IL-20 belongs to the IL-10 family and is involved in the pathogenesis of keratinocyte hyperproliferation in vivo. Endothelial cells express IL-20 receptors. To explore the function of IL-20 on endothelial cells, we treated human umbilical vein endothelial cells (HUVECs) and human microvascular endothelial cells (HMECs) with human IL-20 and analyzed its effect on endothelial cells. IL-20 induced proliferation of endothelial cells and the activity was specifically blocked by anti-human-IL-20 monoclonal antibody and soluble (s)IL-20 receptor (R)1 and sIL-20R2. An alternatively spliced variant of IL-20 was isolated and also was shown to induce proliferation of HUVECs and HMECs. Treatment of HUVECs with both IL-10 and IL-20 demonstrated that IL-10 antagonized the activity of IL-20 because it diminished IL-20-induced proliferation of HUVECs. IL-20 significantly induced HUVECs migration and vascular tube formation on Matrigel in vitro. In vivo, IL-20 also enhanced tumor angiogenesis. Incubation of IL-20 with HUVECs induced transcripts of bFGF, VEGF, MMP-2, MMP-9, and IL-8. Furthermore, incubation of HUVECs with IL-20 induced phosphorylation of ERK1/2, p38, and JNK. Thus, IL-20 is a pleiotropic cytokine and promotes angiogenesis.

中文翻译：

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白介素20以直接和间接的方式促进血管生成。

IL-20属于IL-10家族，并参与体内角质形成细胞过度增殖的发病机理。内皮细胞表达IL-20受体。为了探索IL-20在内皮细胞上的功能，我们用人IL-20处理了人脐静脉内皮细胞（HUVEC）和人微血管内皮细胞（HMEC），并分析了其对内皮细胞的作用。IL-20诱导内皮细胞增殖，并且抗人IL-20单克隆抗体和可溶性（s）IL-20受体（R）1和sIL-20R2特异性阻断了该活性。分离了IL-20的可变剪接变体，并且还显示出其诱导HUVEC和HMEC的增殖。用IL-10和IL-20对HUVEC的处理表明IL-10拮抗IL-20的活性，因为它减少了IL-20诱导的HUVEC的增殖。IL-20显着诱导体外基质胶上HUVEC迁移和血管管形成。在体内，IL-20还增强了肿瘤血管生成。将IL-20与HUVEC一起孵育可诱导bFGF，VEGF，MMP-2，MMP-9和IL-8的转录本。此外，将HUVEC与IL-20一起孵育可诱导ERK1 / 2，p38和JNK磷酸化。因此，IL-20是多效性细胞因子，并促进血管生成。