Vaccines are applied to large populations, but only recently has research into immunologic responses and mechanisms started to increase exponentially. Some live vaccines, such as the tuberculosis vaccine bacillus Calmette-Guérin, protect against other infections nonspecifically by eliciting complex immune responses which are not specific antibody related. These heterologous effects are explained by the concept of trained immunity. This editorial introduces five narrative reviews offering recent insights on innate and adaptive immune memory towards a variety of pathogens.

中文翻译：

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疫苗接种和免疫训练的异源作用

疫苗适用于大量人群，但直到最近才对免疫反应和机制进行研究，呈指数级增长。一些活疫苗，例如结核病疫苗卡介苗（Calmette-Guérin），会引起与特定抗体无关的复杂免疫反应，从而非特异性地预防其他感染。这些异源作用是通过训练后的免疫力的概念来解释的。这篇社论介绍了五篇叙述性评论，它们提供了对多种病原体的先天性和适应性免疫记忆的最新见解。