Abstract:
This study investigates immune priming effects associated with granulocytes in crickets through a comprehensive analysis. Kaplan-Meier survival analysis reveals a significant contrast in survival rates, with the heat-killed Bacillus thuringiensis (Bt)-primed group exhibiting an impressive ~80% survival rate compared to the PBS buffer-primed group with only ~10% survival 60 hours post live Bt infection. Hemocyte analysis underscores elevated hemocyte counts, particularly in granulocytes of the killed Bt-primed group, suggesting a correlation between the heat-killed Bt priming and heightened immune activation. Microscopy techniques further explore granulocyte morphology, unveiling distinctive immune responses in the killed Bt-primed group characterized by prolonged immune activation, heightened granulocyte activity, phagocytosis, and extracellular trap formation, contributing to enhanced survival rates. In particular, after 24 hours of injecting live Bt, most granulocytes in the PBS buffer-primed group exhibited extracellular DNA trap cell death (ETosis), while in the killed Bt-primed group, the majority of granulocytes were observed to maintain highly activated extracellular traps, sustaining the immune response. Gene expression analysis supports these findings, revealing differential regulation of immune-related genes such as antibacterial humoral response, detection of bacterial lipopeptides, and cellular response to bacteria lipopeptides. Additionally, the heat-killed Bt-primed group, the heat-killed E. coli-primed group, and the PBS-primed group were re-injected with live Bt 2 and 9 days post priming. Two days later, only the PBS-primed group displayed low survival rates. After injecting live Bt 9 days later, the heat-killed E. coli-primed group surprisingly showed a similarly low survival rate, while the heat-killed Bt-primed group exhibited a high survival rate of ~60% after 60 hours, with actively moving and healthy crickets. In conclusion, this research provides valuable insights into both short-term and long-term immune priming effects in crickets, contributing to our understanding of invertebrate immunity with potential applications in public health.
摘要:
本研究通过综合分析研究了与the中粒细胞相关的免疫引发作用。Kaplan-Meier生存分析揭示了生存率的显著对比,与PBS缓冲液引发的组相比,热灭活的苏云金芽孢杆菌(Bt)引发的组表现出令人印象深刻的〜80%的存活率,在活的Bt感染后60小时存活率仅为〜10%。血细胞分析强调血细胞计数升高,特别是在被杀死的Bt-primed组的粒细胞中,表明热灭活的Bt引发与增强的免疫激活之间存在相关性。显微镜技术进一步探索粒细胞形态,在以长期免疫激活为特征的被杀死的Bt-primed组中揭示了独特的免疫反应,粒细胞活动增强,吞噬作用,和细胞外陷阱的形成,有助于提高生存率。特别是,注射Bt活24小时后,PBS缓冲液引发组中的大多数粒细胞表现出细胞外DNA陷阱细胞死亡(ETosis),在被杀的Bt-primed组,观察到大多数粒细胞维持高度激活的细胞外陷阱,维持免疫反应。基因表达分析支持这些发现,揭示了免疫相关基因的差异调节,如抗菌体液反应,细菌脂肽的检测,和细胞对细菌脂肽的反应。此外,热杀死的Bt-primed组,热杀灭大肠杆菌引发组,和PBS灌注组在灌注后2天和9天再次注射活Bt。两天后,只有PBS灌注组的生存率较低.在9天后注射活Bt后,令人惊讶的是,热灭活大肠杆菌引发组的存活率同样低,而热灭活Bt引发组60小时后的存活率约为60%,积极移动和健康的板球。总之,这项研究提供了对板球短期和长期免疫启动效应的有价值的见解,有助于我们对无脊椎动物免疫的理解,并在公共卫生中具有潜在的应用。