Journal: Nature Communications
Article Title: Identification of a subset of immunosuppressive P2RX1-negative neutrophils in pancreatic cancer liver metastasis
doi: 10.1038/s41467-020-20447-y
Figure Lengend Snippet: a Single cell suspension was obtained from mouse spleen and expression of P2RX1 was determined in indicated immune cell types ( n = 3 per group, two independent experiments). Left dotted line indicates the mean of negative control (NC) (secondary antibody only), and right dotted line indicates the mean of Ly6G+ cells. b KPC cells were intrasplenically injected to seed livers of WT mice. A single cell suspension was obtained from liver metastases and adjacent liver tissues of WT mice at day 17. The frequency of CD45+P2RX1+ cells was determined by flow cytometry ( n = 4 per group, three independent experiments). c KPC cells were intrasplenically injected to seed livers of WT mice. Immune cells were enriched from single cell suspension of liver metastases and adjacent liver tissues at day 17. P2RX1 expression in the indicated immune cell types was determined by flow cytometry ( n = 4 per group, three independent experiments). d Representative images of H&E staining and immunofluorescence staining of P2RX1 (Green), Ly6G (Red) and DAPI (Blue) in KPC mice spontaneous liver metastases (representative results from six independent experiments). 50 μm scale bar for low power fields and 20 μm scale bar for high power fields. e , f H&E staining and immunofluorescence staining of P2RX1 (green), CD66b (red) and DAPI (blue) in a total of 20 clinical PDAC liver metastasis samples were performed. Representative images are shown in ( e ), and the percentages of P2RX1-CD66b+ cells are shown in ( f ). 50 μm scale bar for low power fields and 20 μm scale bar for high power fields. g , h KPC cells were intrasplenically injected to seed livers of BM chimeras: WT → WT, P2rx1 −/− → P2rx1 −/− , WT → P2rx1 −/− , and P2rx1 −/− → WT. Neutrophils were depleted in WT → P2rx1 −/− and P2rx1 −/− → WT mice by intraperitoneal injection of anti-Ly6G (clone 1A8) antibody. At day 17, liver metastases were analyzed by in vivo imaging ( g , n = 5 for WT → WT, P2rx1 −/− → P2rx1 −/− and WT → P2rx1 −/− groups, n = 4 for WT → P2rx1 −/− + anti-Ly6G, P2rx1 −/− → WT and P2rx1 −/− → WT + anti-Ly6G groups, two independent experiments), and representative images of liver metastatic samples were shown ( h ). Bars represent mean ± standard deviation in ( f , g ). P values are derived from two-sided Student’s t test ( c , f ), or one-way ANOVA and Tukey’s multiple comparisons test ( g ). Source data are provided as a Source data file.
Article Snippet: For P2RX1 labeling (Alomone, 1:80), primary antibody was labeled for 30 min. After washing, fluorophore-conjugated secondary antibodies were labeled for another 30 min. Before sorting, SYTOX Blue (Thermo Fisher) was added to exclude dead cells.
Techniques: Expressing, Negative Control, Injection, Flow Cytometry, Staining, Immunofluorescence, In Vivo Imaging, Standard Deviation, Derivative Assay