Inamdar M, Koch T, Rapoport R, Dixon J T, Probolus J A, Cram E, Bautch V L
Department of Biology, University of North Carolina at Chapel Hill, 27599, USA.
Dev Dyn. 1997 Dec;210(4):487-97. doi: 10.1002/(SICI)1097-0177(199712)210:4<487::AID-AJA11>3.0.CO;2-4.
Macrophages are phagocytic hematopoietic cells involved in several immune processes, but they are also present early in mammalian development and may participate in embryonic tissue remodeling. We have isolated and characterized a cell line, Py-YSA, from the mouse yolk sac. Py-YSA cells have several functional properties of macrophages, including uptake of acetylated low density lipoprotein and phagocytic capability. They express the murine macrophage markers F4/80 and Mac-1, and they express RNA for the c-fms receptor. Their expansion in culture requires fibroblast conditioned medium or exogenous monocyte-colony stimulating factor. Murine ES (embryonic stem) cell cultures that undergo in vitro differentiation recapitulate yolk sac development, and during this process cells arise that express both Mac-1 and F4/80 and morphologically resemble the Py-YSA cells. The kinetics and distribution pattern of the Mac-1+ cells during a time course of ES cell differentiation suggest that they originate in the blood islands, and that they subsequently leave the blood islands and disperse to tissue sites. Both F4/80 and Mac-1 are first expressed in primary cultures from day 9.5 yolk sacs. The Py-YSA cultured cells thus resemble embryonic tissue macrophages by several criteria, and they share a marker profile with a cell type found in yolk sacs and differentiating ES cells. Py-YSA cells will be a useful reagent for further understanding the role of embryonic tissue macrophages in development.
巨噬细胞是参与多种免疫过程的吞噬性造血细胞，但它们在哺乳动物发育早期也存在，并且可能参与胚胎组织重塑。我们从小鼠卵黄囊中分离并鉴定了一种细胞系Py - YSA。Py - YSA细胞具有巨噬细胞的多种功能特性，包括摄取乙酰化低密度脂蛋白和吞噬能力。它们表达小鼠巨噬细胞标志物F4/80和Mac - 1，并且表达c - fms受体的RNA。它们在培养中的扩增需要成纤维细胞条件培养基或外源性单核细胞集落刺激因子。经历体外分化的小鼠胚胎干细胞（ES）培养物重现了卵黄囊发育过程，在此过程中出现了表达Mac - 1和F4/80且形态上类似于Py - YSA细胞的细胞。ES细胞分化过程中Mac - 1 +细胞的动力学和分布模式表明它们起源于血岛，随后离开血岛并分散到组织部位。F4/80和Mac - 1均首先在9.5天龄卵黄囊的原代培养物中表达。因此，Py - YSA培养细胞在几个标准上类似于胚胎组织巨噬细胞，并且它们与在卵黄囊和分化的ES细胞中发现的一种细胞类型具有相同的标志物谱。Py - YSA细胞将成为进一步了解胚胎组织巨噬细胞在发育中作用的有用试剂。
