2.3. Tumor Model (B16-OVA, Melanoma)

B16F0-OVA (expressing plasmid derived full length OVA) cells were obtained from Dr. Edith Lord (University of Rochester, Rochester, New York, NY, USA) and cultured as described previously [10,30]. Solid tumors were induced with s.c. injection of 1 × 10⁶ B16-OVA cells. From day five onwards, detectable solid tumor was measured using Digimatic Digital calipers (Mitutoyo 500-196, Aurora, IL, USA). Tumor size, expressed in mm², was obtained by multiplication of diametrically perpendicular measurements. Animals were monitored for long-term survival. However, in order to minimize pain and discomfort, mice were euthanized when tumors reached 300 mm².