FOXP3 and neoplasm: Tumor implantation caused a dramatic increase in pulmonary CD4+CD25+Foxp3+ Tregs 21 days later, and this increase was unaffected by treatment with BEMPEG (3.1% ± 0.8, 3.1% ± 0.9 and 0.8% ± 0.1 of live cells for vehicle, BEMPEG and no tumor groups, respectively; Figure 2C,D).