Journal: Frontiers in Immunology
Article Title: Bacterial polyphosphates induce CXCL4 and synergize with complement anaphylatoxin C5a in lung injury
doi: 10.3389/fimmu.2022.980733
Figure Lengend Snippet: Polyphosphates regulate CXCL4 through PI3K/Akt signaling in macrophages. (A) CXCL4 release from C57BL/6J wild type macrophages (PEMs) after incubation with long-chain or short-chain polyphosphates ± LPS (100 ng/ml), Ctrl: resting control cells, 24 h, ELISA. (B) CXCL4 mRNA expression in macrophages (PEMs) after polyphosphates ± LPS, 24 h, RT-PCR. (C) CXCL4 release from macrophages (BMDMs) of wild type (WT), MyD88 -/- and TRIF -/- mice, 24 h, ELISA. (D) Relative quantification of phosphorylated Akt (threonine-308) in macrophages (BMDMs) at 0-60 min after long-chain polyphosphates. The values of fluorescence intensities (FI) were normalized to controls (0 min), bead-based assay. (E) CXCL4 release from polyphosphate-stimulated macrophages (BMDMs) co-treated with the Akt inhibitor, Wortmannin, 24 h, ELISA. (F) CXCL4 release from macrophages (BMDMs) co-treated with the Akt inhibitor, Ly294002 (stock was dissolved in DMSO), 24 h, ELISA. (G) Contour plots of phospho-Akt in F4/80 + macrophages (BMDMs) after activation with short/long-chain polyphosphates and LPS, 60 min, flow cytometry. (H) Geometric mean fluorescence intensities (gMFI) of pooled data (n=4/condition) as in frame G. Data are presented as mean ± SEM; *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001; n.d.: not detectable.
Article Snippet: The following substances were slowly injected intratracheally (i.t.) in 40 μl phosphate buffered saline (PBS): Synthetic polyphosphates of the doses and chain-lengths as indicated in the figure legends, recombinant mouse C5a (500ng/mouse; R&D Systems, Minneapolis, MN, USA), and recombinant mouse CXCL4 (500ng/mouse; R&D Systems, Minneapolis, MN, USA).
Techniques: Incubation, Control, Enzyme-linked Immunosorbent Assay, Expressing, Reverse Transcription Polymerase Chain Reaction, Quantitative Proteomics, Fluorescence, Bead-based Assay, Activation Assay, Flow Cytometry