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Immune signaling molecules are essential for activating neurons in the skin to cause chronic itching. Chronic itch can be caused by inflammatory conditions such as eczema and psoriasis. It is also associated with kidney failure, liver disease some cancers and nerve disorders.
Researchers showed that sensory neurons in mice and people are activated by the immune signaling molecule called interleukin-4 (IL-4)
Immune molecule stimulates nerve cells to cause itching, IL-4 signaling can jump-start chronic itching in the setting of inflammation but also independently of pathways directly linked to inflammation.
Chronic idiopathic pruritus, is not associated with inflammation, that is why anti-inflammatory treatments, such as steroid creams are ineffective.
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