Combined Collagen-Induced Arthritis and Organic Dust-Induced Airway Inflammation to Model Inflammatory Lung Disease in Rheumatoid Arthritis

Abstract

Rheumatoid arthritis (RA) is characterized by extra‐articular involvement including lung disease, yet the mechanisms linking the two conditions are poorly understood. The collagen‐induced arthritis (CIA) model was combined with the organic dust extract (ODE) airway inflammatory model to assess bone/joint–lung inflammatory outcomes. DBA/1J mice were intranasally treated with saline or ODE daily for 5 weeks. CIA was induced on days 1 and 21. Treatment groups included sham (saline injection/saline inhalation), CIA (CIA/saline), ODE (saline/ODE), and CIA + ODE (CIA/ODE). Arthritis inflammatory scores, bones, bronchoalveolar lavage fluid, lung tissues, and serum were assessed. In DBA/1J male mice, arthritis was increased in CIA + ODE > CIA > ODE versus sham. Micro‐computed tomography (µCT) demonstrated that loss of BMD and volume and deterioration of bone microarchitecture was greatest in CIA + ODE. However, ODE‐induced airway neutrophil influx and inflammatory cytokine/chemokine levels in lavage fluids were increased in ODE > CIA + ODE versus sham. Activated lung CD11c+CD11b+ macrophages were increased in ODE > CIA + ODE > CIA pattern, whereas lung hyaluronan, fibronectin, and amphiregulin levels were greatest in CIA + ODE. Serum autoantibody and inflammatory marker concentrations varied among experimental groups. Compared with male mice, female mice showed less articular and pulmonary disease. The interaction of inhalation‐induced airway inflammation and arthritis induction resulted in compartmentalized responses with the greatest degree of arthritis and bone loss in male mice with combined exposures. Data also support suppression of the lung inflammatory response, but increases in extracellular matrix protein deposition/interstitial disease in the setting of arthritis. This coexposure model could be exploited to better understand and treat RA–lung disease. © 2019 American Society for Bone and Mineral Research.

Occupational exposure to organic dusts and risk of developing rheumatoid arthritis: findings from a Swedish population-based case–control study

“…We did not consider these exposure in our findings. A recent animal study has, however, shown that inhalation to organic dust exposure from swine confinement feeding facilities led to airway inflammation and arthritis among male mice 24…”

High-throughput analysis of lung immune cells in a combined murine model of agriculture dust-triggered airway inflammation with rheumatoid arthritis

“…Specifically, the combination of the collagen-induced arthritis (CIA) model with a model of airborne biohazard exposure (e.g. agriculture related-organic dust extract/ODE) resulted in augmented arthritis inflammatory score and bone deterioration, increased systemic autoimmunity with increased anti-cyclic citrullinated peptide IgG antibodies, and promotion of prefibrotic inflammatory lung changes in mice [11] consistent with RA-associated lung disease pathophysiology. However, the mechanisms underlying these observations are not known.…”

“…However, insight into how inhalant injury might lead to or exacerbate RA and its pulmonary manifestations, has been limited in the absence of a relevant disease model. Recently a pre-clinical animal model to provide insight into the important cellular players and decipher molecular and potential mechanistic pathways involved in RA-associated inflammatory lung disease was established [11]. Specifically, the combination of the collagen-induced arthritis (CIA) model with a model of airborne biohazard exposure (e.g.…”

Animal models of rheumatoid arthritis‐associated interstitial lung disease

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