Malat1 in 1

PMN-MDSCs were isolated as described in the cell isolation section, and mice received 1×10⁶ PMN-MDSCs by intravenous (i.v.) injection immediately after CLP. Control mice were treated with equal volumes of PBS. We used Malat1-IN-1 (MedChemexpress, New Jersey, NJ, USA) to regulate the downstream genes of Malat1. And we used Stattic (Selleck Chemicals, Houston, TX, USA) to inhibit the phosphorylation of STAT3 on Tyr705. In cell differentiation experiments, 5 μM Stattic or an equal concentration of Vehicle (DMSO) was added to the medium for 48 h. In the studies of cell function, 5 μM Stattic or an equal concentration of Vehicle was added to the medium for 6 h, followed by the T cell suppression assay. In animal experiments, 5 mg·kg^-1 Stattic or an equal concentration of Vehicle was intraperitoneally injected once before CLP and once two days after CLP.

The primary antibodies for NCAPD3 and PCLAF were obtained from Santa Cruz Biotechnology (CA, USA). Other primary antibodies for STAT3, AR, MYC, EZH2, AGO2, Ki67, β-actin and the secondary antibodies, including HRP Goat Anti-Mouse IgG and HRP Goat Anti-Rabbit IgG, were obtained from ABclonal Technology (Hubei, China). MALAT1-IN-1 and Stattic were purchased from MedChemExpress (NJ, USA). Mibolerone (Mib) was purchased from Sigma Aldrich (MO, USA). Charcoal-stripped serum (CSS) was purchased from Biological Industries (Beit Haemek, Israel). Phenol red-free RPMI 1640 was purchased from Gibco (New York, USA).