Fig. 5: Tumor‑derived G‑CSF induces persistent functional changes in neutrophil progenitors in vitro.

a Experimental design. Bone marrow progenitors (CD3e⁻CD45R⁻NK1.1⁻CD11b⁻Ly6G⁻Ter119⁻) were isolated by immunomagnetic negative selection (modified from ref. ¹⁶). Cells were cultured with MOPC‑ or ^GMOPC‑conditioned medium for 6 days (a, left), or for 3 days followed by 3 days in control medium without stimulation (a, right). On day 6, the phenotype and function of newly differentiated Ly6G⁺ neutrophils (gating strategy Fig. S3a) were assessed. b–h Bone marrow progenitors cultured with MOPC‑ or ^GMOPC‑conditioned medium for 6 days were analyzed for morphology, phenotype, and function. b Representative Giemsa‑stained cytospins (scale bar = 20 µm). c ^GMOPC‑conditioned medium induced elevated differentiation of progenitors from n = 4 mice into Ly6G⁺ neutrophils in comparison to MOPC or –condensed medium or control medium. d ^GMOPC‑conditioned medium enhanced degranulation of Ly6G+ matured from progenitors isolated from n = 6 mice, in comparison to MOPC or –condensed medium. e ^GMOPC‑conditioned medium increased the proportion of CD62L^low Ly6G⁺ neutrophils maturated from progenitors isolated from n = 6 mice, in comparison to MOPC or –condensed medium. f ^GMOPC‑conditioned medium reduced CD11b expression on Ly6G⁺ neutrophils maturated from progenitors isolated from n = 6 mice, in comparison to MOPC or –condensed medium. g ^GMOPC‑conditioned medium elevated unstimulated ROS production of Ly6G⁺ neutrophils maturated from progenitors isolated from n = 6 mice, in comparison to MOPC–condensed medium. h ^GMOPC‑conditioned medium decreased phagocytosis of Ly6G⁺ neutrophils maturated from progenitors isolated from n = 4 mice, in comparison to MOPC–condensed medium. i–m Bone marrow progenitors were exposed to MOPC‑ or ^GMOPC‑conditioned medium for 3 days, followed by 3 days in control medium; newly differentiated Ly6G⁺ neutrophils were analyzed. i Initial ^GMOPC‑conditioned medium exposure increased degranulation of Ly6G+ neutrophils maturated from progenitors isolated from n = 6 mice, in comparison to MOPC–condensed medium. j Initial ^GMOPC‑conditioned medium exposure increased apoptosis of Ly6G+ neutrophils maturated from progenitors isolated from n = 6 mice, in comparison to MOPC–condensed medium. k Initial ^GMOPC‑conditioned medium exposure reduced CD11b expression on Ly6G+ neutrophils maturated from progenitors isolated from n = 6 mice, in comparison to MOPC–condensed medium. l Initial ^GMOPC‑conditioned medium exposure elevated unstimulated ROS production by Ly6G+ neutrophils maturated from progenitors isolated from n = 6 mice, in comparison to MOPC–condensed medium m Initial ^GMOPC‑conditioned medium exposure reduced phagocytosis of Ly6G+ neutrophils maturated from progenitors isolated from n = 6 mice, in comparison to MOPC–condensed medium. Co control (baseline) progenitor culture, MOPC cells incubated with MOPC‑conditioned medium, ^GMOPC cells incubated with ^GMOPC‑conditioned medium, SSC side scatter, ROS reactive oxygen species. Data are presented as means with individual values shown. Statistical tests: Kruskal–Wallis for multiple‑group comparisons with Bonferroni correction; two-sided Mann–Whitney for two‑group comparisons. *p  <  0.05, **p < 0.01, ***p < 0.001; #p < 0.1. Source data and exact p-values are provided as a Source Data file.