Af567

Four-week-old female nu/nu mice were approved for use by the Institutional Animal Care and Use Committee of the Third Military Medical University (Chongqing, China). Animal care was provided in accordance with the Guidelines for the Care and Use of Laboratory Animals. To establish xenografts, 3 × 10⁷ BON cells in 100 µL of PBS and 100 µL of Matrigel were intraperitoneally injected into nude mice. After the tumor size reached ~ 100 mm³, the animals were assigned randomly to 2 groups (control group, PBS; and treatment group, anti-NRP2 antibody), with 2 mice per group. The body weights of the mice were similar in each group on the assignment day. The treatment group received intraperitoneal injection of 50 µg anti-NRP2 antibody (R&D AF567) every other day 4 times (total amount, 200 µg); control mice received equivalent injections of PBS. Tumor sizes were observed every other day. The mice were sacrificed 7 weeks after BON cell injection, and the xenografts were harvested and placed in 10% formalin for section preparation. The xenograft volume was calculated as V_T = [ l (length) × w² (width)] × 0.52. Nude mice without tumors were excluded.