The immune system and the nervous system are highly complex organs composed of various different cells that must interact with each other for proper function of the system. This communication can be mediated by soluble factors. The factors released by the nervous system (neurotransmitters) differ from those released by the immune system (cytokines). Nevertheless, the nervous and immune systems can influence each other’s activity because immune cells express neurotransmitter receptors, and neurons express cytokine receptors. Moreover, immune cells can synthesize and release neurotransmitters themselves, thus using neurotransmitter-mediated pathways via autocrine and paracrine mechanisms. Natural killer (NK) cells are innate lymphocytes that are important for early and effective immune reactions against infections and cancer. Many studies have shown the strong influence of stress and the nervous system on NK cell activity. This phenomenon may be one reason why chronic stress leads to a higher incidence of infections and cancer. Here, we review the effects of neuroendocrine factors on the different activities of NK cells. Understanding the effects of neuroendocrine factors on NK cell activities during physiological and pathophysiological conditions may result in novel therapeutic strategies to enhance NK cell functions against tumors.

免疫系统和神经系统是由各种不同细胞组成的高度复杂的器官，必须相互相互作用才能发挥系统的正常功能。这种交流可以通过可溶性因子来介导。神经系统释放的因子（神经递质）不同于免疫系统释放的因子（细胞因子）。尽管如此，神经和免疫系统仍会相互影响，因为免疫细胞表达神经递质受体，而神经元表达细胞因子受体。此外，免疫细胞自身可以合成和释放神经递质，因此可以通过自分泌和旁分泌机制使用神经递质介导的途径。自然杀伤（NK）细胞是先天淋巴细胞，对于抵抗感染和癌症的早期有效免疫反应非常重要。许多研究表明，压力和神经系统对NK细胞活性具有强烈影响。这种现象可能是慢性压力导致较高的感染和癌症发生率的原因之一。在这里，我们回顾了神经内分泌因子对NK细胞不同活性的影响。了解生理和病理生理条件下神经内分泌因子对NK细胞活性的影响可能会导致新的治疗策略，以增强NK细胞对抗肿瘤的功能。