For this purpose, expanded Vγ9Vδ2 T-cells were enriched from the PBMC cultures using negative MACS isolation and co-cultured with either EGFR+ SW480 colorectal cancer cells, PSMA+ 22Rv1 prostate cancer cells, or CD1d+ MM.1s multiple myeloma cells for an additional 24 hr; the TAA-Vδ2hi-lo bsVHH/bsVHH-Fc engagers were re-added to the respective conditions. The gene discussed is CD1D; the disease is plasma cell myeloma.