Department of Pathogenic Biology and Immunology, Guangzhou Medical University, 510182, Guangzhou, China,
Parasitol Res. 2014 Mar;113(3):1001-9. doi: 10.1007/s00436-013-3732-5. Epub 2013 Dec 10.
The mesenteric lymph node (MLN) is the main draining lymph node in mouse enterocoelia, which contains many types of immune cells. Among these cells, natural killer (NK) and natural killer T (NKT) cells belong to innate lymphoid cells (ILCs), which have potent activities for controlling a variety of pathogenic infections. In this study, C57BL/6 mice were infected with Schistosoma japonicum for 5-7 weeks. Lymphocytes were isolated from the MLN to detect changes in the phenotype and function of NK and NKT cells using a fluorescence activating cell sorter (FACS). These results demonstrated that a S. japonicum infection could significantly increase the percentage of NK cells in the mouse MLN, (P < 0.05). We found an increase in the cell number of both NK and NKT cells. In addition, we found that NK and NKT cells from infected mice expressed higher levels of CD69 compared to normal mice (P < 0.05). These results demonstrated that a S. japonicum infection could induce MLN NK and NKT cell activation. Moreover, we found that the expression of CD4 was increased in infected MLN NK cells (P < 0.05). Furthermore, intracellular cytokine staining revealed that expression of IL-4 and IL-17 were significantly enhanced in both the NK and NKT cells of infected mice after phorbol 12-myristate 13-acetate (PMA) and ionomycin stimulation (P < 0.05). Taken together, these results indicated that infection-induced MLN NK and NKT cells might play roles in modulating the classical T cell response. Finally, our results indicated that the expression of CD94 was decreased in NK cells, suggesting that the downregulation of CD94 expression might served as a mechanism in NK cell activation.
肠系膜淋巴结（MLN）是小鼠肠腔的主要引流淋巴结，其中包含许多类型的免疫细胞。在这些细胞中，自然杀伤（NK）和自然杀伤 T（NKT）细胞属于先天淋巴细胞（ILC），它们具有控制多种致病感染的强大活性。在这项研究中，C57BL/6 小鼠感染日本血吸虫 5-7 周。从 MLN 中分离淋巴细胞，使用荧光激活细胞分选仪（FACS）检测 NK 和 NKT 细胞表型和功能的变化。结果表明，日本血吸虫感染可显著增加小鼠 MLN 中 NK 细胞的百分比（P < 0.05）。我们发现 NK 和 NKT 细胞的细胞数均增加。此外，我们发现感染小鼠的 NK 和 NKT 细胞表达的 CD69 水平高于正常小鼠（P < 0.05）。这些结果表明，日本血吸虫感染可诱导 MLN NK 和 NKT 细胞激活。此外，我们发现感染 MLN NK 细胞中 CD4 的表达增加（P < 0.05）。此外，细胞内细胞因子染色显示，在用佛波醇 12-肉豆蔻酸 13-乙酸酯（PMA）和离子霉素刺激后，感染小鼠的 NK 和 NKT 细胞中 IL-4 和 IL-17 的表达显著增强（P < 0.05）。综上所述，这些结果表明感染诱导的 MLN NK 和 NKT 细胞可能在调节经典 T 细胞反应中发挥作用。最后，我们的结果表明 NK 细胞中 CD94 的表达降低，提示 CD94 表达的下调可能是 NK 细胞激活的一种机制。
