Macrophage Receptors and Innate Immunity: Insights from Dectin‐1

Abstract

The innate ability of macrophages to induce an immune response to pathogens is dependent upon germline encoded pattern recognition receptors which recognise conserved microbial structures. These receptors not only mediate pathogen recognition, but promote microbial uptake and killing and the induction of infl ammatory responses. Although the recently described Toll-like receptors (TLR) have been shown to play a central role in mediating the intracellular signals involved, the non-TLRs also have important functions in these processes. Once such receptor is Dectin-1, a myeloid expressed signalling C-type lectin-like receptor which is involved in the innate recognition of fungal pathogens. Dectin-1 can induce a variety of cellular responses, including phagocytosis, the respiratory burst and cytokine production. These responses are mediated through novel signalling pathways induced from the cytoplasmic immuno-receptor tyrosine based activation-like motif of the receptor. Although the in vivo role of Dectin-1 has still to be fully elucidated, there is emerging evidence that this receptor plays a role in the infl ammatory response to pulmonary fungal pathogens and that it is involved in certain autoimmune and respiratory diseases.

Understanding the Mechanisms Controlling Leishmania amazonensis Infection In Vitro: The Role of LTB4 Derived From Human Neutrophils

“…Additionally, treatment of human neutrophils with LTB 4 in vitro potentiates the TLR response [ 42 ]. Similar results were also obtained for the pattern recognition receptor dectin-1, a C-type lectin receptor that recognizes β-glucans [ 43 ] and whose expression is controlled by LTB 4 in mouse macrophages [ 44 ].…”

Characterization and immunological effect of outer membrane vesicles from Pasteurella multocida on macrophages

“…This discovery supports the notion that P. multocida OMVs contribute to macrophage proliferation and activation in an in vitro setting. Additionally, upon sensing pathogenic signals, macrophages release cytokines to facilitate both innate and adaptive immune responses (Brown 2006 ; Weiss and Schaible 2015 ). Macrophages can be categorized into M1 and M2 types, each of which is involved in distinct immune responses.…”

Caracterização das bases moleculares da suscetibilidade imunológica à infecção por Candida albicans

“…O receptor Dectina-1 é capaz de interagir com β-(1,3)-glicana induzindo vários eventos celulares, como a explosão respiratória, fagocitose e endocitose, produção de metabólitos do ácido araquidônico, maturação de células dendríticas e produção de várias citocinas e quimiocinas (Brown, 2006). Para que ocorram estes eventos, em alguns casos basta a interação com Dectina-1, porém em outros é necessário que ocorra a ligação também com os TLRs associados à proteína adaptadora MyD88 (Brown, 2006;Dennehy et al, 2008).…”

“…Para que ocorram estes eventos, em alguns casos basta a interação com Dectina-1, porém em outros é necessário que ocorra a ligação também com os TLRs associados à proteína adaptadora MyD88 (Brown, 2006;Dennehy et al, 2008). A sinalização por Dectina-1 ocorre via Syk e a molécula adaptadora CARD9, e essa via é capaz de induzir IL-2 e IL10 em células dendríticas.…”