The network of immune system and nerve system in host defense to bacterial infections

免疫系统、神经系统和内分泌系统之间形成了网络。我们对细菌感染中免疫系统和神经系统之间的相互作用很感兴趣。选择P物质(SP)、血管活性肠肽(VIP)等神经肽作为神经系统参数。用免疫组织化学方法研究了单核细胞增生性李斯特氏菌和拟新陈代谢李斯特氏菌对小鼠肝脏SP和VIP的诱导作用。在感染李斯特氏菌的小鼠肝脏的血管周围和周围的浸润性细胞中均未检测到SP，而VIP则呈阳性反应。与之相反，在钩端螺旋体感染小鼠的肝脏肉芽肿样病变中检测到SP，而不是VIP。这些结果提示，SP和VIP的选择性诱导可能取决于感染的细菌，神经肽可能是由炎症细胞分泌的。在逆转录-聚合酶链式反应的研究中，PropreVIP基因的表达与李斯特氏菌在肝脏中的生长同步，这些结果表明神经肽可能参与了细菌感染的炎症过程和/或宿主防御。

The network is formed between immune system, nerve system, and endocrine system. We were interested in the interaction between immune system and nerve system in bacterial infections. We chose the neuropeptides such as substance P (SP) and vasoactive intestinal peptide (VIP) as the parameter of nerve system. We investigated the induction of SP and VIP en the livers of mice which were infected intravenously with Listeria monocytogenes or Tsukamullela paurometabolum.In the studies using an immunohistochemical technique, neither SP nor VIP was detected in the livers of uninfected mice. VIP,but not SP was detected around the blood vessels and in the surrounding infiltrating cells of livers obtained from Listeria-infected mice. In contrast, SP,but not VIP,was detected in the granuloma-like lesions of livers obtained from Tsukamullela-infected mice. These result suggest that the selective induction of SP and VIP might occur, depending on bacteria infected, and that the neuropeptides might be secreted by the inflammatory cells. In the studies using reverse transcription-PCR,propre VIP mRNA was induced in parallel with the growth of Listeria cells in the livers.These results demonstrate that the neuropeptides might be involved in the inflammatory process and/or the host defense in bacterial infections.