Animal Models for Cartilage Regeneration and Repair

Abstract

cartilage injury and degeneration are leading causes of disability. Animal studies are critically important to developing effective treatments for cartilage injuries. This review focuses on the use of animal models for the study of the repair and regeneration of focal cartilage defects. Animals commonly used in cartilage repair studies include murine, lapine, canine, caprine, porcine, and equine models. There are advantages and disadvantages to each model. Small animal rodent and lapine models are cost effective, easy to house, and useful for pilot and proof-of-concept studies. The availability of transgenic and knockout mice provide opportunities for mechanistic in vivo study. Athymic mice and rats are additionally useful for evaluating the cartilage repair potential of human cells and tissues. Their small joint size, thin cartilage, and greater potential for intrinsic healing than humans, however, limit the translational value of small animal models. Large animal models with thicker articular cartilage permit study of both partial thickness and full thickness chondral repair, as well as osteochondral repair. Joint size and cartilage thickness for canine, caprine, and mini-pig models remain significantly smaller than that of humans. The repair and regeneration of chondral and osteochondral defects of size and volume comparable to that of clinically significant human lesions can be reliably studied primarily in equine models. While larger animals may more closely approximate the human clinical situation, they carry greater logistical, financial, and ethical considerations. A multifactorial analysis of each animal model should be carried out when planning in vivo studies. Ultimately, the scientific goals of the study will be critical in determining the appropriate animal model.

Tissue engineering‐based cartilage repair with mesenchymal stem cells in a porcine model

“…14,15 Although various smaller animal species have been used in articular cartilage defect studies, the use of pigs, which are large animals with a body weight similar to humans, enabled us to develop a large animal defect model that is better able to mimic the human condition than is possible with smaller animal models. 16,17 In our previous in vivo study, we compared the ability of spontaneous healing, scaffold alone, autogenous osteochondral transfer, and the chondrocyte-scaffold tissue constructs to repair full thickness and osteochondral cartilage defects. 13 The two cell containing implants performed better than spontaneous healing or scaffold alone.…”

The effects of hypothyroidism on the proximal femoral physis in miniature swine

“…Utilization of miniature swine facilitated this particular study, and this animal model has become popular in other areas of research. [33][34][35] The present work demonstrates success with these animals in producing a biochemically mediated state of hypothyroidism and obviated the need for surgically induced hypothyroidism. In addition, the size of miniature swine proximal femurs provides suitable specimen mass and numbers for evaluating physes by histological, histomorphometric and gene expression analyses.…”

Comparison between two different experimental models of osteoarthritis in rabbits. Intra-articular collagenase injection and anterior cruciate ligament transection

“…The rabbit model appeared to be practical for early therapy evaluation stages due to its relative cost effectiveness, easy handling and to the animal's joint size, which is suitable for surgical procedures 14 , as shown in the present study. Nonetheless, the welfare during experimental procedures is of concern in most research centers worldwide.…”