The effect of subacute co-exposure to carbon tetrachloride and diclofenac on the liver of male wistar rats.

Carbon tetrachloride (CCl4) is a potent liver toxin. Diclofenac (Dic), leading adverse effects on the liver, is used among the employees of the industries that use CCl4. The increased use of CCl4 and Dic in industrial workers has prompted us to investigate their synergistic effect on the liver using male Wistar rats as a model. Male Wistar rats were divided into seven groups (n = 6), and the exposure was by intraperitoneal injection for 14 days as follows. Group 1: Control, 2: Olive oil, 3: CCl4 (0.8 mL/kg/day (3 times per week)), 4: Normal saline, 5: Dic (1.5 mg/kg/day per day), 6: Olive oil with normal saline, 7: CCl4 (0.8 mL/kg/day (3 times per week)) and Dic (1.5 mg/kg/day daily). At the end of day 14, the heart blood was collected to measure the liver enzymes, alanine-aminotransferase (ALT), aspartate-aminotransferase (AST), blood alkaline phosphatase (ALP), albumin (ALB), direct bilirubin, and total bilirubin. A pathologist examined the liver tissue. Prism software was used to analyze data using ANOVA and Tukey statistical tests. ALT, AST, ALP, and Total Bilirubin enzymes were increased significantly in the co-administered CCl4 and Dic group, while the ALB levels decreased (p < 0.05). The histological findings reported liver necrosis, focal hemorrhage, adipose tissue change, and lymphocytic portal hepatitis. In conclusion, using Dic while exposed to CCl4 may exacerbate hepatotoxicity in rats. Therefore, it is suggested that more severe restrictions and safety regulations be placed on using CCl4 in the industry, and caution is advised to these industry workers to use Diclofenac.

Inhalation of multi-wall carbon nanotubes changes the expression of apoptosis and cancer genes in rat brain and lungs.

One of the important issues in urban areas is air pollution which causes respiratory disorders. A significant association between exposure to inhaled particulate matter (PM), mainly ultrafine particles, and increased neurological and pulmonary morbidity and mortality was observed in some research. This study aimed to demonstrate the relation between multi-wall carbon nanotubes (MWCNTs) inhalation and the carcinogenic effect of these materials in the brain and lungs. For this purpose, we investigated gene expression in rat brain and lung tissues induced by exposure to MWCNTs. Rats were exposed to MWCNTs in diameters of 10 and 100 nm (pure and impure) at a concentration of 5 mg/m3. Exposure was done through a whole-body exposure chamber for 5 h/day, 5 days/week for 14 days. After exposure, both brain and lung tissues were isolated to evaluate certain gene expressions including Bax, Bcl2, Rac1, Tp53, Mmp12, and Arc. The results showed that exposure to impure and pure MWCNTs (10 and 100 nm) at a concentration of 5 mg/m3 causes up-regulation or down-regulation of some of these genes. The results suggest that impure and pure MWCNTs (10 and 100 nm) can increase the risk of central nervous system disorders such as Alzheimer's disease and increase the risk of carcinogenesis in the lung tissues of rats exposed to MWCNTs (Tab. 2, Fig. 2, Ref. 64). Text in PDF www.elis.sk Keywords: multi-wall carbon nanotube, inhalation, gene expression, carcinogenicity, brain, lung.

Multivesicular liposomal depot system for sustained delivery of risperidone: development, characterization, and toxicity assessment.

OBJECTIVE: Considering the limitations of conventional risperidone (RSP) therapies, the present research characterizes the usefulness of multivesicular liposomes (MVLs) as an efficient controlled-release carrier for this widely used antipsychotic drug, to be employed for the treatment of schizophrenia. METHODS: A 23 full factorial design based on three independent variables was implemented to plan the experiments: the molar ratios of lipid to the drug, triolein to phospholipid, and cholesterol to phospholipid. The impacts of these parameters on the risperidone encapsulation efficiency and its release pattern within the first 24 and 48 h were investigated as dependent variables. Then, the optimized liposomal system was further in-depth analyzed in terms of size, morphological and structural features, release profile over 15 days, biocompatibility, and stability. RESULTS: Optimized formulation parameters gave rise to MVLs possessing a spherical morphology with a median diameter of about 8 µm, a relatively narrow size distribution (span value of 1.49), and an encapsulation efficiency of 57.6%. These carriers not only exhibited a sustained-release behavior in vitro, lasting until the end of the 15 days but also underwent a negligible change in their size and RSP incorporation over two months at refrigerator condition. Furthermore, in vitro cytotoxicity and hemolysis assessments revealed that the optimized MVL formulation is biocompatible. CONCLUSION: This study revealed the potential of MVLs as a promising system for the delivery of RSP and could open a new vista for the successful management of schizophrenia.

Comparison of transmission FTIR and ATR spectra for discrimination between beef and chicken meat and quantification of chicken in beef meat mixture using ATR-FTIR combined with chemometrics.

Detecting meat adulteration for quality control and accurate labeling is important and needs convenient analytical methods. This study aimed to investigate and compare the application of the transmission and ATR approaches of FTIR followed by principal component analysis (PCA) to not only discriminate between chicken and beef meat but also quantizing chicken portion of mixtures. Two different approaches are presented; spectra preprocessing with focus on wavenumber region of 1700-1071 cm-1, and no preprocessed where PCA was applied on the whole spectra range of mid-FTIR. The results suggest that applying PCA on specified preprocessed spectra could detect hidden relationships between variables in chicken and beef in both approaches. PCA successfully clustered these kinds of meats when applied on transmission mode spectra without any preprocessing treatment, while applying it on ATR mode's raw spectra failed to cluster them. Additionally, the preprocessed ATR-FTIR spectrum was used to prepare regression models by Partial Least Square Regression (PLS-R) and artificial neural networks (ANN) for predicting presence and percentage of chicken meat in the beef meat mixture. The results demonstrated the superiority of ANN over PLS-R in this assessment with an R2 of 0.999.

FTIR bio-spectroscopy scattering correction using natural biological characteristics of different cell lines.

Fourier transform infrared (FTIR) spectroscopy is a well-known method of analysis, with various applications, including promising potential for analyzing biological samples. In the bio-spectroscopy of cells, Mie scattering may increase, which then causes spectral distortion, due to the similarity of cell size with the IR medium-wavelength. These changes make the spectrum unreliable. In previous scattering elimination studies, questionable estimations were considered. For instance, all cells were considered as spherical objects or cell size was estimated randomly. In an attempt to provide the best equation based on the natural existence of cells for the FTIR Mie scattering correction, we examined the actual biological data of cells - as opposed to those yielded from mathematical manipulations. So five biological factors: cell size, shape, granularity, circularity, and edge irregularities, for each cell line were considered as factors which cause scattering. For measuring cell size, roundness and edge irregularity, microscopy images were obtained and processed. For evaluating cell line granularity, flow cytometry was used. Finally, by including these factors, an algorithm was designed. To assess the accuracy of the proposed algorithm, the trypsinized cell spectrum was considered as the high scattering spectrum. Cells were also cultured on a MirrIR slide, and their ATR-FTIR spectrum was considered as the minimum scattering spectrum. The algorithm using the abovementioned five characteristics was used for 13 different cell lines, and in some cases the corrected spectrum demonstrated more than 97% resemblance with the ATR spectra of the same cells. A comparison between the results of this algorithm with the Bassan et al. (2017) algorithm for scattering correction that is freely available on the Internet was then conducted on two different cell lines, clearly showing the advantages of our algorithm, in terms of accuracy and precision. Therefore, this method can be viewed as a more suitable solution for scattering correction in cell investigations.

A comparative study of the bispecific monoclonal antibody, blinatumomab expression in CHO cells and E. coli.

The "bispecifics" market improved over the past decade due to the development of many technological platforms including bispecific T cell engagers (BiTEs). The approval of blinatumomab, the most advanced bispecific T-cell engager (BiTE) in clinical trials, can be a significant milestone in the development of bispecific antibodies. Both Chinese hamster ovary (CHO) cells and E. coli strain are considered as the most widely used hosts for the large-scale production of therapeutic monoclonal antibodies. Since both of the economic and qualitative aspects of protein production are important in industry, selection of a suitable protein expression system is very critical. The BsAb gene was cloned into the expression vectors FC550A-1, pcDNA3.1 (+), and PET22b and 6 × His-tagged BsAb then purified on a Ni-NTA chromatography column. Both SDS-PAGE and Western blotting analysis of the purified protein demonstrated that blinatumomab was successfully expressed as a 55 kDa in both expression systems. The antigen-binding properties of blinatumomab were compared in the mammalian system versus Escherichia coli. The results showed that the purified antibody from a mammalian expression system has better binding activity than the one from E. coli host.

Cellular glutathione level does not predict ovarian cancer cells' resistance after initial or repeated exposure to cisplatin.

OBJECTIVE: Cisplatin resistance development is a major obstacle in ovarian cancer treatment. One of the most important mechanisms underlying cisplatin resistance is drug detoxification by glutathione. In the present study, the importance of initial or repeated exposure to cisplatin in glutathione dependent resistance was investigated. To this purpose, some cisplatin sensitive and resistant variants of human ovarian cancer cell lines providing an appropriate range of cisplatin sensitivity were selected. Clonogenic survival assay was performed to evaluate cisplatin resistance and intracellular contents of reduced (GSH) and oxidized (GSSG) glutathione were analyzed using an HPLC method. Our results indicated that the intracellular GSH and GSSG concentrations were nearly equal in A2780 and A2780CP cells, while the A2780CP cells showed 14 times more resistance than the A2780 cells after initial exposure to cisplatin. A2780-R1 and A2780-R3 cells which have been repeatedly exposed to cisplatin also showed no significant difference in glutathione content, even though A2780-R3 was about two times more resistant than A2780-R1. Moreover, intracellular GSH/GSSG ratio decreased in the resistant cells, reflecting a shift towards a more oxidizing intracellular environment indicative of oxidative stress. CONCLUSION: As a conclusion, it seems that although the intracellular glutathione concentration increases after repeated exposure to cisplatin, there is no clear correlation between the intracellular GSH content in ovarian cancer cells and their resistance to cisplatin neither after initial nor after repeated exposure to this drug.

Effect of steroid and serum starvation on a human breast cancer adenocarcinoma cell line.

OBJECTIVE: Breast cancer is one of the most frequent cancers in women. Although there are many treatment protocols for this disease, there are still many patients who do not respond satisfactorily to the current treatment protocols. A better understanding of the nature of the tumor cells might provide a guide for better therapeutic procedures. In this study, the effect of metabolic stress was assessed on the human adenocarcinoma MCF-7 cell line. The cells were seeded in culture plates and after reaching log phase of their growth, cells were exposed to phenol red free-media supplemented with 10%, 0.5%, 0.25% and 0% charcoal-treated serum for 1 to 6 consecutive days. At 24-hour intervals, the cells' ability to proliferate (trypan blue assay), cells mitochondrial content (MTT assay) and intracellular protein content (SRB assay) was assessed. In each day of the study, the cells were released in complete media containing 10% serum for 24 hours and the effect of release was observed on cells. This study showed reduced basal growth rate and proliferation in response to harsh environmental conditions. Protein content of the cells also decreased. Mitochondrial content/activity of the cells however did not decrease, but instead a relative increase was observed at some time points. Releasing the cells caused increased cell proliferation in media with up to 0.5% serum, with an increase in intracellular protein content, although no significant mitochondrial function increase was observed. The results of this study confirm the adaptation of MCF-7 cells to environmental harsh conditions.

Promising anti-inflammatory activity of a novel designed anti-microbial peptide for wound healing.

Chronic wounds can develop as a result of prolonged inflammation during the healing process, which can happen due to bacterial infection. Therefore, preventing infection and controlling inflammation can accelerate wound healing. Antimicrobial peptides have different protective properties in addition to antimicrobial activity. Some of these activities include the stimulation of cytokine or chemokine synthesis, the facilitation of chemotaxis and cell proliferation, the acceleration of cell proliferation, the induction of anti-inflammatory responses, and the promotion of wound repair. This study aimed to assess the wound healing potential of a novel in silico-designed antimicrobial peptide. Then, its anti-inflammatory activity was investigated by measuring the level of tumor necrosis factor-α (TNF-α) and transforming growth factor beta (TGF-ß) as indicators of the wound healing process. In addition, the influence of the peptide on cell migration was evaluated by a scratch test on human dermal fibroblasts (HDF) and HaCaT cells as a human epidermal keratinocyte cell line. The results showed that our new peptide could act well in inhibiting TNF-α over-secretion while increasing the expression of TGF-ß as an anti-inflammatory factor. This peptide showed a significant potential to stimulate HDF and HaCaT cell migration and proliferation. Therefore, using this peptide as an anti-inflammatory component of wound dressings may be promising.

Silica nanoparticles-induced cytotoxicity and genotoxicity in A549 cell lines.

Among the myriad of nanoparticles, silica nanoparticles (SiO2NPs) have gained significant attention since they are extensively produced and used across several kinds of industries. Because of its widespread usage, there has been increasing concern about the potential health effects. This study aims to evaluate the effects of SiO2NPs on Interleukin-6 (IL-6) gene expression in human lung epithelial cell lines (A549). In this study, A549 cells were exposed to SiO2NPs at concentrations of 0, 1, 10, 50, 100, and 200 µg/mL for 24 and 48 h. The IL-6 gene expression was assessed using Real-Time RT-PCR. Additionally, the impact of SiO2NPs on the viability of A549 cells was determined by MTT assay. Statistical analysis was performed using GraphPad Prism software 8.0. MTT assay results indicated a concentration-dependent impact on cell survival. After 24 h, survival decreased from 80 to 68% (1-100 µg/mL), rising to 77% at higher concentrations. After 48 h, survival dropped from 97 to 80%, decreasing to 90% at higher concentrations. RT-PCR showed a dose-response relationship in cellular toxicity up to 10 µg/mL. At higher concentrations, there was increased IL-6 gene expression, mitigating SiO2NP-induced cytotoxic effects. The study shows that the viability and proliferation of A549 cells are impacted by different SiO2NPs concentrations. There may be a potential correlation between IL-6 gene expression reduction and a mechanism linked to cellular toxicity. However, at higher concentrations, an unknown mechanism increases IL-6 gene expression, reducing SiO2NPs' cytotoxic effects. These effects are concentration-dependent and not influenced by exposure times. Further investigation is recommended to determine this mechanism's nature and implications, particularly in cancer research.

High inflammatory cytokines gene expression can be detected in workers with prolonged exposure to silver and silica nanoparticles in industries.

Occupational health must be strictly considered in industries particularly in nanoparticle factories where workers were exposed to different types of chemicals. We measured the serum levels of inflammatory cytokines in workers who developed skin lesions after exposure to silver and silica nanoparticles. Using a questionnaire in this cross-sectional study, we identified 110 workers in nanoparticle industries who were exposed to silver and silica nanoparticles. We also included 40 healthy subjects as controls from the administrative department of the same factories who were not exposed to nanoparticles. Peripheral blood samples used to measure the mRNA levels of inflammatory cytokines by qRT-PCR. In comparison with the control group, the workers who developed skin lesions had significantly higher levels of interleukin IL4, IL6, IL8, and TNF-α, particularly after two or three decades of exposure to silver and silica nanoparticles. Participants who were exposed to silver had higher levels of IL6 and IL8 compared with those who were exposed to silica. Necessary measures must be considered to protect workers in nanoparticle industries against the potential toxic effects of these compounds. Our network pharmacology study suggests corresponding biochemical pathways for these disorders.

Cytotoxic Activity and Phytochemical Analysis of Artemisia haussknechtii Boiss.

Cytotoxic activity of crude extract and fractions (petroleum ether, dichloromethane, and n-butanol) of Artemisia haussknechtii aerial parts was investigated by MTT assay. Dichloromethane fraction showed the highest cytotoxic effect on MCF-7 cell line (IC50 = 297.17 ± 7.99 µg/mL). Phytochemical analysis of the most effective fraction was carried out using normal phase column chromatography (CC) to get eight sub-fractions (A-H). Thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) were used for further purification. Four known compounds with cytotoxic effects on cancer cell lines were isolated from the most active fraction, including 5-Hydroxy-3',4',6,7-tetramethoxyflavone (eupatilin 7-methyl ether), 5-hydroxy 3,3',4',6,7-pentamethoxy-flavone (artemetin), 6-methoxy-7-hydroxycoumarin (scopoletin), and methyl caffeate. Structure elucidation of isolated compounds was done using spectroscopic techniques, including ESIMS and 1D-NMR (1H and 13C). Cytotoxic activity of A. haussknechtii is probably due to coumarin and flavonoid compounds.

Design, Synthesis and Biological Evaluation of 1,3-Diphenyl-3-(phenylthio)propan-1-ones as New Cytotoxic Agents.

Cancers in terms of morbidity and mortality are one of the major universal issues. New compounds of anticancer agents based on ß-aryl-ß-mercapto ketones scaffold possessing piperidinylethoxy or morpholinylethoxy groups were synthesized and evaluated as cytotoxic agents. Cytotoxic effects of synthesized compounds were measured against MCF-7, human ER-positive breast cancer cell lines, using MTT assay. The results indicated that all compounds had high cytotoxic activity on MCF-7 cancerous cells, even more than the reference drug Tamoxifen. Among them, compounds 3-(4-(2-morpholinoethoxy)phenyl)-1-phenyl-3-(phenylthio)propan-1-one (4a) and 1-(4-methoxyphenyl)-3-(3-(2-morpholinoethoxy)phenyl)-3-(phenylthio)propan-1-one (4h) had no significant cytotoxic effects on normal cells compared to Tamoxifen. Our results also indicated that adding tertiary amine basic side chain, found in Tamoxifen drug, to 1,3-diphenyl-3-(phenylthio)propan-1-ones improves the cytotoxic effects of these compounds on breast cancer cells.

Assessing the risk of main activities of nanotechnology companies by the NanoTool method.

Purpose. Nanotechnology can be considered one of the greatest developments over the past few decades. Despite many applications of nanomaterials in various fields, there are concerns about their effects on humans and the environment. Therefore, this study was conducted to assess the risk level of activities involving nanomaterials in nanotechnology companies in Tehran, Iran. Materials and methods. After identifying the main activities of 18 nanotechnology companies, these activities were assessed using the NanoTool method, which is a method for assessing risks of activities involving nanomaterials. Data were analyzed using SPSS version 22. Results. The results showed that in six activities (33.30%) the risk level was 4 (RL4), in eight activities (44.40%) the risk level was 3 (RL3) and four activities (22.30%) had risk level 2 (RL2). Also, it was found that 78.88% of the controls used by these companies were not enough to reduce the risks of nanomaterials and need to be upgraded. Conclusions. The high level of risk in the activities involving nanomaterials shows that there are serious problems regarding the safety of nanomaterials in the nanotechnology companies in Tehran, Iran.

Ficus deltoidea ameliorates biochemical, hormonal, and histomorphometric changes in letrozole-induced polycystic ovarian syndrome rats.

BACKGROUND: Insulin resistance and hormonal imbalances are key features in the pathophysiology of polycystic ovarian syndrome (PCOS). We have previously shown that Ficus deltoidea var. deltoidea Jack (Moraceae) can improve insulin sensitivity and hormonal profile in PCOS female rats. However, biological characteristics underpinning the therapeutic effects of F. deltoidea for treating PCOS remain to be clarified. This study aims to investigate the biochemical, hormonal, and histomorphometric changes in letrozole (LTZ)-induced PCOS female rats following treatment with F. deltoidea. METHODS: PCOS was induced in rats except for normal control by administering LTZ at 1 mg/kg/day for 21 days. Methanolic extract of F. deltoidea leaf was then orally administered to the PCOS rats at the dose of 250, 500, or 1000 mg/kg/day, respectively for 15 consecutive days. Lipid profile was measured enzymatically in serum. The circulating concentrations of reproductive hormone and antioxidant enzymes were determined by ELISA assays. Ovarian and uterus histomorphometric changes were further observed by hematoxylin and eosin (H&E) staining. RESULTS: The results showed that treatment with F. deltoidea at the dose of 500 and 1000 mg/kg/day reduced insulin resistance, obesity indices, total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL), malondialdehyde (MDA), testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) to near-normal levels in PCOS rats. The levels of high-density lipoprotein cholesterol (HDL), estrogen, and superoxide dismutase (SOD) are also similar to those observed in normal control rats. Histomorphometric measurements confirmed that F. deltoidea increased the corpus luteum number and the endometrial thickness. CONCLUSIONS: F. deltoidea can reverse PCOS symptoms in female rats by improving insulin sensitivity, antioxidant activities, hormonal imbalance, and histological changes. These findings suggest the potential use of F. deltoidea as an adjuvant agent in the treatment program of PCOS.

Microfluidic platform for synthesis and optimization of chitosan-coated magnetic nanoparticles in cisplatin delivery.

In this study, magnetic core/chitosan shell Nanoparticles (NPs) containing cisplatin were synthesized via cisplatin complexation with tripolyphosphate as the chitosan crosslinker using two different procedures: a conventional batch flow method and a microfluidic approach. An integrated microfluidic device composed of three stages was developed to provide precise and highly controllable mixing. The comparison of the results revealed that NPs synthesized in microchannels were monodisperse 104 ±â€¯14.59 nm (n = 3) in size with optimal morphological characteristics, whereas polydisperse 423 ±â€¯53.33 nm (n = 3) nanoparticles were obtained by the conventional method. Furthermore, cisplatin was loaded in NPs without becoming inactivated, and the microfluidic technique demonstrated higher encapsulation efficiency, controlled release, and consequently lower IC50 values during exposure to the A2780 cell line proving that microfluidic synthesized NPs were able to enter the cells and release the drug more efficiently. The developed microfluidic platform presents valuable features that could potentially provide the clinical translation of NPs in drug delivery.

Generation and molecular docking analysis of specific single-chain variable fragments selected by phage display against the recombinant nucleocapsid protein of fig mosaic virus.

The mosaic disease caused by fig mosaic virus (FMV) is considered the plague of fig worldwide. A naïve phage display library, raised against the recombinant nucleocapsid protein of FMV (FMV-Np) was screened to obtain specific monoclonal recombinant antibodies in the form of single chain variable fragments (scFvs). After three rounds of biopanning, the bacterially expressed FMV-Np was used as an antigen for selecting specific phages for the production of specific soluble scFvs to be used in immunological assays. The binding specificity of scFvs against FMV-infected fig samples was evaluated by immunoblotting and Plate trapped antigen-ELISA (PTA-ELISA), which revealed efficient of the resultant scFvs to the target antigen. Silico homology-modelling and molecular docking analysis confirmed the scFv and FMV-Np interactions with the anti-FMV-Np scFv through an estimated binding energy of -650 kj mol-1; considered to be generated from the interactions between 13 amino acids residues predicted as putative epitopes in the interface pocket of FMV-Np and scFv antibody. This high affinity was further confirmed in the specificity of ELISA and immunoblotting assays. This is the first report on the application of phage display technology to generate specific recombinant scFvs against FMV that can be applied in development of antibody-mediated protection strategy to control the fig mosaic disease.

Identification and Quantification of Texture Soy Protein in A Mixture with Beef Meat Using ATR-FTIR Spectroscopy in Combination with Chemometric Methods.

Meat, as an important source of protein, is one of the main parts of many people's diet. Due to economic interests and thereupon adulteration, there are special concerns on its accurate labeling. In this study Fourier transform infrared (ATR-FTIR) spectroscopy combined with chemometric techniques (principal component analysis (PCA), artificial neural networks (ANNs), and partial least square regression (PLS-R)) were employed for discrimination of pure beef meat from textured soy protein plus detection and quantification of texture soy protein in a mixture with beef meat. Spectral preprocessing was carried out on each spectra including Savitzki-Golay (SG) smoothing filter, Standard Normal Vitiate (SNV), scatter correction (MSC), and min-max normalization. Spectral range 1700-1071 cm-1 was selected for further analysis. Principal component analysis showed discrete clustering of pure samples. In the next step, supervised artificial neural networks (ANNs) were performed for classification and discrimination. The results showed classification accuracy of 100% using this model. Furthermore, PLS-R model correlated the actual and FTIR estimated values of texture soy protein in beef meat mixture with coefficient of determination (R2) of 0.976. In conclusion, it was demonstrated that ATR-FTIR spectroscopy along with PCA and ANNs analysis might potentially replace traditional laborious and time-consuming analytical techniques to detect adulteration in beef meat as a rapid, low cost, and highly accurate method.

Construction of a Mammalian IRES-based Expression Vector to Amplify a Bispecific Antibody; Blinatumomab.

Blinatumomab, the bispecific T cell engager antibody (BsAb), has been demonstrated as the most successful BsAb to date. Throughout the past decade, vector design has great importance for the expression of monoclonal antibody in Chinese hamster ovary (CHO) cells. It has been indicated that expression vectors based on the elongation factor-1 alpha (EF-1 alpha) gene and DHFR selection marker can be highly effective to produce populations of stably transfected cells in the selection medium. Moreover, the phiC31 integrase system is considered as an attractive and safe protein expression system in mammalian cells and it could integrate a donor plasmid of any size, as a single copy, in to the host genome with no cofactors. In this study, phiC31 integrase technology in combination with DHFR amplification system was used to have an expression vector for future expression of blinatumomab in CHO cells. The gene of interest (BsAb gene) could be joined to DHFR selection marker with the insertion of an internal ribosome entry site (IRES). By positioning the DHFR downstream of BsAb gene and IRES, the transcription of the selection marker can depend on the successful transcription of the BsAb gene, which was located upstream in the expression construct. In this study, FC550A-1 vector was used as the backbone and DHFR selection marker was successfully combined with phiC31 integrase technology to generate a high-expressing construct for BsAb expression in CHO-DG44 cells in future studies.

The Photothermal Effect of Targeted Methotrexate-Functionalized Multi-Walled Carbon Nanotubes on MCF7 Cells.

Our goal is to reduce the release rate of methotrexate (MTX) and increase cell death efficiency.Carboxylated multi-walled carbon nanotubes (MWCNT-COOH) were functionalized with MTX as a cytotoxic agent, FA as a targeting moiety and polyethylene amine (PEI) as a hydrophilic agent. Ultimately, MWCNT-MTX and MWCNT-MTX-PEI-FA were synthesized. Methotrexate release studies were conducted in PBS and cytotoxic studies were carried out by means of the MTT tassay. Methotrexate release studies from these two carriers demonstrated that the attachment of PEI-FA onto MWCNT-MTX reduces the release rate of methotrexate. The IC50 of MWCNT-MTX-PEI-FA and MWCNT-MTX have been calculated as follows: 9.89 ± 0.38 and 16.98 ± 1.07 µg/mL, respectively. Cytotoxic studies on MWCNT-MTX-PEI-FA and MWCNT-MTX in the presence of an IR laser showed that at high concentrations, they had similar toxicities due to the MWCNT's photothermal effect. Targeting effect studies in the presence of the IR laser on the cancer cells have shown that MWCNT-MTX-PEI-FA, MWCNT-MTX, and f-MWCNT have triggered the death of cancer cells by 55.11 ± 1.97%, 49.64 ± 2.44%, and 37 ± 0.70%, respectively. The release profile of MTX in MWCNT-MTX-PEI-FA showed that the presence of PEI acts as a barrier against release and reduces the MTX release rate. In the absence of a laser, MWCNT-MTX-PEI-FA exhibits the highest degree of cytotoxicity. In the presence of a laser, the cytotoxicity of MWCNT-MTX and MWCNT-MTX-PEI-FA has no significant difference. Targeting studies have shown that MWCNT-MTX-PEI-FA can be absorbed by cancer cells exclusively.