Department of Invertebrate Immunology, Maria Curie-Sklodowska University, Akademicka 19, 20-033 Lublin, Poland.
J Invertebr Pathol. 2011 May;107(1):16-26. doi: 10.1016/j.jip.2010.12.015. Epub 2011 Jan 12.
The role of Pseudomonas aeruginosa elastase B in activation of the humoral immune response in Galleria mellonella larvae was investigated. The results of our study showed that elastase B injected at a sublethal concentration was responsible for eliciting the humoral immune response in G. mellonella larvae. The insects exhibited increased antibacterial activity, namely, we observed appearance of antimicrobial peptides and a higher level of lysozyme in cell-free hemolymph. Elastase B seems to be a more potent elicitor than thermolysin because similar maximal antibacterial activity levels were observed at a 5-fold lower concentration. We also demonstrated that there were differences in the kinetics of induction of antimicrobial activity between thermolysin and elastase B. The maximum level was observed 18h post challenge of thermolysin and 38h after injection of elastase B. It was also shown that, 24h after elastase injection, the relative levels of apoLp-III in the hemolymph significantly increased in comparison with control G. mellonella larvae. The activation of immune responses in metalloproteinase-challenged larvae involved synthesis of metalloproteinase inhibitors which increased the survival rates of insects both against the lethal dose of thermolysin as well as against viable pathogenic bacterial cells of P. aeruginosa.
我们研究了绿脓杆菌弹性蛋白酶 B 在诱导家蚕幼虫体液免疫反应中的作用。研究结果表明，以亚致死浓度注射的弹性蛋白酶 B 负责诱导家蚕幼虫的体液免疫反应。昆虫表现出增强的抗菌活性，即在无细胞血淋巴中观察到抗菌肽的出现和溶菌酶水平的升高。弹性蛋白酶 B 似乎比胰蛋白酶更有效，因为在低 5 倍的浓度下观察到类似的最大抗菌活性水平。我们还证明了在诱导抗菌活性的动力学方面，弹性蛋白酶 B 和胰蛋白酶之间存在差异。在热稳定丝氨酸蛋白酶处理后 18 小时观察到最大水平，而在注射弹性蛋白酶 B 38 小时后。还表明，在注射弹性蛋白酶 24 小时后，与对照家蚕幼虫相比，血淋巴中的 apoLp-III 相对水平显著增加。在金属蛋白酶处理的幼虫中激活免疫反应涉及金属蛋白酶抑制剂的合成，这提高了昆虫对热稳定丝氨酸蛋白酶的致死剂量以及对绿脓假单胞菌活致病性细菌细胞的存活率。
