Impaired Maturation of Monocyte Derived Dendritic Cells from Birch Allergic Individuals

Abstract

RATIONALE: To study whether monocytes differentiated dendritic cells (DCs) from healthy and birch allergic asthmatic individuals differs in their phenotypic receptor expression and cytokine secretion. METHODS: Monocytes were isolated from separated mononuclear cell from allergic (n= 14) and healthy (n=14) individuals. Differentiated DCs were further pulsed by adding birch and cat allergens and LPS, and non- stimulated DCs were included as controls. DCs stained with anti-CD83, -CD80, - CD1a; -CD86, -CD11c and - HLA DR antibodies were analysed by four-colour flow cytometry. Cytokines and chemokines were measure in DCs supernatant in a Bio-Plex Human 7-plex assay, including IL-6, IL-8, IL-10, IL-12p70, MCP-1/MCAF, TNF- and MIP-1. RESULTS: The percentages of DCs expressing HLA-DR, CD80, CD86, CD83, CD1a and CD11c were similar in cells from allergic and healthy individuals. However, while cells from healthy donators showed similar activation of the CD80 and double CD80/CD86 receptors after stimulation as compared to non-stimulated cells, birch allergen was unable to increase CD80 and double CD80/CD86 expression on cells from allergics. Levels of IL-12p70 and TNF-α were higher in supernatant from non-stimulated cells from healthy and further increased after birch and LPS stimulation. After cat stimulation, increased levels of IL-8, IL-10, MIP-1 and MCP-1 were detected in samples from allergic while the levels after birch stimulation. CONCLUSIONS: Our results suggest an impaired specific maturation of DCs from birch allergic individuals in association to birch specific immune responses. Lower secretion of IL-12p70 indicated that the specific Th1 function seems to be affected in allergics.