The bioinsecticidal Cry1Ac proteins (protoxin and toxin) are potent immunogens that can activate macrophages by inducing upregulation of costimulatory molecules, pro-inflammatory cytokines, and mitogen-activated protein kinase (MAPK) signaling pathways. Besides, by the oral route, Cry1Ac toxin is mildly allergenic and induces intestinal lymphoid hyperplasia in mice. Given the potential utility of Cry1Ac protoxin as an adjuvant, as well as the human consumption of Cry1Ac toxin in transgenic crops, it is necessary to more deeply evaluate the toxicological potential of these proteins in mammalian immune cells. Here, were used in vitro evaluations in leukocyte and macrophage cell lines to test the potential toxicity of various doses of Cry1Ac proteins, by means of Alamar Blue, MTT, Annexin V, and JC1 assays. Our results indicated that neither Cry1Ac protoxin nor toxin elicited acute toxic effects, after monitoring the cell activity for 4, 8, 10, and 24 h of exposure. By flow cytometry and confocal microscopy analysis, it was observed that neither Cry1Ac toxin nor protoxin generated mitochondrial damage or depolarization or induced apoptosis or necrosis. In conclusion, despite their immunostimulatory effects, it was demonstrated that Cry1Ac proteins did not have cytotoxic effects, even at high concentrations, in primary leukocytes or macrophages or cell lines.

生物杀虫 Cry1Ac 蛋白（原毒素和毒素）是有效的免疫原，可以通过诱导共刺激分子、促炎细胞因子和丝裂原活化蛋白激酶 (MAPK) 信号通路的上调来激活巨噬细胞。此外，通过口服途径，Cry1Ac 毒素具有轻微的致敏性，可诱导小鼠肠道淋巴增生。鉴于 Cry1Ac 原毒素作为佐剂的潜在效用，以及人类在转基因作物中消耗 Cry1Ac 毒素，有必要更深入地评估这些蛋白质在哺乳动物免疫细胞中的毒理学潜力。在这里，通过 Alamar Blue、MTT、Annexin V 和 JC1 测定，在白细胞和巨噬细胞系中进行了体外评估，以测试各种剂量的 Cry1Ac 蛋白的潜在毒性。我们的结果表明，在监测暴露 4、8、10 和 24 小时的细胞活性后，Cry1Ac 原毒素和毒素均未引起急性毒性作用。通过流式细胞术和共聚焦显微镜分析，观察到 Cry1Ac 毒素和原毒素均不产生线粒体损伤或去极化或诱导细胞凋亡或坏死。总之，尽管具有免疫刺激作用，但已证明 Cry1Ac 蛋白在原代白细胞或巨噬细胞或细胞系中没有细胞毒性作用，即使在高浓度下也是如此。据观察，Cry1Ac 毒素和原毒素均不产生线粒体损伤或去极化或诱导细胞凋亡或坏死。总之，尽管具有免疫刺激作用，但已证明 Cry1Ac 蛋白在原代白细胞或巨噬细胞或细胞系中没有细胞毒性作用，即使在高浓度下也是如此。据观察，Cry1Ac 毒素和原毒素均不产生线粒体损伤或去极化或诱导细胞凋亡或坏死。总之，尽管具有免疫刺激作用，但已证明 Cry1Ac 蛋白在原代白细胞或巨噬细胞或细胞系中没有细胞毒性作用，即使在高浓度下也是如此。