Katzenback Barbara A, Belosevic Miodrag
Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
Dev Comp Immunol. 2009 Nov;33(11):1165-75. doi: 10.1016/j.dci.2009.06.005. Epub 2009 Jun 25.
Kit ligand and its type III tyrosine kinase receptor Kit promotes the survival, proliferation and differentiation of progenitor cells involved in mammalian myelopoiesis. In this study we report on the molecular and functional characterization of kit receptor A (kita) and kit ligand A (kitla) from the goldfish. Both kita and kitla were ubiquitously expressed in goldfish tissues, with higher mRNA levels observed in the kidney and spleen, the major hematopoietic organs of fish. Furthermore, both kita and kitla expressions decreased in a time-dependent manner in goldfish primary kidney macrophage (PKM) cultures, as progenitor to macrophage development progressed, and the highest expressions of both the receptor and ligand were observed in sorted progenitor cell populations. Activation of mature macrophage cultures increased both kita and kitla expressions. Kit ligand A induced chemotactic response, proliferation and survival of PKM cells in a dose-dependent manner, but did not induce differentiation of early PKM cells. These results are consistent with the role of kita and kitla during myelopoiesis of higher vertebrates and suggest a conserved mechanism of macrophage development throughout vertebrates.
干细胞因子及其Ⅲ型酪氨酸激酶受体c-Kit可促进参与哺乳动物骨髓生成的祖细胞的存活、增殖和分化。在本研究中，我们报道了金鱼c-Kit受体A（kita）和干细胞因子配体A（kitla）的分子及功能特性。kita和kitla在金鱼组织中均广泛表达，在鱼类主要造血器官肾脏和脾脏中观察到较高的mRNA水平。此外，在金鱼原代肾巨噬细胞（PKM）培养物中，随着祖细胞向巨噬细胞发育的进行，kita和kitla的表达均呈时间依赖性下降，并且在分选的祖细胞群体中观察到受体和配体的最高表达。成熟巨噬细胞培养物的激活增加了kita和kitla的表达。干细胞因子配体A以剂量依赖性方式诱导PKM细胞的趋化反应、增殖和存活，但不诱导早期PKM细胞的分化。这些结果与kita和kitla在高等脊椎动物骨髓生成过程中的作用一致，并提示整个脊椎动物巨噬细胞发育存在保守机制。
