Nattectin a fish C-type lectin drives Th1 responses in vivo: Licenses macrophages to differentiate into cells exhibiting typical DC function

Abstract

Considerable efforts are currently focused on the biology of DC in view of their possible clinical use as adjuvant for the generation of antigen-specific immunity and lifelong immunologic memory or for the treatment of tumors. We assessed the role of Nattectin a C-type lectin identified in the Thalassophryne nattereri fish venom in DC maturation. Nattectin induced a significant neutrophilic recruitment into peritoneal cavity of mice, followed by macrophages, with lipidic mediators and IL-12 p70 synthesis. Macrophages derived from 7day-Nattectin mice were CD11c+CD11b(low)Ly6(high)F4/80R(high) and express high levels of MHC class II and CD80 molecules. Culture of peritoneal exudates derived macrophages from 7day Nattectin-mice and immature BMDCs with Nattectin markedly increased the surface expression of CD40, CD80, CD86, and MHC class II in a dose-dependent manner, and the production of MMP-2 and MMP-9 distributed in nucleus and cytoplasm of cells, that was associated with strong activity in the culture supernatant. Nattectin treated DCs secreted IL-12 p70 and IL-10. The Nattectin-treated BMDC or macrophage-derived DCs were highly efficient at Ag capture. The specific immune response elicited by Nattectin was characterized by the production of specific antibodies IgG1 and mainly IgG2a with IL-10 and IFN-γ synthesis by splenic cells. These results enable us to address that Nattectin induces the recruitment of Ly6C(high) monocytes into the peritoneum, which exhibit a pro-inflammatory profile, where they differentiate into proliferating F4/80R(high) macrophages. Macrophage-derived DCs mature in the presence of the cytokine milieu generated against Nattectin, exhibiting T cell co-stimulatory molecule expression and induced a Th1 polarized response.

RNA-seq analysis of mucosal immune responses reveals signatures of intestinal barrier disruption and pathogen entry following Edwardsiella ictaluri infection in channel catfish, Ictalurus punctatus

“…Indeed, the captured pattern is far more characteristic of immune evasion driven by E. ictaluri secreted effectors. We observed dramatic down-regulation (>30-fold at 3 h post infection) of nattectin, a fish C-type lectin, which has been demonstrated to induce the recruitment of specific subsets of monocytes which possess dendritic cell (DC) functions [60]. Interestingly, in one of the few previous studies of intestinal responses to infection in fish, nattectin levels were observed to be higher in disease-resistant gilthead sea bream [16].…”

Differential expression of long non-coding RNAs in three genetic lines of rainbow trout in response to infection with Flavobacterium psychrophilum

“…2). Role of these correlated proteins in the immune system has already been characterized in different species35363738394041. Several studies have also reported correlated expression of several immune related protein-coding genes with a single lncRNA13.…”

Identification of Surrogates of Protection against Yersiniosis in Immersion Vaccinated Atlantic Salmon

“…Likewise, bacterial infection caused by Aeromonas salmonicida induced the upregulation of multiple C-type lectins in the liver of Atlantic salmon [21]. More recently, nattectin, a C-type lectin identified in the fish Thalassophryne nattereri , when administered to mice was found to increase the production of pro-inflammatory cytokines that subsequently drive Th1 responses in vivo [22]. In the present study a potential lectin-induced Th1 response may contribute to host protection especially given the facultative intracellular nature of Y. ruckeri [20].…”