CD19 and neoplasm: Although showing distinct tumor development kinetics and 4T1-induced tumors promoting splenomegaly and early elevation of the area in tDLNs, CD19 + IgD + high was the predominant subpopulation (CD19 + IgD +) in both spleen and tDLNs of control and 4T1 and E0771 tumor-bearing mice (Fig. 2a,b).