Selecting specific bio-markers and researching mechanisms of immune regulation from inhalation injury (ILI) and traumatic lung injury (TLI) based on single cell RNA sequencing technology

To profile the circulating immunological traits of patients with traumatic lung injury (TLI) and inhalation injury (ILI),providing a new direction for the depth research of the pathogenesis, and providing new immune-related targets for diagnosis of the severity of lung injury and treatment, we performed scRNA-seq of neutrophil and PBMCs from fresh circulating blood from 3 patients with TLI and 3 patients with ILI at longitudinal timepoints,as well as peripheral blood from 3 health controls(HCs).We conclude that at different stages of the course of TLI or ILI, there are differences in the proportion of immune cell subsets. PMN function is disordered in the acute stage and the progressive stage, and immature neutrophil subsets of different degrees appear which indicates acute myeloid cells are generated. At the same time, the interactions among the subpopulations of myeloid cells are significantly enhanced during the acute phase, which synergistically promote the development of TLI or ILI. Overall design: We performed single-cell transcriptomic sequencing (BD Rhapsody) on neutrophil and PBMCs extracted from the fresh circulating blood from 3 patients with TLI and 3 patients with ILI at longitudinal timepoints,as well as peripheral blood from 3 health controls(HCs). Three time points are chosen by clinical conditions of patients with TLI or ILI: day 1 post hospital admission, day 3 post hospital and the day before discharged which matched to acute stage, progressive stage and convalescence.