Sublingual macrophage-associated ILDR2 contributes to immune tolerance via Treg induction.

The sublingual mucosa (SLM) has been used for sublingual immunotherapy (SLIT) which has the potential to induce antigen-specific immune tolerance. We previously demonstrated the CD206 macrophages that were increased in the SLM after repeated antigen exposure. These macrophages showed high expression of the gene encoding ILDR2 (Ig-like domain-containing receptor 2), an immune checkpoint molecule.

VSIG4/CRIg directly regulates early CD8 T cell activation through its counter-receptor in a narrow window.

T-cell responses are fine-tuned by positive and negative co-signal molecules expressed on immune cells and adjacent tissues. VSIG4 is a newly identified member of the B7 family of ligands, which negatively regulates innate inflammatory and CD4 T cell-mediated responses. However, little is known about the direct effects of VSIG4, which are exerted through an unidentified counter-receptor on CD8 T cells.