Distribution of MGL1 Binding Sites and MGL1/2-positive Cells in Lymph Nodes during the Sensitization Phase of Contact Hypersensitivity

Abstract

In the sensitization phase of delayed-type hypersensitivity, dermal macrophages (MOs) expressing MO galactose-type C-type lectin1 (MGL1) are known to migrate from the dermis to lymph nodes (LNs), and this migration was previously suggested to be an essential process in the establishment of the immune response to peripheral antigens. We hypothesize that the interactions between MGL1 and its ligands determine the localization of MGL1/2-positive cells within the LNs. In the present report, distribution of MGL1 binding sites was immunohistochemically examined by means of biotinylated recombinant MGL1 and compared with the distribution of MGL1/2-positive cells after epicutaneous sensitization of the mice with fluorescein isothiocyanate. The binding sites of MGL1 were mainly detected on the subcapsular sinus, interfollicular regions, and the T/B boundary. The distribution overlapped with the area where MGL1/2-positive cells that had migrated from dermis localized after sensitization with the antigen.