Since we detected IL-10 production following splenocyte activation with rSm19, we hypothesize here that this cytokine might be regulating Th2 responses and/or preventing the development of highly polarized Th1 responses and therefore, reducing inflammation and liver pathology [30],[31]. In order to investigate the impact of rSm29 vaccination on scavenger receptor-like molecules would decrease pathogen recognition and cell adhesion by host cells. Additionally, we found down-regulated genes involved with parasite carbohydrate and lipid metabolism, protein biosynthesis, intracellular signaling cascade, among others (Table S1). this disease has experienced more failures than successes, encouraging results have recently been obtained using membrane-spanning protein antigens from the tegument of Our group recently identified Sm29, another antigen that is present at the adult worm tegument surface. In this study, we investigated murine cellular immune responses to recombinant (r) Sm29 and tested Ixazomib citrate this protein as a vaccine candidate. Methods and Findings We first show that Sm29 is located on the surface of adult worms and lung-stage schistosomula through confocal microscopy. Next, immunization of mice with rSm29 engendered 51%, 60% and 50% reduction in adult worm burdens, in intestinal eggs and in liver granuloma counts, respectively (p 0.05). Protective immunity in mice was Rabbit polyclonal to ZNF131 associated with high titers of specific anti-Sm29 IgG1 and IgG2a and elevated production of IFN-, TNF- and IL-12, a typical Th1 response. Gene expression analysis of worms recovered from rSm29 vaccinated mice relative to worms from control mice revealed a significant (q 0.01) down-regulation of 495 genes and up-regulation of only 22 genes. Among down-regulated genes, many of them encode surface antigens and proteins associated with immune signals, suggesting that under immune attack schistosomes reduce the expression of critical surface proteins. Conclusion This study demonstrates that Sm29 surface protein is a new vaccine candidate against schistosomiasis and suggests that Sm29 vaccination associated with other protective critical surface antigens is the next logical strategy for improving protection. Author Summary Schistosomiasis is the most important human helminth infection in terms of morbidity and mortality. Although the efforts to develop a vaccine against this disease have experienced failures, a new generation of surface antigens revealed by proteomic studies changed this scenario. Our group has characterized the protein Sm29 described previously as one of the most exposed and expressed antigens in the outer tegument of tegument composition identified Sm29 as one of the integral proteins to be consistently found in the outer surface [11]. Therefore, the next step would be to investigate humoral and cellular immune responses induced by Sm29 in vaccinated mice and protection studies. Herein, we determined that Sm29 is present on the tegument of lung-stage and male and female adult worms of by confocal microscopy. Besides, rSm29 induced a Th1-type of immune response in mice Ixazomib citrate and reduction in worm burden and liver pathology. Methods Mice and parasites C57BL/6 and TLR4 KO female mice, 6C8 weeks old, were obtained from the Federal University of Minas Gerais (UFMG) animal facility. All procedures involving animals were approved by the local Ethics Committee on Animal Care (CETEA-UFMG). Cercariae of (LE strain) were maintained routinely in snails at Rene Rachou Research Center (Fiocruz, Brazil) and prepared by exposing infected snails to light for 2 hrs to induce shedding of parasites. Cercarial numbers and viability were determined using a light microscope prior to infection. The protocols involving animals used in this study were approved by the Federal University of Minas Gerais Ethics Committee in Animal Experimentation (CETEA No. 023/2005). Antigen preparation The recombinant Sm29 was produced and purified as described previously [8]. Briefly, the Sm29 cDNA fused with a C-terminal 6x histidine was produced in using the pET21a expression vector (Novagen, NJ, USA). The recombinant Sm29 was purified in an affinity column and dialyzed against PBS pH 7.0. Immunolocalization of Sm29 in male, female and lung-stage schistosomula of S. snails exposed to light for two hours were transformed mechanically in skin-stage schistosomula according Ixazomib citrate to Ramalho-Pinto et al [13]. First, cercariae were incubated on ice for 30 minutes and centrifuged for 3 minutes, 1000 rpm, 4C. The cercariae were resuspended in 1ml of cold ELAC (Earle’s salts plus lactalbumin hydrolysate) contain.