Jalal Abdolalizadeh

Vitamin D Receptor Gene Polymorphism and Vitamin D Plasma Concentration: Correlation with Susceptibility to Tuberculosis

PURPOSEnIt is estimated that one third of the worlds population were infected with M. tuberculosis, but only 10% of them have developed in to disease form. This subject refers to differences in host immune system activity against the tuberculosis. Vitamin D and its receptor (VDR) are important factors in the host innate immune system against the tuberculosis. In the present study VDR gene polymorphisms and its relationship with plasma vitamin D levels in susceptibility to tuberculosis have been investigated.nnnMETHODSnThe subjects were 84 patients with tuberculosis and 90 healthy controls. Vitamin D levels were measured in all study participants. DNA was isolated from the blood leukocytes of all groups and amplified by polymerase chain reaction (PCR). Then restriction fragment length polymorphism (RFLP) was performed on each PCR products to study the VDR gene polymorphisms. The statistical analyses were conducted using SPSS.nnnRESULTSnThere was no statistically significant relationship between polymorphisms of FokI, BsmI, ApaI and TaqI in VDR gene and susceptibility to tuberculosis. Vitamin D deficiency and susceptibility to tuberculosis were closely related (95% CI -0.08 - 4.7, P = 0.059). Also the relationship between plasma vitamin D levels and frequency of FokI-ff gene polymorphism was significant in all study participants (P = 0.045).nnnCONCLUSIONnWhen the genotype frequencies of VDR gene polymorphisms were analyzed with respect to plasma vitamin D levels, a significant association was seen. As an enhancement in plasma vitamin D levels in individuals (with FokI-ff genotype and low levels of vitamin D) may protect them against active tuberculosis.

LARGE SCALE GENERATION AND CHARACTERIZATION OF ANTI-HUMAN CD34 MONOCLONAL ANTIBODY IN ASCETIC FLUID OF BALB/C MICE

PURPOSEnMonoclonal antibodies or specific antibodies are now an essential tool of biomedical research and are of great commercial and medical value. The purpose of this study was to produce large scale of monoclonal antibody against CD34 in order to diagnostic application in leukemia and purification of human hematopoietic stem/progenitor cells.nnnMETHODSnFor large scale production of monoclonal antibody, hybridoma cells that produce monoclonal antibody against human CD34 were injected into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. 5 ml ascitic fluid was harvested from each mouse in two times. Evaluation of mAb titration was assessed by ELISA method. The ascitic fluid was examined for class and subclasses by ELISA mouse mAb isotyping Kit. mAb was purified from ascitic fluid by affinity chromatography on Protein A-Sepharose. Purity of monoclonal antibody was monitored by SDS -PAGE and the purified monoclonal antibody was conjugated with FITC.nnnRESULTSnMonoclonal antibodies with high specificity and sensitivity against human CD34 by hybridoma technology were prepared. The subclass of antibody was IgG1 and its light chain was kappa.nnnCONCLUSIONnThe conjugated monoclonal antibody could be a useful tool for isolation, purification and characterization of human hematopoietic stem cells.

Targeting Cytokines: Production and Characterization of Anti-TNF-α scFvs by Phage Display Technology

The antibody display technology (ADT) such as phage display (PD) has substantially improved the production of monoclonal antibodies (mAbs) and Ab fragments through bypassing several limitations associated with the traditional approach of hybridoma technology. In the current study, we capitalized on the PD technology to produce high affinity single chain variable fragment (scFv) against tumor necrosis factor-alpha (TNF- α), which is a potent pro-inflammatory cytokine and plays important role in various inflammatory diseases and malignancies. To pursue production of scFv antibody fragments against human TNF- α, we performed five rounds of biopanning using stepwise decreased amount of TNF-α (1 to 0.1 μ g), a semi-synthetic phage antibody library (Tomlinson I + J) and TG1 cells. Antibody clones were isolated and selected through enzyme-linked immunosorbent assay (ELISA) screening. The selected scFv antibody fragments were further characterized by means of ELISA, PCR, restriction fragment length polymorphism (RFLP) and Western blot analyses as well as fluorescence microscopy and flow cytometry. Based upon binding affinity to TNF-α , 15 clones were selected out of 50 positive clones enriched from PD in vitro selection. The selected scFvs displayed high specificity and binding affinity with Kd values at nm range to human TNF-α . The immunofluorescence analysis revealed significant binding of the selected scFv antibody fragments to the Raji B lymphoblasts. The effectiveness of the selected scFv fragments was further validated by flow cytometry analysis in the lipopolysaccharide (LPS) treated mouse fibroblast L929 cells. Based upon these findings, we propose the selected fully human anti-TNF-α scFv antibody fragments as potential immunotherapy agents that may be translated into preclinical/clinical applications.

Overview of Albumin and Its Purification Methods

As the most frequent plasma protein, albumin constitutes more than 50% of the serum proteins in healthy individuals. It has a key role in oncotic pressure maintenance and it is known as a versatile protein carrier for transportation of various endogenous and exogenous ligands. Reduced amounts of albumin in the body will lead to different kinds of diseases such as hypovolemia and hypoproteinemia. It also has various indications in shocks, burns, cardiopulmonary bypass, acute liver failure and etc. Further applications in research consist of cell culture supplement, drug delivery carrier and protein/drug stabilizer. So, the demand for albumin increased annually worldwide. Due to different applications of albumin, many efforts have been accomplished to achieve albumin during a long period of time. In this review, an overview of serum albumin and different purification methods are summarized.

Investigating Apoptotic Effects of Methanolic Extract of Dorema glabrum Seed on WEHI-164 Cells

We aimed to investigate the apoptotic effects of the methanolic extract of Dorema glabrum seed on WEHI-164, cancerous cells in comparison with L929, normal cells and compared them with the cytotoxic effects of Taxol. So, MTT test and DNA fragmentation assay were performed on cultured and treated cells. Also electrophoresis which was followed by immunoblotting was done to survey the production of Caspase-3 and Bcl2 proteins, and to inquire into their relative genes expression, RT-PCR was used. According to our findings, the methanolic extract of Dorema glabrum seed can alter cells morphology as they shrink and take a spherical shape and lose their attachment too. So, the plant extract inhibits cell growth albeit in a time- and dose-dependent manner and results in degradation of chromosomal DNA. Induction of apoptosis by the plant extract was proved by the reduction of pro-Caspase-3 and Bcl2 proteins and increase in Caspase-3 gene expression and decrease in that of bcl2 too. Our data well established the antiproliferative effect of methanolic extract of Dorema glabrum seed and clearly showed that the plant extract can induce apoptosis and not necrosis in vitro. These results demonstrated that Dorema glabrum seed might be a novel and attractive therapeutic candidate for tumor treatment.

Affinity Purification of Tumor Necrosis Factor-α Expressed in Raji Cells by Produced scFv Antibody Coupled CNBr-Activated Sepharose

PURPOSEnRecombinant tumor necrosis factor-alpha (TNF-α) has been utilized as an antineoplastic agent for the treatment of patients with melanoma and sarcoma. It targets tumor cell antigens by impressing tumor-associated vessels. Protein purification with affinity chromatography has been widely used in the downstream processing of pharmaceutical-grade proteins.nnnMETHODSnIn this study, we examined the potential of our produced anti-TNF-α scFv fragments for purification of TNF-α produced by Raji cells. The Raji cells were induced by lipopolysaccharides (LPS) to express TNF-α. Western blotting and Fluorescence-activated cell sorting (FACS) flow cytometry analyses were used to evaluate the TNF-α expression. The anti-TNF-α scFv selected from antibody phage display library was coupled to CNBr-activated sepharose 4B beads used for affinity purification of expressed TNF-α and the purity of the protein was assessed by SDS-PAGE.nnnRESULTSnWestern blot and FACS flow cytometry analyses showed the successful expression of TNF-α with Raji cells. SDS-PAGE analysis showed the performance of scFv for purification of TNF-α protein with purity over 95%.nnnCONCLUSIONnThese findings confirm not only the potential of the produced scFv antibody fragments but also this highly pure recombinant TNF-α protein can be applied for various in vitro and in vivo applications.

CYTOTOXIC EFFECTS OF ALCOHOLIC EXTRACT OF DOREMA GLABRUM SEED ON CANCEROUS CELLS VIABILITY

PURPOSEnIn the present study cytotoxic effects of the alcoholic extract of Dorema Glabrum seed on viability of WEHI-164 cells, mouse Fibrosarcoma cell line and L929 normal cells were compared with the cytotoxic effects of Taxol (anticancer and apoptosis inducer drug).nnnMETHODSnTo find out the plant extract cytotoxic effects, MTT test and DNA fragmentation assay, the biochemical hallmark of apoptosis were performed on cultured and treated cells.nnnRESULTSnAccording to the findings the alcoholic extract of Dorema Glabrum seed can alter cells morphology and because of chromatin condensation and other changes they shrink and take a spherical shape, and lose their attachment too. So the plant extract inhibits cell growth albeit in a time and dose dependent manner and results in degradation of chromosomal DNA.nnnCONCLUSIONnOur data well established the anti-proliferative effect of methanolic extract of Dorema Glabrum seed and clearly showed that the plant extract can induce apoptosis and not necrosis in vitro, but the mechanism of its activities remained unknown. These results demonstrated that Dorema Glabrum seed might be a novel and attractive therapeutic candidate for tumor treatment in clinical practices.

Antiproliferative and Apoptotic Effects of Novel Anti-ROR1 Single-Chain Antibodies in Hematological Malignancies

Receptor tyrosine kinase–like orphan receptor (ROR) proteins are a conserved family of tyrosine kinase receptors that function in developmental processes including cell survival, differentiation, cell migration, cell communication, cell polarity, proliferation, metabolism, and angiogenesis. ROR1 has recently been shown to be expressed in various types of cancer cells but not normal cells. Pharmacokinetics and pharmacodynamics of single-chain Fragment variable (scFv) antibodies provide potential therapeutic advantages over whole antibody molecules. In the present study, scFvs against a specific peptide from the extracellular domain of ROR1 were selected using phage display technology. The selected scFvs were further characterized using polyclonal and monoclonal phage enzyme-linked immunosorbent assay (ELISA), soluble monoclonal ELISA, colony PCR, and sequencing. Antiproliferative and apoptotic effects of selected scFv antibodies were also evaluated in lymphoma and myeloma cancer cell lines using MTT and annexin V/PI assays. The results of ELISA indicated specific reactions of the isolated scFvs against the ROR1 peptide. Colony PCR confirmed the presence of full-length VH and Vκ inserts. The percentages of cell growth after 24 h of treatment of cells with individual scFv revealed that the scFv significantly inhibited the growth of the RPMI8226 and chronic lymphocytic leukemia (CLL) cells in comparison with the untreated cells (p < 0.05). Interestingly, 24-h treatment with specific scFv induced apoptosis cell death in the RPMI8226 and CLL cells. Taken together, our results demonstrate that targeting of ROR1 using peptide-specific scFv can be an effective immunotherapy strategy in hematological malignancies.

Effect of Culture Condition Variables on Human Endostatin Gene Expression in Escherichia coli Using Response Surface Methodology.

Background Recombinant human endostatin (rhES) is an angiogenesis inhibitor used as a specific drug for the treatment of non-small-cell lung cancer. As mRNA concentration affects the recombinant protein expression level, any factor affecting mRNA concentration can alter the protein expression level. Response surface methodology (RSM) based on the Box-Behnken design (BBD) is a statistical tool for experimental design and for optimizing biotechnological processes. Objectives This investigation aimed to predict and develop the optimal culture conditions for mRNA expression of the synthetic human endostatin (hES) gene in Escherichia coli BL21 (DE3). Materials and Methods The hES gene was amplified, cloned, and expressed in the E. coli expression system. Three factors, including isopropyl β-D-1-thiogalactopyranoside (IPTG) concentration, post-induction time, and cell density before induction, were selected as important factors. The mRNA expression level was determined using real-time PCR. The expression levels of hES mRNA under the different growth conditions were analyzed. SDS-PAGE and western blot analyses were carried out for further confirmation of interest-gene expression. Results A maximum rhES mRNA level of 376.16% was obtained under the following conditions: 0.6 mM IPTG, 7 hours post-induction time, and 0.9 cell density before induction. The level of rhES mRNA was significantly correlated with post-induction time, IPTG concentration, and cell density before induction (P < 0.05). The expression of the hES gene was confirmed by western blot. Conclusions The obtained results indicate that RSM is an effective method for the optimization of culture conditions for hES gene expression in E. coli.

Cloning and Expression of Recombinant Human Endostatin in Periplasm of Escherichia coli Expression System.

PURPOSEnRecombinant human endostatin (rhEs) is an angiogenesis inhibitor which is used as a specific drug in the treatment of non-small-cell lung cancer. In the current research, we developed an efficient method for expressing soluble form of the rhEs protein in the periplasmic space of Escherichia coli via fusing with pelB signal peptide.nnnMETHODSnThe human endostatin (hEs) gene was amplified using synthetic (hEs) gene as a template; then, cloned and expressed under T7 lac promoter. IPTG was used as an inducer for rhEs expression. Next, the osmotic shock was used to extraction of protein from the periplasmic space. The presence of rhEs in the periplasmic space was approved by SDS-PAGE and Western blotting.nnnRESULTSnThe results show the applicability of pelB fusion protein system usage for secreting rhEs in the periplasm of E. coli in the laboratory scale. The rhEs represents approximately 35 % (0.83mg/l) of the total cell protein.nnnCONCLUSIONnThe present study apparently is the first report of codon-optimized rhEs expression as a fusion with pelB signal peptide. The results presented the successful secretion of soluble rhEs to the periplasmic space.