Neutrophils migrate to sites of tissue damage, where they protect the host against pathogens. Often, the cost of these neutrophil defenses is collateral damage to healthy tissues. Thus, the immune system has evolved multiple mechanisms to regulate neutrophil migration. One of these mechanisms is reverse migration - the process whereby neutrophils leave the source of inflammation. In vivo, neutrophils arrive and depart the wound simultaneously - indicating that neutrophils dynamically integrate conflicting signals to engage in forward and reverse migration. This finding is seemingly at odds with the established chemoattractant hierarchy in vitro, which places wound-derived signals at the top. Here we will discuss recent work that has uncovered key players involved in retaining and dispersing neutrophils from wounds. These findings offer the opportunity to integrate established and emerging mechanisms into a holistic model for neutrophil migration in vivo.

中文翻译：

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中性粒细胞正向和反向迁移中的信号整合：基本原理和新兴机制。

中性粒细胞迁移到组织损伤部位，在那里它们保护宿主免受病原体的侵害。通常，这些中性粒细胞防御的代价是对健康组织的附带损害。因此，免疫系统已经进化出多种机制来调节中性粒细胞迁移。其中一种机制是反向迁移——中性粒细胞离开炎症源的过程。在体内，中性粒细胞同时到达和离开伤口——表明中性粒细胞动态整合相互冲突的信号以进行正向和反向迁移。这一发现似乎与体外已建立的化学引诱物层次结构不一致，后者将伤口衍生的信号置于顶部。在这里，我们将讨论最近的工作，这些工作揭示了参与从伤口中保留和分散中性粒细胞的关键参与者。