THE MANIPULATED MESENCHYMAL STEM-CELLS IN REGENERATED SKELETAL TISSUES

Ample experimental examples have been accumulated during the last 3 de cades indicating the ability of exogenous sources of cultured cells to serve as implants accelerating cartilage regeneration in defects of a rticular surfaces, In some cases, the repair tissues form complete spa tial reconstruction of the defect, In other cases, either the spatial reconstruction is incomplete or the quality of the reparative tissue i s inadequate. A delayed pace of endochondral ossification in the deep zones of the subchondral region of the defects, or ossification above the tide mark, within the superficial cartilaginous articular regions have been noted, Therefore, even in this promising approach of biologi cal resurfacing procedure results are not certain, and further investi gative research efforts are required, In the current study, a comparis on of implantations of various cultured cells of four different source s were tested in an avian system, The reparative tissue outcomes are d ivided into three grades: full regeneration success, partial success, and failure of regeneration according to qualitative histological para meters and quantitative observation of the gross specimen, Defects tha t failed to regenerate a completely filled lesion were found to contai n cells carrying the preskeletal-precartilaginous characteristic marke r of FGFR3., The findings based on the above parameters suggest that a utogeneic, chondrocytic-enriched bone marrow derived mesenchymal cells are superior to other cell sources for articular cartilage regenerati on, Grafting of defects with these cells results in a 100% success rat e, Allogeneic limb bud-derived mesenchymal cells and allogeneic embryo nal chondrocytes have both reached a success of 75% of completely fill ed defects, Allogeneic chondrocytic-enriched bone marrow-derived mesen chymal cells yielded a 31% success rate, Untreated defects completely failed to heal, In successfully healed defects no cells of the reparat ive tissue carry the FGFR3 marker 3 months postimplantation, In partia lly healed defects, FGFR3 positive staining is present in fibrous cell s at the invaginated surface, These latest findings may suggest some k ind of proliferation failure in such cases, (C) 1998 Elsevier Science Inc.