BCMA and GPRC5D expression analysis in B-hBCMA/hGPRC5D MC38 cells by flow cytometry. Single cell suspensions from wild-type MC38 and B-hBCMA/hGPRC5D MC38 cultures were stained with species-specific anti-BCMA antibody (in house) and anti-GPRC5D antibody. Human BCMA and GPRC5D were detected on the surface of B-hBCMA/hGPRC5D MC38 cells. The 3-D03 clone of B-hBCMA/hGPRC5D MC38 cells was used for in vivo tumor growth assays.

Subcutaneous homograft tumor growth of B-hBCMA/hGPRC5D MC38 cells.B-hBCMA/hGPRC5D MC38 cells (5x10⁵; 1x10⁶; 5x10⁶) and wild-type MC38 cells (5x10⁵) were subcutaneously implanted into C57BL/6 mice (female, 8-10-week-old, n=6). Tumor volume and body weight were measured twice a week. (A) Average tumor volume ± SEM. (B) Body weight (Mean± SEM). Volume was expressed in mm³ using the formula: V=0.5 X long diameter X short diameter². As shown in panel A, B-hBCMA/hGPRC5D MC38 cells were able to form tumors in vivo and can be used for efficacy studies.