Immunotoxins targeting BCMA and albumin-binding fusion protein. (A) Schematics of various anti-BCMA immunotoxin constructs of Fab-RIT (LMB70), scFv RITs (LMB-232 and LMB-234), and dsFv RITs (LMB-75, LMB-162, LMB-173, LMB-224, LMB-235, and LMB-237). LMB-162 contains an ABD from Streptococcus, LMB-173 contains a single domain anti-albumin antibody from Llama, LMB-224 is similar to LMB-162 but has a 17 amino acids linker on either side of ABD, LMB-235 has the ABD attached to the amino-terminus of VH, and LMB-237 has the ABD attached to the amino terminous of VL. Fur: Furin cleavage site. (B) Non-reducing SDS-PAGE gel with various RIT proteins. (C) Reducing SDS-PAGE gel with various RIT proteins.