Immune response to inactivated bacterial vector carrying the recombinant K39 antigen of Leishmania infantum in mice

Objective:To evaluate the immunological response elicited by an inactivated bacterial vector carrying the K39 antigen of Leishmania infantum,and a purified antigen.Methods:Mice were subjected to the following treatments:(1)Purified recombinant K39(rK39)protein at a 20μg dose with complete Freund’s adjuvant;(2)Inactivated Escherichia coli(BL21 DE3)carrying the K39 protein at an equivalent total protein content of 200μg;(3)Inactivated bacteria lacking the K39 protein;(4)Non-immunized control animals.Serological monitoring was performed.All groups were challenged by intraperitoneal injection of 10^(7) Leishmania infantum promastigotes.After euthanasia,the liver and spleen were collected to analyze the levels of TNF,IFN-γ,IL-12,IL-4,and IL-10.Results:Mice immunized with purified rK39 or the inactivated bacterial vector carrying the K39 antigen of Leishmania infantum showed a long-lasting immune response with high levels of polyclonal antibodies specifically recognizing the recombinant proteins.The IgG1 subclass was the predominant immunoglobulin;however,the induction of IgG2a and the profile of cytokines produced were indicative of the induction of a mixed-type response.Conclusions:The inactivated bacterial vector carrying the K39 antigen,as well as the purified antigen can induce a long-lasting immune response in immunized mice,predominantly favouring a Th2 profile response.

Th1 cells inducing IFNγ response improves immunotherapy efficacy in gastric cancer

Objective: Cancer immunotherapy has made remarkable advances in recent years, but its effectiveness in treating gastric cancer is often limited by the complexity of the tumor microenvironment and the lack of effective biomarkers. This study aimed to identify effective biomarkers for immunotherapy treatment by characterizing the tumor microenvironment.Methods: We retrieved the RNA-seq data from gastric cancer patients treated with the programmed death 1(PD-1) blockade pembrolizumab. Differentially expressed genes associated with clinical outcomes were identified and further analyzed using gene ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis. Gene signature scores were calculated by single sample Gene Set Enrichment Analysis(ssGSEA). The infiltration levels of immune cells were quantified using the xCell website. Cell type enrichment analysis was performed to compare treatment response and non-response groups, and regression analysis was used to investigate the relationship between interferon gamma(IFNγ) immune response and immune cell infiltration. Biomarkers were identified using least absolute shrinkage and selection operator(LASSO) analysis.Results: Compared to normal tissues, cytokine activity and interleukin-6 production were highly activated in gastric tumors. Responders to pembrolizumab showed significantly up-regulated expression of IFNγ responserelated genes. Cell type enrichment analysis revealed that Th1 cells were significantly enriched in the tumor microenvironment of responders. Regression analysis indicated that Th1 cells induced IFNγ response more efficiently than other cell types. Using signatures of Th1 cells, stromal cells and IFNγ response, a set of eight genes were identified that effectively predicted the efficacy of immunotherapy treatment and patient prognosis.Conclusions: Th1 cells promote therapeutic efficacy of PD-1 blockade by promoting IFNγ immune response in gastric cancer. The identified biomarkers have the potential to improve the effectiveness of immunotherapy treatment for gastric cancer patients.

Analysis of Specific Th1/Th2 Helper Cell Responses and IgG Subtype Antibodies in Anti-CD4 Monoclonal Antibody Treated Mice with Autoimmune Cardiomyopathy

The cytokine repertoire of ADP/ATP carrier-specific humoral immune responses and the cytokine-dependent anti-ADP/ATP carrier antibody IgG subclasses were examined in a cohort of ADP/ATP carrier-immunized BALB/c mice treated with anti-CD4 monoclonal antibody. Eighteen male BALB/c mice （6–8 weeks old） were randomized into 3 groups： dilated cardiomyopathy （DCM） group, DCM-tolerance （Tol） group and control group. The mice in DCM group were immunized with the peptides derived from human ADP/ATP carrier protein for 6 months and mice in the control group were sham-immunized, while the mice in DCM-Tol group were immunized with ADP/ATP carrier protein and anti-CD4 McAb simultaneously. Serum autoantibody against ADP/ATP carrier and IgG subclasses were measured by ELISA, intracellular cytokines IFN-γ and IL-4 of Th cells were moni- tored with flow cytometry, and splenic T cell cytokines IFN-γ, IL-2, IL-4 and IL-6 were detected by using real-time fluorescent quantitative PCR. The results showed that the autoantibody against ADP/ATP carrier was found in all mice in DCM group, and the antibody level, serum IgG1 and IgG2a subclasses, cytokines in T cells and Th cells were all elevated in DCM group, as compared with those in control group （P〈0.01）. On the other hand, in DCM-Tol group, the autoantibody level and contents of all the cytokines were significantly different from those in DCM group （P〈0.01）, and were close to those in control group. And the levels of IgG1, IgG2a, IgG2b and IgG3 were influenced, to varying degrees, by anti-CD4 McAb as compared with those in DCM group. All these four types of IgG subclasses were substantially decreased in DCM-Tol group as compared with DCM group. It is concluded that the treatment with anti-CD4 McAb could prevent the activation of T cells, reverse the abnormal secretion of cytokines and the imbalance between Th1/Th2 cell subsets and abnormal production of autoantibody against ADP/ATP carrier, and eventually avoid myocardial injuries.

Correlation of serum nutrient levels with immune cell differentiation and inflammatory response activation in children with pneumonia

Objective:To investigate the correlation of serum nutrient levels with immune cell differentiation and inflammatory response activation in children with pneumonia.Methods:200 children with pneumonia who were treated in our hospital between April 2015 and August 2017 were selected as the pneumonia group, and 100 healthy children who were vaccinated in this hospital during the same period were selected as the normal control group. The differences in serum levels of nutrients, Th1/Th2 cytokines, Th17/Treg cytokines and inflammatory mediators were compared between the two groups. Pearson test was used to assess the relationship between serum nutrient levels and disease severity.Results: Serum Vit A, Fe and Zn levels of pneumonia group were lower than those of control group. The differences in serum Vit D, Ca and Mg levels were not statistically significant between the two groups of children. Serum Th1 cytokines IL-2 and TNF-β contents of pneumonia group were lower than those of control group whereas Th2 cytokines IL-4 and IL-5 contents were higher than those of control group;Th17 cytokines IL-17, IL-21 and IL-22 contents were higher than those of control group whereas Treg cytokines IL-10 and TGF-β contents were lower than those of control group;inflammatory mediators CRP, PCT and MCP-1 contents were significantly higher than those of control group. Pearson test showed that serum nutrients Vit A, Fe and Zn levels in children with pneumonia were directly correlated with the degree of immune cell differentiation and inflammatory response.Conclusion: Serum Vit A, Fe, Zn and other nutrient levels abnormally decrease in children with pneumonia, and the specific level are directly correlated with the severity of the disease.

Duchesnea Phenolic Fraction Inhibits Tumor Growth through Restoring the Th1/Th2 Balance in U14 Cervical Cancer Bearing Mice

Duchesnea indica (Andr.) Focke has been traditionally used to treat cancer in Asian countries for centuries. In the present study, transplanted U14 cervical cancer mouse model was used to evaluate the antitumor and immunomodulatory activity of Duchesnea phenolic fraction (DPF). ELISA and RIA assay were employed to measured the serum concentration of Th1/Th2 cytokines (IL-2, IL-4, IFN-γ and TNF-α). Administration with 0.25 g/kg, 0.5 g/kg and 1 g/kg DPF significantly reduced the tumor weight by 34.37%, 43.89% and 56.28%, respectively, as compared to the tumor control group. Furthermore, the serum level of IL-2, IFN-γ and TNF-α increased and IL-4 level decreased in a dose-dependent manner during DPF treatment, indicating that the antitumor activity of DPF may be associated with the decrease of TNF-α level and restoration of the balance of Th1/Th2 cell responses. These data suggested that DPF, a mixture of plant polyphenols, had potent anticancer activity which was in part accomplished by its immunomodulatory ability.

Inactivated Pseudomonas PE(△Ⅲ)exotoxin fused to neutralizing epitopes of PEDV S proteins produces a specific immune response in mice

Porcine epidemic diarrhea(PED)caused by the porcine epidemic diarrhea virus(PEDV),is a severe infectious and devastating swine disease that leads to serious economic losses in the swine industry worldwide.An increased number of PED cases caused by variant PEDV have been reported in many countries since 2010.S protein is the main immunogenic protein containing some B-cell epitopes that can induce neutralizing antibodies of PEDV.In this study,the construction,expression and purification of Pseudomonas aeruginosa exotoxin A(PE)without domain Ⅲ(PE△Ⅲ)as a vector was performed for the delivery of PEDV S-A or S-B.PE(△Ⅲ)PEDV S-A and PE(△Ⅲ)PEDV S-B recombinant proteins were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analysis.The immunogenicity of PEDV S-A and PEDV S-B subunit vaccines were evaluated in mice.The results showed that PEDV-S-B vaccine could not only induce specific humoral and Th1 type-dominant cellular immune responses,but also stimulate PEDV-specific mucosal immune responses in mice.PEDV-S-B subunit vaccine is a novel candidate mucosal vaccine against PEDV infection.

T-bet, GATA-3 and Foxm1 expression in chronic sinusitis mucosa and their correlation with inflammatory molecule expression

Objective: To study the T-bet, GATA-3 and Foxm1 expression in chronic sinusitis mucosa and their correlation with inflammatory molecule expression. Methods: Patients with sinusitis and deflection of nasal septum who received nasal endoscopic surgery in Shengli hospital between June 2015 and February 2017 were selected and enrolled in CRS group and control group respectively. The nasal mucosa tissue was collected during operation to determine the mRNA expression of T-bet, GATA-3 and Foxm1 as well as the protein expression of inflammatory molecules. Results: T-bet, GATA-3 and Foxm1 mRNA expression as well as IL-1β, IFN-γ, TNF-α, IL-4, IL-5, IL-19, IL-20R1, IL-20R2, MMP2, MMP9, PI3K, Akt, GSK-3β and p38MAPK protein expression in nasal mucosa tissue of CRS group were significantly higher than those of control group;T-bet, GATA-3 and Foxm1 mRNA expression in nasal mucosa tissue of patients with CRS were positively correlated with IL-1β, IFN-γ, TNF-α, IL-4, IL-5, IL-19, IL-20R1, IL-20R2, MMP2, MMP9, PI3K, Akt, GSK-3β and p38MAPK protein expression. Conclusions: The high expression of T-bet, GATA-3 and Foxm1 in chronic sinusitis mucosa tissue can activate Th1 and Th2 immune response and cause mucosal inflammatory response.

Helicobacter pylori infection:How does age influence the inflammatory pattern?

The inflammatory pattern during Helicobacter pylori(H.pylori)infection is changeable and complex.During childhood,it is possible to observe a predominantly regulatory response,evidenced by high concentrations of key cytokines for the maintenance of Treg responses such as TGF-β1 and IL-10,in addition to high expression of the transcription factor FOXP3.On the other hand,there is a predominance of cytokines associated with the Th1 and Th17 responses among H.pylori-positive adults.In the last few years,the participation of the Th17 response in the gastric inflammation against H.pylori infection has been highlighted due to the high levels of TGF-β1 and IL-17 found in this infectious scenario,and growing evidence has supported a close relationship between this immune response profile and unfavorable outcomes related to the infection.Moreover,this cytokine profile might play a pivotal role in the effectiveness of anti-H.pylori vaccines.It is evident that age is one of the main factors influencing the gastric inflammatory pattern during the infection with H.pylori,and understanding the immune response against the bacterium can assist in the development of alternative prophylactic and therapeutic strategies against the infection as well as in the comprehension of the pathogenesis of the outcomes related to that microorganism.

Type 1 T-cell responses in chlamydial lung infections are associated with local MIP-1a response

Chemokines and their receptors are important mediators of leukocyte trafficking and recruitment and sometimes work as modulators of T-cell responses during infections and inflammation.Modulating the biological activity of chemokines has been found to influence the course of diseases.However,little is known about the role of chemokine responses during chlamydial lung infections.We therefore analyzed the dynamics of multiple chemokines,which are frequently associated with type 1(Th1)T cell immune responses,and their receptors for their expression in the lungs during Chlamydia muridarum(Cm)infections.We also examined the relationship between chemokine responses and the development of Th1 responses as well as the clearance of infection.Our results showed that in parallel with the high levels of gamma interferon(IFN-c)and IL-12 production in the lungs and draining lymph nodes,and the expansion of IFN-c-producing CD4 and CD81 T cells,the production of the cell-related chemokines RANTES,IFN-c-inducible protein-10(IP-10)and macrophage inflammatory protein-1a(MIP-1a)and their receptor CCR1 was elevated in the lung tissues after infection.Interestingly,in a later phase of infection,the expression of RANTES and IP-10 remained elevated but the expression of MIP-1a and CCR1 decreased to a low level,which suggests a closer association with the pattern of Th1 cytokine responses in the process of infection.These results suggest a close association between the MIP-1a response and the Th1-type T-cell responses in chlamydial lung infections .

Th1/Th2 type cytokines in hepatitis B patients treated with interferon-α

Objective To investigate the relationship between the expression of Th1/Th2 type cytokines and the effect of interferon-α therapy. Methods Th1/Th2 type cytokines were assayed by enzyme-linked immunosorbent assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR) on 23 patients with chronic hepatitis B who were treated with interferon-α.Results Levels of IFN-γ in the supernatant of peripheral blood mononuclear cells (PBMC) cultures from the patients with hepatitis B were slightly lower than those of controls (P=0.07). However, the levels of IL-4 were higher than those of controls (P=0.01). Cytokines measurements during IFN-α treatment showed a trend to decreaseing levels of IL-4 at 4, 12, and 24 weeks. Levels of IFN-γ were slightly increased following IFN-α treatment (P=0.09). In patients with a complete response to IFN-α, the levels of IFN-γ were higher at 24 weeks following IFN-α treatment than that of pre-treatment (P=0.04), and the levels of IL-4 decreased markedly at 12 and 24 weeks (P=0.02, 0.03, respectively). mRNA expression positively correlated with the level of Th1/Th2 type cytokines in the supernatant. Conclusion The expression of Th2 type cytokines is predominant in patients with chronic hepatitis B. Interferon-α therapy can modulate the balance of Th1/Th2 type cytokines, and this is related to its clinical effect. Levels of Th1/Th2 type cytokines could be a predictor of clinical response during Interferon -α treatment.

The Dual Effects of Interleukin-18 in Tumor Progression

Interleukin-18 （IL-18） was discovered as an interferon-y-inducing factor and had a critical role in inflammatory and immune respouse. It stimulates natural killer （NK） and T cells and enhances Thl immune response. These activated immune cells eliminate cancer cells and virus-infected cells effectively. However, IL-18 has also been found to promote tumor progression. Higher expression or secretion level of IL-18 is detected in various cancer cells in comparison with normal control, and IL-18 is able to induce angiogenesis, migration/metastasis, proliferation and immune escape. These dual effects and the mechanism of IL-18 need to be investigated further as it relates to cancer.

Immunization with chlamydial plasmid protein pORF5 DNA vaccine induces protective immunity against genital chlamydial infection in mice

To validate the immune protective efficacy of pORF5 DNA vaccine and to analyze potential mechanisms related to this protection. In this study, pORF5 DNA vaccine was constructed and evaluated for its protective immunity in a mouse model of genital chlamydial infection. Groups of BALB/c mice were immunized intranasally with pORF5 DNA vaccine. Humoral and cell mediated immune responses were evaluated. The clearance ability of chlamydial challenge from the genital tract and the chlamy- dia-induced upper genital tract gross pathology and histopathological characterization were also de- tected. The results showed that the total and the IgG2a anti-pORF5 antibody levels in serum were sig- nificantly elevated after pcDNA3.1-pORF5 vaccination, as were the total antibody and IgA levels in vaginal fluids. pcDNA3.1-pORF5 induced a significantly high level of Th1 response as measured by robust gamma interferon (IFN-γ). Minimal IL-4 was produced by immune T cells in response to the re-stimulation with pORF5 protein or the inactive elementary body in vitro. pcDNA3.1-pORF5-vacci- nated mice displayed significantly reduced bacterial shedding upon a chlamydial challenge and an accelerated resolution of infection. 100% of pcDNA3.1-pORF5 vaccinated mice successfully resolved the infection by day 24. pcDNA3.1-pORF5-immunized mice also exhibited protection against patho- logical consequences of chlamydial infection. The stimulated index was significantly higher than that of mice immunized with pcDNA3.1 and PBS (P<0.05). Together, these results demonstrated that immu- nization with pORF5 DNA vaccine is a promising approach for eliciting a protective immunity against a genital chlamydial challenge.