Anti-IL17A (N-terminal) polyclonal antibody

Interleukin-17 (IL17) family cytokines are well known for having pro-inflammatory actions as important mediators of mucosal immune responses and are tightly regulated by various kinds of signals. However, most studies of IL17 genes have focused on mammals, and much less is known about IL17 genes in fish species. To better understand the scope and actions of the IL17 gene family in common carp, we characterized seven IL17 gene homologs from genomic and transcriptomic databases that could be classified into three subclasses according to different comparative genomic analyses. Phylogenetic analysis revealed that most IL17s are highly conserved, though recent gene duplication and gene loss events do exist. Through observation, we found that IL17D has undergone gene duplication in common carp and that all the IL17E genes were lost in vertebrates except mammals. The expression patterns of IL17 genes in common carp were examined during early developmental stages and in various healthy tissues, and the results indicated that most IL17 genes are ubiquitously expressed during early development and show particular tissue-specific expression in various healthy tissues, with relatively high levels in the spleen, liver, and kidney. To gain insights into the mucosal actions of inflammatory processes, the expression profiles of IL17 genes in gills from common carp were investigated after experimental challenge with Aeromonas hydrophila. After A. hydrophila infection, most IL17 genes were upregulated at 4 h postinfection in the gill and then gradually declined, while IL17A/F2 and IL17N were generally upregulated at 12 h postinfection, and IL17D2 maintained an increasing tendency. In contrast, IL17D showed the third phenomenon, rising expression, suggesting that immunogenes have different response strategies to bacterial invasion. Overall, the expression of IL17 in unstimulated tissues and toxicity attack test results demonstrated that these genes play critical roles under normal conditions and during bacterial infection. Moreover, this common carp IL17 gene family research provides a genomic resource for future studies on IL17 gene evolution, fish disease management and immune regulation.

Background: Mycobacterium avium complex (MAC)-lung disease (LD) is increasing in patients without human immunodeficiency virus infection. However, data on host vulnerability to MAC-related immune responses, and in particular the interleukin (IL)-23/IL-17 axis, are lacking. Methods: We enrolled 50 patients with MAC-LD, 25 age-matched patients with tuberculosis (TB) and 25 controls. We measured levels of plasma cytokines, and studied IL-12/IL-17 responses in macrophage and lymphocyte activation to MAC. Results: The plasma level of IL-17 in the MAC group was higher than in the TB and control groups. In in-vitro macrophage stimulation, the expression of IL-23 in macrophages was similar in the patients with MAC-LD and controls, although the expression of IL-12 p40 was lower in the patients with MAC-LD. In assays of lymphocyte activation, IL-17 was induced by MAC-primed macrophages, but its level was lower in the patients with MAC-LD and TB than in the controls. The expression of programmed death (PD)-1 receptor was higher in CD4(+) IL17A(+) lymphocytes in the patients with MAC-LD, and the production of IL-17 was significantly increased by blockade of PD-1 and PD-ligand 1. Conclusions: MAC induced a similar expression of IL-23 from macrophages in the patients with MAC-LD compared to the controls, but a lower expression of IL-17 from lymphocytes, which may be through an increased expression of PD-1. The macrophage response of IL-12 p40 was stronger than that of IL-12 p70, and higher in the controls during MAC disease, which may suggest another kind of MAC-related immune evasion.