The BAC RP23-80N19, comprising the entire Fpr-rs3 gene, in which the cassette IRES-Cre-IRES-GFP-frt-Zeo-Puro-Frt was inserted after Fpr-rs3 stop codon. The resistance cassette was removed by in vitro flippase-induced recombination, and the resulting vector was injected into the pronuclei of C57BL6/J-DBA/2J F2 zygotes. Two independent lines were analyzed in this work, labeled as #2 and #4.