Histamine improves antigen uptake and cross-presentation by dendritic cells

AMARAL MARÍA MARTA; DAVIO CARLOS; SALAMONE GABRIELA; CAÑONES CRISTIAN; GEFFNER JORGE; VERMEULEN MÓNICA

JOURNAL OF IMMUNOLOGY

American Association of Immunologists

Lugar: Baltimore; Año: 2007 p. 3425 - 3433

0022-1767

Previous studies have shown that histamine is able to modulate the function of dendritic cells. Histamine seems to be required for the normal differentiation of DCs. Moreover, it is capable to stimulate the chemotaxis of immature DCs and to promote the differentiation of T CD4+ cells into a TH2 profile. In this study, we analyzed whether histamine was able to modulate endocytosis and cross-presentation mediated by immature DCs. Our results show that both functions are stimulated by histamine. Endocytosis of soluble HRP and FITC-OVA, and cross-presentation of soluble OVA were markedly increased by histamine. Interestingly, stimulation of endocytosis and cross-presentation appeared to be mediated through different histamine receptors. In fact, the enhancement of endocytosis was prevented by the H2R antagonist cimetidine while the stimulation of cross-presentation was prevented by the H3R/H4R antagonist thioperamide. Of note, contrasting with the observations made with soluble antigens, we found that histamine did not increase neither the uptake of ovalbumin-attached to latex beads, nor the cross-presentation of ovalbumin immobilized on latex beads. This suggests that the ability of histamine to increase endocitosis and cross-presentation is dependent on the antigen form and/or the mechanisms through which the antigen is internalized by DCs. Our results support that histamine may favor cross-presentation of soluble allergens by DCs enabling the activation of allergen-specific T CD8+ cells, which appears to play an important role in the development of allergic responses in the airway.