Clone 12A5 (See other available formats) Regulatory Status RUO Other Names Folate Receptor 4, FBP, FR δ Isotype Rat IgG1, κ Antigen Details Structure 28 kd protein consisting of 244 amino acids. Heavily glycosylated Distribution Expressed on mouse thymocytes and spleen cells. Highly expressed on natural regulatory (Treg) cells Function Mediate calcium-independent homophlic cell-cell adhesion Ligand/Receptor Folic acid and its derivative Cell Type Dendritic cells, T cells, Thymocytes, Tregs Biology Area Immunology, Innate Immunity Antigen References 1. Yamaguchi T et al 2007. Immunity 27:145 2. Spiegelstein O et al. 2000 Gene 258:117 Gene ID 64931 Folate receptor 4 (FR4) is a surface receptor for folic acid (Vitamin B9).It was recently reported that FR4 is highly and constitutively expressed on mouse CD4+ CD25+ natural regulatory T cells (Treg).The high expression of this surface marker on Treg can be used in combination with CD4 and CD25 to distinguish Treg from other types of T cells.Since FR4 is a surface marker,this antibody may be used in combination with anti-CD4 and/or CD25 to sort living T reg cells for functional studies.