9:00 AM - 9:10 AM
[O3-D-AM1-04] ILDR2, a new immune checkpoint molecule, is expressed on CD206-positive macrophages in sublingual mucosa.
Keywords:Sublingual Mucosa、CD206+ macrophages、Immune checkpoint molecule
Background: In the murine pollen allergy model, repeated allergen painting onto sublingual mucosa (SLM) induces CD206+ macrophages (Vaccine, 2014). The SLM macrophages suppress the function of dendritic cells (DCs) via IL-10 production, suggesting these cells have a tolerogenic activity to antigen-specific T-cell responses (Int Immunol, 2020).
Objectives: After repeated antigen painting, we investigate ILDR2 expression on SLM CD206+ macrophages.
Methods and Results: After isolating sublingual cells, we sorted and compared the gene expression profiles of three subpopulations of granulocyte-depleted SLM leukocytes (Fr-1: CD11bloCD11c+CD206-, Fr-2: CD11bhiCD11c-CD206-, Fr-3: CD11bintCD11c-CD206+) by microarray analyses. We found that Fr-3 preferentially expresses a gene encoding ILDR2, a B7-family immune checkpoint molecule related to T-cell suppression. We generated a rabbit monoclonal antibody (mAb) against mouse ILDR2 by immunizing a peptide from a part of the Ig-like domain. Using this mAb, we detected ILDR2 protein is expressed on CD206hi macrophages in SLM and increased by repeated antigen painting. We will report the suppressive function of CD206hiILDR2+ macrophages to DC by in vitro study and show the genetic features of these macrophages by RNA sequencing analyses.
Objectives: After repeated antigen painting, we investigate ILDR2 expression on SLM CD206+ macrophages.
Methods and Results: After isolating sublingual cells, we sorted and compared the gene expression profiles of three subpopulations of granulocyte-depleted SLM leukocytes (Fr-1: CD11bloCD11c+CD206-, Fr-2: CD11bhiCD11c-CD206-, Fr-3: CD11bintCD11c-CD206+) by microarray analyses. We found that Fr-3 preferentially expresses a gene encoding ILDR2, a B7-family immune checkpoint molecule related to T-cell suppression. We generated a rabbit monoclonal antibody (mAb) against mouse ILDR2 by immunizing a peptide from a part of the Ig-like domain. Using this mAb, we detected ILDR2 protein is expressed on CD206hi macrophages in SLM and increased by repeated antigen painting. We will report the suppressive function of CD206hiILDR2+ macrophages to DC by in vitro study and show the genetic features of these macrophages by RNA sequencing analyses.