Xiong M, Elson G, Legarda D, Leibovich S J
Department of Anatomy, Cell Biology & Injury Sciences, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark 07103, USA.
Am J Pathol. 1998 Aug;153(2):587-98. doi: 10.1016/S0002-9440(10)65601-5.
Murine thioglycolate-induced peritoneal macrophages (MPMs) and the murine RAW264.7 macrophage-like cell line (RAW cells) constitutively produce vascular endothelial growth factor (VEGF). VEGF production is increased under hypoxic conditions or after cell activation with interferon-gamma (IFNgamma) and endotoxin (lipopolysaccharide, LPS). In contrast, tumor necrosis factor-alpha is produced only by IFNgamma/LPS-activated cells. Lactate (25 mmol/L) does not increase VEGF production by these cells. However, hypoxia, lactate, and IFNgamma/LPS-activated MPMs express angiogenic activity, whereas normoxic, nonactivated MPMs do not. Lack of angiogenic activity is not due to an antiangiogenic factor(s) in the medium of these cells. Angiogenic activity produced by hypoxia and lactate-treated MPMs is neutralized by anti-VEGF antibody, which also neutralizes most of the angiogenic activity produced by IFNgamma/LPS-activated MPMs. The inducible nitric oxide synthase inhibitors Ng-nitro-L-arginine-methyl ester (1.5 mmol/L) and aminoguanidine (1 mmol/L) block production of angiogenic activity by MPMs and RAW cells. In RAW cells, Ng-nitro-L-arginine-methyl ester and AG block IFNgamma/LPS-activated, but not constitutive, VEGF production, whereas in MPMs, neither constitutive nor IFNgamma/LPS-activated VEGF synthesis is affected. Synthesis of tumor necrosis factor-alpha is also unaffected. In contrast to normoxic, nonactivated MPMs, inducible nitric oxide synthase-inhibited, IFNgamma/LPS-activated MPMs produce an antiangiogenic factor(s). We conclude that VEGF is a major contributor to macrophage-derived angiogenic activity, and that activation by hypoxia, lactate, or IFNgamma/LPS switches macrophage-derived VEGF from a nonangiogenic to an angiogenic state. This switch may involve a posttranslational modification of VEGF, possibly by the process of ADP-ribosylation. ADP-ribosylation by MPM cytosolic extracts or by cholera toxin switches rVEGF165 from an angiogenic to a nonangiogenic state. In IFNgamma/LPS-activated MPMs, the inducible nitric oxide synthase-dependent pathway also regulates the expression of an antiangiogenic factor(s) that antagonizes the bioactivity of VEGF and provides an additional regulatory pathway controlling the angiogenic phenotype of macrophages.
小鼠巯基乙酸盐诱导的腹腔巨噬细胞（MPM）和小鼠RAW264.7巨噬细胞样细胞系（RAW细胞）可组成性地产生血管内皮生长因子（VEGF）。在缺氧条件下或用γ干扰素（IFNγ）和内毒素（脂多糖，LPS）激活细胞后，VEGF的产生会增加。相比之下，肿瘤坏死因子-α仅由IFNγ/LPS激活的细胞产生。乳酸（25 mmol/L）不会增加这些细胞的VEGF产生。然而，缺氧、乳酸以及IFNγ/LPS激活的MPM表现出血管生成活性，而常氧、未激活的MPM则没有。缺乏血管生成活性并非由于这些细胞培养基中的抗血管生成因子。缺氧和乳酸处理的MPM产生的血管生成活性可被抗VEGF抗体中和，该抗体也能中和IFNγ/LPS激活的MPM产生的大部分血管生成活性。诱导型一氧化氮合酶抑制剂Nω-硝基-L-精氨酸甲酯（1.5 mmol/L）和氨基胍（1 mmol/L）可阻断MPM和RAW细胞血管生成活性的产生。在RAW细胞中，Nω-硝基-L-精氨酸甲酯和AG可阻断IFNγ/LPS激活的而非组成性的VEGF产生，而在MPM中，组成性和IFNγ/LPS激活的VEGF合成均不受影响。肿瘤坏死因子-α的合成也不受影响。与常氧、未激活的MPM不同，诱导型一氧化氮合酶抑制的、IFNγ/LPS激活的MPM会产生一种抗血管生成因子。我们得出结论，VEGF是巨噬细胞衍生的血管生成活性的主要贡献者，并且缺氧、乳酸或IFNγ/LPS的激活可使巨噬细胞衍生的VEGF从非血管生成状态转变为血管生成状态。这种转变可能涉及VEGF的翻译后修饰，可能是通过ADP-核糖基化过程。MPM胞质提取物或霍乱毒素进行的ADP-核糖基化可使rVEGF165从血管生成状态转变为非血管生成状态。在IFNγ/LPS激活的MPM中，诱导型一氧化氮合酶依赖性途径还调节一种抗血管生成因子的表达，该因子拮抗VEGF的生物活性，并提供了另一条控制巨噬细胞血管生成表型的调节途径。
