Key Laboratory of Livestock Infectious Diseases, Ministry of Education, Shenyang Agricultural University, Liaoning Province, Shenyang, 110866, People's Republic of China.
Animal Husbandry and Veterinary Research Institute, Beijing Academy of Agriculture and Forestry Sciences, Beijing, People's Republic of China.
Sci Rep. 2022 Mar 9;12(1):4181. doi: 10.1038/s41598-022-08180-6.
Infection with Brucella is characterized by the inhibition of host immune responses. MicroRNA-155 (miR-155) has been implicated in the immune response to many diseases. In this study, its expression during Brucella 16M infection of macrophages and mice was analyzed. Expression of miR-155 was significantly induced in macrophages at 24 h post infection. Further, an analysis of infected mice showed that miR-155 was inhibited at 7 and 14 days but induced at 28 days. Interestingly, this trend in induction or inhibition was reversed at 7 and 14 days in 16M△virB-infected mice. This suggested that decreased expression of miR-155 at an early stage of infection was dependent on intracellular replication. In humans with brucellosis, serum levels of miR-155 were significantly decreased compared to those in individuals without brucellosis and healthy volunteers. Significant correlations were observed between serum level of miR-155 and serum anti-Brucella antibody titers and the sweating symptom. This effect suggests that Brucella interferes with miR-155-regulated immune responses via a unique mechanism. Taken together, data from this study indicate that Brucella infection affects miR-155 expression and that human brucellosis patients show decreased serum levels of miR-155.
布鲁氏菌感染的特征是抑制宿主的免疫反应。MicroRNA-155（miR-155）已被牵涉到许多疾病的免疫反应中。在本研究中，分析了巨噬细胞和小鼠感染布鲁氏菌 16M 时 miR-155 的表达情况。感染后 24 小时，巨噬细胞中 miR-155 的表达显著诱导。此外，对感染小鼠的分析表明，miR-155 在第 7 和 14 天受到抑制，但在第 28 天被诱导。有趣的是，在 16M△virB 感染的小鼠中，这种诱导或抑制的趋势在第 7 和 14 天发生逆转。这表明在感染早期 miR-155 的表达减少依赖于细胞内复制。与没有布鲁氏菌病和健康志愿者相比，患有布鲁氏菌病的患者血清 miR-155 水平显著降低。血清 miR-155 水平与血清抗布鲁氏菌抗体滴度和出汗症状之间存在显著相关性。这种效应表明布鲁氏菌通过独特的机制干扰 miR-155 调节的免疫反应。总之，本研究的数据表明布鲁氏菌感染影响 miR-155 的表达，人类布鲁氏菌病患者的血清 miR-155 水平降低。
