Bacterial artificial chromosome (BAC) library (CHORI) was used to obtain a 120 kb BAC (RP24-147I16) containing the entire mouse Cx3cl1 (chemokine (C-X3-C motif) ligand 1) gene. This BAC was modified to replace exon 1 of Cx3cl1 with an mCherry fluorescent protein. CCL22 and CCL17 sequences were removed from the BAC by restriction digest. (J:178874)