IL-1 receptor antagonist in saliva; characterization in normal saliva and reduced concentration in Sjo¨gren's syndrome (SS)

Abstract

SUMMARYThe characterization of a salivary factor cross-reacting with IL-1 receptor antagonist (IL-1Ra) is described. The apparent molecular weights of two species were 23 kD, consistent with the secreted peptide (sIL-1Ra), and 20 kD, consistent with the intracellular peptide (icIL-1Ra). It had an inhibitory activity on IL-1-stimulated fibroblasts, which is characteristic of IL-1Ra. Its source was the oral mucosa and not the salivary glands. Saliva from patients with SS contained significantly less IL-1Ra than saliva from controls. The decrease was marked in patients with early dental loss but whose xerostomia was still partial. In SS, the salivary IL-1/IL-1Ra imbalance may promote inflammatory lesions in the mouth and impede mucosal cell differentiation.

Salivary Immunosuppressive Cytokines IL-10 and IL-13 Are Significantly Elevated in Oral Squamous Cell Carcinoma Patients

“…IL-1RA is an anti-inflammatory cytokine that competes with IL-1α and IL-1β for binding to the IL-1 receptor (40). IL-1RA has been found to be present in saliva in significantly higher amounts than in peripheral blood and is generally secreted by oral keratinocytes in biologically active form (41). Linkov et al carried out a comprehensive serum-based biomarker evaluation, where they found IL-1RA levels to be significantly raised in head and neck squamous cell carcinoma (42).…”

Lipoxin A4 inhibits immune cell binding to salivary epithelium and vascular endothelium

“…B lymphocytes make up ϳ20% of the infiltrating cell population and monocytes/macrophages are also present (50). Infiltrating lymphocytes produce proinflammatory cytokines that have been shown to play a role in the pathogenesis of SS (10,21,35,71,73). During the evolution of the inflammatory response in SS, an array of adhesive interactions occurs between immune cells and target tissues (2,22,75,89).…”

IL‐1 family in breast cancer: Potential interplay with leptin and other adipocytokines

“…In contrast, the inflammatory site is more likely unbalanced in favor of IL-1, especially in severe lesions [27] and insufficient production of endogenous IL-1ra may contribute to the pathogeny of these conditions [see [22] for more details].…”