Inflammation resolution circuits are uncoupled in acute sepsis and correlate with clinical severity
Bakr Jundi, Do-Hyun Lee, Hyungkook Jeon, Melody G. Duvall, Julie Nijmeh, Raja-Elie E. Abdulnour, Mayra Pinilla-Vera, Rebecca M. Baron, Jongyoon Han, Joel Voldman, Bruce D. Levy
Bakr Jundi, Do-Hyun Lee, Hyungkook Jeon, Melody G. Duvall, Julie Nijmeh, Raja-Elie E. Abdulnour, Mayra Pinilla-Vera, Rebecca M. Baron, Jongyoon Han, Joel Voldman, Bruce D. Levy
View: Text | PDF
Research Article Inflammation Pulmonology

Inflammation resolution circuits are uncoupled in acute sepsis and correlate with clinical severity

Abstract

Sepsis is a critical illness characterized by dysregulated inflammatory responses lacking counter-regulation. Specialized proresolving mediators are agonists for antiinflammation and for promoting resolution, and they are protective in preclinical sepsis models. Here, in human sepsis, we mapped resolution circuits for the specialized proresolving mediators resolvin D1 and resolvin D2 in peripheral blood neutrophils and monocytes, their regulation of leukocyte activation and function ex vivo, and their relationships to measures of clinical severity. Neutrophils and monocytes were isolated from healthy subjects and patients with sepsis by inertial microfluidics and resolvin D1 and resolvin D2 receptor expression determined by flow cytometry. The impact of these resolvins on leukocyte activation was determined by isodielectric separation and leukocyte function by stimulated phagolysosome formation. Leukocyte proresolving receptor expression was significantly higher in sepsis. In nanomolar concentrations, resolvin D1 and resolvin D2 partially reversed sepsis-induced changes in leukocyte activation and function. Principal component analyses of leukocyte resolvin receptor expression and responses differentiated sepsis from health and were associated with measures of sepsis severity. These findings indicate that resolvin D1 and resolvin D2 signaling for antiinflammation and resolution are uncoupled from leukocyte activation in early sepsis and suggest that indicators of diminished resolution signaling correlate with clinical disease severity.

Authors

Bakr Jundi, Do-Hyun Lee, Hyungkook Jeon, Melody G. Duvall, Julie Nijmeh, Raja-Elie E. Abdulnour, Mayra Pinilla-Vera, Rebecca M. Baron, Jongyoon Han, Joel Voldman, Bruce D. Levy

×

Figure 3

Upregulation of SPM receptors DRV1, ALX, and DRV2 in monocytes in sepsis.

Options: View larger image (or click on image) Download as PowerPoint
Upregulation of SPM receptors DRV1, ALX, and DRV2 in monocytes in sepsis...
Monocytes were isolated from were isolated from 50 μL of peripheral blood using the closed-loop operation of spiral microfluidics system. (A) Flow cytometry contour plots identifying the various FSC+SSC–CD45+CD66b– monocyte subsets based on CD16 and CD14 surface expression (classical, intermediate, and nonclassical monocytes) in isolated blood from healthy subjects and patients with sepsis. Classical monocytes were defined as FSC+SSC–CD45+CD66b–CD16loCD14hi, intermediate monocytes as FSC+SSC–CD45+CD66b–CD16hiCD14hi, and nonclassical monocytes as FSC+SSC–CD45+CD66b–CD16hiCD14lo. (B) Representative flow cytometry histogram plots (upper panel) and violin graphs (lower panel) of classical monocytes (CM) surface receptor expression of DRV1, ALX, and DRV2 in control (fluorescence minus 1, light gray), health (dark gray), and sepsis (crimson). Health, n = 4; Sepsis, n = 12–13. (C) Mean fluorescence intensity (MFI) of surface receptor expression of DRV1, ALX, and DRV2 among all monocyte subsets: classical monocytes (CM, crimson), intermediate monocytes (IM, beige), and nonclassical monocytes (NCM, blue) in health (n = 4) and sepsis (n = 12–13). (D) Representative flow cytometry contour plots of pHrodo+ classical (CM, crimson), intermediate (IM, beige), and nonclassical (NCM, blue) monocytes from patients with sepsis incubated with vehicle (<0.01% EtOH), RvD1 (100 nM), or RvD2 (100 nM) for 15 minutes at 37°C, n = 10–11. (E) Concentration-response curve of the frequency of pHrodo+ intermediate monocytes varying concentrations of RvD1 (circle, crimson), RvD2 (square, crimson), or vehicle (mean value, dashed gray line). Sepsis, n = 6. Values are expressed as the mean ± SEM. *P < 0.05 for sepsis versus health by unpaired, 2-tailed t test; **P < 0.05 for vehicle versus RvD1 or RvD2 by paired, 2-tailed t test; ‡P < 0.05 for IM versus CM by paired, 2-tailed t test; ‡‡P < 0.05 NCM versus IM by paired, 2-tailed t test.