THE RECEPTOR FOR ADVANCED GLYCATION END-PRODUCTS (RAGE) IS A CELLULAR-BINDING SITE FOR AMPHOTERIN - MEDIATION OF NEURITE OUTGROWTH AND COEXPRESSION OF RAGE AND AMPHOTERIN IN THE DEVELOPING NERVOUS-SYSTEM

The receptor for advanced glycation end products (RAGE), a newly-ident ified member of the immunoglobulin superfamily, mediates interactions of advanced glycation end product (AGE)-modified proteins with endothe lium and other cell types. Survey of normal tissues demonstrated RAGE expression in situations in which accumulation of AGEs would be unexpe cted, leading to the hypothesis that under physiologic circumstances, RAGE might mediate interaction with ligands distinct from AGEs. Sequen tial chromatography of bovine lung extract identified polypeptides wit h M(r) values of approximate to 12,000 (p12) and approximate to 23,000 (p23) which bound RAGE. NH2-terminal and internal protein sequence da ta for p23 matched that reported previously for amphoterin. Amphoterin purified from rat brain or recombinant rat amphoterin bound to purifi ed sRAGE in a saturable and dose-dependent manner, blocked by anti-RAG E IgG or a soluble form of RAGE (sRAGE). Cultured embryonic rat neuron s, which express RAGE, displayed dose-dependent binding of I-125-ampho terin which was prevented by blockade of RAGE using antibody to the re ceptor or excess soluble receptor (sRAGE). A functional correlate of R AGE-amphoterin interaction was inhibition by anti-RAGE F(ab')(2) and s RAGE of neurite formation by cortical neurons specifically on amphoter in-coated substrates. Consistent with a potential role for RAGE-amphot erin interaction in development, amphoterin and RAGE mRNA/antigen were co-localized in developing rat brain. These data indicate that RAGE h as physiologically relevant ligands distinct from AGEs which are likel y, via their interaction with the receptor, to participate in physiolo gic processes outside of the context of diabetes and accumulation of A GEs.