Data from: Chronic exposure to a neonicotinoid increases expression of antimicrobial peptide genes in the bumblebee Bombus impatiens

Bumblebees are important pollinators in wild and agricultural settings. In recent decades pollinator declines have been linked to the effects of increased pesticide use and the spread of disease. Synergy between these factors has been suggested, but no physiological mechanism has been identified. This study examines the connection between neonicotinoid exposure and innate immune function in the bumblebee Bombus impatiens, which is an important wild and commercial pollinator in eastern North America. Experimental colonies in the field were enclosed and provided pollen and sugar syrup containing an agriculturally relevant range of imidacloprid concentrations. Bumblebees were collected from colonies over four weeks, and the expression of antimicrobial peptides was measured using multiplex quantitative real time PCR. Significant increases in the expression of abaecin, apidaecin and hymenoptaecin were found over time in treatments receiving moderate to high concentrations of the pesticide. Responses were dependent on time of exposure and dose. These results indicate that immune function in bumblebees is affected by neonicotinoid exposure and suggest a physiological mechanism by which neonicotinoids may impact the innate immune function of bumblebee pollinators in wild and agricultural habitats.熊蜂 (Bumblebee) 是野生与农业生境中重要的传粉昆虫。近数十年来，传粉者种群衰退与农药使用量增加及疾病传播密切相关。已有研究提出上述两类因素存在协同效应，但尚未明确其背后的生理机制。本研究针对北美东部地区重要的野生与商业传粉昆虫——熊蜂 (Bombus impatiens)，探讨了新烟碱类杀虫剂 (neonicotinoid) 暴露与先天免疫功能之间的关联。野外实验蜂群被置于封闭笼舍中，饲喂含有农业生产相关浓度梯度吡虫啉 (imidacloprid) 的花粉与蔗糖糖浆。研究人员在四周的实验周期内，定期从各蜂群中采集熊蜂样本，并采用多重实时荧光定量PCR (multiplex quantitative real-time PCR) 检测抗菌肽的表达量。在暴露于中等至高浓度吡虫啉的处理组中，阿巴肽 (abaecin)、蜜蜂抗菌肽 (apidaecin) 与膜翅抗菌肽 (hymenoptaecin) 的表达量随时间推移均出现显著升高，且免疫应答水平取决于暴露时长与药剂剂量。上述结果表明，熊蜂的免疫功能会受到新烟碱类杀虫剂暴露的影响，同时揭示了新烟碱类杀虫剂可通过该生理机制，对野生与农业生境中熊蜂传粉者的先天免疫功能产生影响。