Fig. 6

Distribution and toxicity analysis of M1-21 in wild-type mice. A ICG-labeled M1-21 (ICG-M1-21) (30 mg/kg) was tail-vein injected into wild-type ICR/JCL mice (female, 6 weeks old). Imaging animals at different post-treatment time points (0.5, 0.8, 1.15, 2, 5, 15, 24 h) was performed with the IVIS Lumina XR machine under 785 nm excitation light. B WT ICR/JCL mice (female, 6 weeks old) were intraperitoneally injected with PBS (Control) or M1-21 (30 mg/kg) every two days. One week later, the animals’ different organs were harvested and subjected to tissue sectioning and H&E staining. Photos were taken by inverted microscope (400×, Nikon TE2000). C Acute toxicity of M1-21 was measured by a single intraperitoneal injection of M1-21 (100 mg/kg, 150 mg/kg, or 200 mg/kg) in ICR/JCL mice (female, 6 weeks old, n = 3 for each group). The mice’s diet and activity were observed continuously for 14 days. D M1-21 hemolysis was measured by incubating mouse blood with M1-21 at different concentrations (25, 50, 100, 200, 400, 800 µg/mL). Water and PBS were used as hemolysis positive and negative controls, respectively. The absorbance of the samples was measured at 540 nm and used to calculate the Hemolysis rate % = [(OD Sample - OD Negative) / (OD Positive - OD Negative)] × 100%. E Immunogenicity analysis of M1-21. ICR/JCL mice (female, 6 weeks old) were injected intraperitoneally with M1-21 (30 mg/kg) once a week for 4 weeks. Blood samples were collected from mice at different time points (Week 2 to Week 8) and the absorption of anti-M1-21 antibody in serum (1:1000 dilution) was measured by ELISA. HRP-conjugated anti-mouse IgG was used as an ELISA secondary antibody. Absorption was measured at 492 nm