Hamilton Carly A, Mahan Suman, Bell Charlotte R, Villarreal-Ramos Bernardo, Charleston Bryan, Entrican Gary, Hope Jayne C
The Roslin Institute, University of Edinburgh, Midlothian, UK.
Zoetis, Kalamazoo, MI, USA.
Immunology. 2017 May;151(1):89-97. doi: 10.1111/imm.12708. Epub 2017 Feb 7.
Natural killer (NK) cells are widely distributed in lymphoid and non-lymphoid tissues, but little is known about the recirculation of NK cells between blood and tissues. This is relevant to understanding recirculation in the steady-state and also for determining the roles for NK cells in vaccine-induced immunity and responses to infection. Therefore, the percentage of NK cells and their phenotype across peripheral blood, afferent lymph and lymph nodes in steady-state conditions was investigated in cattle using the pseudo-afferent lymphatic cannulation model. CD2 CD25 NK cells were the predominant subset of NK cells within the blood. In contrast, CD2 CD25 NK cells were the main subset present within the skin-draining afferent lymphatic vessels and lymph nodes, indicating that CD2 NK cells are the principal NK cell subset trafficking to lymph nodes via the afferent lymphatic vessel. Furthermore, a low percentage of NK cells were present in efferent lymph, which were predominantly of the CD2 subset, indicating that NK cells can egress from lymph nodes and return to circulation in steady-state conditions. These compartmentalization data indicate that NK cells represent a population of recirculating lymphocytes in steady-state conditions and therefore may be important during immune responses to vaccination or infection.
自然杀伤（NK）细胞广泛分布于淋巴组织和非淋巴组织中，但关于NK细胞在血液和组织之间的再循环情况却知之甚少。这对于理解稳态下的再循环以及确定NK细胞在疫苗诱导的免疫和感染反应中的作用都具有重要意义。因此，利用假输入淋巴管插管模型，对牛在稳态条件下外周血、输入淋巴和淋巴结中的NK细胞百分比及其表型进行了研究。CD2 CD25 NK细胞是血液中NK细胞的主要亚群。相比之下，CD2 CD25 NK细胞是皮肤引流输入淋巴管和淋巴结中的主要亚群，这表明CD2 NK细胞是通过输入淋巴管迁移至淋巴结的主要NK细胞亚群。此外，输出淋巴中存在的NK细胞比例较低，且主要为CD2亚群，这表明在稳态条件下NK细胞可以从淋巴结中逸出并返回循环系统。这些分区数据表明，在稳态条件下NK细胞代表了一群再循环淋巴细胞，因此在疫苗接种或感染的免疫反应过程中可能具有重要作用。
