Lampisuo M, Karvinen J, Petteri Arstila T, Lassila O
Department of Medical Microbiology, Turku University, Finland.
Scand J Immunol. 1995 Jan;41(1):65-9. doi: 10.1111/j.1365-3083.1995.tb03534.x.
T cell precursors in the chick embryo have been localized into the intraembryonic mesenchyme (IEM) and into the para-aortic region before the first wave of the thymic colonization on embryonic day (ED) 6,5-8. The cell surface markers of avian prethymic stem cells are not known. It is also not known whether these precursor cells are already committed to the T cell lineage before their thymic colonization. In 7-day-old chick embryos Ov+ cells were found in the para-aortic region. Also the endothelial cells of the embryonic dorsal aorta were positively stained. Ov antigen might represent a very primitive marker for precursor cells having the potentiality to differentiate both to haemopoietic and endothelial cells. Scattered CD45+ cells were observed in the same para-aortic area as in many haemopoietic areas in the loose embryonic mesenchymal tissues. CD8 alpha (MoAb 3-298) expressing haemopoietic cells were detected before thymic colonization on ED6. In flow cytometric analysis of IEM precursors Ov, CD45 and CD8 alpha expressing cells seemed to form distinct subsets suggesting heterogeneity of these haemopoietic cells.
鸡胚中的T细胞前体在胚胎第6.5 - 8天胸腺首次定植之前，已定位到胚胎内间充质（IEM）和主动脉旁区域。禽类胸腺前体细胞的细胞表面标志物尚不清楚。这些前体细胞在胸腺定植之前是否已确定为T细胞谱系也不清楚。在7日龄鸡胚中，在主动脉旁区域发现了Ov +细胞。胚胎背主动脉的内皮细胞也呈阳性染色。Ov抗原可能是前体细胞的一个非常原始的标志物，这些前体细胞具有分化为造血细胞和内皮细胞的潜力。在与松散胚胎间充质组织中许多造血区域相同的主动脉旁区域观察到散在的CD45 +细胞。在胚胎第6天胸腺定植之前检测到表达CD8α（单克隆抗体3 - 298）的造血细胞。在IEM前体的流式细胞术分析中，表达Ov、CD45和CD8α的细胞似乎形成不同的亚群，表明这些造血细胞具有异质性。
