Furthermore, primary human MM cells from multiple myeloma patients were isolated and enriched by CD138 Microbeads, and flow cytometry results revealed that humanized nanobodies hu404-hfc, hu388-hFc and h32-hFc fusions showed strong binding ability with primary MM cells, and h32-hFc fusion showed better binding activity than hu404-hFc and hu388-hFc fusions (Fig. 2I). The gene discussed is SDC1; the disease is plasma cell myeloma.