Effects of C-type lectin receptors on functional regulation of dendritic cells / 中国免疫学杂志

Dendritic cells are the most potent professional antigen presenting cells.The expression of C-type lectin receptors (CLR) contributes to the intake of glycoprotein and identification of microbial antigens,which results in antigen information presented to T and B lymphocytes and the ensuing adaptive immune response.The process plays an important role in antifungal or anti-parasitic infection immunity,allergic reactions and tumor immunity.Therefore,it is of great significance to explore the effect of C-type lectin receptors on the regulation of DC function and the development of diseases.The review focuses on the recent research findings on the effect of CLR members on the functional regualtion of DC.

La estimulación de TLR, receptores tipo NOD y dectina-1 en neutrófilos humanos induce la producción de citocinas proinflamatorias / Stimulation of TLRs, Nod-like receptors and Dectin-1 in neutrophils induces the production of proinflammatory cytokines

Objetivo: evaluar la expresión y la función de receptores de reconocimiento de patrones como los de tipo Toll y los de tipo NOD, RIG-I/MDA5, la dectina-1 y moléculas adaptadoras, en neutrófilos humanos. Métodos: a partir de sangre periférica de individuos sanos se purificaron y cultivaron neutrófilos en el medio RMPI-1640, en presencia o ausencia de los agonistas específicos de los receptores de interés. La expresión de los receptores de reconocimiento de patrones se determinó por RT-PCR y la secreción de citocinas proinflamatorias, por ELISA. Resultados: los neutrófilos expresan un amplio espectro de receptores de reconocimiento de patrones y de moléculas adaptadoras. La estimulación de TLR4, TLR5, TLR7/8 induce la secreción de IL-1β e IL-6; la activación de la dectina-1 induce una alta producción de TNF-α, pero bajos niveles de IL-1β e IL-6. Conclusión: los neutrófilos expresan un amplio número de receptores de reconocimiento de patrones y su activación lleva a la expresión de diferentes citocinas proinflamatorias.

Objective: To evaluate the expression and function of pattern recognition receptors such as Toll-like receptors, RIG-I/MDA5, NOD-like receptors, Dectin-1 and adaptor proteins, in human neutrophils. Methods: Neutrophils from peripheral blood of healthy individuals were purified and cultured in RPMI-1640, in the presence or absence of specific agonists of the receptor of interest. The expression of pattern recognition receptors was determined by RT-PCR and the secretion of proinflammatory cytokines, by ELISA. Results: We observed that neutrophils express diverse patterns recognition receptors and adaptor molecules. Stimulation of TLR4, TLR5 and TLR7/8 induces the production of IL-1β and IL-6, and activation of Dectin-1 leads to secretion of high levels of TNF-α, but low levels of IL-1β and IL-6. Conclusion: Neutrophils express a large number of pattern recognition receptors and their activation leads to the expression of proinflammatory cytokines.

The Innate Immune Response in House Dust Mite-Induced Allergic Inflammation

Hypersensitivity to house dust mite (HDM; Dermatophagoides sp.) allergens is one of the most common allergic responses, affecting up to 85% of asthmatics. Sensitization to indoor allergens is the strongest independent risk factor associated with asthma. Additionally, >50% of children and adolescents with asthma are sensitized to HDM. Although allergen-specific CD4+ Th2 cells orchestrate the HDM allergic response through induction of IgE directed toward mite allergens, activation of innate immunity also plays a critical role in HDM-induced allergic inflammation. This review highlights the HDM components that lead to activation of the innate immune response. Activation may due to HDM proteases. Proteases may be recognized by protease-activation receptors (PARs), Toll-like receptors (TLRs), or C-type lectin receptors (CTRs), or act as a molecular mimic for PAMP activation signaling pathways. Understanding the role of mite allergen-induced innate immunity will facilitate the development of therapeutic strategies that exploit innate immunity receptors and associated signaling pathways for the treatment of allergic asthma.