Lipoxin A4 (LXA4; 5S, 6R, 15S-trihydroxy-7E, 9E, 11Z, 13E-eicosatetraenoic acid) and lipoxin B4 (LXB4; 5S, 14R, 15S-trihydroxy-6E, 8Z, 10E, 12E-eicosatetraenoic acid) were the first lipid SPMs to be discovered (Chiang and Serhan 2017). They are produced from the