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27 result(s) for "Tahmoorespur, Mojtaba"
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Interaction of camel Lactoferrin derived peptides with DNA: a molecular dynamics study
Background Lactoferrampin (LFampin), Lactoferricin (LFcin), and LFchimera are three well-known antimicrobial peptides derived from Lactoferrin and proposed as alternatives for antibiotics. Although the intracellular activity of these peptides has been previously demonstrated, their mode of action is not yet fully understood. Here, we performed a molecular dynamics simulation study to understand the molecular interactions between camel Lactoferrin derived peptides, including CLFampin, CLFcin, and CLFchimera, and DNA as an important intracellular target. Results Our results indicate that all three peptides bind to DNA, albeit with different propensities, with CLFchimera showing the highest binding affinity. The secondary structures of the peptides, modeled on Lactoferrin, did not undergo significant changes during simulation, supporting their functional relevance. Main residues involved in the peptide-DNA interaction were identified based on binding free energy estimates calculated over 200 ns, which, as expected, confirmed strong electrostatic interactions between DNA phosphate groups and positively charged peptide side chains. Interaction between the different concentrations of CLFchimera and DNA revealed that after binding of four copies of CLFchimera to DNA, hydrogen bonds between the two strands of DNA start to break from one of the termini. Conclusions Importantly, our results revealed that there is no DNA-sequence preference for peptide binding, in line with a broad antimicrobial activity. Moreover, the results showed that the strength of the interaction between DNA and CLFchimera is concentration dependent. The insight provided by these results can be used for the rational redesign of natural antimicrobial peptides targeting the bacterial DNA.
The immunomodulatory effects of lactoferrin and its derived peptides on NF‐κB signaling pathway: A systematic review and meta‐analysis
Background Lactoferrin is a versatile protein with important modulatory functions in inflammation and immune response. This glycoprotein can bind and sequester iron and LPS, thereby intervening in certain signaling pathways and biological processes. In the present meta‐analysis, we aimed to pool experimental data regarding the immunomodulatory effects of lactoferrin and its derived peptides on the NF‐κB signaling pathway. Materials We searched PubMed, Google Scholar, and Web of Science databases and obtained all related articles published before April 2022. Finally, 25 eligible studies were selected, and their reports were analyzed. Methods We used Review Manager Version 5.2 to compute the standardized mean difference (SMD) and its 95% confidence interval. In addition, the source of heterogeneity was explored using meta‐regression and sensitivity analysis. The symmetry of the funnel plot and Egger's test were also used to evaluate publication bias utilizing Comprehensive Meta‐Analysis Version 2. Results Comparing the group of cells and animals exposed to lipopolysaccharide alone with the group that received pretreatment with lactoferrin and its derivatives, we observed significant reductions in TNF‐α, IL‐1 beta, and IL‐6 levels by 8.73 pg/mL, 2.21 pg/mL, and 3.24 pg/mL, respectively, in the second group. Additionally, IKK‐β, p‐IκB, and NF‐κB (p65) levels were significantly lower by 7.37‐fold, 15.02‐fold, and 3.88‐fold, respectively, in various cells and tissues. Conclusion Based on the results of this meta‐analysis, lactoferrin and its derived peptides can be considered potent prophylactic and therapeutic candidates against inflammation‐associated diseases by targeting the NF‐kB pathway. This study is a meta‐analysis with the aim of systematic review of reported data to clarify the Immunomodulatory effects of lactoferrin and its derived peptides on NF‐κB signaling pathway. This meta‐analysis discovered that lactoferrin and its derivative peptides may have role of the modulators and Anti‐Inflammatory of immune processes by inhibitory effect on the TNF‐α, IL‐1β, and IL‐6 cytokines in upstream and IKK‐β, p‐IκB, and NF‐κB‐p65 in downstream of the NF‐κB signaling pathway.
Computational Peptide Engineering Approach for Selection the Best Engendered Camel Lactoferrin-Derive Peptide with Potency to Interact with DNA
Antimicrobial peptides (AMPs) are native and safe short peptides with valuable biological effects. Nowadays, these components and their importance have attracted the attention of many researchers to determine their mode of action. Computational peptide engineering can donate a useful insight for investigating the stability and potency of AMPs. In the present study, to improve the effect of CLF36, a chimeric peptide derived camel lactoferrin, the atomic insight into peptide-DNA interaction was analyzed using MD simulation. Targeted mutants were performed in wild type amino acid sequences and obtained engineered peptides were homology modeled for peptide-DNA interaction analysis. SASA, Hydrogen binding and free binding energy analyses revealed that all changes in wild type of peptide in this study improved the peptide-DNA interaction. Our in silico results showed that simultaneous substitution of GLU12 with ALA and also removing SER36 in wild type had more substantial effects on complex formation with DNA. The obtained result of this study could be useful to improve the stability and potency of engineered peptides to use of in the experimental study.
A Novel Chimeric Anti-HCV Peptide Derived from Camel Lactoferrin and Molecular Level Insight on Its Interaction with E2
In the present study, a novel chimeric peptide was derived from camel lactoferrin designed with a considerable anti-HCV activity and its neutralization mechanism was predicted by molecular modelling tools. A novel anti-HCV peptide derived from camel lactoferrin (cLF36) was designed and expressed it recombinantly in HEK-293-T cells. Anti-viral activity of this peptide was evaluated against hepatitis C virus by Real-time PCR assay in vitro. Finally, to have a better insight into the mode of action of peptide on HCV entry inhibition, we examined the interaction of cLF36 with envelope glycoprotein E2 by molecular dynamic simulation. This chimeric peptide had significant inhibitory effects on both HCV entry (44 µg/mL) and viral replication (88 µg/mL) under in vitro (p > 0.01). Moreover, cLF36 peptide was not toxic to HEK cells as a normal cell at twofold of its anti-viral concentrations for HCV entry and even at concentrations as high as 250 µg/mL exhibited minimal hemolysis (2.5%) against human RBCs (red blood cells). The results of in silico analysis showed that cLF36 interacted with β-sandwich and front layer of E2 protein as two potential CD81 binding sites. We generated and characterized a new camel lactoferrin derived HCV inhibitors. This peptide blocked HCV entry and also intracellular HCV replication in cell culture experiment.
In vivo immunogenicity assessment and vaccine efficacy evaluation of a chimeric tandem repeat of epitopic region of OMP31 antigen fused to interleukin 2 (IL-2) against Brucella melitensis in BALB/c mice
Background Designing a potent recombinant vaccine, using the appropriate subunits with the greatest effect on stimulating the immune system, especially in the case of intracellular pathogens such as gram negative Brucella Melitensis bacteria, is of great importance. In this study, three repeats of 27 amino acids of the immunogenic epitope derived from OMP31 antigen (3E) from the Brucella melitensis , in a protective manner against Brucellosis have been used. To fortify the delivery system of recombinant antigens, IL-2 cytokine as a molecular adjuvant was fused to recombinant constructs. Recombinant proteins were evaluated for immunological studies in a mouse model (BALB/c). Results The results showed that all recombinant proteins could stimulate the immune system to produce Th1 cytokines and antibodies in compare to the negative control treatments. 3E-IL2 and then OMP31-IL2 proteins stimulated higher levels of IFN-γ and IL-2 compared to the other treatments ( p  < 0.05). Also, the results indicated that experimental treatments produced a higher level of IgG2a isotype than IgG1 isotype. In addition, the findings of the experiment showed that the presence of chemical adjuvant (IFA) along with molecular adjuvant can play a significant role in stimulating the immune system. After determining the potency of recombinant structures, their efficacy in stimulating the immune system were also evaluated. B. melitensis M16 strain was used to challenge 30 days after last immunization. The microbial load of the splenocyte in the treatments receiving chimeric proteins were significantly lower. Also, Wright serological test confirmed that these treatments had the lowest agglutination rate, as well as the positive treatment, while in the negative treatments in excess of blood serum dilutions, agglutination rate were more than 2 + . Conclusions 3E-IL2 treatment showed the best performance compared to other recombinant proteins and could be considered as the suitable candidate for further research on the production of recombinant vaccine against Brucella.
Gene expression profile analysis of residual feed intake for Isfahan native chickens using RNA-SEQ data
The factors that affect residual feed intake (RFI) of two chicken breeds (Ross as commercial and Isfahan as Iranian local breed with low and high RFI, respectively) were examined. We sequenced their liver transcriptomes using RNA-Seq while focusing on the identification of important candidate genes, which might influence RFI and growth rate. The differential gene expression analysis revealed that 121 and 279 known genes were significantly up- and down-regulated in the local breed, respectively. QTL enrichment analysis revealed that 63 down-regulated genes in the local breed were enriched in the QTL regions related to feed efficiency traits. Moreover, the functional enrichment analysis showed that the down-regulated genes in the native chickens were mainly involved in the different metabolic processes, such as carboxylic acid metabolic process and response to stress. The Differentially Expressed Genes explored between the chickens of the two breeds led to the identification of some important candidate genes for further breed improvement programmes, including RSAD2, IL15, LIPI, EGR1 and DUSP16. These findings will be a useful resource for the biological investigations of RFI-related genes in Isfahan local chickens and may provide some clues for understanding the molecular genetic mechanisms in other chicken breeds. highlights A global view of transcriptome differences in the liver tissues of commercial and local chicken breeds with different RFI values is obtained. This investigation will contribute to the improvement of chicken genome annotation through the identification of novel transcripts and novel gene. Some important candidate genes related to RFI is obtained.
Drug repositioning for immunotherapy in breast cancer using single-cell analysis
AbstractImmunomodulatory peptides, while exhibiting potential antimicrobial, antifungal, and/or antiviral properties, can play a role in stimulating or suppressing the immune system, especially in pathological conditions like breast cancer (BC). Thus, deregulation of these peptides may serve as an immunotherapeutic strategy to enhance the immune response. In this meta-analysis, we utilized single-cell RNA sequencing data and known therapeutic peptides to investigate the deregulation of these peptides in malignant versus normal human breast epithelial cells. We corroborated our findings at the chromatin level using ATAC-seq. Additionally, we assessed the protein levels in various BC cell lines. Moreover, our in-house drug repositioning approach was employed to identify potential drugs that could positively impact the relapse-free survival of BC patients. Considering significantly deregulated therapeutic peptides and their role in BC pathology, our approach aims to downregulate B2M and SLPI, while upregulating PIGR, DEFB1, LTF, CLU, S100A7, and SCGB2A1 in BC epithelial cells through our drug repositioning pipeline. Leveraging the LINCS L1000 database, we propose BRD-A06641369 for B2M downregulation and ST-4070043 and BRD-K97926541 for SLPI downregulation without negatively affecting the MHC complex as a significantly correlated pathway with these two genes. Furthermore, we have compiled a comprehensive list of drugs for the upregulation of other selected immunomodulatory peptides. Employing an immunotherapeutic approach by integrating our drug repositioning pipeline with single-cell analysis, we proposed potential drugs and drug targets to fortify the immune system against BC.
Immunogenicity evaluation of plasmids encoding Brucella melitensis Omp25 and Omp31 antigens in BALB/c mice
Vaccination is one of the most effective means to protect humans and animals against brucellosis. Live attenuated Brucella vaccines are considered effective in animals but they may be potentially infectious to humans, so it is vital to improve the immunoprotective effects and safety of vaccines against Brucella. This study was designed to evaluate the immunogenicity of DNA vaccines encoding outer membrane proteins (Omp25 and Omp31) against Rev1 in a mouse model. For this propose, Omp25 and Omp31 genes were cloned (individually and together) into the eukaryotic expression vector pcDNA3.1/Hygro (+). Expressions of recombinant plasmids were confirmed by SDS-PAGE and Western blot analysis. Six groups of BALB/c mice (seven mice per group) were intramuscularly injected with three recombinant constructs, native pcDNA3.1/Hygro (+) and phosphate-buffered saline (PBS) as controls and subcutaneous injection of attenuated live vaccine Rev1. Results indicated that DNA vaccine immunized BALB/c mice had a dominant immunoglobulin G response and elicited a T-cell-proliferative response and induced significant levels of interferon gamma (INF-γ) compared to the control groups. Collectively, these finding suggested that the pcDNA3.1/Hygro DNA vaccines encoding Omp25 and Omp31 genes and divalent plasmid were able to induce both humoral and cellular immunity, and had the potential to be a vaccine candidate for prevention of infections.
Dynamics of The Expression of Pluripotency and Lineage Specific Genes in The Pre and Peri-Implantation Goat Embryo
Two critical points of early development are the first and second lineage segregations, which are regulated by a wide spectrum of molecular and cellular factors. Gene regulatory networks, are one of the important components which handle inner cell mass (ICM) and trophectoderm (TE) fates and the pluripotency status across different mammalian species. Considering the importance of goats in agriculture and biotechnology, this study set out to investigate the dynamics of expression of the core pluripotency markers at the mRNA and protein levels. In this experimental study, the expression pattern of three pluripotency markers ( , and ) and the linage specific markers ( , and ) were quantitatively assessed in matured (MII) oocytes and embryos at three distinctive stages: 8-16 cell stage, day-7 (D7) blastocysts and D14 blastocysts. Moreover, expression of , , proteins, and their localization in the goat blastocyst was observed through immunocytochemistry. Relative levels of mRNA transcripts for Nanog and in D3 (8-16 cell) embryos were significantly higher than D7 blastocysts and mature oocytes, while was only significantly higher than D7 blastocysts. However, the expression pattern of , as an epiblast linage marker, decreased from the oocyte to the D14 stage. The expression pattern of and , as extra embryonic linage markers, also showed a similar trend from oocyte to D3 while their expressions were up-regulated in D14 blastocysts. Reduction in , , mRNA transcription and a late increase in extra embryonic linage markers suggests that the developmental program of linage differentiation is retarded in goat embryos compared to previously reported data on mice and humans. This is likely related to late the implantation in goats.
Effect of IL-2 co-expressed or co-inoculated with immuno-dominant epitopes from VP1 protein of FMD virus on immune responses in BALB/c mice
The results of studies on vaccine development for foot-and-mouth disease (FMD) virus show that the use of inactivated vaccines for FMD virus is not completely effective. Novel vaccinations based on immuno-dominant epitopes have been shown to induce immune responses. Furthermore, for safety of immunization, access to efficient adjuvants against FMD virus seems to be critical. In this study, we produced epitope recombinant vaccines from the VP1 protein of the FMD virus for serotype O of Iran. Constructs were included polytope (tandem-repeat multiple-epitope), polytope coupled with interleukin-2 (polytope-IL 2) as a molecular adjuvant and IL-2. Three expression vectors were constructed and expressed in BL21 (DE3). To evaluate whether these recombinant vaccines induce immune responses, BALB/c mice were injected with the recombinant vaccines and their immune responses were compared with a negative control group. The humoral and cellular immune responses were measured by ELISA. The results showed that IL-2 co-expressed or co-inoculated with Polytope protein enhances the immune effect of multiple epitope recombinant vaccine against FMD virus. The results of total immunoglobulin G (IgG), IgG1, and IgG2a levels and secretion of interferon gamma (IFN-γ), IL-4 and IL-10 revealed that there were significant differences between negative control group and other injected mice with the recombinant vaccines ( 0.05). Observations indicated that the epitope recombinant plasmid of the VP1 protein co-expressed or co-inoculated with IL-2 was effective in inducing an enhanced immune response. Therefore, IL-2 can be recommended as a potential adjuvant for epitope recombinant vaccine of the VP1 protein from FMD virus.