PDCD1 and neoplasm: Further analysis of these tumor-bearing mice revealed that TFR cells (PD1+Bcl6+Foxp3+CD4+CD3+), TFH cells (PD1+Bcl6+Foxp3−CD4+CD3+) and GC B-cells (GL7+Fas+CD19+) were more enriched in Foxp3+ Treg, CD4+Foxp3− effector T-cells (Teff) and B-cell compartment, respectively, in the tumor than those in the spleen (Fig. 1c and Additional file 3a,b).