FCGR1A and Miyoshi myopathy: To assess the relationship between MM expansion and FcγRs modulation on HDNs, we assessed by flow-cytometry the CD64 and CD16 surface expression in healthy HDNs exposed for 24 hours to MM-conditioned media (obtained from two MM cell lines, U266 and OPM2) or IL-6, one of the most relevant cytokine in MM44.