Marin M L, Murtha J, Dong W, Pestka J J
Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824-1224, USA.
J Toxicol Environ Health. 1996 Jul;48(4):379-96. doi: 10.1080/009841096161267.
The thymoma cell line EL4.IL-2 (EL-4) was used as a T-cell model to assess the immunotoxic effects of several mycotoxins produced by the Aspergillus-Penicillium and the Fusarium groups. EL-4 cells were stimulated with phorbol 12-myristate 12-acetate (PMA) in the presence of mycotoxins at various concentrations for 5 d and culture supernatants were analyzed for interleukins (IL) IL-2 and IL-5 by enzyme-linked immunosorbent assay (ELISA). The cytokine effects were further related to proliferation and cell viability using the MTT [3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide] assay with absorbance at 570 nm (A570) as the endpoint indicator. IL-2 and IL-5 levels were dramatically increased by cyclopiazonic acid at 50-1000 ng/ml, whereas IL-2 was significantly decreased at 10 microgram/ml. Proliferation was slightly increased at 100-1000 ng/ml cyclopiazonic acid but markedly depressed at 5 and 10 microgram/ml. When EL-4 cells were exposed to 5 and 10 microgram/ml of ochratoxin A, IL-2 production was markedly increased while IL-5 production was significantly decreased. The A570 was significantly decreased by ochratoxin A at 10 microgram/ml. IL-2 and Il-5 production was almost totally suppressed by patulin at concentrations > or = 500 ng/ml and by T-2 toxin at > or = 5 ng/ml. These effects occurred concurrently with marked depression of A570 in the MTT assay. Although A570 was unaffected by either zearalenone or alpha-zearalenol exposure, both IL-2 and IL-5 levels were significantly elevated by these toxins at 5 or 10 microgram/ml. IL-2 and IL-5 production were not affected in EL-4 cells cultured with either the Aspergillus-Penicillium toxins aflatoxin B1 and secalonic acid or the Fusarium toxins wortmannin, fumonisin B1, or fusaric acid at concentrations up to 10 microgram/ml. In total, the EL-4 culture studies indicated that cyclopiazonic acid, ochratoxin A, zearalenone, and alpha-zearalenol could stimulate cytokine production whereas patulin and T-2 toxin were inhibitory. Cytokine dysregulation was not always related directly to perturbations in proliferation. The results suggest that the EL-4 thymoma cell line could be a simple and effective in vitro model for evaluating immunotoxicity of various classes of environmental chemicals.
胸腺oma细胞系EL4.IL-2（EL-4）被用作T细胞模型，以评估由曲霉-青霉属和镰刀菌属产生的几种霉菌毒素的免疫毒性作用。在存在不同浓度霉菌毒素的情况下，用佛波酯12-肉豆蔻酸13-乙酸酯（PMA）刺激EL-4细胞5天，然后通过酶联免疫吸附测定（ELISA）分析培养上清液中的白细胞介素（IL）IL-2和IL-5。使用MTT [3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四氮唑溴盐]测定法，以570 nm处的吸光度（A570）作为终点指标，进一步将细胞因子的作用与增殖和细胞活力相关联。环匹阿尼酸在50-1000 ng/ml时可显著提高IL-2和IL-5水平，而在10 μg/ml时IL-2则显著降低。环匹阿尼酸在100-1000 ng/ml时增殖略有增加，但在5和10 μg/ml时则明显受到抑制。当EL-4细胞暴露于5和10 μg/ml的赭曲霉毒素A时，IL-2的产生显著增加，而IL-5的产生则显著减少。赭曲霉毒素A在10 μg/ml时可使A570显著降低。棒曲霉素在浓度≥500 ng/ml时以及T-2毒素在≥5 ng/ml时几乎完全抑制了IL-2和IL-5的产生。这些作用与MTT测定中A570的显著降低同时发生。尽管玉米赤霉烯酮或α-玉米赤霉烯醇的暴露对A570没有影响，但这两种毒素在5或10 μg/ml时均可显著提高IL-2和IL-5水平。在浓度高达10 μg/ml的情况下，用曲霉-青霉属毒素黄曲霉毒素B1和secalonic酸或镰刀菌属毒素渥曼青霉素、伏马菌素B1或镰刀菌酸培养EL-4细胞时，IL-2和IL-5的产生不受影响。总的来说，EL-4培养研究表明，环匹阿尼酸、赭曲霉毒素A、玉米赤霉烯酮和α-玉米赤霉烯醇可刺激细胞因子的产生，而棒曲霉素和T-2毒素则具有抑制作用。细胞因子失调并不总是与增殖的扰动直接相关。结果表明，EL-4胸腺oma细胞系可能是评估各类环境化学物质免疫毒性的一种简单有效的体外模型。
