The impact of vaccines on heterologous adaptive immunity

摘要

Background: Vaccines induce antigen-specific memory in adaptive immune cells that enables long-lived protection against the target pathogen. In addition to this, several vaccines have beneficial effects greater than protection against their target pathogen. These non- specific effects are proposed to be the result of vaccine-induced immunomodulation. In the case of bacille Calmette-Guerin (BCG) vaccine, this involves induction of innate immune memory, termed 'trained immunity', in monocytes and natural killer cells.