Silica binds serum proteins resulting in a shift of the dose-response for silica-induced chemokine expression in an alveolar type II cell line
Silica binds serum proteins resulting in a shift of the dose-response for silica-induced chemokine expression in an alveolar type II cell line
复制标题
DOI：
10.1006/taap.1999.8793
复制
发表时间：
1999-12-01
影响因子：
3.8
通讯作者：
Finkelstein, JN
中科院分区：
文献类型：
--
作者：
Barrett, EG;Johnston, C;Finkelstein, JN
人们越来越关注体外使用的无数培养条件、细胞系以及非纤维和纤维颗粒的剂量是否真正代表体内颗粒暴露情况的复杂环境。使用血清作为培养细胞的生长培养基的补充是广泛接受的实践，然而，关于各种血清蛋白是否可以与颗粒表面相互作用，从而改变它们在体内观察到的毒性、炎性性质或纤维形成性等，知之甚少。使用小鼠肺泡II型细胞系，MLE-15，我们测量了各种趋化因子mRNA的早期变化后，暴露于二氧化硅（方石英）的存在或不存在血清的细胞。分离总mRNA，并在颗粒暴露6小时后使用RNA酶保护测定法进行测定。我们观察到在培养基中加入血清降低了MLE-15细胞中二氧化硅诱导的体外趋化因子反应（即，剂量-反应曲线的移动）。此外，使用蛋白质印迹分析和蛋白质测序技术，我们已经确定了一个特定的血清成分，载脂蛋白-Al（载脂蛋白-Al），作为血清中的蛋白质，选择性结合二氧化硅，从而导致改变趋化因子的反应。我们还发现ape-Al不仅与二氧化硅结合，而且与其他非纤维和纤维颗粒（如二氧化钛和石棉）结合。这些结果表明，在进行体外颗粒暴露研究时，培养条件对改变实验结果的重要性。(C)北京：科学出版社.
There is a growing concern about whether the myriad of culture conditions, cell lines, and doses of nonfibrous and fibrous particles used in vitro are truly representative of the complex environment of the in viva particle exposure situation, The use of serum as a supplement to the growth medium of cultured cells is a widely accepted practice, However, little is known about whether the various serum proteins may interact with the surfaces of particles, consequently altering their toxicity, inflammatory properties, or fibrogenicity, etc. observed in vivo. Using a murine alveolar type II cell line, MLE-15, we measured the early changes in various chemokine mRNA species following exposure of the cells to silica (cristobalite) in the presence or absence of serum. Total mRNA was isolated and assayed using an RNase protection assay after 6 h of particle exposure. We observed that the addition of serum to the culture media reduced the in vitro silica-induced chemokine response (i.e,, shift in the dose-response curve) in MLE-15 cells. Further, using Western blot analysis and protein sequencing techniques, we have identified a specific serum component, apolipoprotein-Al (apo-Al), as a protein in serum that binds selectively to silica, thus leading to the altered chemokine response. We also found that ape-Al not only binds to silica but also binds to other nonfibrous and fibrous particles such as titanium dioxide and asbestos, These results demonstrate the importance of culture conditions for modifying the outcome of an experiment when performing in vitro particle exposure studies. (C) 1999 Academic Press.