ACKR3 and myeloid sarcoma: During the course of our study, a close analog, ACT-1004-1239, was disclosed as an ACKR3 antagonist in the literature by Idorsia Pharmaceuticals26,27 and presented as a clinical candidate for the treatment of MS,28, 29, 30 making the present results relevant for the understanding of the potential therapeutic effect of ACKR3 modulation in MS.