Fig. 12

a Schematic of the skin and muscle sensitization assay. The mice were subcutaneous and intramuscular injected with PBS (100 μL) or GPRPP-Y8U@P (1 mg/mL, 100 μL) once a day. After 3 days, the injection sites were for HE staining to evaluate sensitization. b The HE staining of muscle over the injection site. c The HE staining of skin over the injection site. R1, R2, and R3 represented repeat groups