Delia D, Lampugnani M G, Resnati M, Dejana E, Aiello A, Fontanella E, Soligo D, Pierotti M A, Greaves M F
Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy.
Blood. 1993 Feb 15;81(4):1001-8.
Freshly cultured vascular endothelial cells express the CD34 antigen in a diffuse cell surface pattern with some concentration on microvilli. Expression is downregulated with proliferation in continuous culture and undetectable after nine population doublings but can be maintained by restraining cell proliferation and promoting cell contact. Expression of CD34 at the antigen and mRNA levels on early passage cells is rapidly downregulated by interleukin-1 beta (IL-1 beta), interferon-gamma (INF-gamma), and tumor necrosis factor-alpha (TNF-alpha) under conditions in which these ligands upregulate the adhesion molecules: endothelial leukocyte adhesion molecule 1 (ELAM-1) and intracellular adhesion molecule 1 (ICAM-1). This reciprocal pattern of expression and the topographic distribution of CD34 molecules on the lumenal interdigitated microprocesses of adjacent endothelial cells in vivo suggest that CD34 might have a negative modulating role on adhesion functions of endothelia.
新鲜培养的血管内皮细胞以弥漫性细胞表面模式表达CD34抗原，在微绒毛上有一定浓度。在连续培养中，随着细胞增殖，其表达下调，在九次群体倍增后无法检测到，但可通过抑制细胞增殖和促进细胞接触来维持。在早期传代细胞中，在这些配体上调黏附分子（内皮白细胞黏附分子1（ELAM-1）和细胞间黏附分子1（ICAM-1））的条件下，白细胞介素-1β（IL-1β）、干扰素-γ（INF-γ）和肿瘤坏死因子-α（TNF-α）会迅速下调抗原和mRNA水平上的CD34表达。这种表达的相互模式以及体内相邻内皮细胞腔面指状微突起上CD34分子的拓扑分布表明，CD34可能对内皮细胞的黏附功能具有负调节作用。
