Utilizing a novel anti-BCMA ADC (HDP-101), Figueroa et al. determined that the level of antibody-bound molecules against BCMA per cell ranged from 1171–8987 in the multiple myeloma cell lines H929, INA-6, U266, MM.1S-Luc, RPMI-8226, MM.1S, LP-1, OPM-2, SKMM.1, and L363 [158]. Here, TNFRSF17 is linked to AL amyloidosis.