Western blot analysis with patient serum. (A) Western blot analysis of immune precipitates from BCMA-293 stable transfectants, BCMA-293 transient transfectants, empty vector-293, and nontransfected 293 cells. (B) Immune precipitates (IP) from BCMA-293 (ST) and vector-293 (VT) cell lysates were blotted with patient serum (1:200 dilution) obtained before BMT, before DLI, and 4 months after DLI.