STAT4 Knockout Protects LPS-induced Lung Injury by Increasing of MDSC and Promoting of Macrophage Differentiation.

•STAT4 knockout(KO) decreases the lethality after lipopolysaccharide instillation.•STAT4 KO ameliorates lipopolysaccharide-induced lung injury.•CD11b+Gr-1+ myeloid cells increased in blood of STAT4 KO mice.•Macrophages increased and neutrophils decreased in lung of STAT4 KO mice.•M1-like cytokines reduced while M2-like cytokine increased in STAT4 KO mice.