Rezzadeh Kameron S, Hokugo Akishige, Jewett Anahid, Kozlowska Anna, Segovia Luis Andres, Zuk Patricia, Jarrahy Reza
Los Angeles, Calif. From the Regenerative Bioengineering and Repair Laboratory, Division of Plastic and Reconstructive Surgery, Department of Surgery, David Geffen School of Medicine at the University of California, Los Angeles; and the Division of Oral Biology and Oral Medicine, The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, University of California, Los Angeles, School of Dentistry.
Plast Reconstr Surg. 2015 Sep;136(3):503-510. doi: 10.1097/PRS.0000000000001536.
Natural killer cells are thought to represent more than 30 percent of all lymphocytes within the stromal vascular fraction of lipoaspirates. However, their physiologic interaction with adipocytes and their precursors has never been specifically examined. The authors hypothesized that natural killer cells, by means of cytokine secretion, are capable of promoting the differentiation of adipose-derived stem cells.
Human natural killer cells purified from healthy donors' peripheral blood mononuclear cells were activated with a combination of interleukin-2 and anti-CD16 monoclonal antibody; natural killer cell supernatant was collected. Adipose-derived stem cells isolated from raw human lipoaspirates from healthy patients were treated with growth media, growth media with natural killer cell supernatant, adipogenic media, and adipogenic media with natural killer cells supernatant. Flow cytometric analysis was performed on cells using antibodies against B7H1, CD36, CD44, CD34, CD29, and MHC-1. Adipogenic-related gene expression (PPAR-γ, LPL, GPD-1, and aP2) was assessed. Oil Red O staining was performed as a functional assay of adipocyte differentiation and adipogenesis.
Adipose-derived stem cells maintained in growth media with natural killer cell supernatant lost markers of "stemness," including CD44, CD34, and CD29; and expressed markers of differentiation, including B7H1 and MHC-1. Adipose-derived stem cells treated with natural killer cell supernatant accumulated small amounts of lipid after 10 days of natural killer cell supernatant treatment. Adipose-derived stem cells treated with natural killer cell supernatant showed altered expression of adipogenesis-associated genes compared with cells maintained in growth media. Adipose-derived stem cells maintained in adipogenic media with natural killer cell supernatant accumulated less lipid than those cells in adipogenic media alone.
The authors demonstrate that, through secreted factors, natural killer cells are capable of differentiating adipose-derived stem cells. In cells maintained in adipogenic media, treatment with natural killer cell supernatant modulated adipogenic potential.
自然杀伤细胞被认为占脂肪抽吸物基质血管成分中所有淋巴细胞的30%以上。然而，它们与脂肪细胞及其前体的生理相互作用从未得到过专门研究。作者推测自然杀伤细胞通过分泌细胞因子能够促进脂肪来源干细胞的分化。
从健康供体的外周血单个核细胞中纯化得到的人自然杀伤细胞用白细胞介素-2和抗CD16单克隆抗体联合激活；收集自然杀伤细胞上清液。从健康患者的原始脂肪抽吸物中分离出的脂肪来源干细胞分别用生长培养基、添加自然杀伤细胞上清液的生长培养基、成脂培养基以及添加自然杀伤细胞上清液的成脂培养基处理。使用抗B7H1、CD36、CD44、CD34、CD29和MHC-1的抗体对细胞进行流式细胞术分析。评估与成脂相关的基因表达（PPAR-γ、LPL、GPD-1和aP2）。进行油红O染色作为脂肪细胞分化和成脂的功能检测。
在添加自然杀伤细胞上清液的生长培养基中培养的脂肪来源干细胞失去了“干性”标志物，包括CD44、CD34和CD29；并表达了分化标志物，包括B7H1和MHC-1。用自然杀伤细胞上清液处理10天后，脂肪来源干细胞积累了少量脂质。与在生长培养基中培养的细胞相比，用自然杀伤细胞上清液处理的脂肪来源干细胞显示出成脂相关基因表达的改变。在添加自然杀伤细胞上清液的成脂培养基中培养的脂肪来源干细胞比单独在成脂培养基中培养的细胞积累的脂质更少。
作者证明，自然杀伤细胞通过分泌因子能够使脂肪来源干细胞分化。在成脂培养基中培养的细胞中，用自然杀伤细胞上清液处理可调节成脂潜能。
