Department of Pharmacology & Toxicology, Boonshoft School of Medicine, Wright State University, 206 Health Sciences Bldg., 3640 Colonel Glenn Hwy., Dayton, Ohio 45435, USA.
Nanoscale. 2013 May 7;5(9):3747-56. doi: 10.1039/c3nr30071d. Epub 2013 Mar 18.
Gold nanoparticles (Au-NPs) have been designated as superior tools for biological applications owing to their characteristic surface plasmon absorption/scattering and amperometric (electron transfer) properties, in conjunction with low or no immediate toxicity towards biological systems. Many studies have shown the ease of designing application-based tools using Au-NPs but the interaction of this nanosized material with biomolecules in a physiological environment is an area requiring deeper investigation. Immune cells such as lymphocytes circulate through the blood and lymph and therefore are likely cellular components to come in contact with Au-NPs. The main aim of this study was to mechanistically determine the functional impact of Au-NPs on B-lymphocytes. Using a murine B-lymphocyte cell line (CH12.LX), treatment with citrate-stabilized 10 nm Au-NPs induced activation of an NF-κB-regulated luciferase reporter, which correlated with altered B lymphocyte function (i.e. increased antibody expression). TEM imaging demonstrated that Au-NPs can pass through the cellular membrane and therefore could interact with intracellular components of the NF-κB signaling pathway. Based on the inherent property of Au-NPs to bind to -thiol groups and the presence of cysteine residues on the NF-κB signal transduction proteins IκB kinases (IKK), proteins specifically bound to Au-NPs were extracted from CH12.LX cellular lysate exposed to 10 nm Au-NPs. Electrophoresis identified several bands, of which IKKα and IKKβ were immunoreactive. Further evaluation revealed activation of the canonical NF-κB signaling pathway as evidenced by IκBα phosphorylation at serine residues 32 and 36 followed by IκBα degradation and increased nuclear RelA. Additionally, expression of an IκBα super-repressor (resistant to proteasomal degradation) reversed Au-NP-induced NF-κB activation. Altered NF-κB signaling and cellular function in B-lymphocytes suggests a potential for off-target effects with in vivo applications of gold nanomaterials and underscores the need for more studies evaluating the interactions of nanomaterials with biomolecules and cellular components.
金纳米粒子（Au-NPs）因其独特的表面等离子体吸收/散射和安培（电子转移）特性以及对生物系统的低毒性或无毒性而被指定为生物应用的优越工具。许多研究表明，使用 Au-NPs 设计基于应用的工具非常容易，但这种纳米材料与生理环境中的生物分子的相互作用是一个需要更深入研究的领域。淋巴细胞等免疫细胞在血液和淋巴中循环，因此很可能是与 Au-NPs 接触的细胞成分。本研究的主要目的是从机制上确定 Au-NPs 对 B 淋巴细胞的功能影响。使用鼠 B 淋巴细胞细胞系（CH12.LX），用柠檬酸稳定的 10nm Au-NPs 处理诱导 NF-κB 调控的荧光素酶报告基因的激活，这与 B 淋巴细胞功能的改变（即抗体表达增加）相关。TEM 成像表明 Au-NPs 可以穿过细胞膜，因此可以与 NF-κB 信号转导途径的细胞内成分相互作用。基于 Au-NPs 与 -巯基结合的固有特性和 NF-κB 信号转导蛋白 IκB 激酶（IKK）上半胱氨酸残基的存在，从暴露于 10nm Au-NPs 的 CH12.LX 细胞裂解物中提取与 Au-NPs 特异性结合的蛋白质。电泳鉴定出几条带，其中 IKKα 和 IKKβ 具有免疫反应性。进一步评估表明，NF-κB 信号通路的经典途径被激活，证据是丝氨酸残基 32 和 36 上的 IκBα 磷酸化，随后 IκBα 降解和核 RelA 增加。此外，表达 IκBα 超抑制剂（对蛋白酶体降解有抗性）逆转了 Au-NP 诱导的 NF-κB 激活。B 淋巴细胞中 NF-κB 信号和细胞功能的改变表明，金纳米材料体内应用可能存在脱靶效应，并强调需要更多研究来评估纳米材料与生物分子和细胞成分的相互作用。
