Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA, USA; 3Bs Research Group, Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Avepark, Guimarães, Portugal; ICVS/3Bs PT Government Associated Laboratory, Braga/Guimarães, Portugal.
J Tissue Eng Regen Med. 2014 Oct;8(10):757-62. doi: 10.1002/term.1565. Epub 2012 Jul 16.
Since inflammatory mechanisms have been postulated to link obesity to osteoarthritis, the current study evaluated the ratio of immune cells to multipotent stromal cells within the infrapatellar fat pad (IPFP) and subcutaneous adipose tissue (SQ) of the knee; each depot has potential as a source of regenerative cells. The immunophenotypes of stromal vascular fraction (SVF) and adipose-derived stem cells (ASCs) of the IPFP and SQ were determined in tissues from osteoarthritic subjects (n = 7) undergoing total knee replacement. Based on a subset of surface antigens, the immunophenotype of ASCs from SQ of OA subjects was not significantly different from that of relatively healthy and leaner subjects undergoing elective liposuction surgery. Flow-cytometry comparison of SVF cell populations in the IPFP of OA subjects resembled those within the subject's own matched SQ, with the exception of the endothelial marker CD31(+) , which was significantly greater in cells from SQ. In the OA subjects, lower numbers of capillary-like structures and higher numbers of stromal and alkaline phosphatase colony-forming units in the IPFP vs SQ were consistent with this finding; however, ASCs from both depots in OA subjects exhibited comparable adipogenic and osteogenic differentiation potential. Thus, the IPFP contains an ASC and immune cell population similar to that of donor-matched SQ, making it an alternative ASC source for tissue regeneration. Further studies will be needed to determine whether IPFP immune cell infiltrates play an aetiological role in osteoarthritis equivalent to that shown in diabetes associated with obesity.
由于炎症机制被认为将肥胖与骨关节炎联系起来，因此目前的研究评估了膝关节下髌旁脂肪垫（IPFP）和皮下脂肪组织（SQ）中免疫细胞与多能基质细胞的比例；每个脂肪垫都有可能成为再生细胞的来源。对接受全膝关节置换术的骨关节炎患者（n=7）的 IPFP 和 SQ 组织中的基质血管部分（SVF）和脂肪来源干细胞（ASC）的免疫表型进行了确定。基于一组表面抗原，OA 患者 SQ 的 ASC 免疫表型与接受选择性吸脂手术的相对健康和较瘦的患者没有显着差异。OA 患者 IPFP 中 SVF 细胞群的流式细胞术比较与患者自身匹配的 SQ 中的细胞群相似，除了内皮标记物 CD31（+），该标志物在 SQ 中的细胞中显着更高。在 OA 患者中，IPFP 中的毛细血管样结构数量较少，基质和碱性磷酸酶集落形成单位数量较多，与这一发现一致；然而，OA 患者两个部位的 ASC 均表现出类似的成脂和成骨分化潜力。因此，IPFP 包含与供体匹配的 SQ 相似的 ASC 和免疫细胞群体，使其成为组织再生的替代 ASC 来源。需要进一步研究以确定 IPFP 免疫细胞浸润是否在骨关节炎的发病机制中发挥与肥胖相关的糖尿病中所示的相同作用。
