Cytokine transcriptome profiling in acute experimental canine atopic dermatitis skin lesions after IL‐31 inhibition with lokivetmab

Abstract

AbstractBackgroundThe caninised monoclonal antibody lokivetmab (LKV), directed at interleukin (IL)‐31, is very effective at controlling pruritus in most dogs with atopic dermatitis (AD). However, evidence exists that IL‐31 is not required for the induction of acute allergic skin inflammation, which might explain why this treatment is less efficacious in some dogs with AD.Hypothesis/ObjectivesTo compare the comprehensive transcriptome analysis of house dust mite (HDM)‐sensitised dogs with and without treatment with LKV to attest our hypothesis that LKV does not majorly affect acute cytokine/chemokine production.AnimalsSix HDM‐sensitised atopic Maltese‐beagle dogs.Materials and MethodsIn this cross‐over study, the cytokine profiling of acute AD skin lesions was compared by RNA sequencing (RNA‐Seq), with or without LKV‐induced inhibition of IL‐31. Skin biopsies were obtained from each dog at 0, 6, 12, 24, 48, and 96 h after epicutaneous HDM allergen provocation.ResultsMacroscopic and microscopic skin lesion scores were not significantly different between the LKV‐ and nontreatment groups at any time points. Likewise, the results of RNA‐Seq analysis revealed no significant difference in the messenger (m)RNA expression of the major cytokines between these two groups. In LKV‐treated dogs, IL6, IL9, IL13, IL33, CCL17, and CCL22 were significantly upregulated compared to their baseline expression levels, suggesting that these cytokines are unaffected by IL‐31 inhibition.Conclusions and Clinical RelevanceIL‐31 inhibition is insufficient to prevent the expression of other proinflammatory mediators in acute AD and these could be considered as other potential therapeutic targets.