CSF2 and infection: OT-I cell proliferation was quantified by measuring CTV intensities by FACS, which showed that infection of GM-CSF-cultured BMDCs with heat-iMVA enhanced the capacity of BMDCs to stimulate the proliferation of OT-I T-cells at all tested OVA concentrations (0.1, 0.3, and 0.5 mg/ml), as indicated by CTV dilution in the dividing cells (Fig. 4a, b).