Critical role of the N-terminal region of mEAR2 for its DC chemotactic effect. (A) Alignment of the amino terminal sequences of hEDN, mEAR2, human eosinophil cationic protein (hECP), human pancreatic ribonuclease (hPR), and human angiogenin (hANG). Regions of identical sequence shared by EDN and mEAR2 are identified within the open boxes and, if shared by ECP, hPR and hANG, the boxes are extended to include them. The additional amino-terminal residues of the “-4” form of EDN are included in parentheses. An arrow indicates the position of the universally conserved histidine that serves as a crucial catalytic residue in all RNase A superfamily ribonucleases. The RNases predominantly produced by eosinophils are shown in black. (B) The N-terminal sequence of chimeric hPR/mEAR2. (C) Chemotaxis of human Mo-iDCs in response to mEAR2 and hPR/mEAR2 chimera. Chemotaxis of iDCs is shown as the average cell migration (mean ± SD) of triplicate wells.