Dysregulated Pro-inflammatory and Anti-inflammatory Cytokine Responses to Microbe-associated Molecular Patterns in X-linked Chronic Granulomatous Disease

Abstract

Background/aim: Chronic granulomatous disease (CGD) is a hereditary immune deficiency caused by mutations in nicotinamide adenine dinucleotide phosphate oxidase subunits. X-linked CGD caused by mutations in gp91^phox is characterized by recurrent bacterial and fungal infections and by an increased incidence of autoimmunity and inflammatory bowel disease (IBD). The concurrent occurrence of microbial infection, autoimmunity, and IBD suggests the presence of complicated profiles of cytokines in patients with CGD. However, the pro-inflammatory and anti-inflammatory cytokine responses to microbe-associated molecular patterns (MAMPs) are poorly defined in patients with CGD.

Patients and methods: We evaluated the cytokine and chemokine profiles in two patients with X-linked CGD. Peripheral blood mononuclear cells (PBMCs) were isolated and stimulated with various bacterial and fungal MAMPs.

Results: Production of C-X-C motif chemokine ligand 8, interleukin-6 (IL-6), IL-10, and tumor necrosis factor-α was enhanced by PBMCs isolated from patients with X-linked CGD as compared with those from healthy controls when stimulated with bacterial and fungal MAMPs.

Conclusion: A dysregulated balance between pro-inflammatory and anti-inflammatory cytokines may contribute to the manifestations of recurrent infection, autoimmunity, and IBD in patients with X-linked CGD.

Keywords: Microbe-associated molecular patterns; chronic granulomatous disease; cytokines.

Figure 1

Production of cytokines and chemokines associated with innate immunity by peripheral blood mononuclear cells (PBMCs) isolated from healthy controls and patients with X-linked chronic granulomatous disease (CGD). PBMCs (1×10⁶ cells/ml) isolated from healthy controls (n=14 or 12) and patients with X-linked CGD (n=2) were stimulated with FK156 (20 μg/ml), MDP (20 μg/ml), PAM (1 μg/ml), LPS (1 μg/ml), zymosan (5 μg/ml), curdlan (50 μg/ml), HKCA (1×10⁸ cells/ml), HKSC (1×10⁸ cells/ml), or MSU (100 μg/ml) for 72 h. Culture supernatants were subjected to enzyme-linked immunosorbent assay to measure (A) CXCL8, (B) IL-1β, (C) IL-6, and (D) TNF-α concentrations. Results are presented as the mean±standard error of mean. Each dot presents a value obtained from each subject. *p<0.05, **p<0.01, as compared with healthy control-derived PBMCs stimulated with each ligand. MDP: Muramyl dipeptide; PAM: PAM3CSK4; LPS: lipopolysaccharide; HKCA: heat-killed Candida albicans; HKSC: heat-killed Saccharomyces cerevisiae; MSU: monosodium urate crystals; CXCL8: C-X-C motif chemokine ligand 8; IL-1β: interleukin-1β; TNF-α: tumor necrosis factor-α.

Figure 2

Production of cytokines, IgG1, and IgG4 by peripheral blood mononuclear cells (PBMCs) isolated from healthy controls and patients with X-linked chronic granulomatous disease (CGD). PBMCs (1×10⁶ cells/ml) isolated from healthy controls (n=18, 16, 14, or 12) and patients with X-linked CGD (n=2) were stimulated with FK156 (20 μg/ml), MDP (20 μg/ml), PAM (1 μg/ml), LPS (1 μg/ml), zymosan (5 μg/ml), curdlan (50 μg/ml), HKCA, 1×10⁸ cells/ml), HKSC (1×10⁸ cells/ml), or MSU (100 μg/ml) for 72 h or seven days. Culture supernatants were subjected to enzyme-linked immunosorbent assay to measure (A) IFN-γ, (B) IL-10, (C) IgG1, and (D) IgG4 concentrations. Results are presented as the mean±standard error of mean. Each dot presents a value obtained from each subject. *p<0.05, **p<0.01, compared with healthy control-derived PBMCs stimulated with each ligand. MDP: Muramyl dipeptide; PAM: PAM3CSK4; LPS: lipopolysaccharide; HKCA: heat-killed Candida albicans; HKSC: heat-killed Saccharomyces cerevisiae; MSU: monosodium urate crystals; IFN-γ: interferon-γ; IL-10: interleukin-10; IgG1: immunoglobulin G1; IgG4: immunoglobulin G4.