The role of serum myeloid-related protein 8/14 complex in Henoch–Schönlein purpura nephritis

Abstract

Myeloid-related protein (MRP) 8/14 complex is a marker of monocyte and neutrophil activation. We evaluated whether serum MRP8/14 complex is associated with clinical manifestations and pathological findings of Henoch-Schönlein purpura nephritis (HSPN). Patients were divided into two groups based on serum MRP8/14 complex levels at renal biopsy. Group 1 consisted of 18 HSPN patients with less than median (670 ng/ml) MRP8/14 complex levels, and Group 2 of 12 HSPN patients with greater than median levels. Clinical manifestations, laboratory findings and serum E-selectin levels, as a marker of vascular endothelial cell dysfunction, as well as histological and immunohistochemical findings were investigated for both groups. We also measured MRP8/14 complex levels in disease control and healthy control children. Urinary protein excretions, serum MRP8/14 complex levels, and serum E-selectin levels were all higher in Group 2 than in Group 1 patients. Serum MRP8/14 complex levels were higher in HSPN patients than in controls. Serum MRP8/14 complex levels were strongly associated with serum E-selectin levels. Pathological findings revealed that the proportions of patients with ISKDC grades III, IV and V in Group 2 were higher than in Group 1. Our findings suggest that serum MRP8/14 complex levels might be associated with the severity of renal injury and endothelial cell dysfunction in HSPN patients.

Resistance factors for the treatment of immunoglobulin A nephropathy with diffuse mesangial proliferation

“…showed that serum S100A8/S100A9 expression reflects disease activity in ANCA‐associated vasculitis and glomerulonephritis . Furthermore, we previously reported that macrophage infiltration in glomeruli was a predictor of poor prognosis in HSPN patients . In our present study, serum MRP 8/14 levels at the first renal biopsy were higher than those at the second renal biopsy in IgAN children, and serum MRP 8/14 levels at the second biopsy in Group 2 were higher than those in Group 1.…”

“…Hirono reported that serum MRP8/14 complex levels may be a useful marker of acute Kawasaki disease activity, and the level of MRP8/14‐positive circulating endothelial cells may predict the severity of vasculitis, confirming its important role in distinct inflammatory reactions in the endothelium . With regard to serum MRP8/14 in renal disease, there have been some reports on the expression of MRP 8 and/or MRP 14 in renal tissues in patients with glomerulonephritis . Pepper et al .…”

“…The IF staining results for IgG, IgA, IgM, C1q, C3, C4 and fibrinogen were then examined. To compare biopsies, an immunohistochemical scoring system for the detection of mouse anti‐human PG‐M1(CD68), MRP8 and α‐SMA monoclonal antibodies was used as previously reported …”

“…MRP8 and MRP14 are representative of the predominant calcium‐binding capacity of monocytes and neutrophils in their early stage of differentiation. Further, the renal accumulation of macrophages expressing MRP8 and/or MRP14, and high serum MRP8/14 levels were reported to be associated with the inflammatory activity observed in cases of glomerulonephritis, including Henoch‐Schönlein purpura nephritis (HSPN), antineutrophil cytoplasmic autoantibody (ANCA)‐associated glomerulonephritis, type 2 diabetes and nephropathy . However, there have been a few reports on the relationship between serum MRP8/14 levels and prognosis in IgAN …”

Serum myeloid‐related protein 8/14 in minimal change‐ and glomerulonephritis‐related nephrotic syndrome

“…reviewed reports that expression of MRP8 and MRP14 on macrophages in kidneys affected by each form of GN is associated with the inflammatory activity of the GN . With regard to serum MRP8/14 in renal disease, there have been some reports on the expression of MRP 8 and/or MRP 14 in renal tissues in patients with GN …”