The Effects of Mesenchymal Stem Cells Loaded with Oncolytic Coxsackievirus A21 on Mouse Models of Colorectal Cancer.

BACKGROUND: Cancer is a major cause of death worldwide. Colorectal cancer is the second most common type. Additional treatments like chemotherapy and radiation therapy may be recommended. Developing new techniques is vital due to drug resistance and a lack of targeted therapies. OBJECTIVE: In this study, the effects of mesenchymal stem cells (MSCs) loaded with oncolytic Coxsackievirus A21 (CVA21) on a mouse model of CRC were investigated. METHODS: The therapeutic potency of MSCs loaded with oncolytic CVA21 was evaluated in an experimental mouse model of colorectal cancer which received an injection CT26 cells per mouse subcutaneously. Splenocyte proliferation index, lactate dehydrogenase (LDH) assay, nitric oxide (NO) production assessment, and cytokine assay (IFN-γ, IL-4, IL-10, and TGF-ß) in the splenocyte supernatant were all used to evaluate the impact of MSCs loaded with CVA21. RESULTS: The results of this study showed that the treatment of a mouse model of colorectal cancer with MSCs loaded with oncolytic CVA21 could significantly suppress the tumor growth, which was accompanied by stimulation of splenocytes proliferation index, an increase of NO and LDH. Also, MSCs loaded with oncolytic CVA21 increased the secretion of IFN-γ and decreased the secretion of IL-4, IL-10, and TGF-ß. CONCLUSION: The results of the current study suggest that MSCs loaded with oncolytic CVA21 therapy for the CRC mouse model may have some potential advantages. On the other hand, the results of the study showed that, in addition to activating the acquired immune system, the use of MSCs loaded with oncolytic CVA21 also stimulates the innate immune system by increasing levels of nitric oxide.

Evaluation of the in vitro and in vivo efficiency of in-feed bacteriophage cocktail application to control Salmonella Typhimurium and Salmonella Enteritidis infection in broiler chicks.

RESEARCH HIGHLIGHTS: Bacteriophage (BP) cocktail was partially resistant to different temperatures and pH values.The BP cocktail showed lytic effects on different Salmonella isolates.The BP cocktail reduced Salmonella colonization in the internal organs of broilers.

Role of Long Non-coding RNA HSD17B3-AS1 in Trauma for COVID-19.

COVID-19, an acute respiratory syndrome caused by the SARS-CoV-2 virus, was first reported in late 2019 in Wuhan, China, and rapidly escalated into a global pandemic. The condition can lead to organ dysfunction and ultimately death through its onset of acute respiratory distress syndrome (ARDS). Disease severity has been linked to proinflammatory cytokines which activate the NF-κB and STAT transcription factors in infected cells. It has been proven that lncRNAs play a very important role in reducing or increasing inflammatory factors. This makes them potentially valuable in recognizing pathogenesis pathways and therapeutic targets in COVID-19. Nanocurcumin is known as an antioxidant, tumor suppressor and anti-inflammatory substance, and it can be effective to reduce inflammation caused by the disease of COVID-19. This study analyzed Sequence Read Archive data from COVID-19 patients with acute versus milder symptoms, identifying dysregulated genes and non-coding RNAs. To verify this correlation, the expression of the candidate gene was evaluated with quantitative polymerase chain reaction (qPCR) in mouse models, while immunoglobulin (Ig) G titer was measured using enzyme-linked immunosorbent assay (ELISA) in mouse serum samples. Here we introduced a novel lncRNA called HSD17B3-AS1, suggested as a therapeutic target in COVID-19 patients with acute symptoms. Furthermore, we revealed nanocurcumin is reducing the expression of HSD17B3-AS1 which leads to reduced inflammation in mice. These results suggest that HSD17B3-AS1 plays a significant regulatory role in managing COVID-19, and the downregulation of HSD17B3-AS1 by Nanocurcumin presents a promising treatment option for minimizing complications in COVID-19 patients.

New role of bacteriophages in medical oncology.

Targeted treatment of cancer is one of the most paramount approaches in cancer treatment. Despite significant advances in cancer diagnosis and treatment methods, there are still significant limitations and disadvantages in the field, including high costs, toxicity, and unwanted damage to healthy cells. The phage display technique is an innovative method for designing carriers containing exogenic peptides with cancer diagnostic and therapeutic properties. Bacteriophages possess unique properties making them effective in cancer treatment. These characteristics include the small size enabling them to penetrate vessels; having no pathogenicity to mammals; easy manipulation of their genetic information and surface proteins to introduce vaccines and drugs to cancer tissues; lower cost of large-scale production; and greater stimulation of the immune system. Bacteriophages will certainly play a more effective role in the future of medical oncology; however, studies are in the early stages of conception and require more extensive research. We aimed in this review to provide some related examples and bring insights into the potential of phages as targeted vectors for use in cancer diagnosis and treatment, especially regarding their capability in gene and drug delivery to cancer target cells, determination of tumor markers, and vaccine design to stimulate anticancer immunity.

Antiproliferative effects of mesenchymal stem cells carrying Newcastle disease virus and Lactobacillus Casei extract on CT26 Cell line: synergistic effects in cancer therapy.

BACKGROUND AND AIMS: Colorectal Cancer (CRC) is a frequent malignancy with a high mortality rate. Specific inherited and environmental influences can affect CRC. Oncolytic viruses and bacteria in treating CRC are one of the innovative therapeutic options. This study aims to determine whether mesenchymal stem cells (MSCs) infected with the Newcastle Disease Virus (NDV) in combination with Lactobacillus casei extract (L. casei) have a synergistic effects on CRC cell line growth. MATERIALS AND METHODS: MSCs taken from the bone marrow of BALB/c mice and were infected with the 20 MOI of NDV. Then, using the CT26 cell line in various groups as a single and combined treatment, the anticancer potential of MSCs containing the NDV and L. casei extract was examined. The evaluations considered the CT26 survival and the rate at which LDH, ROS, and levels of caspases eight and nine were produced following various treatments. RESULTS: NDV, MSCs-NDV, and L. casei in alone or combined treatment significantly increased apoptosis percent, LDH, and ROS production compared with the control group (P˂0.05). Also, NDV, in free or capsulated in MSCs, had anticancer effects, but in capsulated form, it had a delay compared with free NDV. The findings proved that L. casei primarily stimulates the extrinsic pathway, while NDV therapy promotes apoptosis through the activation of both intrinsic and extrinsic apoptosis pathways. CONCLUSIONS: The results suggest that MSCs carrying oncolytic NDV in combination with L. casei extract as a potentially effective strategy for cancer immunotherapy by promoting the generation of LDH, ROS, and apoptosis in the microenvironment of the CT26 cell line.

Exosomes derived from rapamycin-treated 4T1 breast cancer cells induced polarization of macrophages to M1 phenotype.

M2 macrophages are the most prevalent type in the tumor microenvironment and their polarization to M1 type can be used as a potential cancer immunotherapy. Here, we investigated the role of tumor microenvironment and particularly purified exosomes in M2 to M1 macrophage polarization. Rapamycin treatment on triple-negative breast cancer cells (TNBC) was performed. Tumor cells-derived exosomes (called texosomes) were isolated and characterized using scanning electron microscopy, transmission electron microscopy, dynamic light scattering, high-performance liquid chromatography, Fourier transform infrared, and Western blot assays. M2 mouse peritoneal macrophages were treated with rapamycin or rapamycin-texosome. Then, M1/M2 phenotype-specific marker genes and proteins were measured to assess the degree of M2 to M1 polarization. Finally, nitric oxide (NO) production, phagocytosis, and efferocytosis assays were assessed to verify the functionality of the polarized macrophages. Purified rapamycin-texosomes significantly increased the expression of the M1 markers (Irf5, Nos2, and CD86) and decreased M2 markers (Arg, Ym1, and CD206). In addition, the levels of M1-specific cytokines tumor necrosis factor alpha and interleukin 1ß (IL-1ß) were increased, whereas the levels of M2 specific cytokines IL-10 and transforming growth factor beta were declined. Furthermore, texosome treatment increased NO concentration and phagocytosis and decreased efferocytosis indicating M1 polarization. These findings suggest rapamycin-texosomes can induce M2 to M1 macrophages polarization as a potential immunotherapy for TNBC.

MicroRNA-122 Is More Effective than Rapamycin in Inhibition of Epithelial-mesenchymal Transition and mTOR Signaling Pathway in Triple Negative Breast Cancer.

The fundamental mechanism responsible for the aggressiveness of metastatic cancers such as triple-negative breast cancer (TNBC) is the epithelial-mesenchymal transition (EMT). In cancer microenvironments, the Phosphoinositide 3-kinases (PI3K)-Akt- mammalian target of rapamycin (mTOR) signaling pathway plays a critical role in regulating the EMT mechanism. The current study focuses on the impacts of rapamycin, a newly retargeted chemotherapeutic agent against mTOR, and MicroRNA (miR)-122 on the aggressive behavior of TNBC.  The half-maximal inhibitory concentration (IC50) of rapamycin on 4T1 cells was determined using an MTT assay. Also, miR-122 was transiently transfected into 4T1 cells to study its effect on the pathway. Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to assess the expression level of central mTOR and EMT-related cascade genes. Moreover, cell mobility and migration were evaluated using scratch and migration assays, respectively. Both rapamycin and miR-122 significantly decreased the expression levels of PI3K, AKT, and mTOR, as well as ZeB1 and Snail genes. However, no significant change was observed in Twist gene expression. Furthermore, scratch and migration assays revealed that the migration of 4T1 cells was markedly reduced, especially following miR-122 induction. Our experimental findings and gene enrichment studies indicated that miR-122 mainly operates on multiple metabolic pathways, as well as EMT and mTOR, while rapamycin has restricted targets in cancer cells.  Consequently, miR-122 can be considered a potential cancer microRNA therapy option, which can be validated in the future in animal studies to demonstrate its efficacy in cancer control.

Design of a multi-epitope-based vaccine consisted of immunodominant epitopes of structural proteins of SARS-CoV-2 using immunoinformatics approach.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has shown rapid global spread and has resulted in a significant death toll worldwide. In this study, we aimed to design a multi-epitope vaccine against SARS-CoV-2 based on structural proteins S, M, N, and E. We identified B- and T-cell epitopes and then the antigenicity, toxicity, allergenicity, and similarity of predicted epitopes were analyzed. T-cell epitopes were docked with corresponding HLA alleles. Consequently, the selected T- and B-cell epitopes were included in the final construct. All selected epitopes were connected with different linkers and flagellin and pan-HLA DR binding epitopes (PADRE) as an adjuvant were used in the vaccine construct. Furthermore, molecular docking was used to evaluate the complex between the final vaccine construct and two alleles, HLA-A*02:01 and HLA-DRB1*01:01. Finally, codons were optimized for in silico cloning into pET28a(+) vector using SnapGene. The final vaccine construct comprised 11 CTL, HTL, and B-cell epitopes corresponding to 394 amino acid residues. In silico evaluation showed that the designed vaccine might potentially promote an immune response. Further in vivo preclinical and clinical testing is required to determine the safety and efficacy of the designed vaccine.

Recombinant expression of SARS-CoV-2 receptor binding domain (RBD) in Escherichia coli and its immunogenicity in mice.

Objectives: The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), giving rise to the coronavirus disease 2019 (COVID-19), has become a danger to wellbeing worldwide. Thus, finding efficient and safe vaccines for COVID-19 is of great importance. As a basic step amid contamination, SARS-CoV-2 employs the receptor-binding domain (RBD) of the spike protein to lock in with the receptor angiotensin-converting enzyme 2 (ACE2) on host cells. SARS-CoV-2 receptor-binding domain (RBD) is the main human antibody target for developing vaccines and virus inhibitors, as well as neutralizing antibodies. A bacterial procedure was developed for the expression and purification of the SARS-CoV-2 spike protein receptor-binding domain. Materials and Methods: In this research study, RBD was expressed by Escherichia coli and purified with Ni-NTA chromatography. Then it was affirmed by the western blot test. The immunogenicity and protective efficacy of RBD recombinant protein were assessed on BALB/c mice. Additionally, RBD recombinant protein was tested by ELISA utilizing sera of COVID-19 healing patients contaminated with SARS-CoV-2 wild type and Delta variation. Results: Indirect ELISA was able to detect the protein RBD in serum of the immunized mouse expressed in E. coli. The inactive SARS-CoV2 was detected by antibodies within the serum of immunized mice. Serum antibodies from individuals recovered from Covid19 reacted to the expressed protein. Conclusion: Our findings showed that RBD is of great importance in vaccine design and it can be used to develop recombinant vaccines through induction of antibodies against RBD.

Overview of the pre-clinical and clinical studies about the use of CAR-T cell therapy of cancer combined with oncolytic viruses.

BACKGROUND: Cancer is one of the critical issues of the global health system with a high mortality rate even with the available therapies, so using novel therapeutic approaches to reduce the mortality rate and increase the quality of life is sensed more than ever. MAIN BODY: CAR-T cell therapy and oncolytic viruses are innovative cancer therapeutic approaches with fewer complications than common treatments such as chemotherapy and radiotherapy and significantly improve the quality of life. Oncolytic viruses can selectively proliferate in the cancer cells and destroy them. The specificity of oncolytic viruses potentially maintains the normal cells and tissues intact. T-cells are genetically manipulated and armed against the specific antigens of the tumor cells in CAR-T cell therapy. Eventually, they are returned to the body and act against the tumor cells. Nowadays, virology and oncology researchers intend to improve the efficacy of immunotherapy by utilizing CAR-T cells in combination with oncolytic viruses. CONCLUSION: Using CAR-T cells along with oncolytic viruses can enhance the efficacy of CAR-T cell therapy in destroying the solid tumors, increasing the permeability of the tumor cells for T-cells, reducing the disturbing effects of the immune system, and increasing the success chance in the treatment of this hazardous disease. In recent years, significant progress has been achieved in using oncolytic viruses alone and in combination with other therapeutic approaches such as CAR-T cell therapy in pre-clinical and clinical investigations. This principle necessitates a deeper consideration of these treatment strategies. This review intends to curtly investigate each of these therapeutic methods, lonely and in combination form. We will also point to the pre-clinical and clinical studies about the use of CAR-T cell therapy combined with oncolytic viruses.

Combination therapy with CAR T cells and oncolytic viruses: a new era in cancer immunotherapy.

Chimeric antigen receptor (CAR) T-cell therapy is an encouraging and fast-growing platform used for the treatment of various types of tumors in human body. Despite the recent success of CAR T-cell therapy in hematologic malignancies, especially in B-cell lymphoma and acute lymphoblastic leukemia, the application of this treatment approach in solid tumors faced several obstacles resulted from the heterogeneous expression of antigens as well as the induction of immunosuppressive tumor microenvironment. Oncolytic virotherapy (OV) is a new cancer treatment modality by the use of competent or genetically engineered viruses to replicate in tumor cells selectively. OVs represent potential candidates to synergize the current setbacks of CAR T-cell application in solid tumors and then and overcome them. As well, the application of OVs gives researches the ability to engineer the virus with payloads in the way that it selectively deliver a specific therapeutic agents in tumor milieu to reinforce the cytotoxic activity of CAR T cells. Herein, we made a comprehensive review on the outcomes resulted from the combination of CAR T-cell immunotherapy and oncolytic virotherapy for the treatment of solid cancers. In the current study, we also provided brief details on some challenges that remained in this field and attempted to shed a little light on the future perspectives.

Detection of COVID-19 in tears of ICU-admitted patients with SARS-CoV-2 infection.

PURPOSE: Upon the outbreak of 2019, novel coronavirus (COVID-19) pandemic confirmed the cases surpassed 20 million. Despite a few reports identified the association of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with ocular manifestations, it may assess the ocular symptoms of patients with the COVID-19 by ophthalmologists facilitate the diagnosis and prevent transmission. METHODS: A total of 60 patients with the COVID-19 admitted to Baghiatallah hospital from March 2020 to May 2020 were retrospectively reviewed and analyzed for the ocular manifestations, blood tests, and reverse transcriptase-polymerase chain reaction (RT-PCR) for SARS-CoV-2 using nasopharyngeal and conjunctival swabs. RESULTS: Among 60 included patients with clinically confirmed COVID-19, the median age 58.36 years (IQR: 30-88 years), 27 (45%) were male. Furthermore, 29 (48%) and 5 (8%) patients yielded positive for SARS-CoV-2 on RT-PCR from nasopharyngeal swabs and conjunctival specimens, respectively. Among 60 patients, 10 (16%) and 3 (5%), respectively, had the ocular manifestations and positive results for SARS-CoV-2 on RT-PCR from conjunctival and nasopharyngeal swabs. CONCLUSION: Although the positive rate of tear RT-PCR rate is not noticeable as nasopharyngeal swabs yet, COVID-19 transmission through the eyes is biologically plausible.

Therapeutic potential of CAR T cell in malignancies: A scoping review.

Although tremendous advancements in cancer therapy over the last several years, cancer still is a complex illness to cure. Traditional cancer treatments, including chemotherapy, radiotherapy, and surgery, have a poor therapeutic effect, emphasizing the significance of employing innovative treatments like activated cell therapy. Chimeric antigen receptor T cell is one of the most prevalent types of activated cell therapy have been developed to direct T lymphocytes toward cancers (CAR-T cells). CAR-T cells therapy has illustrated poor impact versus solid tumors despite the remarkable success in patients suffering from hematological malignancies. CAR-T cells must overcome various hurdles to obtain full responses to solid tumors, including growth, stability, trafficking, and destiny inside tumors. As a result, novel treatment methods will entail overcoming the challenges that CAR-T cells face in solid tumors. The use of CAR-T cells in combination with other therapeutic approaches such as chemotherapy, radiotherapy, immuno-checkpoint inhibitors, and oncolytic viruses can promote the effectiveness of CAR-T cell therapy for the treatment of solid tumors. However, more research is needed to determine the safety and effectiveness of these therapies. CAR-T cell treatment success rates vary by type of disease, but are predicted to reach up to 90% in patients with leukemia. However, since this kind of immunotherapy is still in its infancy, there is much to learn about its efficacy. This review provided an in-depth examination of CAR-T cell therapy and its success and failure as a cancer treatment approach. We also discuss combination therapies with CAR-T Cell.

Comparison of oncolytic virotherapy and nanotherapy as two new miRNA delivery approaches in lung cancer.

Lung cancer is known as the second leading cause of cancer death. Finding ways to detect early-stage lung cancer can remarkably increase the survival rate. Biomarkers such as microRNAs can be helpful in cancer diagnosis, predicting its prognosis, and patients' chances of survival. Numerous studies have confirmed the correlation between microRNA expression and the likelihood of patients surviving after treatment. Consequently, it is necessary to study the expression profile of microRNAs during and after treatment. Oncolytic virotherapy and nanotherapy are two neoteric methods that use various vectors to deliver microRNAs into cancer cells. Although these treatments have not yet entered into the clinical trials, much progress has been made in this area. Analyzing the expression profile of microRNAs after applying nanotherapy and oncolytic virotherapy can evaluate the effectiveness of these methods. This review refers to the studies conducted about these two approaches. The advantages and disadvantages of these methods in delivery and affecting microRNA expression patterns are discussed below.

Droplet digital PCR of viral DNA/RNA, current progress, challenges, and future perspectives.

High-throughput droplet-based digital PCR (ddPCR) is a refinement of the conventional polymerase chain reaction (PCR) methods. In ddPCR, DNA/RNA is encapsulated stochastically inside the microdroplets as reaction chambers. A small percentage of the reaction chamber contains one or fewer copies of the DNA or RNA. After PCR amplification, concentrations are determined based on the proportion of nonfluorescent partitions through the Poisson distribution. Some of the main features of ddPCR include high sensitivity and specificity, absolute quantification without a standard curve, high reproducibility, good tolerance to PCR inhibitor, and high efficacy compared to conventional molecular methods. These advantages make ddPCR a valuable addition to the virologist's toolbox. The following review outlines the recent technological advances in ddPCR methods and their applications in viral identification.

Oncolytic Viruses and Cancer, Do You Know the Main Mechanism?

The global rate of cancer has increased in recent years, and cancer is still a threat to human health. Recent developments in cancer treatment have yielded the understanding that viruses have a high potential in cancer treatment. Using oncolytic viruses (OVs) is a promising approach in the treatment of malignant tumors. OVs can achieve their targeted treatment effects through selective cell death and induction of specific antitumor immunity. Targeting tumors and the mechanism for killing cancer cells are among the critical roles of OVs. Therefore, evaluating OVs and understanding their precise mechanisms of action can be beneficial in cancer therapy. This review study aimed to evaluate OVs and the mechanisms of their effects on cancer cells.

Concise review on optimized methods in production and transduction of lentiviral vectors in order to facilitate immunotherapy and gene therapy.

Lentiviral vectors (LVs) have provided an efficient way to integrate our gene of interest into eukaryote cells. Human immunodeficiency virus (HIV)-derived LVs have been vastly studied to become an invaluable asset in gene delivery. This abled LVs to be used in both research laboratories and gene therapy. Pseudotyping HIV-1 based LVs, abled it to transduce different types of cells, especially hematopoietic stem cells. A wide range of tropism, plus to the ability to integrate genes into target cells, made LVs an armamentarium in gene therapy. The third and fourth generations of self-inactivating LVs are being used to achieve safe gene therapy. Not only advanced methods enabled the clinical-grade LV production on a large scale, but also considerably heightened transduction efficiency. One of which is microfluidic systems that revolutionized gene delivery approaches. Since gene therapy using LVs attracted lots of attention to itself, we provided a brief review of LV structure and life-cycle along with methods for improving both LV production and transduction. Also, we mentioned some of their utilization in immunotherapy and gene therapy.

Epidemiological characteristics of coronavirus disease 2019 (COVID-19) patients in IRAN: A single center study.

BACKGROUND: An outbreak of COVID-19 in Iran has spread throughout the country. Identifying the epidemiological characteristics of this disease will help to make appropriate decisions and thus control the epidemic. The aim of this study was characterization of the epidemiological features of COVID-19 in Iran. METHODS: In this retrospective study, data related to the epidemiological characteristics of COVID-19 patients admitted to Baqiyatallah Hospital in Tehran, Iran, from 19 February 2020 to 15 April 2020 have been analyzed and reported. Patient characteristics including age, gender and underlying diseases were investigated. Data were collected through patient records. Sex ratio, Case Fatality Rate (CFR) and daily trend of cases were also determined. A multiple logistic regression analysis was also performed to assess affecting factors on mortality. RESULTS: From February 19, 2020 to April 15, 2020, 12870 patients referred to the hospital emergency department, of which 2968 were hospitalized with COVID-19 diagnosis. The majority of cases were in the age group of 50 to 60 years of old. The male-to-female ratio was 1.93:1. A total of 239 deaths occurred among all cases for an overall CFR of 1.85% based on the total number of patients (both outpatient and inpatient) and 8.06% among hospitalized patients. Out of all patients 10.89% had comorbidity. Diabetes, chronic respiratory diseases, hypertension, cardiovascular diseases, chronic Kidney diseases and cancer were the most common comorbidities with 3.81, 2.02 , 1.99 , 1.25, 0.60 and 0.57 %, respectively. Male gender (OR=1.45, 95% CI: 1.08-1.96), older age (OR=1.05, 95% CI: 1.04-1.06) and having underlying diseases (OR=1.53, 95% CI: 1.04-2.24) were significantly associated with mortality. CONCLUSIONS: The results of this study showed that Male gender, older age and having comorbidities were significantly associated with the risk of death among COVID-19 patients. It is important to pay special attention to male elderly patients with underlying diseases.

Detection of West Nile virus by real-time PCR in crows in northern provinces of Iran.

BACKGROUND & OBJECTIVES: West Nile virus (WNV) is a positive-sense, single-stranded RNA virion, that belongs to the Flaviviridae family. This virus is preserved in a bird-mosquito cycle that is capable of inducing diseases as a dead-end or endpoint host in humans as well as horses. In 2016, a suspicious case of crow population death was reported by the Department of Environment, Ministry of Health, Iran. Considering the mass migration of birds together with the WNV-related symptoms, including uncoordinated walking, ataxia, inability to fly, lack of awareness, and abnormal body posture, it was necessary to further investigate the possible causes of this incident. The objective of this study was molecular detection of WNV in crows utilizing the real-time PCR method in the northern provinces of Iran. METHODS: A total of 12 crows (8 dead, 4 alive) with a possible WNV infection, were collected from the northern provinces of Iran (Golestan, Mazandaran, and Guilan). A tissue sample of the liver, kidney, or lung was collected from all the crows, and RNA was isolated using an RNA extraction kit. A one-step real-time PCR method using a TaqMan probe was used for virus detection. RESULTS: All the infected crows were positive for WNV. The 132-bp real-time PCR amplicon of the genome was detected in all the samples. Comparative phylogenetic analysis revealed that WNV isolated from Iran clustered with strains from the USA, Hungary, and Culex pipiens. INTERPRETATION & CONCLUSION: The WNV genome sequence was detected in all the infected crows. The results confirmed the connection of this isolation with clade1a strains. Hence, determining the epidemiologic and prevalence characteristics of the WNV for transmission control is of critical importance in Iran.