College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada.
Respir Res. 2021 Apr 9;22(1):104. doi: 10.1186/s12931-021-01700-4.
Workplaces with elevated organic dust levels such as animal feed barns also commonly have elevated levels of gasses, such as CO. Workers exposed to such complex environments often experience respiratory effects that may be due to a combination of respirable factors. We examined the effects of CO on lung innate immune responses in mice co-exposed to the inflammatory agents lipopolysaccharide (LPS) and organic dust. We evaluated CO levels at the building recommended limit (1000 ppm) as well as the exposure limit (5000 ppm). Mice were nasally instilled with dust extracts or LPS and immediately put into chambers with a constant flow of room air (avg. 430 ppm CO), 1000 ppm, or 5000 ppm CO enriched air. Results reveal that organic dust exposures tended to show decreased inflammatory responses with 1000 ppm CO and increased responses at 5000 ppm CO. Conversely, LPS with addition of CO as low as 1000 ppm tended to inhibit several inflammatory markers. In most cases saline treated animals showed few changes with CO exposure, though some changes in mRNA levels were present. This shows that CO as low as 1000 ppm CO was capable of altering innate immune responses to both LPS and organic dust extracts, but each response was altered in a different fashion.
工作场所中有机粉尘水平升高，如动物饲料仓，也通常会有升高的气体水平，如 CO。暴露于此类复杂环境中的工人经常会出现呼吸道影响，这可能是由于可吸入因素的组合造成的。我们研究了 CO 对同时暴露于炎症剂脂多糖（LPS）和有机粉尘的小鼠肺部固有免疫反应的影响。我们评估了建筑物推荐限值（1000 ppm）以及暴露限值（5000 ppm）下的 CO 水平。将粉尘提取物或 LPS 通过鼻腔滴注到小鼠体内，然后立即将其放入充满恒定气流的室内空气中（平均 CO 浓度为 430 ppm）、1000 ppm 或 5000 ppm CO 富化空气中。结果表明，有机粉尘暴露在 1000 ppm CO 下往往表现出炎症反应减弱，而在 5000 ppm CO 下则表现出炎症反应增强。相反，添加低至 1000 ppm 的 CO 的 LPS 往往会抑制几种炎症标志物。在大多数情况下，用 CO 暴露处理的生理盐水处理动物显示出很少的变化，尽管存在一些 mRNA 水平的变化。这表明，即使 CO 低至 1000 ppm，也能够改变对 LPS 和有机粉尘提取物的固有免疫反应，但每种反应的改变方式都不同。
