Pseudomonas aeruginosa infection continues to be a major threat to global public health, and new safe and efficacious vaccines are needed for prevention of infections caused by P. aeruginosa. X-ray irradiation has been used to prepare whole-cell inactivated vaccines against P. aeruginosa infection. However, the immunological mechanisms of X-ray-inactivated vaccines are still unclear and require further investigation. Our previous study found that an X-ray-inactivated whole-cell vaccine could provide protection against P. aeruginosa by boosting T cells. The aim of the present study was to further explore the immunological mechanisms of the vaccine. Herein, P. aeruginosa PAO1, a widely used laboratory strain, was utilized to prepare the vaccine, and we found nucleic acids and 8-hydroxyguanosine in the supernatant of X-ray-inactivated PAO1 (XPa). By detecting CD86, CD80, and MHCII expression, we found that XPa fostered dentritic cell (DC) maturation by detecting. XPa stimulated the cGAS-STING pathway as well as Toll-like receptors in DCs in vitro, and DC finally underwent apoptosis and pyroptosis after XPa stimulation. In addition, DC stimulated by XPa induced CD8⁺ T-cell proliferation in vitro and generated immunologic memory in vivo. Moreover, XPa vaccination induced both Th1 and Th2 cytokine responses in mice and reduced the level of inflammatory factors during infection. XPa protected mice in pneumonia models from infection with PAO1 or multidrug-resistant clinical isolate W9. Chronic obstructive pulmonary disease (COPD) mice immunized with XPa could resist PAO1 infection. Therefore, a new mechanism of an X-ray-inactivated whole-cell vaccine against P. aeruginosa infection was discovered in this study.

铜绿假单胞菌感染仍然是全球公共卫生的主要威胁，需要新的安全有效的疫苗来预防由铜绿假单胞菌引起的感染。X 射线辐照已用于制备针对铜绿假单胞菌感染的全细胞灭活疫苗。然而，X射线灭活疫苗的免疫机制仍不清楚，需要进一步研究。我们之前的研究发现，一种 X 射线灭活的全细胞疫苗可以通过增强 T 细胞来提供针对铜绿假单胞菌的保护。本研究的目的是进一步探索疫苗的免疫机制。在此，铜绿假单胞菌PAO1 是一种广泛使用的实验室菌株，用于制备疫苗，我们在 X 射线灭活的 PAO1 (XPa) 的上清液中发现了核酸和 8-羟基鸟苷。通过检测 CD86、CD80 和 MHCII 的表达，我们发现 XPa 通过检测促进了树突细胞 (DC) 的成熟。XPa 在体外刺激了 DCs 中的 cGAS-STING 通路和 Toll 样受体，在 XPa 刺激后 DC 最终发生了凋亡和细胞焦亡。此外，由 XPa 刺激的 DC 诱导 CD8 ⁺体外 T 细胞增殖并在体内产生免疫记忆。此外，XPa 疫苗接种在小鼠中诱导 Th1 和 Th2 细胞因子反应，并降低感染期间炎症因子的水平。XPa 保护肺炎模型中的小鼠免受 PAO1 或耐多药临床分离株 W9 的感染。用 XPa 免疫的慢性阻塞性肺病 (COPD) 小鼠可以抵抗 PAO1 感染。因此，本研究发现了一种抗铜绿假单胞菌感染的X射线灭活全细胞疫苗的新机制。