Elevated expressions of myeloid-related proteins-8 and -14 are danger biomarkers for lupus nephritis

• Published in: Lupus 2016-01, Vol.25 (1), p.38-45
• Main Authors: Tantivitayakul, P, Benjachat, T, Somparn, P, Leelahavanichkul, A, Kittikovit, V, Hirankarn, N, Pisitkun, T, Avihingsanon, Y
• Format: Article
• Language: English
• Subjects: Adult; ATP-Binding Cassette Transporters - blood; ATP-Binding Cassette Transporters - genetics; Biomarkers; Biomarkers - blood; Biopsy; Blood; Calgranulin B - blood; Calgranulin B - genetics; Cross-Sectional Studies; Gene expression; Glomerulonephritis; Humans; Immune response; Immunohistochemistry; Immunosuppressive Agents - therapeutic use; Inflammation; Innate immunity; Kidney - drug effects; Kidney - metabolism; Kidney - pathology; Leukocytes (neutrophilic); Leukocytes - drug effects; Leukocytes - metabolism; Longitudinal Studies; Lupus; Lupus nephritis; Lupus Nephritis - blood; Lupus Nephritis - diagnosis; Lupus Nephritis - drug therapy; Lupus Nephritis - genetics; Macrophages; Nephritis; Prospective Studies; Proteins; Real-Time Polymerase Chain Reaction; RNA, Messenger - blood; Severity of Illness Index; Treatment Outcome; Up-Regulation; Young Adult
• ISSN: 0961-2033; 1477-0962
• DOI: 10.1177/0961203315598015

Myeloid-related proteins, MRP-8 and -14, which have been identified as molecules that mediate the danger signaling in innate immune response, are also known as the DAMPs (damage associated molecular pattern molecules). The proteins were found in infiltrating macrophages and neutrophils at inflammatory sites. Their expression was correlated with severe forms of glomerulonephritis. Therefore, this study examined whether or not MRP-8 and -14 can be used as biomarkers for identifying severely active lupus nephritis (LN). Total blood leukocyte samples and renal biopsy tissues from a prospective cohort of LN patients were used to determine mRNA and protein expression levels of MRP-8 and -14. The mRNA levels of MRP-8 and -14 in total blood leukocytes were significantly higher in active LN patients than quiescent LN patients and healthy controls. Moreover, the mRNA levels of MRP-8 and -14 in the total blood leukocytes and kidney tissues were significantly correlated with therapeutic response and the mRNA expression levels in the kidney were associated with an early loss of the kidney function. MRP-8 and -14 can be used as non-invasive prognostic biomarkers in patients with LN.