The junctional adhesion molecule-like protein (JAML) is important for the inflammatory response during contact hypersensitivity

• Published in: Contact dermatitis Vol. 89; no. 5; pp. 323 - 334
• Main Authors: Mraz, Veronika, Lohmann, Rebecca K D, Menzel, Mandy, Hawkes, Alana, Vaher, Helen, Funch, Anders B, Jee, Mia H, Gadsbøll, Anne-Sofie Ø, Weber, Julie F, Yeung, Kelvin, Ødum, Niels, Woetmann, Anders, McKay, Dianne, Witherden, Deborah, Geisler, Carsten, Bonefeld, Charlotte M
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01.11.2023
• Subjects: Adenoviruses; Allergens; Animal models; Animals; CD4 antigen; CD8 antigen; CD8-Positive T-Lymphocytes; Cell activation; Contact dermatitis; CXCL10 protein; Dermatitis, Allergic Contact; Epidermis; Humans; Hypersensitivity; Inflammation; Junctional Adhesion Molecules; Keratinocytes; Ligands; Lymphocytes; Lymphocytes T; Mice; Mice, Inbred C57BL; Mice, Knockout; Wound healing; γ-Interferon; CXADR; epidermal-resident memory T cell; JAML; contact hypersensitivity
• ISSN: 0105-1873; 1600-0536
• DOI: 10.1111/cod.14409

The junctional adhesion molecule-like protein (JAML) plays important roles in wound healing and activation of epidermal γδ T cells in mice. Whether JAML plays a role in contact hypersensitivity (CHS), the animal model of allergic contact dermatitis (ACD), is not known. To examine the role of JAML in CHS, we used various mouse models of CHS in JAML knockout (KO) and wild-type (WT) mice. Furthermore, the expression of the JAML ligand coxsackievirus and adenovirus receptor (CXADR) on keratinocytes was accessed in vitro and in vivo. JAML KO mice had a diminished inflammatory response during both the sensitization and elicitation phase of CHS and had reduced numbers of CD8 and CD4 T cells in the epidermis. Furthermore, interferon γ (IFNγ), interleukin 1β (IL-1β) and CXCL10 production were significantly reduced in JAML KO mice during the elicitation phase. We found that CD8 T cells express JAML and that JAML is essential for rapid flare-up responses to contact allergens. Finally, we show that keratinocytes up-regulate the JAML ligand CXADR following exposure to contact allergens. Our study is the first to show a central role of JAML in CHS and reveals a potential new target for the treatment of ACD in humans.