EWI-2/CD316 is an inducible receptor of HSPA8 on human dendritic cells. Mol Cell Biol

Novartis Institutes for Biomedical Research Vienna, A-1230 Vienna, Austria.
Molecular and Cellular Biology (Impact Factor: 4.78). 12/2007; 27(21):7718-26. DOI: 10.1128/MCB.00180-07
Source: PubMed


The activation of dendritic cells is marked by changes both on their cell surfaces and in their functions. We define EWI-2/CD316
as an early activation marker of dendritic cells upregulated by Toll-like receptor ligands clearly before CD86 and CD83. By
expression cloning, human heat shock protein A8 (HSPA8), a member of the hsp70 family, was identified as the ligand for EWI-2.
Soluble EWI-2 bound both to cells expressing HSPA8 and also to immobilized HSPA8 protein. Although heat shock proteins are
evolutionarily well conserved, other members of this class, including human hsp60 and mycobacterial hsp65, did not bind to
EWI-2. The ligation of EWI-2 enhanced the CCL21/SLC-dependent migration of activated mature dendritic cells but attenuated
their antigen-specific stimulatory capacities. Important functions of recently activated dendritic cells are thus critically
modulated by the newly discovered HSPA8-EWI-2 interaction.

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