CD19 and lymphoma: Co-cultured with PBMCs, the ratio of proliferating cells in UCMSCs-Tandab(IL-6/CD20) treatment group decreased from 42.98% to 22.66%, while in rituximab group reduced from 49.52 to 31.54%, indicating that UCMSCs-Tandab(IL-6/CD20) were effective in inhibiting lymphoma cells, while PBMCs enhance the curative efficacy, which has been proved in the study of modified MSCs-Tandab(CD3/CD19) on B cell lymphoma [35].