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Several approaches have so far been employed to establish anti-tumor immunity by targeting HER2 protein. Active immunization with recombinant HER2 subdomains has previously been demonstrated to induce potent immune response and tumor growth inhibition. In the present study, we investigated the immunogenicity and tumor inhibitory effect of a fusion protein consisting of human HER2 extracellular subdomain (ECD-DI + II) together with T-helper cell epitopes of Tetanus toxin (p2 and p30).BALB/c mice were immunized with two recombinant proteins (DI + II and p2p30-DI + II) emulsified in 4 different adjuvants. Anti-DI + II antibody response, cytokine profile, frequency of splenic CD25Both recombinant proteins were able to induce comparable levels of ECD-DI + II-specific antibodies. Immunization with p2p30-DI + II resulted in a significant increase in the level of Interferon-gamma (IFN-γ) secretion compared to DI + II protein and significantly higher frequency of CTLs and lower frequency of Tregs. The number of mice that remained tumor-free until day 120 was significantly higher in p2p30-DI + II vaccinated groups.Our data suggest that the p2p30-DI + II fusion protein together with CpG adjuvant induces more potent anti-tumor immune responses in a mouse tumor model. Accordingly, this formulation might be considered as a potential immunotherapeutic approach in HER2

Objective Human epidermal growth factor receptor 3 (HER3) is a unique member of the tyrosine kinase receptors with an inactive kinase domain and is the preferable dimerization partner for HER2 which lead to potent tumorigenic signaling. Methods In this study, the expression plasmids coding for the human HER3 subdomains were transfected into CHO-K1 cells. Produced proteins were characterized by ELISA and SDS-PAGE. Rabbits were immunized and produced polyclonal antibodies (pAbs) that were characterized by ELISA, Immunoblotting and flowcytometry and their inhibitory effects were assessed by XTT on BT-474 and JIMT-1 breast cancer cell lines. Result The recombinant subdomains were highly immunogenic in rabbits. The pAbs reacted with the recombinant subdomains as well as commercial HER3 and the native receptor on tumor cell membranes and could significantly inhibit growth of Trastuzumab sensitive (BT-474) and resistant (JIMT-1) breast cancer cell lines in vitro. Conclusion It seems that HER3 extra cellular domains (ECD) induce a strong anti-tumor antibody response and may prove to be potentially useful for immunotherapeutic applications. .

Background: Human polyclonal plasma-derived hepatitis B immunoglobulin (HBIG) is currently used for immunoprophylaxis of HBV infection. The development of virus-neutralizing monoclonal antibodies (MAbs) requires the use of optimized cell culture systems supporting HBV infection. Objective: This study aims to optimize the hepatitis B virus infectivity of NTCP-reconstituted HepG2 (HepG2-NTCP) cells to establish an efficient system to evaluate the HBV-neutralizing effect of anti-HBs MAbs. Methods: Serum-derived HBV (sHBV) and cell culture-derived HBV (ccHBV) were simultaneously used for the optimization of HBV infection in HepG2-NTCP cells by applying different modifications. Results: Our results for the first time showed that in addition to human serum, monkey serum could significantly improve ccHBV infection, while fetal and adult bovine serum as well as duck and sheep serum did not have a promotive effect. In addition, sHBV and ccHBV infectivity are largely similar except that adding 5% of PEG, which is commonly used to improve in vitro infection of ccHBV, significantly reduced sHBV infection. We showed that a combination of spinoculation, trypsinization, and also adding human or monkey serum to HBV inoculum could significantly improve the permissivity of HepG2-NTCP cells to HBV infection compared with individual strategies. All anti-HBs MAbs were able to successfully neutralize both ccHBV and sHBV infection in our optimized in vitro system. Conclusion: Our study suggests different strategies for improving ccHBV and sHBV infection in HepG2-NTCP cells. This cell culture-based system allows assessment of HBV neutralizing MAbs and may also prove to be valuable for the analysis of other HBV neutralizing therapeutics.

The receptor tyrosine kinase-like orphan receptor 1 (ROR1) is a new tumor associated antigen (TAA) which is overexpressed in several hematopoietic and solid malignancies. The present study aimed to produce and evaluate different fusion proteins of mouse ROR1 (mROR1) to enhance immunogenicity and protective efficacy of ROR1. Four ROR1 fusion proteins composed of extracellular region of mROR1, immunogenic fragments of TT as well as Fc region of mouse IgG2a were produced and employed to immunize Balb/C mice. Humoral and cellular immune responses and anti-tumor effects of these fusion proteins were evaluated using two different syngeneic murine ROR1+ tumor models. ROR1-specific antibodies were induced in all groups of mice. The levels of IFN-γ, IL-17 and IL-22 cytokines in culture supernatants of stimulated splenocytes were increased in all groups of immunized mice, particularly mice immunized with TT-mROR1-Fc fusion proteins. The frequency of ROR1-specific CTLs was higher in mice immunized with TT-mROR1-Fc fusion proteins. Finally, results of tumor challenge in immunized mice showed that immunization with TT-mROR1-Fc fusion proteins completely inhibited ROR1+ tumor cells growth in two different syngeneic tumor models until day 120 post tumor challenge. Our preclinical findings, for the first time, showed that our fusion proteins could be considered as a potential candidate vaccine for active immunotherapy of ROR1-expressing malignancies.

Two categories of regulatory T cells (Tregs), nTreg and iTreg, play vital roles in orchestrating the integrity of a host in the course of an immune response. Tregs commonly belong to CD4+ CD25+ T cells and they are characterized by a transcription factor - forkhead box P3 (FoxP3). Within the space of the last few years, interests have been drawn to Tregs as a therapeutic tool in several settings like autoimmune disease, transplantation, and tumor disorders. As a consequence, to assess the functional properties of Tregs, namely through their ability to suppress other cells, cytokine expression, and proliferation in a variety of conditions, it is mandatory to gain better approaches to this end. This would be beneficial in designing better-than-ever therapeutic methods with regard to Tregs properties. Gaining better insights into the underlying mechanisms of immune regulation, by means of straightforward and less time-consuming techniques, will hopefully permit the therapeutic application of these cells in the control of human disorders. This review aims at going through the basic methods for Treg isolation as well the efficiency of the commonly exerted in vitro assays of Tregs-mediated immune suppression.

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by autoreactive antibodies. Recent findings revealed the importance of innate immune responses, especially Toll-like receptors (TLRs) in the pathogenesis of SLE.In this study, the level of TLR9 expression on peripheral blood mononuclear cells (PBMCs) was analyzed. The levels of produced IFN-α were also measured in supernatant of PBMCs from SLE patients and healthy controls after stimulation with CpG ODN2216 which is a plasmocytoid dendritic cell (pDC)-specific TLR9 ligand.TLR9 expression was analyzed by real-time polymerase chain reaction (PCR) and flow cytometry in 35 SLE patients and 38 healthy controls and IFN-α concentration was measured in supernatants using enzyme-linked immunosorbent assay (ELISA).The results showed that the TLR9 expression in the mRNA and the protein level was significantly higher in PBMCs from SLE patients. However, IFN-α concentration in patients and controls significantly increased in response to CpG stimulation but this increase was significantly higher in healthy controls compared with SLE patients. Our results do not show any association between taking hydroxychloroquine and reduction in IFN-α production in SLE patients.Regarding the findings of the study, there is the possibility that TLR9 has played a role in SLE pathogenesis, and consequently it implies that TLRs can be considered to be the therapeutic targets for systemic autoimmunity. We may conclude that PBMCs in patients are functionally impaired in response to TLR ligation via innate response stimulating pathogen-associated molecular patterns (PAMPs).

An appropriate differentiation of distinct human CD4+ T cell subset is critical for manipulating these cells for using in immunity related diseases. Despite various attempts to clarify the role of different factors involved in Th17 differentiation, many crucial contradictions yet remained to be optimized. Although it has been shown that the differentiation of in-vitro Th17 cells culture conditions requires the presence of IL-1beta, IL-23, IL-2, IL-21, IL-6 and TGF-β, the optimum amount of TGF-β regulating in vitro human Th17 cell differentiation is still unclear. In the current study, a flow cytometric assay was used to evaluate the effect of different concentrations of TGF-β and a combination of IL-1beta, IL-23, IL-2 without using IL-6 on development of Interleukin (IL)-17-producing T helper (Th17) cells. According to our findings, 0.1 ng/ml of TGF-β significantly increases the expression of IL-17 in comparison to other concentrations of this cytokine. Results indicated the vital role of TGF-β cytokine in the polarization of human Th17 cells in vitro.

An appropriate differentiation of distinct human CD4+ T cell subset is critical for manipulating these cells for using in immunity related diseases. Despite various attempts to clarify the role of different factors involved in Th17 differentiation, many crucial contradictions yet remained to be optimized. Although it has been shown that the differentiation of in-vitro Th17 cells culture conditions requires the presence of IL-1beta, IL-23, IL-2, IL-21, IL-6 and TGF-β, the optimum amount of TGF-β regulating in vitro human Th17 cell differentiation is still unclear. In the current study, a flow cytometric assay was used to evaluate the effect of different concentrations of TGF-β and a combination of IL-1beta, IL-23, IL-2 without using IL-6 on development of Interleukin (IL)-17–producing T helper (Th17) cells. According to our findings, 0.1 ng/ml of TGF-β significantly increases the expression of IL-17 in comparison to other concentrations of this cytokine. Results indicated the vital role of TGF-β cytokine in the polarization of human Th17 cells in vitro.

Autoimmunity shows a concerning growth recently. It seems that role of diet is important for development of autoimmunity. Nutritional elements can affect immune system functions. Oversupply or deficiency of specific metabolites may change performance of immune cells, especially that of T helper lymphocytes. For example, glucose, omega 3 and poly unsaturated fatty acids can induce specific Th subsets which play a critical role in autoimmune diseases. T lymphocytes, mostly T CD4+ (Th cells) not only play a critical role in orchestrating immune responses, but also they have major role in pathogenesis of some autoimmune disease. Hence, we designed a research to find out effects of oleic and palmitic acids on differentiation of Th cells. We added oleic acid, palmitic acids and combination of them on peripheral blood mononuclear cells (PBMC) culture and cells were harvested for RT-PCR and flow cytometry analysis after seven days. Our results showed that palmitic and oleic acids induce Th1 and Th17 subsets (p-valu

To investigate the associations of hepatitis B virus (HBV) genotype with HBeAg and anti-HBe status, alanine aminotransferase (ALT) levels and HBV-DNA detection in different groups of HBV-infected patients in southwest Iran.A total of 89 HBsAg-positive serum samples were collected from the same number of patients. All sera were then investigated to determine HBV DNA and serological markers. For all the polymerase chain reaction (PCR)-positive samples, biochemical, histopathological assays and genotyping were also performed.Genotype D was the only type of HBV found in different clinical forms of acute and chronic infections. There was a high prevalence of HBeAg-negative HBV-infected patients with chronic hepatitis (52.7%). Out of 55 patients with chronic hepatitis, seven (12.7%) were diagnosed with cirrhosis. A significant association between the presence of anti-HBe antibody and an increase in ALT level, among either HBeAg-negative (P = 0.01) or HBeAg-positive (P = 0.026) patients, was demonstrated. No significant differences were observed between the clinical outcomes of HBeAg-positive and -negative individuals (P = 0.24).Genotype D has been recognized as the only type of HBV found in different clinical forms of HBV infections, including cirrhosis, among the residents of southwest Iran. Anti-HBe possibly plays a role in disease progression in some patients with chronic hepatitis, at least for a period of disease.