Thorgeirsson Snorri S, Grisham Joe W
Laboratory of Experimental Carcinogenesis, Center for Cancer Research, National Cancer Institute/NIH, Bethesda, MD 20892-4262, USA.
Hepatology. 2006 Jan;43(1):2-8. doi: 10.1002/hep.21015.
The authors reviewed 77 published reports available before August 1, 2005 that examined the ability of hematopoietic cells to generate hepatocytes in the liver. A list of these publications and a synopsis of each are available on-line. We interpret the evidence provided by this data set to suggest that one or more types of hematopoietic cells may rarely acquire the hepatocyte phenotype in the liver (frequency < or =10(-4)), although the nature of the hematopoietic cells involved and the mechanisms responsible for acquisition of a hepatocyte phenotype are still controversial. Hematopoietic stem cells do not appear to be direct precursors of hepatocytes, which, instead, can be generated from cells of the macrophage-monocyte lineage. Fusion between hepatocytes and transplanted hematopoietic cells has been substantiated as a mechanism by which hepatocytes that carry a bone marrow tag are generated, but direct transdifferentiation of hematopoietic cells has not been demonstrated. In conclusion, hematopoietic cells contribute little to hepatocyte formation under either physiological or pathological conditions, although they may provide cytokines and growth factors that promote hepatocyte functions by paracrine mechanisms. Cells of the endodermal hepatocyte lineage are far more potent generators of hepatocytes than are hematopoietic cells.
作者回顾了2005年8月1日前发表的77份报告，这些报告研究了造血细胞在肝脏中生成肝细胞的能力。这些出版物的列表及其每份报告的摘要可在线获取。我们对该数据集提供的证据进行解读，认为一种或多种造血细胞可能在肝脏中极少获得肝细胞表型（频率≤10⁻⁴），尽管所涉及的造血细胞的性质以及获得肝细胞表型的机制仍存在争议。造血干细胞似乎不是肝细胞的直接前体，相反，肝细胞可由巨噬细胞 - 单核细胞谱系的细胞产生。肝细胞与移植的造血细胞之间的融合已被证实是产生携带骨髓标记的肝细胞的一种机制，但造血细胞的直接转分化尚未得到证实。总之，在生理或病理条件下，造血细胞对肝细胞形成的贡献很小，尽管它们可能通过旁分泌机制提供促进肝细胞功能的细胞因子和生长因子。内胚层肝细胞谱系的细胞比造血细胞更能有效地生成肝细胞。
