Abstract: The skin is one of first lines of defense against external threats. Tissue-resident macrophages have pivotal functions in tissue-barrier integrity and homeostasis. Upon skin inflammation, a functional crosstalk between the sensory nervous system and tissue-resident immune cells can regulate cutaneous immune responses. However, depending on the pathological context, sensory neurons display pro- or anti-inflammatory regulatory properties. Here the inventors identify, in a model of ultraviolet (UV)-induced skin N damage, a regulatory role for type C low-threshold mechanoreceptor (C-LTMR) sensory neurons on the dynamic of dermal macrophage replacement by inflammatory monocytes through the neuropeptide TAFA4. Tafa4-KO mice present an unresolved fibrotic dermis after UV irradiation. Increased fibrotic score correlates with the upstream persistency of inflammatory monocytes and their MHC-II+ macrophage progeny.

Abstract: Products and methods for assessing the predisposition of a subject to develop an injury-induced chronic mechanical pain and/or an inflammatory-induced chronic thermal pain are provided. More specifically, methods for the assessment of the predisposition of a subject to develop an injury-induced chronic mechanical pain and/or an inflammatory-induced chronic thermal pain using the MYO1A gene as a biomarker and methods of treating selected subjects are provided.

Abstract: The present invention relates to the identification of Myo1a as a biomarker of conversion of acute pain into chronic pain, and as a therapeutic target. The invention in particular relates to products and methods for assessing the predisposition of a subject to develop an injury-induced chronic mechanical pain and/or an inflammatory-induced chronic thermal pain, and is particularly suited for mammals, preferably human subjects. The present invention more specifically relates to the assessment of the predisposition of a subject to develop an injury-induced chronic mechanical pain and/or an inflammatory-induced chronic thermal pain using preferably the MYO1A gene as a biomarker. Inventors herein provide binding reagents specific for MYO1A, compositions, devices, kits containing the same and animal model, and further describe their uses for assessing the predisposition of a subject to suffer from chronic pain.