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Aim: Increased IgE levels have made house dust mite allergens one of the most frequent causes of allergies worldwide. Treatment reduces the IgE antibodies and types two cytokines, namely interleukin‐4 (IL‐4) and IL‐13. Although existing treatments significantly reduce IgE or IL‐4/IL‐13, they are very costly. This study aimed to construct a recombinant protein derived from rDer p1 peptides in the form of an immunotherapy approach and to measure the response of IgE and IgG antibodies. Methods: The proteins were isolated, purified, and evaluated using the SDS‐PAGE and Bradford test and confirmed by using Western blot. To evaluate immunotherapy efficiency, 24 BALB/C mice were sensitized intraperitoneally with house dust mites (HDM) adsorbed to Aluminum hydroxide (Alum) and randomly divided into four groups of six: control sensitized, HDM extract, rDer p1, and DpTTDp vaccine. To immunization, four groups of random mice were each treated with phosphate‐buffered saline, 100 μg of rDer p1 protein, DpTTDp, or HDM extract, every 3 days. Direct ELISA determined HDM‐specific IgG and IgE subclasses. Data were analyzed in SPSS and Graph pad prism software. Values of p <.05 were considered significant. Results: After immunization of mice, the rDer P1 and recombinant vaccine like HDM extract increased IgG antibody titer and decreased IgE‐dependent reactivity in allergic mice to rDer P1. Also, the levels of inflammatory IL‐4 and IL‐13 cytokines as allergic stimulants decreased. Conclusion: The use of present available recombinant proteins is considered a viable, cost‐effective, and long‐term option for providing effective HDM allergy immunotherapy vaccines without side effects. [ABSTRACT FROM AUTHOR]

Selective deficiency of immunoglobulin A (IgA) is the most frequent primary hypogammaglobulinemia. As some IgA-deficient patients have IgA antibodies in their plasma which may cause anaphylactic reactions, blood centers usually maintain a list of IgA-deficient blood donors to prepare compatible blood components. In this study we determined the incidence of selective IgA deficiency (SIgAD) in normal adult Iranian population. 13022 normal Iranian blood donors were included in this study. The assay which we used was adapted to the manual pipetting system and ELISA reader was used for screening. Other classes of immunoglobulins (G, M), as well as secretory IgA and IgG subclasses were tested in IgA deficient cases by ELISA. SPSS was used for statistical analysis. Among 13022 studied cases, 11608 blood donors were males (89.14%) and 1414 were females (10.86%). Their mean (±SD) age and weight were 38.5±11 years and 82±12 Kg respectively. Twenty of the screened samples were found by means of ELISA to be IgA-deficient (less than 5mg/dl), (frequency; 1:651). The data could indicate a compensation for IgA deficiency by serum IgM in one of our IgA deficient cases (Patient 5). We observed a correlation between IgG3 and serum IgA in deficient cases (r=0.498, P=0.025). Our results indicate that in present study the prevalence of S IgA D is in agreement with data from other Caucasians populations (from 1:300 to 1:700). In conclusion, Selective IgA Deficiency could be almost asymptomatic in most cases in general population. Our study suggests that; due to high frequency of IgA deficiency in Iran, it seems necessary to measure IgA levels for every blood donor and blood recipient to find IgA deficient cases.

Objective(s): Blocking of vascular endothelial growth factor (VEGF) plays a pivotal role in inhibition of metastasis and is a target for development of anti-angiogenic agents. In this study, a peptide-based vaccine was designed and its potential for induction of humoral immune responses, generation of neutralizing antibodies, inhibition of tumor growth and metastasis was determined. Materials and Methods: With online bioinformatics tools, a fragment of the VEGF-A was selected for a peptide-based vaccine. To enhance its antigenicity, the peptide was conjugated with Keyhole limpet hemocyanin and used to immunize mice. Then, the polyclonal anti-VEGF antibody titer was measured and its effect on proliferation of HUVEC cell line was investigated by MTT assay. Finally, we checked the effect of the peptide on tumor growth, metastasis, and survival rates in a mouse model of cancer. Results: The bioinformatics analysis of the selected region confirmed dis-similarity of the peptide with any other human protein and its acceptable antigenicity to stimulate a tumor-specific humoral response. Anti-VEGF antibody titers were significantly greater in vaccinated mice than in controls. IgG antibody from mice immunized with recombinant VEGF-A inhibited HUVEC proliferation (P<0.0001). Tumors in vaccinated mice were significantly smaller than those in controls. Moreover, metastasis was reduced and survival rates increased in the vaccinated group. Conclusion: Production of high-titer antibody against the peptide vaccine indicated that the peptide has the potency to be used as a peptide-based vaccine for humoral inhibition of tumor growth and metastasis. The efficacy of the peptide should be further tested in primate models. [ABSTRACT FROM AUTHOR]

Interferonbeta-1b (IFNβ-1b) developed as therapeutic protein for the treatment of multiple sclerosis (MS). Studies have been shown that Long-term usage of this protein can lead to the development of anti-drug antibodies (ADAs) and this phenomenon cause total loss or reduced efficacy of IFNβ-1b. The aim of this study was to predict and silence IFNβ-1b T-cells epitopes by in silico methods and genetic engineering. Based on bioinformatics studies we identified optimal sets of conservative point mutations for eliminating T-cells epitopes in IFNβ-1b protein. Four synthetic genes with desirable mutation constructed and PET26b+ was used as an expression vector in E. coli. The expression of this proteins confirmed by SDS-PAGE and Western blotting, consequently, IFNβ-1b proteins was purified by His-tag chromatography. To determined activity of mutants' variants anti-proliferative and anti-viral activity compared to wild form was evaluated using MTT assay in A549 and Vero cells lines respectively. Also the immunogenicity of mutant proteins compared with Betaseron measured in BALB/c mice. The in vitro bioactivity analysis demonstrated that functional activities of all mutant proteins were maintained and is the same as biological activity of Betaseron. Pharmacokinetic studies suggest that, in engineered proteins that contain substitution of Histidine to Glutamic Acid at position 131 (mut 2 and mut 1+2) antibodies response reduced by about 50%, as compared to that for Betaseron. Computational analysis expedites identification and prediction of epitopes in therapeutic protein, therefore, we used immunoinformatic tools for modification of dominant T-cell epitope in IFNβ-1b protein, and this strategy has capacity to create proteins which have naturally reduced immunogenicity. [ABSTRACT FROM AUTHOR]

In this research, we investigated the phytochemical profiles for two models of aqueous (Aq) and methanolic (Me) pollen extracts of F. excelsior from three pollination periods from hermaphrodite flowers (H) of polygamous and male flowers of pure male (M) in order to identify their constituent compounds. Pollens of both phenotypes H and M were collected during three pollination periods and were analyzed by light and scanning electron microscopy (LM/ SEM). The total phenolic content (TPC) and flavonoids content (TFC) was measured using Folin-Ciocalteu and aluminum chloride (AlCl3) methods, respectively. Antioxidant activities were evaluated using ferric reducing antioxidant power (FRAP) and scavenging free radical DPPH• and ABTS•+. GC-FID and GC/MS were used to identify the chemical composition of essential oils. There was a significant difference (P < 0.001) between the means of TPC for M and TFC for the H. Comparison of H and M antioxidant activities showed that DPPH (IC50) to be (2.977 ± 0.117 μM) during the second pollination period of M and (4.877 ± 0.021 μM) for first period of H. The majority of the compounds identified were linalool (35.42%) from the monoterpenoides in H and Delta-cadinene (43.22%) belonging to the sesquiterpenes in M. We concluded that there is a significant difference between the H and M compounds in pollen at different periods. [ABSTRACT FROM AUTHOR]

Current therapeutic approaches in allergic diseases especially asthma generally focus on using immunological strategies. According to the importance of FceRI in controlling allergic response we used two extracellular regions of Fc epsilon receptor I (FceRI) beta subunit peptides to design two peptide-based vaccines. Probably these peptides vaccines by triggering the immune response to FceRI can reduce the allergic symptoms through blocking the IgE specific receptor. Two extracellular parts of FceRI beta subunit were made by peptide synthesizer and conjugated with keyhole limpet Hemocyanin. These conjugated peptides were used and evaluated as therapeutic vaccines in allergic airway inflammation mouse model. Total IgE and anti ovalbumin specific IgE were measured in mice serum and compared in vaccinated and unvaccinated allergic mice. Histamine, prostaglandin D2 (PGD2), IL-4 and IL-13 were measured in bronchoalveolar lavage (BAL) fluid of vaccinated allergic mice versus unvaccinated and histopathologic examination were performed in studied groups. After vaccination of mice with each of the peptide vaccines the specific antibodies titer increased significantly in vaccinated groups versus unvaccinated. In histopathologic study, lavage eosinophil percentage and peribronchial inflammation in lung sections of vaccinated groups was decreased (p<0.05). Also the allergic components including total IgE, anti ovalbumin specific IgE, histamine, PGD2, IL-4, and IL-13 showed substantial decline in vaccinated allergic mice.  Thus targeting the extracellular regions of FceRI beta subunit by peptide-based vaccines and induction of specific antibodies against them can reduce allergic responses in allergic mice model. [ABSTRACT FROM AUTHOR]