Choreño Parra José Alberto, Martínez Zúñiga Nayeli, Jiménez Zamudio Luis Antonio, Jiménez Álvarez Luis Armando, Salinas Lara Citlaltepetl, Zúñiga Joaquín
Laboratory of Clinical Immunology I, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico.
Laboratory of Immunobiology and Genetics, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas, Mexico City, Mexico.
Front Immunol. 2017 Aug 14;8:967. doi: 10.3389/fimmu.2017.00967. eCollection 2017.
Natural killer (NK) cells are lymphocytes of the innate immune system, which play an important role in the initial defense against a wide variety of pathogens, including viruses and intracellular bacteria. NK cells produce cytokines that enhance immune responses directed toward pathogens and also exert cytotoxic activity against infected cells, thereby eliminating the reservoir of infection. Their role in defense against () has been recently studied, and there is increasing evidence that highlight the importance of NK cell function during pulmonary tuberculosis (PTB), especially in the absence of optimal T-cell responses. Additionally, in the last years, it has been observed that NK cells mediate secondary responses against antigens to which they were previously exposed, an ability classically attributed to lymphocytes of the adaptive branch of immunity. This phenomenon, called "innate memory," could have important implications in the efforts to develop therapies and vaccines to improve the initial phases of immune reactions against different microorganisms, especially those to which there is not yet available vaccines to prevent infection, as is the case for tuberculosis. Therefore, the possibility of inducing memory-like NK cells ready to act prior to contact with or during the earliest stages of infection becomes quite interesting. However, our understanding of the mechanisms of innate memory remains incomplete. Here, we review recent literature about the mechanisms involved in the formation and maintenance of NK cell memory and the role of these cells in the immune response during tuberculosis. Finally, we discuss if the current evidence is sufficient to substantiate that NK cells exert more rapid and robust secondary responses after consecutive encounters with .
自然杀伤（NK）细胞是先天性免疫系统的淋巴细胞，在针对多种病原体（包括病毒和细胞内细菌）的初始防御中发挥重要作用。NK细胞产生细胞因子，增强针对病原体的免疫反应，并对受感染细胞发挥细胞毒性作用，从而消除感染源。最近人们研究了它们在抵御（）方面的作用，越来越多的证据突显了NK细胞功能在肺结核（PTB）中的重要性，尤其是在缺乏最佳T细胞反应的情况下。此外，在过去几年中，人们观察到NK细胞介导针对其先前接触过的抗原的二次反应，这一能力传统上归因于适应性免疫分支的淋巴细胞。这种现象被称为“先天性记忆”，可能对开发治疗方法和疫苗以改善针对不同微生物的免疫反应初始阶段具有重要意义，尤其是对于尚无预防感染疫苗的微生物，如结核病。因此，诱导在接触（）之前或感染最早阶段就准备好发挥作用的记忆样NK细胞的可能性变得相当有趣。然而，我们对先天性记忆机制的理解仍然不完整。在这里，我们综述了关于NK细胞记忆形成和维持所涉及机制以及这些细胞在结核病免疫反应中作用的近期文献。最后，我们讨论目前的证据是否足以证实NK细胞在连续接触（）后会产生更快速、更强有力的二次反应。
