The skin microbiome is an ecosystem comprised of a multitude of microbial species interacting with their surroundings, including other microbes and host epithelial and immune cells. These interactions are the basis of important roles within the skin microbiome that provide benefit to the host, boosting multiple aspects of barrier function, a critical function of this essential organ. However, with reward always comes risk; resident skin microbes function in a context-dependent manner, set on the backdrop of a dynamic host and microbial milieu. Here, we discuss the reward of hosting a microbial ecosystem on the skin, including protection from pathogens and tuning of the skin microenvironment. We also give consideration to how these skin residents, often termed “commensals” can cause disorder, damage, and promote skin disease.

皮肤微生物组是一个生态系统，由众多与其周围环境相互作用的微生物物种组成，包括其他微生物和宿主上皮细胞和免疫细胞。这些相互作用是皮肤微生物组中重要角色的基础，为宿主提供益处，增强屏障功能的多个方面，这是这一重要器官的关键功能。然而，回报总是伴随着风险；常驻皮肤微生物以动态宿主和微生物环境为背景，以依赖环境的方式发挥作用。在这里，我们讨论在皮肤上建立微生物生态系统的回报，包括保护免受病原体侵害和调整皮肤微环境。我们还考虑了这些皮肤居民（通常被称为“共生者”）如何导致疾病、损害和促进皮肤病。