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Toxoplasma gondii is a threat for immunocompromized individuals, and no treatment is available for enhancing immunity against infection. Molecular adjuvants may improve the efficacy of DNA vaccine-induced T cell immunity. Here, we report that cocktailed DNA immunization with ROP5 and ROP18 boosted immune responses induced by a single DNA immunization with ROP5 or ROP18, but also that co-administration of molecular adjuvant IL-33 enhanced immune efficacy induced by this cocktailed DNA vaccination. These improved immune responses were characterized by higher Toxoplasma-specific IgG2a titers, Th1 responses associated with the production of IFN-γ, IL-2, IL-12, as well as cell-mediated activity with higher frequencies of CD8+ and CD4+ T cells. More importantly, this enhanced immunity has the ability to confer remarkable protection against a high dose lethal challenge of the T. gondii RH strain and thus against chronic infection with the T. gondii PRU strain. These data show that IL-33 is a promising immunoadjuvant to facilitate humoral as well as cellular immunity in a vaccine setting against T. gondii, and suggest that it should be evaluated in strategies against other apicomplexan parasites.

Background Pancreatic cancer is a highly malignant tumor of the digestive system. Objective Exosomal circular RNA can be used as a biomarker for the early diagnosis of pancreatic cancer. Methods The expression of various differentially expressed circRNAs in pancreatic cancer tissues was analyzed by gene chip, exosome expression was verified by electron microscopy and Western blotting, and the expression of exosomal circRNA in pancreatic cancer cells, tissues, and plasma were determined by quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR). Results Compared with healthy controls, hsa_circ_0006220 and hsa_circ_0001666 were highly expressed in exosomes in the plasma of pancreatic cancer patients. The AUC values were 0.7817 for hsa_circ_0006220, 0.8062 for hsa_circ_0001666, and 0.884 for the combined diagnosis. In addition, clinicopathological features revealed that the expression of hsa_circ_0006220 in plasma exosomes from pancreatic cancer patients was associated with CA19‐9 levels ( p = 0.0001) and lymph node metastasis ( p = 0.0005). The expression of hsa_circ_0001666 was correlated with both tumor size ( p = 0.0157) and CA19‐9 level ( p = 0.0001). Conclusions The high expression of exosomal hsa_circ_0001666 and hsa_circ_0006220 suggests that these can be used as new biomarkers for the diagnosis and treatment of pancreatic cancer.

Toxoplasma gondii is an obligate intracellular parasite, which is responsible for a widely distributed zoonosis. Effective vaccines against toxoplasmosis are necessary to protect the public health. The aim of this study is to evaluate the immune efficacy of DNA vaccines encoding TgMIC5 and TgMIC16 genes against T. gondii infection. The recombinant plasmid pVAX-MIC5 and pVAX-MIC16 were constructed and injected intramuscularly in mice. The specific immune responses and protection against challenge with T. gondii RH tachyzoites were evaluated by measuring the cytokine levels, serum antibody concentrations, lymphocyte proliferation, lymphocyte populations, and the survival time. The protection against challenge with the T. gondii RH tchyzoites and PRU cysts was examined by evaluation of the reduction in the brain cyst burden. The results indicated that immunized mice showed significantly increased levels of IgG, IFN-γ, IL-2, IL-12p70, and IL-12p40 and percentages of CD4+ and CD8+ T cells. Additionally, vaccination prolonged the mouse survival time and reduced brain cysts compared with controls. Mouse groups immunized with a two-gene cocktail of pVAX-MIC5 + pVAX-MIC16 were more protected than mouse groups immunized with a single gene of pVAX-MIC5 or pVAX-MIC16. These results demonstrate that TgMIC5 and TgMIC16 induce effective immunity against toxoplasmosis and may serve as a good vaccine candidate against T. gondii infection.

Toxoplasma gondii, an obligate intracellular protozoan parasite, can cause infect almost all warm-blooded animals and humans. To evaluate the immunogenicity and protective efficacy of T. gondii GRA39 (TgGRA39) in mice by using DNA immunization, we constructed a recombinant eukaryotic plasmid pVAX-TgGRA39. The specific immune responses in immunized mice were analyzed by serum antibody and cytokine measurements, lymphocyte proliferation assays and flow cytometry of T lymphocyte subclasses. Also, protective efficacy against acute and chronic T. gondii infection was assessed by observing the survival time after challenge with the highly virulent T. gondii RH strain (Genotype I) and counting the number of cyst-forming in brain at 4 weeks post-infection with the cyst-forming PRU strain of T. gondii (Genotype II), respectively. Our results showed that DNA immunization with pVAX-GRA39 via intramuscular injection three times, at 2-week intervals could elicit humoral and cellular immune response, indicated by enhanced levels of IgG and IgG2a antibodies (a slightly elevated IgG2a to IgG1 ratio), and increased levels of cytokines IFN-γ, IL-2, IL-12, IL-17A, IL-17F, IL-22 and IL-23 and percentages of CD3+ CD4+ CD8- and CD3+ CD8+ CD4– T cells, in contrast to non-immunized mice. The significant increase in the expression levels of IL-6, TGF-β1, IL-1β, and the transcription factor factors RORγt, RORα, and STAT3 involved in the activation and pathway of Th17 and Tc17 cells, were also observed. However, no significant difference was detected in level of IL-4 and IL-10 (p > 0.05). These effective immune responses had mounted protective immunity against T. gondii infection, with a prolonged survival time (16.80 ± 3.50 days) and reduced cyst numbers (44.5%) in comparison to the control mice. Our data indicated that pVAX-TgGRA39 could induce effective humoral, and Th1-type, Th17, and Tc17 cellular immune responses, and may represent a promising vaccine candidate against both acute and chronic T. gondii infection.

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest malignant tumors with features of matrix barrier caused poor drug permeability, and susceptibility to drug resistance. Herein, a PDAC and its stromal cell dual-targeted photothermal-chemotherapy strategy is explored to loosen the matrix and reverse drug resistance. To achieve this goal, black TiO2-Gd nanocomposites were conjugated with insulin like growth factor 1 (IGF1), and loaded with gemcitabine (GEM) to construct bTiO2-Gd-IGF1-GEM nanoprobes. In vitro results show that under 808 nm near-infrared irradiation, killing effect of the nanoprobes on drug-resistant MIA PaCa-2 cell is 3.3 times than that of GEM alone. In vivo experiments indicate the synergetic photothermal-chemotherapy not only loosens fibrous matrix of pancreatic tumor model, but also dramatically inhibits tumor growth, and almost completely eradicates the tumor after 12 days of treatment. In addition, relaxation rate of the nanoprobes is 8.2 times than commercial contrast agent Magnevist, therefore boosts the signal of magnetic resonance imaging in pancreatic tumor. In conclusion, our results reinforce that the prepared nanoprobes are promising to break matrix barrier and overcome drug resistance in PDAC.

Background: Type 2 diabetes mellitus (T2DM) is a complex metabolic disease closely related to obesity, a growing global health problem. T2DM is characterized by decreased islet beta-cell mass and impaired insulin release from these cells, and this dysfunction is exacerbated by hyperglycemia (glucolipotoxicity). Circular RNAs (circR-NAs) are abnormally expressed and play a regulatory role in T2DM.Objective: This study aimed to evaluate the function and molecular mechanism of hsa_circ_0115355 in the progression of T2DM. Methods: The regulatory effect of hsa_circ_0115355 on INS-1 cell function was assessed under glucolipotoxicity by MTT, flow cytometry analysis, and insulin secretion assay. Dual-luciferase experiments revealed a direct interaction of hsa_circ_0115355 with miR-145 and miR-145 with SIRT1. Furthermore, the regulatory role of the hsa_ circ_0115355/miR-145/SIRT1 axis was verified by examining the function of INS-1.Results: In this study, hsa_circ_0115355 was significantly underexpressed in both patients with T2DM and INS-1 cell lines. This study thus showed that hsa_circ_0115355 inhibits the occurrence and development of T2DM by regulating the expression of SIRT1 by adsorbing miR-145. Conclusion:The underexpression hsa_circ_0115355 is also a potential novel diagnostic marker and therapeutic target for T2DM.

Background: Toxoplasma gondii is known to infect almost all the mammalian including human beings and avian species, with worldwide distribution, and cause serious toxoplasmosis, posing regards with public health problem. The role of microRNAs in the pathogenesis of T. gondii has not been well described. The objective of the present study was to investigate the role of microRNA-155 (miR-155) in mediating innate and adaptive immune responses during T. gondii infection. Methods: The survival and parasite burden in T. gondii-infected miR-155-/- and WT C57BL6 mice were compared. In these two mouse models, ELISA were used for analysis of Th1-associated, Th-2 associated, and Th-17 associated cytokines, and flow cytometry were used for analysis of the subpopulations of NK, NKT, CD8+T, CD4+T cells and Tregs, as well as Ly6Chi inflammatory monocytes and DCs. Proinflammatory mediators and CD8+ T cells responses were also analyzed by using qRT-PCR and flow cytometry, respectively. In the end, the expression of the direct target of miR-155, SHIP-1 and SOCS1 was analyzed by using qRT-PCR.Results: The lack of miR-155 led to increased parasite burden and decreased survival of infected mice in contrast to WT mice. Innate and adaptive immune responses were reduced in the absence of miR-155, associated with diminished Proinflammatory mediators, Th1-associated and Th-2 associated cytokines and accumulation of lymphocyte subpopulations. Also, CD8+ T cells exhaustion was also worsened in the absence of miR-155 via targeting to SHIP-1 and SOCS1, showing as up-regulated recruit of Tregs and expression of PD-1 and, and down-regulated expression of IFN-γ and TNF-α in CD8+ T cells.Conclusion: miR-155 is a critical immune regulator for the control of T. gondii infection, suggesting that miR155 can be explored as a potential molecular target for boosting immunity against T. gondii.