Tissue engineered cartilage substitutes, which induce the process of endochondral ossification, represent a regenerative strategy for bone defect healing. Such constructs typically consist of multipotent mesenchymal stromal cells (MSCs) forming a cartilage template in vitro, which can be implanted to stimulate bone formation in vivo. The use of MSCs of allogeneic origin could potentially improve the clinical utility of the tissue engineered cartilage constructs in three ways. First, ready-to-use construct availability can speed up the treatment process. Second, MSCs derived and expanded from a single donor could be applied to treat several patients and thus the costs of the medical interventions would decrease. Finally, it would allow more control over the quality of the MSC chondrogenic differentiation. However, even though the envisaged clinical use of allogeneic cell sources for bone regeneration is advantageous, their immunogenicity poses a significant obstacle to their clinical application. The aim of this review is to increase the awareness of the role played by immune cells during endochondral ossification, and in particular during regenerative strategies when the immune response is altered by the presence of implanted biomaterials and/or cells. More specifically, we focus on how this balance between immune response and bone regeneration is affected by the implantation of a cartilaginous tissue engineered construct of allogeneic origin.

诱导软骨内骨化过程的组织工程软骨替代物代表了骨缺损愈合的再生策略。此类构建体通常由在体外形成软骨模板的多能间充质基质细胞（MSC）组成，可以将其植入体内以刺激骨骼形成。同种异体来源的MSC的使用可以通过三种方式潜在地改善组织工程软骨构建体的临床实用性。首先，随时可用的构建体可用性可以加快处理过程。第二，从单个供体衍生和扩增的MSC可用于治疗多名患者，因此医疗干预措施的成本将降低。最后，它可以更好地控制MSC软骨分化的质量。然而，尽管设想将异体细胞来源用于骨再生的临床应用是有利的，但是它们的免疫原性对其临床应用构成了重大障碍。这篇综述的目的是提高人们对免疫细胞在软骨内骨化过程中，尤其是在再生策略中因植入的生物材料和/或细胞的存在而改变免疫反应的作用的认识。更具体地说，我们关注同种异体起源的软骨组织工程构建体的植入如何影响免疫反应和骨骼再生之间的这种平衡。这篇综述的目的是提高人们对免疫细胞在软骨内骨化过程中，尤其是在再生策略中因植入的生物材料和/或细胞的存在而改变免疫反应的作用的认识。更具体地说，我们关注同种异体起源的软骨组织工程构建体的植入如何影响免疫反应和骨骼再生之间的这种平衡。这篇综述的目的是提高人们对免疫细胞在软骨内骨化过程中，尤其是在再生策略中因植入的生物材料和/或细胞的存在而改变免疫反应的作用的认识。更具体地说，我们关注同种异体起源的软骨组织工程构建体的植入如何影响免疫反应和骨骼再生之间的这种平衡。