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A simple one-step method for the purification of recombinant His-tagged profilin from the bacterial cell lysate is reported. Noting the greater ease with which hexahistidine-tagged proteins can be metalprecipitated compared with unwanted protein impurities, we investigated the effect of lysis-buffer additives and optimization of other conditions to recover selectively desired proteins in a one-step metal precipitation without using biopolymers. Purification of the His-tagged melon (Cucumis melo) profilin was used to demonstrate the utility of this method and up to 80% recovery with a purity of 98% was achieved. This method obtained a yield of the protein nearly comparable with that obtained using metal-affinity chromatography. This purification procedure can reduce the time and cost of the purification process, especially on a large scale. [ABSTRACT FROM AUTHOR]

Background. Psoriasis is a noncontagious auto‐inflammatory chronic skin disease. So far, some of the inflammatory genes were upregulated in mouse model of psoriasis. This study examined changes in skin mRNA expression of L‐kynureninase (Kynu), cathelicidin antimicrobial peptide (Camp), beta‐defensin 2 (Defb2), and proenkephalin (Penk) in a mouse model of imiquimod‐induced psoriasis. Materials and Methods. Tree groups of C57BL/6 female mice were allocated. The imiquimod (IMQ) cream was administered to the mice dorsal skin of the two groups to induce psoriatic inflammation. In the treatment group, IMQ was administered 10 min after hydrogel‐containing M7 anti‐IL‐17A aptamer treatment. Vaseline (Vas) was administered to the negative control group. The psoriatic skin lesions were evaluated based on the psoriasis area severity index (PASI) score, histopathology, and mRNA expression levels of Kynu, Camp, Defb2, and Penk using real‐time PCR. In order to assess the systemic response, the spleen and lymph node indexes were also evaluated. Results. The PASI and epidermal thickness scores were 6.01 and 1.96, respectively, in the IMQ group, and they significantly decreased after aptamer administration to 1.15 and 0.90, respectively (P < 0.05). Spleen and lymph node indexes showed an increase in the IMQ group, followed by a slight decrease after aptamer treatment (P > 0.05). Additionally, the mRNA expression levels of Kynu, Defb2, Camp, and Penk genes in the IMQ‐treated region showed a significant 2.70, 4.56, 3.29, and 2.61‐fold increase relative to the Vas mice, respectively (P < 0.05). The aptamer‐treated region exhibited a significant decrease in these gene expression levels (P < 0.05). A positive correlation was found between Kynu, Penk, and Camp expression levels and erythema, as well as Camp expression with PASI, scaling, and thickness (P < 0.05). Conclusion. According to our results, it seems that Kynu, Camp, and Penk can be considered appropriate markers for the evaluation of psoriasis in IMQ‐induced psoriasis. Also, the anti‐IL‐17 aptamer downregulated these important genes in this mouse model. [ABSTRACT FROM AUTHOR]

To increase the efficiency of aptamers to their targets, a simple and novel method has been developed based on aptamer oligomerization. To this purpose, previously anti‐human TNF‐α aptamer named T1–T4 was trimerized through a trimethyl aconitate core for neutralization of in vitro and in vivo of TNF‐α. At first, 54 mer T1–T4 aptamers with 5′‐NH2 groups were covalently coupled to three ester residues in the trimethyl aconitate. In vitro activity of novel anti‐TNF‐α aptamer and its dissociation constant (Kd) was done using the L929 cell cytotoxicity assay. In vivo anti‐TNF‐α activity of new oligomerized aptamer was assessed in a mouse model of cutaneous Shwartzman. Anchoring of three T1–T4 aptamers to trimethyl aconitate substituent results in formation of the 162 mer fragment, which was well revealed by gel electrophoresis. In vitro study indicated that the trimerization of T1–T4 aptamer significantly improved its anti‐TNF‐α activity compared to non‐modified aptamers (P < 0.0001) from 40% to 60%. The determination of Kd showed that trimerization could effectively enhance Kd of aptamer from 67 nM to 36 nM. In vivo study showed that trimer aptamer markedly reduced mean scar size from 15.2 ± 1.2 mm to 1.6 ± 0.1 mm (P < 0.0001), which prevent the formation of skin lesions. In vitro and in vivo studies indicate that trimerization of anti‐TNF‐α aptamer with a novel approach could improve the anti‐TNF‐α activity and therapeutic efficacy. According to our findings, a new anti‐TNF‐α aptamer described here could be considered an appropriate therapeutic agent in treating several inflammatory diseases. [ABSTRACT FROM AUTHOR]

Closer attention should be paid to vitamin D status in patients with mycobacterial diseases. [ABSTRACT FROM AUTHOR]

Incidence of Mycobacterium simiae pulmonary infection is increasing and diagnosis and treatment are challenging. We surveyed the clinical features, risk factors, diagnosis, and management in 20 patients from northeastern Iran diagnosed by line probe assay and confirmed by sequencing the ITS (16S‐23S) rRNA region and carried out a literature review using the keywords "pulmonary infection" and "Mycobacterium simiae." The mean age of patients was 55.1 years, with 80% female and 90% diagnosed by sputum. Clinical symptoms included severe cough (90%), sputum production (70%), haemoptysis (50%), and chest pain (35%). Comorbidities included a history of tuberculosis (60%), smoking (40%), or chronic obstructive pulmonary disease (20%). Patients were treated with levofloxacin, clarithromycin, and co‐trimoxazole. Except for two patients, the clinical symptoms improved. Mycobacterium simiae pulmonary infection is increasing in people with underlying diseases. Although choosing the most appropriate treatment remains a challenge, combining successful treatments could be useful in treating these patients. [ABSTRACT FROM AUTHOR]

Mycobacterium simiae is an emerging and spreading pathogen in Iran and little data about its drug susceptibility test (DST) and no standard treatment regimen are available. We report a case of multidrug‐resistant M. simiae respiratory infection in a 65‐year‐old woman with a history of previous Mycobacterium tuberculosis infection. The patient was treated with clarithromycin, levofloxacin, and cotrimoxazole for one year and eventually died while still suffering from respiratory problems. For DST, broth microdilution method was used according to the Clinical and Laboratory Standards Institute guidelines as well as molecular DST in clinical isolate. Mycobacterium simiae was resistant to streptomycin, moxifloxacin, clarithromycin, and cotrimoxazole antibiotics and was sensitive to clofazimine and amikacin antibiotics. Inappropriate use of antibiotics without determining the pattern of antibiotic resistance increases the likelihood of resistance and, for resistant specimens, the need to review the treatment protocol and replace antibiotics. Effectiveness based on antibiotic resistance pattern is essential. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is referred to as a "consumption" or phthisis, which has been a fatal human disease for thousands of years. Mycobacterium tuberculosis (M. tb) might have been responsible for the death of more humans than any other bacterial pathogens. Therefore, the rapid diagnosis of this bacterial infection plays a pivotal role in the timely and appropriate treatment of the patients, as well as the prevention of disease spread. More than 98% of TB cases are reported in developing countries, and due to the lack of well‐equipped and specialized diagnostic laboratories, development of effective diagnostic methods based on biosensors is essential for this bacterium. In this review, original articles published in English were retrieved from multiple databases, such as PubMed, Scopus, Google Scholar, Science Direct, and Cochrane Library during January 2010–October 2019. In addition, the reference lists of the articles were also searched. Among 109 electronically searched citations, 42 articles met the inclusion criteria. The highest potential and wide usage of biosensors for the diagnosis of M. tb and its drug resistance belonged to DNA electrochemical biosensors (isoniazid and rifampin strains). Use of biosensors is expanding for the detection of resistant strains of anti‐TB antibiotics with high sensitivity and accuracy, while the speed of these sensory methods is considered essential as well. Furthermore, the lowest limit of detection (0.9 fg/ml) from an electrochemical DNA biosensor was based on graphene‐modified iron‐oxide chitosan hybrid deposited on fluorine tin oxide for the MPT64 antigen target. According to the results, the most common methods used for M. tb detection include acid‐fast staining, cultivation, and polymerase chain reaction (PCR). Although molecular techniques (e.g., PCR and real‐time PCR) are rapid and sensitive, they require sophisticated laboratory and apparatuses, as well as skilled personnel and expertise in the commentary of the results. Biosensors are fast, valid, and cost‐efficient diagnostic method, and the improvement of their quality is of paramount importance in resource‐constrained settings. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effects of recombinant probiotic bacteria as a candidate for oral vaccine with the potential of treating allergy to Amaranthus retroflexus pollens. The main gene of this allergen, Ama r 2, was cloned into the food grade plasmid pNZ7025 and then was electrotransformed into the food grade Lactococcus lactis NZ1330. No expression was observed in the primary structure due to the distance between the ribosome binding site and the start codon. Therefore, the vector structure was corrected using the site-directed mutagenesis (SDM) technique. The cell extract of this strain was used for assessing the expression of the recombinant allergen in western blot analysis, and the existence of this protein with a molecular weight of 14.2 kDa was confirmed. To evaluate the efficacy of this strain in the treatment of allergies as an oral vaccine, probiotic ice cream was prepared. After the sensitization of mice, the treatment was performed by oral immunotherapy for 4 weeks, 4 to 5 times per week. 20 μl of functional ice cream with 1012 CFU/ml of r-L. lactis NZ1330 significantly reduced the serum IgE level. The levels of IFN-γ and TGF-β cytokines increased in the 20 μl ice cream treatment group as well as 40 μg/ml pure allergen compared with the PBS-treated group, and IL-4 cytokine levels decreased compared with the PBS-treated group. Overall, 20 μl ice cream with 1012 CFU/ml of the recombinant bacteria resulted in the best performance in terms of improving allergies to Th1 and Treg responses. [ABSTRACT FROM AUTHOR]

The human tumor necrosis factor α (hTNF‐α) is an important pro‐inflammatory cytokine which plays critical roles in inflammatory diseases such as rheumatoid arthritis (RA). The anti‐TNF‐α proteins can reduce symptoms of RA. Due to limitations of protein‐based therapies, it is necessary to find new anti‐TNF‐α agents instead of common anti‐TNF‐α proteins. Therefore, the aim of the current study was to identify a new DNA aptamer with anti‐hTNF‐α activity. The protein systematic evolution of ligands by exponential enrichment (SELEX) process was used for identifying DNA aptamers. Anti‐hTNF‐α aptamers were selected using dot blot, real‐time PCR, and in vitro inhibitory assay. The selected aptamers were truncated in two steps, and finally, a dimer aptamer was constructed from different selected truncates to improve their inhibitory effect. Also, Etanercept was used as a positive control to inhibit TNF‐α, in comparison to the designed aptamers. After 11 rounds, four aptamers with anti‐hTNF‐α inhibitory effect were identified. The truncation and dimerization strategy revealed a new dimer aptamer with 67 nM Kd, which has 40% inhibitory effect compared with Etanercept (60%). Overall, the dimerization and truncation aptamers could improve its activity. With regard to the several limitations of anti‐TNF‐α proteins therapies including immunogenicity, side effects, and cost‐intensive, a new designed anti‐hTNF‐α dimer aptamer could be considered as a potential therapeutic and/or diagnostic agent for hTNF‐α‐related disorders. [ABSTRACT FROM AUTHOR]

The increased incidence of allergic disorders may be the result of a relative fall in microbial induction in the intestinal immune system during infancy and early childhood. Probiotics have recently been proposed as viable microorganisms for the prevention and treatment of specific allergic diseases. Different mechanisms have been considered for this probiotic property, such as generation of cytokines from activated pro‐T‐helper type 1 after bacterial contact. However, the effects of its immunomodulatory potential require validation for clinical applications. This review will focus on the currently available data on the benefits of probiotics in allergy disease. To improve our knowledge of probiotic bacteria, the aim of this study is to focus on the currently available data on the immunomodulatory role of probiotics in allergy therapy [ABSTRACT FROM AUTHOR]

Abstract: Protein or peptide‐based antigens are the most promising forms to generate custom protective immune responses for clinical applications. Over the last decades, poly(lactic‐co‐glycolic acid) (PLGA) as a biodegradable polymer has gained more attention for delivery of protein and peptide. Besides many appropriate characteristics, to improve its properties to overcome some obstacles such as release profile and it is important instability of antigen during both encapsulation and storage. Therefore, optimized procedures conditions require to be used to maintain the integrity of protein structure under several stress factors in formulation process. In this review article, the properties of PLGA particles, their preparation techniques and strategies for improvement of protein stability during encapsulation into PLGA, release from particle and storage as well as stabilization approaches were summarized. © 2018 Wiley Periodicals, Inc. J. Biomed. Mater. Res. Part A: 106A: 2540–2551, 2018 [ABSTRACT FROM AUTHOR]

Successful recombinant allergen-based immunotherapy has drawn a great deal of attention to use recombinant allergens for new therapeutic and/or diagnostic strategies. The Escherichia coli expression system is frequently used to produce recombinant allergens; however, protein expression in E. coli often results in inclusion bodies. Here, we focused on the expression of two recombinant soluble forms of Pla or 3 using solubility-enhancing peptide tags, human immune deficiency virus type 1 transactivator of transcription core domain and poly-arginine-lysine: rTAT-Pla or 3 and rPoly-Arg-Lys-Pla or 3. Structural characteristics and IgE reactivity of purified recombinant proteins were compared with natural Pla or 3 (nPla or 3) isolated from Platanus orientalis using circular dichroism spectra, fluorescence spectroscopy, and immunoblotting. Likewise, intrinsic viscosity and Stokes radius of the natural and recombinant Pla or 3 allergens were determined to analyze structural compactness in aqueous media. The results indicate high-level solubility and efficient expression of the fusion proteins (rTAT-Pla or 3 and rPoly-Arg-Lys-Pla or 3) compared with the wild-type recombinant. Furthermore, the similar structural characteristics and IgE-binding activities of the fusion proteins to nPla or 3 provide a promising tool for allergy diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Presents the abstracts of articles presented at the 11th International Congress of Immunology slated in July 2001 in Stockholm, Sweden. Rearrangement of antigen receptor genes; Signalling through B and T cell receptors; Molecular mechanisms of apoptosis; Dendritic cells in antigen presentation and inflammatory disorders.

Presents the abstracts of articles presented at the 11th International Congress of Immunology slated in July 2001 in Stockholm, Sweden. Lymphoid organogenesis; Evolution of antigen receptor genes; Selection of B cell repertoires; Lymphoid malignancies; Interaction between APC and T cells; Leukocyte-endothelial cell interactions.