CD1a and Lipids as Mediators of T Cell Activation in the Skin

  • J Invest Dermatol. 2025 Oct;145(10):2428-2435. doi: 10.1016/j.jid.2025.03.020.
Lauren M Fahmy  1 Oluwaseyi O Adeuyan  1 Annemieke de Jong  2
Affiliations
  • 1. Department of Dermatology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, New York, USA.
  • 2. Department of Dermatology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, New York, USA. Electronic address: [email protected].
Abstract

Despite increasing insights in cytokine pathways involved in T cell-mediated inflammatory skin diseases, the upstream T cell triggering events through antigen-presenting molecules and antigens often remain incompletely understood. Recent studies have proposed an immunopathogenic role for T cells that are activated through CD1a, a lipid antigen-presenting molecule abundantly expressed on antigen-presenting cells in human skin. These CD1a-restricted T cells are thought to play a role in psoriasis, atopic dermatitis, and allergic contact dermatitis. In this review, we discuss modes of T cell activation by CD1a proteins and lipid antigens and bacteria as well as recent insights in local and systemic functions of CD1a-restricted T cells in inflammatory skin disease.

Keywords
CD1a; Inflammatory skin diseases; Langerhans cells; Lipid antigens; T cells.