Avicenna journal of medical biotechnology最新文献

Background: Myeloid Derived Suppressor Cells (MDSCs) are capable of inhibiting both innate and adaptive immune responses and accumulate in the microenvironment of breast tumors. Hence, MDSC depletion by chemotherapeutic agents can improve clinical efficacy of cancer immunotherapy. The effects of 5-FU and doxorubicin agents on MDSC reduction in 4T1 breast cancer murine model were evaluated.

Methods: 5×10⁵ of 4T1 tumor cells were injected into mammary fat pad of BALB/c female mice. Tumor bearing mice were randomly divided into 4 groups: PBS receiving control group, doxorubicin receiving groups at doses of 2.5 and 5 mg/kg, and 5-FU receiving group at dose of 50 mg/kg. Doxorubicin and 5-FU agents were intraperitoneally administrated at three doses with 5-day intervals and five doses for three times a week, respectively. Then, on day 20 post tumor cells injection, spleens and tumors were isolated to determine frequency of CD11b⁺ Gr1⁺ MDSCs by flow cytometry analysis.

Results: 5-FU was able to reduce significantly both splenic and interatumoral MDSCs comparing to control group (p=0.0276 and p=0.0067, respectively). Also, Doxorubicin treatment at dose of 50 mg/kg was associated to a significant reduction of splenic MDSCs in comparison to untreated group (p=0.0382). However, only 5-FU injection led to inhibit notably tumor growth in comparison to control group (p=0.0139).

Conclusion: Findings show that 5-FU has inhibitory effects on MDSCs and tumor growth in 4T1 tumor model. So, more investigations are needed to study combination of 5-FU with immune based approaches to enhance the efficacy of cancer therapies.

The age of synthetic biology is ushering in new technologies for the advancement of society, human health, and agriculture. It appears that synthetic biology has integrated engineering paradigms into biological contexts. The combined use of new biotechnology and synthetic biology raises concerns about biosafety, biosecurity, and even cyberbiosecurity. For example, synthetic biology increases the possibility of designing, developing, and deploying pathogenic bioweapons in new and different ways than natural pathogens, as well as manipulating the genome. Evaluation of new technologies and platforms that enable creative or destructive manipulation of biological materials, systems, and organisms is important to identify potential security opportunities and vulnerabilities. This issue poses challenges to the medical community and civilian populations worldwide, creating a growing need to implement and enforce standardized biosafety and biosecurity regulations to protect humans, animals, plants, and the environment. It is critical to establish rules and management guidelines, provide strong leadership at the individual and institutional levels, and utilize established biosafety and biosecurity tools to mitigate the risks associated with synthetic biology. This review addresses the current state of synthetic biology, focusing on the concepts of biosafety, biosecurity, and cyberbiosecurity, as well as enhancing the standardization, regulation, and management of biosecurity in synthetic biology. In this review, the current situation in the Middle East region has been discussed and the challenges and opportunities encountered by synthetic biology researchers in this area is explored. The Middle East region is vulnerable to bioterrorism due to various factors. However, some countries in this strategically important region face challenges as they lack the necessary resources to effectively combat this significant global threat. These attacks are not limited to a specific border or area; they can affect multiple countries or have a global impact.

Background: Brucellosis in livestock and its transmission to humans through the consumption of contaminated dairy products is an important issue. The introduction of new approaches using immunogenic proteins against and diagnosing brucellosis is a serious issue in human health.

Methods: Brucella abortus contains five proteins including: MOXR family ATPase-α2, T9SS C-terminal target domain-containing protein, Cobyric acid synthase, Hypothetical protein, and VirB11 type IV Secretion protein, which were considered and the designed recombinant polypeptide was produced and evaluated. The pure recombinant protein ABOR with 549aa in combination with chitin as an adjuvant was injected subcutaneously into guinea pigs to evaluate their immunity responses.

Results: The results indicated that the ABOR recombinant protein induced Th1 immunity with high levels of specific IgG (IgG2a) as well as Interferon-γ (IFN-γ), Interleukin-2 (IL-2), IL-12, and Tumor Necrosis Factor-alpha (TNF-α), compared to the control group. Th1/Th2 ratio analysis demonstrated the efficacy of ABOR protein combined with chitin in stimulating cellular immunity in the animals.

Conclusion: Designed recombinant polypeptide combined with chitin showed ability for induction of cellular and humoral immunity an guinea pigs compared to RB51 vaccine.

Background: Diabetic Foot Ulcer (DFU) might be worsened by neuropathy and vascular issues. This condition can cause 14.3% fatality, stressing the need for effective wound healing therapy. Wound healing is a complex biological process, and human Wharton's Jelly Mesenchymal Stem Cells (hWJMSCs) may help manage DFU treatment issues. This research focuses on utilizing a gel carrier to deliver bioactive substances from Wharton's Jelly Mesenchymal Stem Cells secretome (hWJ-MSCs-Sec) as a possible treatment for DFU.

Methods: To maintain quality, hWJMSCs-Sec is thoroughly mixed with carbomer gel and freeze-dried. ELISA test is performed to determine the characterization of the gel of hWJMSCs-Sec such as Keratinocyte Growth Factor (KGF), Platelet-Derived Growth Factor (PDGF), Hepatocyte Growth Factor (HGF), Epidermal Growth Factor (EGF), and Heparin-Binding EGF-Like Growth Factor (HB-EGF). The antioxidant activity was also measured with Hydrogen peroxide (H₂O₂), Nitric oxide (NO), and Ferric Reducing Antioxidant Power (FRAP) assay. Proliferation assay was utilized using WST-8 and the wound healing potential was assessed via the migration cell ability of scratched-human skin fibroblast (BJ cells).

Results: The freeze-dried hWJ-MSCs-Sec showed higher levels of KGF, HGF, PDGF, EGF, HB-EGF, and the antioxidant activities compared to fresh hWJ-MSCs-Sec. Additionally, the gel of freeze-dried hWJ-MSCs-Sec exhibited higher levels compared to the gel of fresh hWJMSCs-Sec. This was evidenced by faster closure of scratched wounds on BJ cells treated with hWJMSCs-Sec and freeze-dried hWJ-MSCs-Sec gel.

Conclusion: The freeze-dried hWJ-MSCs-Sec gel exhibits superior quality compared to the non-freeze-dried hWJ-MSCs-Sec gel. This demonstrates that the freeze-drying procedure can maintain the bioactive chemicals found in hWJMSCs-Sec, potentially enhancing the efficacy of this gel in promoting cell regeneration for wound healing.

Background: Simulated Physiological Oocyte Maturation (SPOM) mimics in vitro the physiological events of oocyte maturation in the presence of cAMP modulators. These modulators increase the intracellular concentrations of cAMP, which inhibits the immediate resumption of meiosis and gives the oocyte more time to gain optimal developmental competence. In addition, L-carnitine helps to increase the energy supply of cells through the β-oxidation of fatty acids. This study aimed to investigate the effect of SPOM and L-carnitine supplementation during In Vitro Maturation (IVM) and In Vitro Culture (IVC) on the developmental competence of bovine oocytes.

Methods: Ovarian Cumulus Complexes (COCs) were cultured in the presence or absence of forskolin+IBMX during the first 2 hr of IVM (pre-IVM) with or without L-carnitine (LC) during IVM or IVC in six experimental groups as follows: I) pre-IVM (pre-IVM group), II) pre-IVM with L-carnitine supplementation during IVM (pre-IVM/LC group), III) L-carnitine supplementation during IVM (IVM/LC group), IV) L-carnitine supplementation during in vitro culture (IVC/LC group), V) pre-IVM+ IVC/LC group, and VI) no treatment during IVM and IVC (Control group). The cleavage and blastocyst rates, the blastocysts' total cells number, and the expression of Nanog, Bax, Oct4, Cdx2, and Ifnt genes in resulting blastocysts were assessed. To assess differences among experimental groups, a one-way analysis of variance was initially employed, followed by post hoc Fisher LSD. The difference between groups was considered statistically significant when p<0.05.

Results: The cleavage and blastocyst rates in the Pre-IVM and Pre-IVM/LC groups was higher than control group and other groups (p≤0.05) except for IVC/LC and IVM/LC groups, respectively. The number of blastocyst's Inner Cell Mass (ICM) in pre-IVM and Pre-IVM/LC groups as well as the ratio of ICM/TE were higher than control group (p<0.05). The expression of OCT4, CDX2, and IFNT increased in both the pre-IVM and pre-IVM/LC groups compared to the control group (p<0.05).

Conclusion: In conclusion, the application of SPOM-adapted IVM and L-carnitine during IVM of bovine oocyte improves the quantity and quality of the resulting embryos.

Background: Despite the success of "direct-acting antivirals" in treating Hepatitis C Virus (HCV) infection, invention of a preventive HCV vaccine is crucial for global elimination of the virus. Recent data indicated the importance of the induction of Pangenomic neutralizing Antibodies (PnAbs) against heterogenic HCV Envelope 2(E2), the cellular receptor binding antigen, by any HCV vaccine candidate. To overcome HCVE2 heterogeneity, "generation of consensus HCVE2 sequences" is proposed. However, Consensus Sequence (CS) generating algorithms such as "Threshold" and "Majority" have certain limitations including "Threshold-rigidity" which leads to induction of undefined residues and insensitivity of the "Majority" towards the "evolutionary cost of residual substitutions".

Methods: Herein, first a modification to the "Majority" algorithm was introduced by incorporating BLOSUM matrices. Secondly, the HCVE2 sequences generated by the "Fitness" algorithm (using 1698 sequences from genotypes 1, 2, and 3) was compared with those generated by the "Majority" and "Threshold" algorithms using several in silico tools.

Results: Results indicated that only "Fitness" provided completely defined, gapless HCVE2s for all genotypes/subtypes, while considered the evolutionary cost of amino acid replacements (main "Majority/Threshold" limitations) by substitution of several residues within the generated consensuses. Moreover, "Fitness-generated HCVE2 CSs" were superior for antigenic/immunogenic characteristics as an antigen, while their positions within the phylogenetic trees were still preserved.

Conclusion: "Fitness" algorithm is capable of generating superior/optimum HCVE2 CSs for inclusion in a pan-genomic HCV vaccine and can be similarly used in CS generation for other highly variable antigens from other heterogenic pathogens.

Chronic Lymphocytic Leukemia (CLL) is a clinically and biologically heterogeneous disease with a variable clinical course. The induction of a generalized state of immuno-suppression, leading to susceptibility to infections and the failure of anti-tumor immune responses, is a key feature of the clinical course of CLL. In addition to B-cell receptor (BCR) signaling in CLL, several receptor tyrosine kinases (RTKs) have been reported to be constitutively active in leukemic B cells, resulting in promoted survival and resistance to apoptosis induced by chemotherapy. Several treatment options are available for CLL, including a watch-and-wait strategy, chemotherapy, targeted therapies, immunotherapies such as adoptive cellular therapy (CAR T-Cell Therapy), stem cell transplantation (allogeneic transplantation), radiation therapy and surgery. The identification of Tumor-Associated Antigens (TAAs) is the bottleneck of tumor immunology and immunotherapy, serving as promising targets for precise diagnosis, monitoring, or therapeutic approaches. Numerous TAAs have been identified, and their application in immunotherapy holds promise for the treatment of CLL. Furthermore, extensive ongoing research aims to identify new cancer TAAs. In this review, our objective is to provide a comprehensive overview of CLL immunology and recent findings regarding advances in TAAs with therapeutic applications in CLL.

Background: The low solubility of Tobacco Etch Virus (TEV) protease, a functional enzyme that cleaves protein tags without significant modification in its sequence, is one of the most important limitations of this enzyme. In this study, the aim was to increase the solubility of TEV by changing the expression conditions and designing lysis buffer with various solubilizing agents to improve its solubility.

Methods: Escherichia coli (E. coli) BL21 (DE3) and E. coli origami harboring wild type TEV-pKR793 and mutant N23F TEV-pKR793 plasmids were used for the expression. Response surface methodology was used to determine the best culture conditions (IPTG concentration, incubation time and incubation temperature) of soluble expression. Furthermore, eight different solubilizing agents were added separately to the lysis buffer to check their effect on the protein solubility.

Results: The production of soluble N23F in E. coli BL21 (DE3) was two-folds more than the wild type and the inclusion body formation in the mentioned form was diminished as about 25% in comparison to the wild type. Finally, betaine had the most effects for enhancing the soluble expression of N23F in both host cells. For the wild type, sodium selenite, xylitol, and glycine showed the most effects on soluble production.

Conclusion: The solubility of the mutant form of TEV protease increased in E. coli BL21 (DE3) compared to its wild form. Also, using additives such as betaine to the lysis buffer, increased the solubility of N23F in E. coli BL21 (DE3) and origami strains.

Background: The surface properties of the materials used significantly influence the success and longevity of medical implants. Increasing surface roughness promotes osteoblast activity and osseointegration, while biodegradable materials such as copper have shown potential for antimicrobial applications. However, the effect of coating parameters on surface topography is not well investigated.

Methods: Sputtering of copper was performed using EPOS-PVD-440 system (Zeleno-grad, Russia). The samples were examined by Scanning Electron Microscopy (SEM) with subsequent image processing in Mountains software (Digital Surf). Antibacterial efficacy was evaluated against Staphylococcus aureus by measuring the zone of inhibition. Additionally, copper ion release was monitored over time to assess its correlation with changes in surface topography.

Results: Higher sputtering currents increased surface roughness and particle size, with a significant release of copper ions within the first 24 hr of immersion. Samples sputtered at higher currents exhibited coarser grain structures. The release of copper ions in the simulated biological environment led to further changes in surface topography, highlighting the critical influence of sputtering parameters on coating properties.

Conclusion: Optimizing magnetron copper deposition parameters enhances the surface topography and antibacterial effectiveness of biodegradable coatings on implants.