Hadi Sekhavati | Ferdowsi University of Mashhad (original) (raw)

Papers by Hadi Sekhavati

Journal of Poultry Sciences and Avian Diseases

This study describes the development of a cross-protective vaccine candidate against avian influe... more This study describes the development of a cross-protective vaccine candidate against avian influenza virus, which was designed using M2e, a highly preserved antigen. The consensus sequence of M2e was obtained using 31 sequences of avian influenza virus subtypes (H5N8, H5N1, H9N2, and H7N9) isolated from seven avian species in five Asian countries. An adjuvant, a partial sequence of flagellin, was also considered. Two chimeric antigens were designed and virtually cloned and expressed using the PYD1 vector and EBY100 yeast strain. Molecular dynamic simulations were used to assess the stability and conformational features of these antigens. The likelihood of detection by a specific monoclonal antibody, MAb148, was estimated for the designed peptides using docking studies. The second chimeric antigen was more compact and stable than the first design, but it was less detectable by MAb148. In the first design, two of the four desired epitopes ("SLLTEVETP") were exposed, while only a partial sequence of this epitope was detectable in the second design. In contrast to the second chimeric antigen, electrostatic, and binding energies related to the interaction of the first antigen and MAb148 were significantly closer to the positive control. This suggests that epitopes of the first chimeric antigen could be correctly located in the specific paratope of MAb148. In conclusion, the first chimeric antigen exhibits favorable conformational features and epitope-paratope interactions, highlighting its potential as a promising cross-protective vaccine candidate against a range of avian influenza virus subtypes.

Avian influenza subtype H9N2 is the most prevalent influenza virus in poultry worldwide. It impos... more Avian influenza subtype H9N2 is the most prevalent influenza virus in poultry worldwide. It imposes economic losses on the poultry industry and has zoonotic potential. Currently, there are two main groups of anti-influenza drugs in use; Adamantanes and Neuraminidase inhibitors. In recent years, there has been increasing resistance to existing anti-influenza drugs. Antimicrobial peptides are a group of potential drug candidates with broad-spectrum activity. cLF-chimera is an antimicrobial peptide synthesized from camel milk lactoferrin. This study's objective is to evaluate the inhibitory effects of cLF-chimera on avian influenza, subtype H9N2. For this purpose, one hundred and seventy 11-day-old embryonated eggs were randomly distributed in 17 groups. Different virus and peptide concentrations were injected into the eggs. The eggs were incubated for four days with daily candling for viability assessment. On the 4th day of incubation, each group's alive or dead embryos were s...

Background: Immunomodulatory peptides are capable of stimulating or suppressing the immune system... more Background: Immunomodulatory peptides are capable of stimulating or suppressing the immune system. Hence, deregulation of them can be considered as an immunotherapy approach. These peptides may have dual behavior in response to different infections. For instance, an antimicrobial peptide may act as an anticancer, tumor marker or even cause cancer progression. Methods: In this study, we used single-cell RNA sequencing analysis to investigate the deregulation of immunomodulatory peptides in malignant versus normal human breast epithelial cells. We validated the obtained results in chromatin accessibility level. Furthermore, we used a drug repositioning approach to change the expression of these peptides based on their role in cancer biology. Results: As a result, ten immunomodulatory peptides were upregulated in breast cancer versus normal. Chromatin was more accessible for these peptides in cancer cell lines versus normal. Among these ten peptides, five of them were tumor drivers (i....

Objective Brucellosis is a common disease between humans and livestock that has caused a great de... more Objective Brucellosis is a common disease between humans and livestock that has caused a great deal of damage to the livestock industry in recent years. One way to prevent this disease is to get a vaccine to immunize disease-prone herds. To produce a successful recombinant vaccine, factors such as: selecting the right adjuvant, selecting the right antigen and the right delivery system are very important. To this end, epitopes have recently been widely used in clinical research, biomedicine, and the production of recombinant vaccines. Surface proteins of this bacterium, including BLS and Omp25 proteins, have antigenic properties and play an important role in causing this disease. Due to the lack of effective vaccines, today the need to produce new and effective vaccines is felt more than ever. The aim of this study was to bioinformatically predict the epitopes of BLS and Omp25 genes of Brucella bacterium in order to introduce a suitable candidate for vaccine production. Materials and...

archives of razi institute, 2016

Brucellosis is a well-known infection in domestic animals which caused by Brucella bacterium. Due... more Brucellosis is a well-known infection in domestic animals which caused by Brucella bacterium. Due to serious economic and medical consequences of this disease, various efforts have been made to prevent the infection through the use of recombinant vaccines based on Brucella outer membrane protein (OMP) antigens. The objectives of the present study were cloning, sequencing and epitope prediction of Omp25 and BLS genes as two major Brucella melitensis antigens. The full-length open reading frame (ORF) of Omp25 and BLS genes were amplified and cloned into pTZ57R/T vector. Phylogenetic analysis of sequenced genes showed that both genes were nearly similar in different Brucella species. Several online prediction softwares were used to predict B and T-cells epitopes, secondary and tertiary structures, antigenicity ability and enzymatic degradation sites. Bioinformatic tools used in the current study were confirmed by the results of three different experimental epitope predictions. Bioinfor...

Poultry Science, 2021

Clostridium perfringens-induced necrotic enteritis (NE) is an economically important disease of b... more Clostridium perfringens-induced necrotic enteritis (NE) is an economically important disease of broiler chickens. The present study evaluated the effect of C. perfringens on the intestinal histomorphometry, enteric microbial colonization, and host immune responses using 3 experimental NE reproduction methods. The experimental groups consisted of 1) unchallenged Control diet (corn-soybean meal), 2) Control diet + Eimera inoculation at d 11 followed by C. perfringens challenge at d 15 (ECp), 3) Wheat-based diet + C. perfringens challenge (WCp), and 4) Wheat-based diet + Eimeria inoculation followed by C. perfringens challenge (WECp). The results showed that chickens receiving ECp and WECp had reduced (P < 0.05) bird performance coupled with enteric gross lesions and epithelial damage at d 17 and 24 of age compared to unchallenged control birds. These ECp and WECp administered birds also had increased (P < 0.05) ileal colonization by clostridia and E. coli at d 17 and 24, while the resident Lactobacillus counts were reduced (P < 0.05) at d 24 of age. Furthermore, at d 24, jejunal transcription of IL-6, IL-10, annexin-A1 and IL-2 genes was upregulated (P < 0.05) in the ECp group, whereas the transcription of TNF receptor associated factor (TRAF)-3 gene was increased (P < 0.05) in WECp treated birds when compared to unchallenged control group. Additionally, stimulation of chicken splenocytes and cecal tonsilocytes with virulent C. perfringens bacilli or their secretory proteins resulted in a higher (P < 0.05) frequency of T cells and their upregulation of MHC-II molecule, as determined by flow cytometry. These findings suggest that C. perfringens, while inducing epithelial damage and changes in microbiota, can also trigger host immune responses. Furthermore, NE reproduction methods using coccidia with or without the wheat-based dietary predisposition seem to facilitate an optimal NE reproduction in broiler chickens and thus, may provide better avenues for future C. perfringens research.

Archives of Razi Institute, 2018

Brucellosis is a zoonotic disease in human and animals. Brucella melitensis is one of the most pa... more Brucellosis is a zoonotic disease in human and animals. Brucella melitensis is one of the most pathogenic species of Brucella in goat and sheep. Omp31 is an outer membrane protein of Brucella that acts as an immunogenic protein. Cytokines are glycoproteins with low molecular weight that play the role of an immune adjuvant and regulate immune responses. Interleukin-2 is one of the most important cytokines, which are secreted by the white blood cells and involved in T cell immune responses. In the present study, a chimeric Omp31-Interleukin2 recombinant protein was generated by means of genetic engineering techniques. This chimeric coding sequence was amplified by using specific primers and using Splicing Overlap Extension (SOE) PCR technique. The fusion of the two mentioned proteins was accomplished using a rigid linker. The generated chimeric IL2-Omp31 fragment was TA cloned, and then subcloned into pEt22b vector as an expression vector. The chimeric protein was successfully express...

Brucellosis is a widespread zoonotic disease that still of veterinarian, public health and econom... more Brucellosis is a widespread zoonotic disease that still of veterinarian, public health and economic concern in many developing countries (Karthik et al. 2013). This disease is caused by bacteria of the genus Brucella, Gram-negative, facultative, intracellular pathogens that can infect primarily the domestic animals (Cutler and Whatmore, 2005). The main worldwide pathogenic species are Brucella abortus and Brucella melitensis, which are involved in bovine and ovine brucellosis, respectively (Corbel and BrinleyMorgan, 1984). These diseases are characterized by abortion and reduced fertility in animals and also by chronic infections with symptoms such as undulant fever, arthritis and osteomyelitis in humans (Pappas et al. 2006). Brucella outer membrane proteins (OMPs) play a critical role in stimulating host immune system. The major Brucella OMPs have been classified in two groups 1:OMP2a and OMP2b (36-38 kDa) and 2:OMP25 and OMP31 (25 kDa and 31-34 kDa) (Cloeckaert et al. 2002). OMP25...

The Canarypox virus (CNPV) infects captive and wild canaries and cause high mortality and substan... more The Canarypox virus (CNPV) infects captive and wild canaries and cause high mortality and substantial economic losses especially in Middle East countries. Currently, unapproved and illegally imports of embryo propagated, freeze-dried, and live CNPV vaccines are being used by individuals for personal uses in Iran and the region against canarypox disease. The aim of this work was to prepare the stage for the design of a peptide vaccine against canarypox disease. Two immunogenic CNPV proteins were chosen based on homology to antigens from Poxine®, HP1-440 and FP9 strains in fowlpox virus. MHC II specific epitopes of candidate proteins were characterized using various bioinformatics tools. The predicted epitopes were modeled and docked to HLA-DRB1 0101, 0301, 0401, 0405 and 1501 receptors. The stability of docked complexes was evaluated through molecular dynamic simulations. Also, an experimental epitope in vaccinia virus for MHC I receptors was chosen and its canary homolog was docked ...

Biotechnology Journal, 2021

The use of anticancer peptides (ACPs) as an alternative/complementary strategy to conventional ch... more The use of anticancer peptides (ACPs) as an alternative/complementary strategy to conventional chemotherapy treatments has been shown to decrease drug resistance and/or severe side effects. However, the efficacy of the positively‐charged ACP is inhibited by elevated levels of negatively‐charged cell‐surface components which trap the peptides and prevent their contact with the cell membrane. Consequently, this decreases ACP‐mediated membrane pore formation and cell lysis. Negatively‐charged heparan sulphate (HS) and chondroitin sulphate (CS) have been shown to inhibit the cytotoxic effect of ACPs.In this study, we propose a strategy to promote the broad utilization of ACPs. In this context, we developed a drug repositioning pipeline to analyse transcriptomics data generated for four different cancer cell lines (A549, HEPG2, HT29, and MCF7) treated with hundreds of drugs in the LINCS L1000 project. Based on previous studies identifying genes modulating levels of the glycosaminoglycans...

Scientific Reports, 2020

Three hundred and sixty 1-day-old male broiler chicks were randomly allocated to 4 treatments of ... more Three hundred and sixty 1-day-old male broiler chicks were randomly allocated to 4 treatments of 6 replicates to evaluate the effects of cLFchimera, a recombinant antimicrobial peptide (AMP), on gut health attributes of broiler chickens under necrotic enteritis (NE) challenge. Treatments were as follows: (T1) unchallenged group fed with corn-soybean meal (CSM) without NE challenge and additives (NC); (T2) group fed with CSM and challenged with NE without any additives (PC); (T3) PC group supplemented with 20 mg cLFchimera/kg diet (AMP); (T4) PC group supplemented with 45 mg antibiotic (bacitracin methylene disalicylate)/kg diet (antibiotic). Birds were sampled for villi morphology, ileal microbiota, and jejunal gene expression of cytokines, tight junctions proteins, and mucin. Results showed that AMP ameliorated NE-related intestinal lesions, reduced mortality, and rehabilitated jejunal villi morphology in NE challenged birds. While the antibiotic non-selectively reduced the count o...

Probiotics and Antimicrobial Proteins, 2020

Since Brucella infection mostly occurs through the mucosal surfaces, immune response induced by v... more Since Brucella infection mostly occurs through the mucosal surfaces, immune response induced by vaccine that is delivered by a way of mucosal route can be drastically enhanced to control the brucellosis. Omp31is the major outer membrane protein of Brucella, and is considered as a protective antigen against Brucella infection. Accordingly, Lactococcus lactis has been used as an antigen-delivering vector to develop a vaccine-induced mucosal response for having a safer vaccination against brucellosis. A designed omp31 gene fused to the usp45 signal peptide and M6 cell wall anchor was sub cloned in the pNZ7021 expression vector, and a recombinant L. lactis displaying Omp31 was constructed. Omp31 protein expression was confirmed using Western blotting and immunofluorescence analysis. Animals were orally and intraperitoneally immunized with live or killed L. lactis expressing Omp31, respectively. The humoral and cellular immune responses were evaluated by measuring the specific cytokines and antibodies. sIgA, serum IgA, IgM, and total IgG antibodies significantly increased in the mice immunized with live recombinant L. lactis expressing Omp31 and also serum IgM, and total IgG antibodies significantly increased in mice immunized with killed recombinant L. lactis expressing Omp31. Among IgG subtypes, IgG2a response was significantly higher in both groups compared to IgG1. In mice groups immunized with recombinant L. lactis, the IFN-γ and IL-10 level elevated; however, there was no change in the level of IL-4. These results indicated that recombinants L. lactis induce both humoral and cellular immune responses in mice, and also vaccines based on L. lactis-derived live carriers are promising interventions against Brucella melitensis infections.

APMIS, 2017

Abbassi-Daloii T, Yousefi S, Sekhavati MH, Tahmoorespur M. Impact of heat shock protein 60KD in c... more Abbassi-Daloii T, Yousefi S, Sekhavati MH, Tahmoorespur M. Impact of heat shock protein 60KD in combination with outer membrane proteins on immune response against Brucella melitensis. APMIS 2017. Brucellosis caused by the bacterium Brucella affects various domestic and wild species. The outer membrane proteins 25 and 31 play key roles on stimulation of cell-mediated immune response against Brucella. GroEL as one of the major Brucella antigens stimulates the immune system and increases intracellular survival of bacteria. In the present study, we assumed injection of GroEL in combination with OMP25 and OMP31 would offer higher immunity levels. So, the impact of GroEL with different concentrations of recombinant outer membrane proteins emulsified in Chitosan Nanoparticles on immune responses was evaluated in mice model. Results showed both univalent (except rGroEL) and divalent immunized groups induced higher IFN-c, TNF-a, and IL-4 titers in comparison to negative control groups. While GroEL showed negative effect on TNF-a titer, there were positive increase trends in IFN-c in some treatments. Analysis of humoral antibody response revealed both univalent and divalent immunized groups induced higher IgG2a titer than IgG1 titer, indicating strong bent of Th1 immune response. Also, results showed GroEL can have positive impact on lymphocyte proliferation response. Overall, mice immunization using individual OMP25 or OMP31 demonstrated more effective cell-mediated immunity, although some combinations of rGroEL and rOMP31 vaccines were more efficient than other divalent ones.

Journal of Clinical Oncology, 2018

10 Background: Background: Prostate Specific Antigen (PSA) is a molecular marker of prostate canc... more 10 Background: Background: Prostate Specific Antigen (PSA) is a molecular marker of prostate cancer (PC). I most countries, standard of care suggests annual PSA testing in all men over 50 years of age; and for men at high risk, the test is recommended from 40 years of age. Due to low Specificity and low sensitivity of the PSA test, a large number of unnecessary biopsies occur every year. This low specificity can be due to the fact that PSA is found in both benign and malignant lesions of Prostate tissue. To date measurement of the percentage of free PSA, have resulted an small improvements in specificity of PSA testing. Thus, the development of a simple blood test to detect prostate cancer that exhibits higher specificity compared to PSA could have the potential of reducing biopsies performed due to false positive screening results and improve the quality of medical care. Methods: We have investigated the utility of aspartyl (asparaginyl) β-hydroxylase (AABH) as a prostate cancer bi...

Journal of Clinical Oncology, 2018

86 Background: Colorectal Cancer (CRC) is the third most common type of cancer diagnosed in the U... more 86 Background: Colorectal Cancer (CRC) is the third most common type of cancer diagnosed in the US and Canada. WHO, Canadian Cancer Society (CCS), the National Comprehensive Cancer Network (NCCN) and American Cancer Society (ACS) recommend that men and women begin CRC screening at age 50 or younger if at high risk. Recommended screening procedures: Annual occult fecal blood test (OFBT), a colonoscopy every 5 years, OFBT and colonoscopy every 5 years, or a colonoscopy every 10 years. According to The Surveillance, Epidemiology, and End Results (SEER) Program, only 39% of CRC are diagnosed in stage I, 36% are diagnosed in Stage II, 19% are diagnosed with metastasis. The corresponding 5-year survival rates are 89.8%, 67.7%, and 10.3%. Neither the CCS nor the ACS recommends a blood test be done as part of screening. This is due to the fact that, until now, there has not been a blood test with adequate sensitivity or specificity for screening. Methods: In this study we discovered that As...

International Journal of Peptide Research and Therapeutics, 2020

Antimicrobial peptides (AMPs) are native and safe short peptides with valuable biological effects... more 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.

International Journal of Peptide Research and Therapeutics, 2019

In the present study, a novel chimeric peptide was derived from camel lactoferrin designed with a... more 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.

International Journal of Peptide Research and Therapeutics, 2019

Brucella is an important zoonotic pathogen which causes significant commercial loss in industry a... more Brucella is an important zoonotic pathogen which causes significant commercial loss in industry and considerable disease in livestock and human. Diminishing fertility and also abortion in animal and Malta fever disease in human. In spite of some successful vaccines against animal brucellosis, no satisfactory vaccine has been produced against human brucellosis. Accordingly, OMP31 as a major immunogenic and immunodominant protein in Brucella melitensis has been used to predict substantial epitopes against human and/or sheep MHCII alleles in three different continents (America, Oceania, and Europe) through bioinformatics tools. In order to validate region-based projections, the accuracy of epitopes was assessed by Vaxijen, an online server. The structure of these peptides was predicted through PEP-FOLD server. Predicted epitopes were sifted through docking studies with relevant MHCII receptors and finally, docked complexes were evaluated by molecular dynamic simulations. According to the frequency of human and sheep alleles in different regions, "FGTVRARLG" and "YIGINAGYA" epitopes can be considered for American, Eastern European, and Asian human populations and also sheep flocks of Australia and New Zealand (Corriedale breed), United States (Polypay and Rumbouillet breeds) and France (Rambouillet breed). Besides, "AINNNWTLKSE", "FLESKVNFH", "VLGAETDFQG", and YIGINAGYA can be significant in American and northern Indian human populations and also sheep of France (Suffolk and Columbia breeds), England and Scotland (Cheviot breed) and United States (Polypay breed). Eventually, "AINNNWTLKSE" and "VQAGYNWQL" might be important in American human and Britannia (Scottish Blackface breed), United States (Columbia, Rambouillet, and Polypay breeds) and French (Rambouillet breed) sheep populations.

Journal of Poultry Sciences and Avian Diseases

This study describes the development of a cross-protective vaccine candidate against avian influe... more This study describes the development of a cross-protective vaccine candidate against avian influenza virus, which was designed using M2e, a highly preserved antigen. The consensus sequence of M2e was obtained using 31 sequences of avian influenza virus subtypes (H5N8, H5N1, H9N2, and H7N9) isolated from seven avian species in five Asian countries. An adjuvant, a partial sequence of flagellin, was also considered. Two chimeric antigens were designed and virtually cloned and expressed using the PYD1 vector and EBY100 yeast strain. Molecular dynamic simulations were used to assess the stability and conformational features of these antigens. The likelihood of detection by a specific monoclonal antibody, MAb148, was estimated for the designed peptides using docking studies. The second chimeric antigen was more compact and stable than the first design, but it was less detectable by MAb148. In the first design, two of the four desired epitopes ("SLLTEVETP") were exposed, while only a partial sequence of this epitope was detectable in the second design. In contrast to the second chimeric antigen, electrostatic, and binding energies related to the interaction of the first antigen and MAb148 were significantly closer to the positive control. This suggests that epitopes of the first chimeric antigen could be correctly located in the specific paratope of MAb148. In conclusion, the first chimeric antigen exhibits favorable conformational features and epitope-paratope interactions, highlighting its potential as a promising cross-protective vaccine candidate against a range of avian influenza virus subtypes.

Avian influenza subtype H9N2 is the most prevalent influenza virus in poultry worldwide. It impos... more Avian influenza subtype H9N2 is the most prevalent influenza virus in poultry worldwide. It imposes economic losses on the poultry industry and has zoonotic potential. Currently, there are two main groups of anti-influenza drugs in use; Adamantanes and Neuraminidase inhibitors. In recent years, there has been increasing resistance to existing anti-influenza drugs. Antimicrobial peptides are a group of potential drug candidates with broad-spectrum activity. cLF-chimera is an antimicrobial peptide synthesized from camel milk lactoferrin. This study's objective is to evaluate the inhibitory effects of cLF-chimera on avian influenza, subtype H9N2. For this purpose, one hundred and seventy 11-day-old embryonated eggs were randomly distributed in 17 groups. Different virus and peptide concentrations were injected into the eggs. The eggs were incubated for four days with daily candling for viability assessment. On the 4th day of incubation, each group's alive or dead embryos were s...

Background: Immunomodulatory peptides are capable of stimulating or suppressing the immune system... more Background: Immunomodulatory peptides are capable of stimulating or suppressing the immune system. Hence, deregulation of them can be considered as an immunotherapy approach. These peptides may have dual behavior in response to different infections. For instance, an antimicrobial peptide may act as an anticancer, tumor marker or even cause cancer progression. Methods: In this study, we used single-cell RNA sequencing analysis to investigate the deregulation of immunomodulatory peptides in malignant versus normal human breast epithelial cells. We validated the obtained results in chromatin accessibility level. Furthermore, we used a drug repositioning approach to change the expression of these peptides based on their role in cancer biology. Results: As a result, ten immunomodulatory peptides were upregulated in breast cancer versus normal. Chromatin was more accessible for these peptides in cancer cell lines versus normal. Among these ten peptides, five of them were tumor drivers (i....

Objective Brucellosis is a common disease between humans and livestock that has caused a great de... more Objective Brucellosis is a common disease between humans and livestock that has caused a great deal of damage to the livestock industry in recent years. One way to prevent this disease is to get a vaccine to immunize disease-prone herds. To produce a successful recombinant vaccine, factors such as: selecting the right adjuvant, selecting the right antigen and the right delivery system are very important. To this end, epitopes have recently been widely used in clinical research, biomedicine, and the production of recombinant vaccines. Surface proteins of this bacterium, including BLS and Omp25 proteins, have antigenic properties and play an important role in causing this disease. Due to the lack of effective vaccines, today the need to produce new and effective vaccines is felt more than ever. The aim of this study was to bioinformatically predict the epitopes of BLS and Omp25 genes of Brucella bacterium in order to introduce a suitable candidate for vaccine production. Materials and...

archives of razi institute, 2016

Brucellosis is a well-known infection in domestic animals which caused by Brucella bacterium. Due... more Brucellosis is a well-known infection in domestic animals which caused by Brucella bacterium. Due to serious economic and medical consequences of this disease, various efforts have been made to prevent the infection through the use of recombinant vaccines based on Brucella outer membrane protein (OMP) antigens. The objectives of the present study were cloning, sequencing and epitope prediction of Omp25 and BLS genes as two major Brucella melitensis antigens. The full-length open reading frame (ORF) of Omp25 and BLS genes were amplified and cloned into pTZ57R/T vector. Phylogenetic analysis of sequenced genes showed that both genes were nearly similar in different Brucella species. Several online prediction softwares were used to predict B and T-cells epitopes, secondary and tertiary structures, antigenicity ability and enzymatic degradation sites. Bioinformatic tools used in the current study were confirmed by the results of three different experimental epitope predictions. Bioinfor...

Poultry Science, 2021

Clostridium perfringens-induced necrotic enteritis (NE) is an economically important disease of b... more Clostridium perfringens-induced necrotic enteritis (NE) is an economically important disease of broiler chickens. The present study evaluated the effect of C. perfringens on the intestinal histomorphometry, enteric microbial colonization, and host immune responses using 3 experimental NE reproduction methods. The experimental groups consisted of 1) unchallenged Control diet (corn-soybean meal), 2) Control diet + Eimera inoculation at d 11 followed by C. perfringens challenge at d 15 (ECp), 3) Wheat-based diet + C. perfringens challenge (WCp), and 4) Wheat-based diet + Eimeria inoculation followed by C. perfringens challenge (WECp). The results showed that chickens receiving ECp and WECp had reduced (P < 0.05) bird performance coupled with enteric gross lesions and epithelial damage at d 17 and 24 of age compared to unchallenged control birds. These ECp and WECp administered birds also had increased (P < 0.05) ileal colonization by clostridia and E. coli at d 17 and 24, while the resident Lactobacillus counts were reduced (P < 0.05) at d 24 of age. Furthermore, at d 24, jejunal transcription of IL-6, IL-10, annexin-A1 and IL-2 genes was upregulated (P < 0.05) in the ECp group, whereas the transcription of TNF receptor associated factor (TRAF)-3 gene was increased (P < 0.05) in WECp treated birds when compared to unchallenged control group. Additionally, stimulation of chicken splenocytes and cecal tonsilocytes with virulent C. perfringens bacilli or their secretory proteins resulted in a higher (P < 0.05) frequency of T cells and their upregulation of MHC-II molecule, as determined by flow cytometry. These findings suggest that C. perfringens, while inducing epithelial damage and changes in microbiota, can also trigger host immune responses. Furthermore, NE reproduction methods using coccidia with or without the wheat-based dietary predisposition seem to facilitate an optimal NE reproduction in broiler chickens and thus, may provide better avenues for future C. perfringens research.

Archives of Razi Institute, 2018

Brucellosis is a zoonotic disease in human and animals. Brucella melitensis is one of the most pa... more Brucellosis is a zoonotic disease in human and animals. Brucella melitensis is one of the most pathogenic species of Brucella in goat and sheep. Omp31 is an outer membrane protein of Brucella that acts as an immunogenic protein. Cytokines are glycoproteins with low molecular weight that play the role of an immune adjuvant and regulate immune responses. Interleukin-2 is one of the most important cytokines, which are secreted by the white blood cells and involved in T cell immune responses. In the present study, a chimeric Omp31-Interleukin2 recombinant protein was generated by means of genetic engineering techniques. This chimeric coding sequence was amplified by using specific primers and using Splicing Overlap Extension (SOE) PCR technique. The fusion of the two mentioned proteins was accomplished using a rigid linker. The generated chimeric IL2-Omp31 fragment was TA cloned, and then subcloned into pEt22b vector as an expression vector. The chimeric protein was successfully express...

Brucellosis is a widespread zoonotic disease that still of veterinarian, public health and econom... more Brucellosis is a widespread zoonotic disease that still of veterinarian, public health and economic concern in many developing countries (Karthik et al. 2013). This disease is caused by bacteria of the genus Brucella, Gram-negative, facultative, intracellular pathogens that can infect primarily the domestic animals (Cutler and Whatmore, 2005). The main worldwide pathogenic species are Brucella abortus and Brucella melitensis, which are involved in bovine and ovine brucellosis, respectively (Corbel and BrinleyMorgan, 1984). These diseases are characterized by abortion and reduced fertility in animals and also by chronic infections with symptoms such as undulant fever, arthritis and osteomyelitis in humans (Pappas et al. 2006). Brucella outer membrane proteins (OMPs) play a critical role in stimulating host immune system. The major Brucella OMPs have been classified in two groups 1:OMP2a and OMP2b (36-38 kDa) and 2:OMP25 and OMP31 (25 kDa and 31-34 kDa) (Cloeckaert et al. 2002). OMP25...

The Canarypox virus (CNPV) infects captive and wild canaries and cause high mortality and substan... more The Canarypox virus (CNPV) infects captive and wild canaries and cause high mortality and substantial economic losses especially in Middle East countries. Currently, unapproved and illegally imports of embryo propagated, freeze-dried, and live CNPV vaccines are being used by individuals for personal uses in Iran and the region against canarypox disease. The aim of this work was to prepare the stage for the design of a peptide vaccine against canarypox disease. Two immunogenic CNPV proteins were chosen based on homology to antigens from Poxine®, HP1-440 and FP9 strains in fowlpox virus. MHC II specific epitopes of candidate proteins were characterized using various bioinformatics tools. The predicted epitopes were modeled and docked to HLA-DRB1 0101, 0301, 0401, 0405 and 1501 receptors. The stability of docked complexes was evaluated through molecular dynamic simulations. Also, an experimental epitope in vaccinia virus for MHC I receptors was chosen and its canary homolog was docked ...

Biotechnology Journal, 2021

The use of anticancer peptides (ACPs) as an alternative/complementary strategy to conventional ch... more The use of anticancer peptides (ACPs) as an alternative/complementary strategy to conventional chemotherapy treatments has been shown to decrease drug resistance and/or severe side effects. However, the efficacy of the positively‐charged ACP is inhibited by elevated levels of negatively‐charged cell‐surface components which trap the peptides and prevent their contact with the cell membrane. Consequently, this decreases ACP‐mediated membrane pore formation and cell lysis. Negatively‐charged heparan sulphate (HS) and chondroitin sulphate (CS) have been shown to inhibit the cytotoxic effect of ACPs.In this study, we propose a strategy to promote the broad utilization of ACPs. In this context, we developed a drug repositioning pipeline to analyse transcriptomics data generated for four different cancer cell lines (A549, HEPG2, HT29, and MCF7) treated with hundreds of drugs in the LINCS L1000 project. Based on previous studies identifying genes modulating levels of the glycosaminoglycans...

Scientific Reports, 2020

Three hundred and sixty 1-day-old male broiler chicks were randomly allocated to 4 treatments of ... more Three hundred and sixty 1-day-old male broiler chicks were randomly allocated to 4 treatments of 6 replicates to evaluate the effects of cLFchimera, a recombinant antimicrobial peptide (AMP), on gut health attributes of broiler chickens under necrotic enteritis (NE) challenge. Treatments were as follows: (T1) unchallenged group fed with corn-soybean meal (CSM) without NE challenge and additives (NC); (T2) group fed with CSM and challenged with NE without any additives (PC); (T3) PC group supplemented with 20 mg cLFchimera/kg diet (AMP); (T4) PC group supplemented with 45 mg antibiotic (bacitracin methylene disalicylate)/kg diet (antibiotic). Birds were sampled for villi morphology, ileal microbiota, and jejunal gene expression of cytokines, tight junctions proteins, and mucin. Results showed that AMP ameliorated NE-related intestinal lesions, reduced mortality, and rehabilitated jejunal villi morphology in NE challenged birds. While the antibiotic non-selectively reduced the count o...

Probiotics and Antimicrobial Proteins, 2020

Since Brucella infection mostly occurs through the mucosal surfaces, immune response induced by v... more Since Brucella infection mostly occurs through the mucosal surfaces, immune response induced by vaccine that is delivered by a way of mucosal route can be drastically enhanced to control the brucellosis. Omp31is the major outer membrane protein of Brucella, and is considered as a protective antigen against Brucella infection. Accordingly, Lactococcus lactis has been used as an antigen-delivering vector to develop a vaccine-induced mucosal response for having a safer vaccination against brucellosis. A designed omp31 gene fused to the usp45 signal peptide and M6 cell wall anchor was sub cloned in the pNZ7021 expression vector, and a recombinant L. lactis displaying Omp31 was constructed. Omp31 protein expression was confirmed using Western blotting and immunofluorescence analysis. Animals were orally and intraperitoneally immunized with live or killed L. lactis expressing Omp31, respectively. The humoral and cellular immune responses were evaluated by measuring the specific cytokines and antibodies. sIgA, serum IgA, IgM, and total IgG antibodies significantly increased in the mice immunized with live recombinant L. lactis expressing Omp31 and also serum IgM, and total IgG antibodies significantly increased in mice immunized with killed recombinant L. lactis expressing Omp31. Among IgG subtypes, IgG2a response was significantly higher in both groups compared to IgG1. In mice groups immunized with recombinant L. lactis, the IFN-γ and IL-10 level elevated; however, there was no change in the level of IL-4. These results indicated that recombinants L. lactis induce both humoral and cellular immune responses in mice, and also vaccines based on L. lactis-derived live carriers are promising interventions against Brucella melitensis infections.

APMIS, 2017

Abbassi-Daloii T, Yousefi S, Sekhavati MH, Tahmoorespur M. Impact of heat shock protein 60KD in c... more Abbassi-Daloii T, Yousefi S, Sekhavati MH, Tahmoorespur M. Impact of heat shock protein 60KD in combination with outer membrane proteins on immune response against Brucella melitensis. APMIS 2017. Brucellosis caused by the bacterium Brucella affects various domestic and wild species. The outer membrane proteins 25 and 31 play key roles on stimulation of cell-mediated immune response against Brucella. GroEL as one of the major Brucella antigens stimulates the immune system and increases intracellular survival of bacteria. In the present study, we assumed injection of GroEL in combination with OMP25 and OMP31 would offer higher immunity levels. So, the impact of GroEL with different concentrations of recombinant outer membrane proteins emulsified in Chitosan Nanoparticles on immune responses was evaluated in mice model. Results showed both univalent (except rGroEL) and divalent immunized groups induced higher IFN-c, TNF-a, and IL-4 titers in comparison to negative control groups. While GroEL showed negative effect on TNF-a titer, there were positive increase trends in IFN-c in some treatments. Analysis of humoral antibody response revealed both univalent and divalent immunized groups induced higher IgG2a titer than IgG1 titer, indicating strong bent of Th1 immune response. Also, results showed GroEL can have positive impact on lymphocyte proliferation response. Overall, mice immunization using individual OMP25 or OMP31 demonstrated more effective cell-mediated immunity, although some combinations of rGroEL and rOMP31 vaccines were more efficient than other divalent ones.

Journal of Clinical Oncology, 2018

10 Background: Background: Prostate Specific Antigen (PSA) is a molecular marker of prostate canc... more 10 Background: Background: Prostate Specific Antigen (PSA) is a molecular marker of prostate cancer (PC). I most countries, standard of care suggests annual PSA testing in all men over 50 years of age; and for men at high risk, the test is recommended from 40 years of age. Due to low Specificity and low sensitivity of the PSA test, a large number of unnecessary biopsies occur every year. This low specificity can be due to the fact that PSA is found in both benign and malignant lesions of Prostate tissue. To date measurement of the percentage of free PSA, have resulted an small improvements in specificity of PSA testing. Thus, the development of a simple blood test to detect prostate cancer that exhibits higher specificity compared to PSA could have the potential of reducing biopsies performed due to false positive screening results and improve the quality of medical care. Methods: We have investigated the utility of aspartyl (asparaginyl) β-hydroxylase (AABH) as a prostate cancer bi...

Journal of Clinical Oncology, 2018

86 Background: Colorectal Cancer (CRC) is the third most common type of cancer diagnosed in the U... more 86 Background: Colorectal Cancer (CRC) is the third most common type of cancer diagnosed in the US and Canada. WHO, Canadian Cancer Society (CCS), the National Comprehensive Cancer Network (NCCN) and American Cancer Society (ACS) recommend that men and women begin CRC screening at age 50 or younger if at high risk. Recommended screening procedures: Annual occult fecal blood test (OFBT), a colonoscopy every 5 years, OFBT and colonoscopy every 5 years, or a colonoscopy every 10 years. According to The Surveillance, Epidemiology, and End Results (SEER) Program, only 39% of CRC are diagnosed in stage I, 36% are diagnosed in Stage II, 19% are diagnosed with metastasis. The corresponding 5-year survival rates are 89.8%, 67.7%, and 10.3%. Neither the CCS nor the ACS recommends a blood test be done as part of screening. This is due to the fact that, until now, there has not been a blood test with adequate sensitivity or specificity for screening. Methods: In this study we discovered that As...

International Journal of Peptide Research and Therapeutics, 2020

Antimicrobial peptides (AMPs) are native and safe short peptides with valuable biological effects... more 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.

International Journal of Peptide Research and Therapeutics, 2019

In the present study, a novel chimeric peptide was derived from camel lactoferrin designed with a... more 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.

International Journal of Peptide Research and Therapeutics, 2019

Brucella is an important zoonotic pathogen which causes significant commercial loss in industry a... more Brucella is an important zoonotic pathogen which causes significant commercial loss in industry and considerable disease in livestock and human. Diminishing fertility and also abortion in animal and Malta fever disease in human. In spite of some successful vaccines against animal brucellosis, no satisfactory vaccine has been produced against human brucellosis. Accordingly, OMP31 as a major immunogenic and immunodominant protein in Brucella melitensis has been used to predict substantial epitopes against human and/or sheep MHCII alleles in three different continents (America, Oceania, and Europe) through bioinformatics tools. In order to validate region-based projections, the accuracy of epitopes was assessed by Vaxijen, an online server. The structure of these peptides was predicted through PEP-FOLD server. Predicted epitopes were sifted through docking studies with relevant MHCII receptors and finally, docked complexes were evaluated by molecular dynamic simulations. According to the frequency of human and sheep alleles in different regions, "FGTVRARLG" and "YIGINAGYA" epitopes can be considered for American, Eastern European, and Asian human populations and also sheep flocks of Australia and New Zealand (Corriedale breed), United States (Polypay and Rumbouillet breeds) and France (Rambouillet breed). Besides, "AINNNWTLKSE", "FLESKVNFH", "VLGAETDFQG", and YIGINAGYA can be significant in American and northern Indian human populations and also sheep of France (Suffolk and Columbia breeds), England and Scotland (Cheviot breed) and United States (Polypay breed). Eventually, "AINNNWTLKSE" and "VQAGYNWQL" might be important in American human and Britannia (Scottish Blackface breed), United States (Columbia, Rambouillet, and Polypay breeds) and French (Rambouillet breed) sheep populations.