Skin-Infiltrating CD8+ T Cells Initiate Atopic Dermatitis Lesions

Abstract

Skin lesions in the allergic form of atopic dermatitis (AD) are induced by allergen-specific T cells that infiltrate the skin at the site of allergen exposure. Although Th2-type CD4+ T cells appear to be crucial in AD pathophysiology, little is known about the contribution of CD8+ T cells in the development of the allergic skin inflammation. In the present study, we have analyzed the respective role of CD8+ and CD4+ T cells in the development of AD skin lesions in a mouse model of allergen-induced AD. In sensitized mice, CD8+ T cells are rapidly and transiently recruited to the allergen-exposed site and initiate the inflammatory process leading to skin infiltration with eosinophils and Th1/Th2-producing cells. CD8+ T cell-depleted mice show no inflammation, demonstrating that these cells are mandatory for the development of AD. In contrast, CD4+ T cell-depleted mice develop a severe form of eczema. Furthermore, adoptive transfer of CD8+ T cells from sensitized mice into naive recipient mice leads to skin inflammation soon after allergen exposure. These data indicate that allergen-primed CD8+ T cells are required for the development of AD-like lesions in mice.

Dermatophagoides farinae extract induces severe atopic dermatitis in NC/Nga mice, which is effectively suppressed by the administration of tacrolimus ointment

“…When kept under specific pathogen-free (SPF) conditions, these mice remain normal and healthy. However, when placed in conventional surroundings, clinical signs including scratching behavior appear and IgE levels are elevated from the age of 8 weeks [22,23]. Thus, NC/Nga mice are often used as a sensitive animal model for human AD.…”

Mechanisms of IL-12 Synthesis by Human Dendritic Cells Treated with the Chemical Sensitizer NiSO4

“…Allergic contact dermatitis (ACD) caused by metallic ions and other reactive haptens is a T cell-mediated inflammatory skin disease (4)(5)(6). ACD is characterized by two phases: a sensitization phase and an elicitation phase.…”

Rosmarinic acid attenuates 2,4-dinitrofluorobenzene-induced atopic dermatitis in NC/Nga mice

“…7). Recently, it was shown that allergen-primed CD8 + T cells are required for the development of AD skin lesions in mice [38]. In the present study, RA significantly reduced skin lesion infiltration by CD8 + T cells, but in mouse and rat models, allergic inflammation was found to be dependent on CD4 + T cells, and CD8 + T cells were found to have a negative regulatory effect [39,40].…”