In particular the Wolbachia Surface Protein (WSP) has been shown to elicit https://www.selleckchem.com/products/ABT-888.html innate immune induction via TLR2 and TLR4 activation in both humans and mice [14] and to inhibit apoptosis in neutrophils through inhibition of caspase-3 activity [15]. In this study we investigated whether WSP can also induce innate immune responses in insects, using mosquito cell lines originating from both naturally Wolbachia-uninfected and Wolbachia-infected mosquito species. An additional aim was to identify PAMPs (pathogen associated molecular patterns) that can elicit strong immune

responses in mosquitoes, which could be useful for novel disease control strategies; thus in order to avoid the complications of possible strain-host co-adaptations, we have initially used WSP derived from a nematode Wolbachia rather than from an insect-derived Wolbachia strain. Results WSP is a strong innate immune response

elicitor in An. gambiae cells. In the An. gambiae RGFP966 mouse cells, the antimicrobial peptide-encoding genes Cecropin 1 (CEC1) and Gambicin (GAMB) showed elevated levels of transcription in the presence of WSP compared to negative controls (naïve and proteinase K-treated-pkWSP) [14] and responded in a dosage Entospletinib mw dependent fashion, when different concentrations of WSP up to 5μg/ml were used (Fig1A). Their mRNA levels were increased in the presence of WSP to similar degrees and statistically significant differences were observed for all WSP quantities used. In contrast, Defensin 1 (DEF1) which has been shown to be primarily active against Gram-positive bacteria [16], showed only a small degree of upregulation that was not statistically significant. Increased concentrations of WSP also increased the transcription levels of complement-like gene TEP1, Anopheles Plasmodium-responsive Leucine-rich repeat 1 (APL1) and Fibrinogen 9 (FBN9) (Fig1A). In comparison Rho to the AMPs, TEP1 and APL1 showed a higher induction level with respectively 4 and 5-fold peaks. Significant upregulation was also seen at a concentration of 5μg/ml of WSP for all three genes (p<0.05). This data suggests that in this naturally Wolbachia-uninfected mosquito species, WSP

is capable of inducing the transcription of innate immune factors such as AMPs, complement-like proteins and fibrinogen genes, all of which are involved in anti-parasitic responses in An. gambiae. Figure 1 WSP challenge in mosquito cells. qRT-PCR analysis of AMPs and innate immune genes at 3h post-WSP challenge in 4a3A (A) and Aa23T (B). Increased expression dependent on WSP quantities up to 5μg/ml was detected in all genes tested. Relative expressions were calculated to pkWSP (WSP protein treated with proteinase K) challenged cells and represent the average of 4 biological repeats +/- SE. Statistical analysis where performed using a Wilcoxon rank sum test (*p<0.05, **p<0.01). WSP is a mild innate immune response elicitor in Ae.