The original antibody 15B2 was generated by immunizing six week old female Ablexis transgenic mice with both rHu BCMA-Fc and cynomolgus BCMA-Fc or adherent 293 cells (Ad293) expressing either Hu BCMA or Cyno BCMA. The original mouse antibody 15B2 was mutated to a germline form using primers designed to mutate four non-germline residues in 15B2, which resulted in the generation of this lead optimized antibody.