Abstract
Background
Aseptic loosening of prostheses is the most common cause for failure in total joint arthroplasty. Particulate wear debris induces a non-stop inflammatory-like response resulting in the formation of a layer of fibrous periprosthetic tissue at the bone/implant interface. The current treatment is an invasive revision joint replacement surgery. However, this procedure has a high morbidity rate, therefore, a less invasive alternative is necessary. One approach could be to re-establish osseointegration of the joint prosthesis by inducing osteoblast differentiation in the periprosthetic tissue. Therefore, the aim of this study was to investigate the capacity of periprosthetic tissue cells to differentiate into the osteoblast lineage.
Methods
Periprosthetic tissue samples were collected during revision surgery of aseptic loosened hip prostheses, after which cells were isolated by collagenase digestion. Of 14 different donors, cells from passage 1 till 3 were used for differentiation experiments. During 21 days, cells were cultured under normal and several osteogenic culture conditions. Cultures were stained for alkaline phosphatase (ALP) activity and mineral deposits in the extracellular matrix.
Results
When cells were cultured in osteogenic medium, ALP staining was increased compared to normal culture medium in 12 donors. Mineralisation of the matrix was observed in 13 donors. Addition of bone morphogenetic protein 2 or 6 (BMP) increased the ALP staining even further in 4 donors, whereas the mineralisation increased by 2–3 fold in 2 different donors. Nevertheless, in 1 donor, addition of a specific GSK3β inhibitor (GIN) to the osteogenic medium or a combination of both GIN and BMP2 was required to induce mineralisation of the matrix.
Conclusions
Periprosthetic tissue cells show characteristics of differentiation into the osteoblast lineage when cultured under osteogenic conditions. However, the responses to different osteogenic stimuli were donor specific.
Level of Evidence
Level IV. Experimental research study.
