Functions of mucosal associated invariant T cells in eye diseases

Abstract

Mucosal-associated invariant T (MAIT) cells are a unique subset of T cells that recognizes metabolites derived from the vitamin B2 biosynthetic pathway. Since the identification of cognate antigens for MAIT cells, knowledge of the functions of MAIT cells in cancer, autoimmunity, and infectious diseases has been rapidly expanding. Recently, MAIT cells have been found to contribute to visual protection against autoimmunity in the eye. The protective functions of MAIT cells are induced by T-cell receptor (TCR)-mediated activation. However, the underlying mechanisms remain unclear. Thus, this mini-review aims to discuss our findings and the complexity of MAIT cell-mediated immune regulation in the eye.

Keywords: T cells; autoimmune disease; eye; immunotherapy; metabolite.

Figure 1

MAIT cell functions in eye diseases. This figure shows how MAIT cells or TRAV1-2⁺ cells are involved in ocular diseases such as experimental autoimmune uveitis (EAU), age-related macular degeneration (AMD), acute anterior uveitis (AAU), and allergic conjunctivitis in different locations.

Figure 2

Pathological tissue images of autoimmune uveitis and Age-related Macular Degeneration (AMD). (A) Fluorescein Angiography (FA) (left) and Optical Coherence Tomography (OCT) (right) images of Vogt-Koyanagi-Harada (VKH) disease. FA shows multiple fluorescent leaks around the blood vessel. OCT shows retina layers with subretinal fluid, choroidal thickening, and retinal pigment detachment. (B) Indocyanine Green Angiography (left) and OCT (right) images of AMD. Images shows layers of retina with choroidal neovascularization associated with macular edema due to exudative changes.