Journal: Cell Reports Medicine
Article Title: DF6215, an α-optimized IL-2-Fc fusion, expands immune effectors and drives robust preclinical anti-tumor activity
doi: 10.1016/j.xcrm.2025.102518
Figure Lengend Snippet: DF6215 mediates robust lymphocyte expansion and modulates the tumor microenvironment, resulting in potent anti-tumor activity (A) Kinetics of Ki-67 + immune subset counts in the blood after human (h)IgG1 isotype control or DF6215 administration (0.23 mg/kg in light blue and 1.35 mg/kg in dark blue) in naive BALB/c mice ( n = 3/group). Data represent the mean ± SEM. (B) Efficacy of DF6215 in the mouse CT26 tumor model. Individual tumor volumes, per caliper measurements, are shown with treatment days and frequencies as indicated (vertical dotted lines, QW schedule). The number of complete responders (CRs) in each DF6215 treatment group is noted within each image. n = 10/group. Kaplan-Meier survival curves are shown, with the median survival indicated in brackets (log rank Mantel-Cox test: ∗∗∗ p < 0.001 and ∗∗∗∗ p < 0.0001). Top: mice were enrolled into treatment groups on day 11, when tumors averaged 218 mm 3 in size, and once weekly treatment began. Bottom: mice were enrolled into treatment groups on day 12, when tumors averaged 181 mm 3 in size, and once weekly treatment began. See also . (C and D) BALB/c mice ( n = 10/group) were engrafted with CT26 and treated i.p. with a single dose of DF6215 (0.675 mg/kg) or hIgG1 isotype after mice were enrolled into treatment groups when tumors averaged ∼218 mm 3 in size. (C) (Left) Absolute cell count quantification of indicated immune subsets in the tumor microenvironment 7 days post-treatment. Data shown are the mean ± SEM. (Right) Immune subset counts in tumors 96 h post-treatment. Significance for DF6215 relative to isotype by unpaired t test was noted as ∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001, ∗∗∗∗ p < 0.0001, and ns, not significant. (D) Cytokines in blood as assessed by a Luminex proinflammatory panel 24 h post-treatment. Significance for DF6215 relative to isotype by one-way ANOVA with Tukey’s test is noted as ∗∗∗ p < 0.001, ∗∗∗∗ p < 0.0001, and ns, not significant.
Article Snippet: The mouse melanoma cell line B16F10 and colon carcinoma cell line CT26 were obtained from ATCC.
Techniques: Activity Assay, Control, Cell Characterization, Luminex