Anti cd137 clone 3h3

C57BL/6 mice were purchased from The Jackson Laboratory (Bar Harbor, ME). OT-I RAG^−/− transgenic mice were bred in-house. All mice were maintained in the UConn Health animal facility in accordance with National Institutes of Health guidelines. Spleen plus lymph node preparations from CD45.1⁺ RAG^−/− OT-I transgenic mice containing 5 × 10⁵ CD8⁺ T cells were adoptively transferred i.v. into CD45.2⁺ C57BL/6 recipients that were subsequently injected i.p. with 50 μg SIINFEKL peptide (Life Technologies; Grand Island, NY) and 30 μg Rat IgG or 20 μg anti-CD134 (clone OX86, Bio X Cell, Lebanon, NH) plus 10 μg of anti-CD137 (clone 3H3, Bio X Cell) agonists the following day as previously described (19 (link)) (20 (link)).

When tumors became palpable (~ 60 mm³), mice were randomly divided into treatment groups. Mice were anesthetized prior to and during treatment using 2%–5% isoflurane. Tumors receiving PBNP-PTT were intratumorally injected with 2.5 mg/kg PBNPs. Following injection, tumors were irradiated with the NIR laser (808 nm; Laserglow Technologies, Toronto, ON, Canada) for 10 min, and temperatures were measured by thermal camera at one minute intervals (FLIR, Arlington, VA). Eyes were covered with opaque black cardboard during treatment to avoid eye damage by the laser. Mice receiving mAb treatments were intraperitoneally injected with 5, 10, or 15 mg/kg anti-CTLA-4 (clone 9D9), 15 mg/kg anti-PD-1 (clone RMP1–14), or 15 mg/kg anti-CD137 (clone 3H3) (all mAbs were purchased from BioXCell, West Lebanon, NH) every three days for two weeks (i.e., on days 1, 4, 7, 10, 13, 16, totaling 6 doses). After administering the individual treatments, the mice were monitored for tumor progression and survival.