Characterization and expression of DEC205 in the cDC1 and cDC2 subsets of porcine dendritic cells from spleen, tonsil, and submaxillary and mesenteric lymph nodes

Conventional dendritic cells (cDCs) are divided into the following different subtypes: cDC1, which promotes a Th1 response, and cDC2, which stimulates a Th2 and Th17 response. These cells have not been characterized in porcine lymphoid tissues. DEC205 is a receptor that increases antigen presentation and allows DCs to cross-present antigens. The objectives of this work were to characterize cDCs subsets in the tonsil, submaxillary and mesenteric lymph nodes and spleen lymphoid tissues and to determine their expression of DEC205 by flow cytometry. The cDC1 (MHCII^highCADM1^highCD172a^−/low) and cDC2 (MHCII^highCADM1^highCD172a⁺) phenotypes were confirmed by the expression of characteristic cDC1 and cDC2 transcripts (FLT3, XCR1 and FCER1α). Among all lymphoid tissues, the spleen had the highest frequency of total cDCs. The cDC1:cDC2 ratio showed that all lymph tissues had higher levels of cDC1 than levels of cDC2. DEC205⁺ cDCs were found in all analyzed tissues, albeit with different frequencies. Our research will facilitate the study on the function of these cells and the investigation of the strategies for DEC205 targeting and functional studies.