High-Throughput Analysis of Lung Immune Cells in a Combined Murine Model of Agriculture Dust-Triggered Airway Inflammation with Rheumatoid Arthritis

We report identification of 14 unique immune cell populations among different treatment groups with single-cell RNA sequencing high throughput technology. We identified (a) 3 unique neutrophil populations including inflammatory, transient and immunosuppressive/autoreactive granulocytes among experimental groups, (b) heterogeneity among 5 macrophage populations including metabolically active, proliferative, differentiating, recruited, and residential with classical (M1) and alternatively (M2)-activated genes, (c) identification of 2 stages of T-lymphocytes (differentiating and effector), a B-cell population and a NK cell cluster, (d) variability in the distribution of cellular clusters among the treatment groups representing RA and RA-associated lung disease (CIA and CIA+ODE groups, respectively), (e) identification of gMDSC and mMDSC populations based on cell surface markers, and (f) identification of unique genes (interferon-related/autoimmune and complement cascade) that are found in a mouse model of RA-associated inflammatory lung disease. This study identified unique populations of lung immune cell clusters differentially ascribed to individual treatment conditions. We identified neutrophil subpopulations and heterogeneous macrophage-monocyte populations in addition to unique genes (interferon-related and complement cascade) that could be contributing to the pathogenesis of RA-associated lung disease. Additionally, this information might inform potential candidates that could be exploited in future investigations examining targeted interventions and the identification of informative disease biomarkers. Overall design: Examination of lung immune cells among treatment groups