CEACAM5 and colon carcinoma: To assess the in vivo effect of αCEA/αCD3 diabody secreted by MSCdAb on tumor growth, we established xenografts of the CEA-positive human colon carcinoma cell line HCT-116, previously transduced with the LentiLuc (HCT-116Luc), through s.c. inoculation of 106 cells in the dorsal region of nude mice.