. It has been demonstrated that some chondrocytes used in chondrocyte transplantation undergo apoptosis [147], which may be due to a unique process known as chondroptosis. Therefore, the modulation of factors that interfere with this process may be of relevance to cartilage repair.…”