To determine whether BCMA–CST6–CAR-T–derived CST6 could suppress osteoclast differentiation, conditioned media (CM) from 24-hour cocultures of BCMA–CST6–CAR-T cells and MM cells at various ratios were collected and added to the culture media (50%) with RANKL and RAW 264.7 cells and cultured for 7 days (Figure 4A). This evidence concerns the gene CST6 and Miyoshi myopathy.