FLT3LG and neoplasm: Using an optimized flow cytometric assay shown in S5 Fig and described in the supplementary materials and methods (S1 File), the T cell-dependent isotypes IgG1, IgG2a, IgG2b, and natural isotype IgM were measured in plasma of vaccinated (+control), untreated and treated (Flt3-L, RT, RT+Flt3-L) tumour-bearing mice.