Hirose K, Nishimura H, Matsuguchi T, Yoshikai Y
Laboratory of Host Defense and Germfree Life, Research Institute for Disease Mechanism and Control, Nagoya University School of Medicine, Japan.
J Leukoc Biol. 1999 Sep;66(3):382-90. doi: 10.1002/jlb.66.3.382.
Interleukin (IL)-15 is a novel cytokine with growth factor activity for T cells, B cells, and natural killer cells (NK cells). We investigated the role of IL-15 in the host defense against infection with avirulent Salmonella choleraesuis strain 31N-1 cured of 50-kb virulent plasmid. IL-15 was abundantly expressed at transcription and protein levels in macrophages infected with S. choleraesuis 31N-1. The number of NK cells in the infected sites was increased during the course of infection coincident with IL-15 production. Anti-IL-15 mAb administration inhibited the emergence of NK cells and interferon-gamma (IFN-gamma) production in serum after infection with S. choleraesuis 31N-1 and concurrently impaired the clearance of the bacteria. These results suggested that IL-15 might be responsible for protection against avirulent S. choleraesuis infection at early stage of infection through activation of NK cells in the infected sites.
白细胞介素（IL）-15是一种对T细胞、B细胞和自然杀伤细胞（NK细胞）具有生长因子活性的新型细胞因子。我们研究了IL-15在宿主抵御无毒猪霍乱沙门氏菌31N-1（已治愈50 kb毒性质粒）感染中的作用。在感染猪霍乱沙门氏菌31N-1的巨噬细胞中，IL-15在转录和蛋白质水平均大量表达。在感染过程中，感染部位NK细胞的数量随着IL-15的产生而增加。给予抗IL-15单克隆抗体可抑制感染猪霍乱沙门氏菌31N-1后血清中NK细胞的出现和干扰素-γ（IFN-γ）的产生，同时损害细菌的清除。这些结果表明，IL-15可能通过激活感染部位的NK细胞，在感染早期对无毒猪霍乱沙门氏菌感染起到保护作用。
