# b& g! k4 V! h* ]. g% H4 C3 ?3 L我们一直在MCSs临床关注的越来越多,但进展一直缓慢,因为研究人员迄今已无法辨认MSCs,研究其在身体内的正常生理功能。我们发现,被称为瘦蛋白受体的蛋白可以作为一种生物标记,准确地识别成人骨髓内MSCs,而且这些MSCs是新骨形成和骨修复损伤后的主要来源。0 M7 _! S- i5 }8 @8 A
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在他们的研究过程中,研究人员发现瘦素受体阳性细胞也是促进骨髓中造血干细胞维持的因素的主要来源。不幸的是,许多临床试验正在测试使用MSCs疗法的潜力,已经被阻碍,利用的培养细胞缺乏特征和不纯。如果这一发现被复制在人类MSCs,可以增加利用MSCs精心设计临床试验的成功概率。 & N( V* N2 C# w $ F9 K7 T/ ^+ ~0 e# B
doi:10.1016/j.stem.2014.06.008+ h% C/ m( R( x/ S, F$ Z
PMC: 5 B" @- _/ h2 U+ J& nPMID:8 V3 I; ]/ ?9 L; m1 b% Y, r
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Leptin-Receptor-Expressing Mesenchymal Stromal Cells Represent the Main Source of Bone Formed by Adult Bone Marrow 4 e# o1 x% D7 k) V( z" }1 u: K9 [ k; H7 [" d4 E: s$ G' w& X5 {7 n" a
Bo O. Zhou, Rui Yue, Malea M. Murphy, James G. Peyer, Sean J. Morrison ?2 `4 [5 a+ g0 i0 Q9 j6 N2 O$ x$ \: _' a1 d' J/ R
Summary: Studies of the identity and physiological function of mesenchymal stromal cells (MSCs) have been hampered by a lack of markers that permit both prospective identification and fate mapping in vivo. We found that Leptin Receptor (LepR) is a marker that highly enriches bone marrow MSCs. Approximately 0.3% of bone marrow cells were LepR+, 10% of which were CFU-Fs, accounting for 94% of bone marrow CFU-Fs. LepR+ cells formed bone, cartilage, and adipocytes in culture and upon transplantation in vivo. LepR+ cells were Scf-GFP+, Cxcl12-DsRedhigh, and Nestin-GFPlow, markers which also highly enriched CFU-Fs, but negative for Nestin-CreER and NG2-CreER, markers which were unlikely to be found in CFU-Fs. Fate-mapping showed that LepR+ cells arose postnatally and gave rise to most bone and adipocytes formed in adult bone marrow, including bone regenerated after irradiation or fracture. LepR+ cells were quiescent, but they proliferated after injury. Therefore, LepR+ cells are the major source of bone and adipocytes in adult bone marrow. % d" y% }7 X. R7 q ' ?. a8 e7 o/ @' ~! s; c _