Fig. 3.

Ab-retargeting reduces intratumor myeloid cells and supports NK cell and CD8 T-cell infiltration. a MC38-pSia cells were used to establish s.c. tumors in Ad5-vaccinated mice. Tumor-bearing mice received i.v. injections of DE1scFv-pSia or saline, and were sacrificed according to the shown schedule. Tumor tissue was examined for infiltration of different leukocyte subsets via flow cytometry. b Frequencies of NK cells (NK1.1⁺CD49b⁺) were calculated as percentage of CD45.2⁺ leukocytes. NK cell activation was determined by surface expression of CD107a. Macrophages (Gr1⁺F4/80^high) and different fractions of myeloid-derived suppressor cells (MDSCs; P1: CD11b⁺ Gr1^high; P2: CD11b⁺ Gr1^int) are shown in c and d, respectively. Group size was in general n = 5 with following exceptions: n = 7 (NK cells/day 10/DE1scFv-pSia); n = 6 (NK cells/day 17/control and DE1scFv-pSia groups); n = 4 (CD107a^high – NK cells/control). e Frequencies of CD4⁺ and CD8⁺ T cells were measured as percentage of CD90.2-positive lymphocytes, and individual ratios of CD8 to CD4 T cells were calculated. Group size: n = 5 (day 10) and n = 6 (day 17). f Splenocytes were prepared from sacrificed mice, incubated with the mutated MC38 peptide Adpgk-R304M (ASMTNMELM), or an irrelevant control peptide, and responding neoantigen-reactive CD8 T cells were identified by intracellular staining for IFNγ (group size: n = 8). Two-tailed unpaired t test was used to calculate statistics: *p ≤ 0.05; **p ≤ 0.01. Error bars refer to standard deviation (SD). Source data are provided as a source data file