IL1B and neoplasm: Based on pathway analysis of differentially expressed proteins, Ly6Ehi neutrophils support the activation and positive regulation of CD8+ T cells—through cytokines such as IL-12b, IL-1β, IL-6, and IL-10—while unstimulated GR1+ cells support an immunosuppressive tumor microenvironment through the recruitment of additional immunosuppressive myeloid cells (Figures 5D and 5E).