Most organisms simultaneously face various chemical and biological stresses in the environment. Herein, we investigated how pathogen infection modifies an organism's response to chemical exposure. To explore this phenomenon, we conducted a toxicity study combined with pathogen infection by using the nematode Caenorhabditis elegans, the pathogen Pseudomonas aeruginosa, and various environmental chemicals. C. elegans preinfected with PA01, when subsequently exposed to chemicals, became sensitized to the toxicity of nonylphenol (NP) and cadmium (Cd), whereas they became tolerant to the toxicity of silver nanoparticles (AgNPs); this led us to conduct a mechanistic study focusing on AgNP exposure. A gene expression profiling study revealed that most of the immune response genes activated by PA01 infection remained activated after subsequent exposure to AgNPs, thereby suggesting that the acquired tolerance of C. elegans to AgNP exposure may be due to boosted immunity resulting from PA01 preinfection. Further, a functional genetic analysis revealed that the immune response pathway (i.e., PMK-1/p38 MAPK) was involved in defense against AgNP exposure in PA01-preinfected C. elegans, thus suggesting immune and stress response crosstalk to xenobiotic exposure. This study will aid in the elucidation of how pathogen infection impacts the way the defense system responds to subsequent xenobiotic exposure.

大多数生物同时会在环境中面临各种化学和生物压力。在这里，我们调查了病原体感染如何改变生物体对化学暴露的反应。为了探索这种现象，我们通过使用线虫秀丽隐杆线虫，铜绿假单胞菌和各种环境化学物质进行了结合病原体感染的毒性研究。秀丽隐杆线虫预感染了PA01的药物随后暴露于化学药品中时，变得对壬基酚（NP）和镉（Cd）的毒性敏感，而对银纳米颗粒（AgNPs）的毒性具有耐受性；这导致我们进行了针对AgNP暴露的机理研究。基因表达谱研究表明，PA01感染激活的大多数免疫反应基因在随后暴露于AgNPs后仍保持激活状态，从而表明秀丽隐杆线虫对AgNP暴露获得的耐受性可能是由于PA01预先感染导致免疫力增强所致。此外，功能基因分析表明，免疫反应途径（即PMK-1 / p38 MAPK）参与了针对PA01预感染秀丽隐杆线虫中AgNP暴露的防御。，因此暗示对异源生物的暴露会产生免疫和压力反应串扰。这项研究将有助于阐明病原体感染如何影响防御系统对随后的异源生物暴露的反应方式。