Figure 1.

Ascites fluid from BR5-akt tumor-bearing mice contain high levels of myeloid-derived suppressor cells. (A) Schematic of experiment. Syngeneic FVB mice (n = 7) were implanted intraperitoneally with 1 × 10⁶ BR5-Akt tumor cells; 28 days after tumor implantation, cells were extracted from ascites fluid, passed over a 40 μM mesh (which eliminates virtually all malignant cells which exist as multi-cell spheroids), and analyzed by flow cytometry. (B) Prior to in-depth analysis, cells were gated on single, living, CD45⁺ cells. (C) The resulting immunological makeup of gated ascites cells was determined using non-curated tSNE analysis which resulted in the identification of 10 distinct clusters. (D) Identification and quantitation of clusters: B cells (B220+/I-Ab+CD11b-), CD8+ T cells (CD3+/CD8+), Macrophages (CD11b⁺/F4-80⁺/Ly6g⁻/Ly6c⁻), NK cells (CD3⁻/NK1.1⁺/NKp46⁺), pmnMDSCs (CD11b⁺/F4-80⁻/Ly6c⁺/Ly6g^hi), CD4⁺ Conventional T cells (CD3⁺/CD4⁺ CD25⁻), CD4⁺ regulatory T cells (CD3⁺/CD4⁺/CD25⁺), unknown cluster #1 (CD11b⁻/F4-80⁺/NKp44⁺/NKp46⁺/Ly6g⁺/CTLA4⁺), unknown cluster #2 (CD11b⁺/F4-80⁺/Ly6c⁺/I-Ab⁺/CD80⁺/NKp44⁺), unknown cluster #3 (CD11b⁺, F4-80⁻, Ly6c⁻, Ly6g⁻, I-Ab⁻).