Figure 6.

Local HCA-EFZP-IL-12 administration results in T cell infiltration in the osteosarcoma microenvironment

(A) Scheme of the experimental schedule. K7M2 murine osteosarcoma cells (5 × 10⁵ per tibia) were injected into the tibial tuberosity of BALB/c mice (day −10). Animals were treated twice intratumorally with either a saline solution (control group) or 2 × 10⁸ IU of HCA-EFZP-IL-12 (days −5 and −7). 3 days later, both groups were administered mifepristone intraperitoneally for 2 weeks with increasing doses (1 mg/kg on days 0–4, 4 mg/kg on days 7–9, and 8 mg/kg on days 10 and 11). Animals were sacrificed at day 25 after first mifepristone induction. (B and C) Flow cytometry of T cell populations in tumor-infiltrating lymphocytes (TILs) in tibia (B) or lung (C) of mice bearing K7M2 intratibial tumors at 25 days after IL-12 induction. Bars indicate mean ± SD (N = 4–5). Mann-Whitney test.