Division of Pediatric Oncology, Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Cytometry A. 2013 Jan;83(1):134-40. doi: 10.1002/cyto.a.22227. Epub 2012 Nov 26.
The stromal-vascular fraction (SVF) of adipose tissue is a rich source of multipotent stem cells. We and others have described three major populations of stem/progenitor cells in this fraction, all closely associated with small blood vessels: endothelial progenitor cells (EPC, CD45-/CD31+/CD34+), pericytes (CD45-/CD31-/CD146+), and supra-adventitial adipose stromal cells (SA-ASC, CD45-/CD31-/CD146-/CD34+). EPC are luminal, pericytes are adventitial, and SA-ASC surround the vessel like a sheath. The multipotency of the pericytes and SA-ASC compartments is strikingly similar to that of CD45-/CD34-/CD73+/CD105+/CD90+ bone marrow-derived mesenchymal stem cells (BM-MSC). Here, we determine the extent to which this mesenchymal pattern is expressed on the three adipose stem/progenitor populations. Eight independent adipose tissue samples were analyzed in a single tube (CD105-FITC/CD73-PE/CD146-PETXR/CD14-PECY5/CD33-PECY5/CD235A-PECY5/CD31-PECY7/CD90-APC/CD34-A700/CD45-APCCY7/DAPI). Adipose EPC were highly proliferative with (14.3 ± 2.8)% (mean ± SEM) having >2N DNA. About half (53.1 ± 7.6)% coexpressed CD73 and CD105, and (71.9 ± 7.4)% expressed CD90. Pericytes were less proliferative [(8.2 ± 3.4)% >2N DNA)] with a smaller proportion [(29.6 ± 6.9)% CD73+/CD105+, (60.5 ± 10.2)% CD90+] expressing mesenchymal associated markers. However, the CD34+ subset of CD146+ pericytes were both highly proliferative [(15.1 ± 3.6)% with >2N DNA] and of uniform mesenchymal phenotype [(93.3 ± 3.7)% CD73+/CD105+, (97.8 ± 0.7)% CD90+], suggesting transit amplifying progenitor cells. SA-ASC were the least proliferative [(3.7 ± 0.8)%>2N DNA] but were also highly mesenchymal in phenotype [(94.4 ± 3.2)% CD73+/CD105+, (95.5 ± 1.2)% CD90+]. These data imply a progenitor/progeny relationship between pericytes and SA-ASC, the most mesenchymal of SVF cells. Despite phenotypic and functional similarities to BM-MSC, SA-ASC are distinguished by CD34 expression.
脂肪组织的基质血管部分（SVF）是多能干细胞的丰富来源。我们和其他人已经在这个部分描述了三种主要的干细胞/祖细胞群体，它们都与小血管密切相关：内皮祖细胞（EPC，CD45-/CD31+/CD34+）、周细胞（CD45-/CD31-/CD146+）和超囊脂肪基质细胞（SA-ASC，CD45-/CD31-/CD146-/CD34+）。EPC 是管腔的，周细胞是 Adventitial 的，SA-ASC 像鞘一样围绕着血管。周细胞和 SA-ASC 区室的多能性与 CD45-/CD34-/CD73+/CD105+/CD90+骨髓来源的间充质干细胞（BM-MSC）非常相似。在这里，我们确定了这种间充质模式在三种脂肪干细胞/祖细胞群体上表达的程度。对 8 个独立的脂肪组织样本在一个管中进行了分析（CD105-FITC/CD73-PE/CD146-PETXR/CD14-PECY5/CD33-PECY5/CD235A-PECY5/CD31-PECY7/CD90-APC/CD34-A700/CD45-APCCY7/DAPI）。脂肪 EPC 具有高度的增殖性，（14.3±2.8）%（平均值±SEM）具有>2N DNA。大约一半（53.1±7.6）%同时表达 CD73 和 CD105，（71.9±7.4）%表达 CD90。周细胞增殖性较低[（8.2±3.4）%>2N DNA）]，表达间充质相关标志物的比例较小[（29.6±6.9）% CD73+/CD105+，（60.5±10.2）% CD90+]。然而，CD146+周细胞的 CD34+亚群均具有高度的增殖性[（15.1±3.6）%具有>2N DNA]，并且具有均匀的间充质表型[（93.3±3.7）% CD73+/CD105+，（97.8±0.7）% CD90+]，提示过渡扩增祖细胞。SA-ASC 是增殖性最低的[（3.7±0.8）%>2N DNA]，但表型也高度间充质化[（94.4±3.2）% CD73+/CD105+，（95.5±1.2）% CD90+]。这些数据表明周细胞和 SA-ASC 之间存在祖细胞/祖细胞关系，它们是 SVF 细胞中最间充质化的。尽管与 BM-MSC 具有表型和功能上的相似性，但 SA-ASC 因其 CD34 表达而不同。
