Chronic urticaria and the pathogenic role of mast cells

The signs and symptoms of chronic urticaria (CU) are caused by the activation and degranulation of skin mast cells (MCs). Recent studies have added to our understanding of how and why skin MCs are involved and different in CU. Also, novel and relevant mechanisms of MC activation in CU have been identified and characterized. Finally, the use of MC-targeted and MC mediator-specific treatments has helped to better define the role of the skin environment, the contribution of specific MC mediators, and the relevance of MC crosstalk with other cells in the pathogenesis of CU. Here, we review these recent findings and their impact on our understanding of CU, with a focus on chronic spontaneous urticaria (CSU). Also, we highlight open questions, issues of controversy, and unmet needs, and we suggest what studies should be performed moving forward.

Automated summary

The signs and symptoms of chronic urticaria (CU) are caused by the activation and degranulation of skin mast cells (MCs). Recent studies have contributed to our understanding of the involvement and differences of skin MCs in CU. Moreover, novel mechanisms of MC activation in CU have been identified and characterized. The use of MC-targeted and MC mediator-specific treatments has also provided insights into the role of the skin environment and the relevance of MC crosstalk in CU pathogenesis. This review summarizes these recent findings and their impact on our understanding of CU, specifically focusing on chronic spontaneous urticaria (CSU). It also highlights unresolved questions, controversial issues, and future research directions.