在哺乳動(dòng)物器官中，肝臟是獨(dú)特的,，因?yàn)樵谠獾絿?yán)重性組織損傷或者甚至是手術(shù)部分摘取后，它能夠再生,。

來自美國(guó)南加州大學(xué)洛杉磯分校的Laurie DeLeve和她的同事們想要更好地理解哪些細(xì)胞特異性地促進(jìn)肝臟再生,。

人們通常認(rèn)為一類特殊的細(xì)胞，即肝竇內(nèi)皮細(xì)胞(liver sinusoidal endothelial cell),，促進(jìn)肝組織再生,。然而，DeLeve領(lǐng)導(dǎo)的研究小組猜測(cè)能夠分化為成熟細(xì)胞類型的干細(xì)胞和祖細(xì)胞可能通過產(chǎn)生肝細(xì)胞生長(zhǎng)因子來負(fù)責(zé)促進(jìn)肝臟再生,。

利用大鼠模式系統(tǒng),，他們首先確定在肝臟和骨髓中存在產(chǎn)生肝竇內(nèi)皮細(xì)胞的干細(xì)胞和祖細(xì)胞。他們接著研究它們當(dāng)中哪些細(xì)胞群體是肝臟再生所必需的,。DeLeve和同事們發(fā)現(xiàn)在沒有損傷時(shí),，骨髓來源的干細(xì)胞和祖細(xì)胞不是肝細(xì)胞增殖所必需的。

然而,，在手術(shù)摘除大鼠部分肝臟之后,，灌注骨髓來源的祖細(xì)胞是肝臟再生所必需的。這些結(jié)果有望加強(qiáng)人們對(duì)肝組織遭受損傷后如何再生的理解,，而且也可能有助于理解骨髓組織受到抑制的病人產(chǎn)生的肝臟并發(fā)癥,。(生物谷：towersimper編譯)

doi:10.1172/JCI58789
PMC:
PMID:
Liver sinusoidal endothelial cell progenitor cells promote liver regeneration in rats

Lin Wang, Xiangdong Wang, Guanhua Xie, Lei Wang, Colin K. Hill and Laurie D. DeLeve

The ability of the liver to regenerate is crucial to protect liver function after injury and during chronic disease. Increases in hepatocyte growth factor (HGF) in liver sinusoidal endothelial cells (LSECs) are thought to drive liver regeneration. However, in contrast to endothelial progenitor cells, mature LSECs express little HGF. Therefore, we sought to establish in rats whether liver injury causes BM LSEC progenitor cells to engraft in the liver and provide increased levels of HGF and to examine the relative contribution of resident and BM LSEC progenitors. LSEC label-retaining cells and progenitors were identified in liver and LSEC progenitors in BM. BM LSEC progenitors did not contribute to normal LSEC turnover in the liver. However, after partial hepatectomy, BM LSEC progenitor proliferation and mobilization to the circulation doubled. In the liver, one-quarter of the LSECs were BM derived, and BM LSEC progenitors differentiated into fenestrated LSECs. When irradiated rats underwent partial hepatectomy, liver regeneration was compromised, but infusion of LSEC progenitors rescued the defect. Further analysis revealed that BM LSEC progenitors expressed substantially more HGF and were more proliferative than resident LSEC progenitors after partial hepatectomy. Resident LSEC progenitors within their niche may play a smaller role in recovery from partial hepatectomy than BM LSEC progenitors, but, when infused after injury, these progenitors engrafted and expanded markedly over a 2-month period. In conclusion, LSEC progenitor cells are present in liver and BM, and recruitment of BM LSEC progenitors is necessary for normal liver regeneration.