Lab Tissue Engineering and Skin Pathophysiology, Dermatology Institute (Istituto Dermopatico dell'Immacolata, IDI IRCCS), Rome, Italy.
Br J Pharmacol. 2009 Nov;158(5):1236-47. doi: 10.1111/j.1476-5381.2009.00401.x. Epub 2009 Sep 28.
The immunomodulatory effects of alpha-fetoprotein (AFP) on lymphocytes and macrophages have been described in vitro and in vivo. Recombinant forms of human AFP have been proposed as potential therapeutic entities for the treatment of autoimmune diseases. We examined the effects of embryonic and recombinant human AFP on the spontaneous, UVA- and cytokine-induced pro-inflammatory responses of human keratinocytes.
Cultures of primary and immortalized human keratinocytes (HaCaT) and human blood T lymphocytes were used. The effects of AFP on cytokine expression were studied by bioplexed elisa and quantitative reverse transcriptase polymerase chain reaction assay. Kinase and nuclear factor kappa B (NFkappaB) phosphorylation were quantified by intracellular elisa. Nuclear activator protein 1 and NFkappaB DNA binding activity was measured by specific assays. Nitric oxide and H(2)O(2) production and redox status were assessed by fluorescent probe and biochemical methods.
All forms of AFP enhanced baseline expression of cytokines, chemokines and growth factors. AFP dose-dependently increased tumour necrosis factor alpha-stimulated granulocyte macrophage colony stimulating factor and interleukin 8 expression and decreased tumour necrosis factor alpha-induced monocyte chemotactic protein 1 and IP-10 (interferon gamma-produced protein of 10 kDa) expression. AFP induced a marked activator protein 1 activation in human keratinocytes. AFP also increased H(2)O(2) and modulated nitrite/nitrate levels in non-stimulated keratinocytes whereas it did not affect these parameters or cytokine release from UVA-stimulated cells. Phosphorylation of extracellular signal-regulated kinase (ERK1/2) and Akt1 but not NFkappaB was activated by AFP alone or by its combination with UVA.
Exogenous AFP induces activation of human keratinocytes, with de novo expression of a number of pro-inflammatory mediators and modulation of their pro-inflammatory response to cytokines or UVA. AFP may modulate inflammatory events in human skin.
α-胎蛋白（AFP）对淋巴细胞和巨噬细胞的免疫调节作用已在体外和体内得到描述。人 AFP 的重组形式已被提议作为治疗自身免疫性疾病的潜在治疗实体。我们研究了胚胎和重组人 AFP 对人角质形成细胞自发、UVA 和细胞因子诱导的促炎反应的影响。
使用原代和永生化人角质形成细胞（HaCaT）和人血 T 淋巴细胞培养物。通过生物多元 ELISA 和定量逆转录聚合酶链反应测定法研究 AFP 对细胞因子表达的影响。通过细胞内 ELISA 定量激酶和核因子 kappa B（NFkappaB）磷酸化。通过特定测定法测量核激活蛋白 1 和 NFkappaB DNA 结合活性。通过荧光探针和生化方法评估一氧化氮和 H₂O₂产生和氧化还原状态。
所有形式的 AFP 均增强了细胞因子、趋化因子和生长因子的基础表达。AFP 呈剂量依赖性增加肿瘤坏死因子-α刺激的粒细胞巨噬细胞集落刺激因子和白细胞介素 8 的表达，并降低肿瘤坏死因子-α诱导的单核细胞趋化蛋白 1 和 IP-10（干扰素 γ产生的 10 kDa 蛋白）的表达。AFP 在人角质形成细胞中诱导明显的激活蛋白 1 激活。AFP 还增加了非刺激角质形成细胞中的 H₂O₂并调节亚硝酸盐/硝酸盐水平，而对 UVA 刺激细胞中的这些参数或细胞因子释放没有影响。单独或与 UVA 联合使用 AFP 可激活细胞外信号调节激酶（ERK1/2）和 Akt1 的磷酸化，但不激活 NFkappaB。
外源性 AFP 诱导人角质形成细胞激活，新表达多种促炎介质，并调节其对细胞因子或 UVA 的促炎反应。AFP 可能调节人皮肤中的炎症事件。
