Unique Cell Subpopulations and Disease Progression Markers in Canines with Atopic Dermatitis.

Atopic dermatitis (AD) is a common pruritic inflammatory skin disease with unclear molecular and cellular contributions behind the complex etiology. To unravel these differences between healthy control and AD skin we employed single-cell transcriptomics, utilizing the canine AD model for its resemblance to human clinical and molecular phenotypes. In this study, we show that there are overall increases in keratinocytes and T cells and decreases in fibroblast populations in AD dogs. Within immune cell types, we identified an enriched γδ T cell population in AD, which may contribute to cutaneous inflammation. A prominent IL26-positive fibroblast subpopulation in AD was detected, which may activate neighboring cells in the dermal-epidermal niche. Lastly, by comparing dogs with different disease severities, we found genes that follow disease progression and may serve as potential biomarkers. In this study, we characterized key AD cell types and cellular processes that can be further leveraged in diagnosis and treatment.

Immunoglobulin-like receptors in chickens: identification, functional characterization, and renaming to cluster homolog of immunoglobulin-like receptors.

The cluster homolog of immunoglobulin-like receptors (CHIRs), previously known as the "chicken homolog of immunogloublin-like receptors," represents is a large group of transmembrane glycoproteins that direct the immune response. However, the full repertoire of putatively activating, inhibitory, or dual function CHIRA, CHIRB, and CHIRAB on chickens' immune responses is poorly understood. Herein, the study objective was to determine the genes encoding CHIR proteins and predict their function by searching canonical protein structure. A bioinformatics pipeline based on previous work was employed to search for the CHIRs from the newly updated broiler and layer genomes. The categorization into CHIRA, CHIRB, and CHIRAB types was assigned through motif searches, multiple sequence alignment, and phylogeny. In total, 150 protein-encoding genes on Chromosome 31 were identified as CHIRs. Gene members of each functional group (CHIRA, CHIRB, CHIRAB) were classified in accordance with previously recognized proteins. The genes were renamed to "cluster homolog of immunoglobulin-like receptors" (CHIRs) to allow for the naming of orthologous genes in other avian species. Additionally, expression analysis of the classified CHIRs across various reinforces their importance as immune regulators and activation in inflammatory tissues. Furthermore, over 1,000 diverse and rare CHIRs variants associated with differential Marek's disease response (P < 0.05) emphasize the impact of CHIRs on shaping avian immune responses in diverse contexts. The practical applications of these findings encompass advancing immunology, improving poultry health management, optimizing breeding programs for disease resistance, and enhancing overall animal health through a deeper understanding of the roles and functions of CHIRA, CHIRB, and CHIRAB types in avian immune responses.