Figure 3. Anti-B16F10 antibodies serum levels are elevated.

Mice of the indicated genotype were primed with 5×10⁶ irradiated B16F10 and challenged with 2.5×10⁵ live B16F10. A At time of sacrifice (when tumours reached 10 mm² or in the case of tumour-free mice after 50 days), serum was obtained. 1/500 diluted serum was used to stain B16F10. Secondary antibody was an anti-mouse pan Ig APC. B Serum was obtained before priming, 4 weeks after priming, or 16 days after live tumour challenge and used to stain B16F10. Naïve littermate controls or unprimed but challenged controls were included were indicated. Secondary antibodies used were anti-mouse IgM FITC (upper panel) or anti-mouse IgG FITC (lower panel). * p value by Mann-Whitney test comparing mean fluorescence of serum staining B16F10. These findings were reproduced three times with similar results with n>10 in each group.