Contact allergens induce CD8⁺ T cell‐derived interleukin 10 that appears dispensable for regulation of contact hypersensitivity

Abstract

Interleukin 10 (IL‐10) has been implied in the regulation of allergic contact dermatitis. Using transcriptional reporter mice we analyzed cellular sources of IL‐10 during contact hypersensitivity (CHS) and identified IL‐10 expressing CD8+ T cells in the skin that are antigen‐specific, display PD‐1, an effector memory phenotype, and IL‐10 expression comparable to that of CD4+ T cells. However, in mice with a selective IL‐10 deficiency in CD8+ T cells CHS responses were comparable to that of controls, even in the absence of CD4+ cells, suggesting that CD8+ T cell‐derived IL‐10 does not contribute significantly to the resolution of CHS responses.

Lack of Type 2 Innate Lymphoid Cells Promotes a Type I-Driven Enhanced Immune Response in Contact Hypersensitivity

“…We therefore addressed a potential role of IL-10-producing ILC2s in CHS by using IL-10 transcriptional reporter mice (IL10GFP, VERTX) in the CHS model. As demonstrated previously (Dolch et al., 2017), hapten challenge of sensitized mice induced prominent IL-10 expression in Lin + cells of the skin, which was almost exclusively restricted to different T-cell subsets. In contrast, no relevant IL-10 signal was detected in Lin – cells in the skin of CHS or naive mice (data not shown), suggesting that at least under the conditions used in this study IL10 production of ILC2s does not play a relevant role in regulating the immune response in CHS.…”

Recent advances in understanding and managing contact dermatitis

“…Interestingly, similar to observations in viral infections 51 , 52 , IL-10-producing CD8 + T cells can be detected in the late elicitation phase of CHS 53 . Although in respiratory syncytial virus lung infection an autocrine regulatory role of these effector cells has been shown 52 , in the CHS model this could not be confirmed.…”

Evaluation of the profile of inflammatory cytokines, through immunohistochemistry, in the skin of patients with allergic contact dermatitis to nickel in the acute and chronic phases

“…It shows a regulatory activity in the sensitization and elicitation phases of ACD, contributing for the control of the immune response to Ni2+. 14 , 39 , 40 Ni2+-specific Tregs cell clones from non-allergic individuals produce higher levels of IL-10 than those from allergic patients. 7 …”