on June 17, 2006
Simona Infantino and Marcus Thelen
The orphan receptor RDC1 may function as a chemokine receptor. We have characterized its expression pattern in leukocytes, in particular on B cells.
So far, we have tested most of the known human chemokines as potential ligands, but could not identify a specific agonist.
Receptor internalization on primary and transfected cells was measured as agonist induced response. Recent results obtained in collaboration with our partners in Paris suggest that CXCL12 binds RDC1 and induces its internalization in T cells. However, results form our laboratory indicate that primary B cells do not respond to CXCL12, but to a yet unknown agonist. We assume that the physiological relevant ligand could be an unknown molecule. To this end supernatants derived from different cell culture systems, mimicking the environment where RDC1 positive cells reside, are tested for potential activity on RDC1 and will be fractionated using standard biochemical techniques. Once a ligand has been identified we will study its expression patter and physiological significance.