The skin is the body's main barrier against physical insults and microbial pathogens. Diverse and functionally specialized subsets of immune cells in the skin sense and respond to infection or various barrier breaches to activate an immune response and eventually, return to homeostasis. However, deregulated immune responses can also cause skin disorders, such as psoriasis.

This Nature Video introduces the environment and key participants in skin immunity during steady-state and disease.

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