Fig. 4: Genetic deletion of Fgl2 from antigen-specific CD8⁺ rescues FcγRIIB⁺ CD8⁺ T cells in cancer and chronic viral infection.

a Schematic wherein Fgl2^−/− mice were given WT or Fgl2^−/− OT-I CD8⁺ T cells one day prior to cancer cell inoculation. Fourteen days later, animals were sacrificed for immune cell function to be measured via flow cytometry. b Representative flow plot of the isotype control for FcγRIIB staining on CD8⁺ T cells. c Representative flow plots of FcγRIIB staining, gated prior on Thy1.1⁺ congenic marked OT-I. d Frequency of FcγRIIB⁺ OT-I within WT or Fgl2^−/− OT-I subset normalized to WT OT-I (p = 0.0009) as well as e cell count of FcγRIIB⁺ OT-I (p = 0.020) in the draining lymph node of B16-challenged mice. Pooled data from three independent experiments, n = 14 in the WT OT-I group and 15 mice in the Fgl2^−/− OT-I group). f Schematic wherein Fgl2^−/− mice are given WT or Fgl2^−/− P14 one day prior to LCMV clone 13 infection. Mice were bled on days 4, 8, 12 and 15 and then sacrificed on day 15. g time course of cell number per ml (n = 6 mice per group) (p = 0.0043 and p = 0.0079 for the day 12 and day 15 comparisons respectively) h and frequency at day 8 of FcγRIIB⁺ CD45.1⁺ congenic marked WT or Fgl2^−/− P14 in the blood (n = 7 mice per group), p = 0.0111. Cell number of FcγRIIB⁺ P14 in the lymph nodes i, j spleen in Clone 13-infected mice is also shown (n = 5 mice per group), p = 0.0079 and p = 0.0079 respectively. k Schematic showing co-adoptive transfer wherein WT and Fgl2^−/− OT-I were transferred at a 1:1 ratio and mice were subsequently challenged with B16-OVA. l Representative flow plots gated first on Thy1.1⁺, then FcγRIIB⁺, and then Thy1.1⁺ vs Thy1.2⁺ and m summary data in the dLN of FcγRIIB⁺ WT (Thy1.1⁺) vs. Fgl2^-/− (Thy1.1⁺Thy1.2⁺) in tumor challenged mice, n = 5 mice per group, p = 0.0159. n Representative flow plot and o summary data showing frequency of Thy1.1⁺ caspase3/7⁺ of FcγRIIB⁻ WT vs. FcγRIIB⁻ Fgl2^−/− OT-I (n = 8 mice per group). p Representative flow plot and q summary data showing frequency of Thy1.1⁺ caspase3/7⁺ of FcγRIIB⁺ WT vs. FcγRIIB⁺ Fgl2^−/− OT-I, n = 8 mice per group, p = 0.0070. Pooled data from two independent experiments. Mann-Whitney non-parametric, unpaired two-sided tests were used. The error bar in summary figures denotes mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001. Source data are provided as a Source Data file. a, f, k is created with BioRender.com released under a Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International license.