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Toxoplasmosis is a cosmopolitan zoonotic infection, caused by a unicellular protozoan parasite known as Toxoplasma gondii that belongs to the phylum Apicomplexa. It is estimated that over one-third of the world's population has been exposed and are latently infected with the parasite. In humans, toxoplasmosis is predominantly asymptomatic in immunocompetent persons, while among immunocompromised individuals may be cause severe and progressive complications with poor prognosis. Moreover, seronegative pregnant mothers are other risk groups for acquiring the infection. The life cycle of T. gondii is very complex, indicating the presence of a plurality of antigenic epitopes. Despite of great advances, recognize and construct novel vaccines for prevent and control of toxoplasmosis in both humans and animals is still remains a great challenge for researchers to select potential protein sequences as the ideal antigens. Notably, in several past years, constant efforts of researchers have made considerable advances to elucidate the different aspects of the cell and molecular biology of T. gondii mainly on microneme antigens, dense granule antigens, surface antigens, and rhoptry proteins (ROP). These attempts thereby provided great impetus to the present focus on vaccine development, according to the defined subcellular components of the parasite. Although, currently there is no commercial vaccine for use in humans. Among the main identified T. gondii antigens, ROPs appear as a putative vaccine candidate that are vital for invasion procedure as well as survival within host cells. Overall, it is estimated that they occupy about 1%–30% of the total parasite cell volume. In this review, we have summarized the recent progress of ROP-based vaccine development through various strategies from DNA vaccines, epitope or multi epitope-based vaccines, recombinant protein vaccines to vaccines based on live-attenuated vectors and prime-boost strategies in different mouse models.
Subject(s)
Animals , Humans , Mice , Antigens, Surface , Apicomplexa , Cell Size , Epitopes , Immunization , Life Cycle Stages , Molecular Biology , Mothers , Parasites , Prognosis , Toxoplasma , Toxoplasmosis , Vaccines , Vaccines, DNA , Vaccines, Synthetic , ZoonosesABSTRACT
Background: Leishmaniasis is caused by parasitic protozoa of the genus Leishmania which is an obligate intracellular parasite in the infected host. Individuals who have been recovered from clinical leishmaniasis develop strong immunity against reinfection. DNA vaccines are the new type of vaccines that induce expression of protein eukaryotic cells. DNA vaccines can be stimulated by the cellular and humoral immune responses using one or several genes
Methods: A DNA vaccine containing plasmids encoding the pcLACK+pcTSA genes of Leishmania major [L. major] [MHRO/IR/75/ER] in the vicinity of IL-12 gene expression was made and then its protective efficacy in comparison with single-gene of LACK was evaluated. Also, BALB/c mice were immunized intramuscularly three times. The humoral and cellular immune responses were evaluated after immunization with pcLACK, pcLACK+pcTSA+pCAGGS-IL12, and then challenged with L. major
Results: Humoral response and IFN-Gamma values were significantly higher than control groups after immunization with pcLACK, pcLACK+pcTSA+pCAGGS-IL12 and challenge with L. major [p
Conclusion: The survival time of the immunized mice with pcLACK, pcLACK+pcTSA+ pCAGGS-IL12 groups was higher than the control groups. Then, DNA vaccine of pcLACK appeared to be likely able to induce more protection against infection with L. major in mice. Therefore, cocktail DNA is effective to enhance specific immunity
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Background: Mutations in the coding region of the Chemokine Receptor 5 [CCR5] genes reduce or eliminate CCR5 expression in immune cells and progression of HCV infection. This study aimed to investigate the role of this mutation in HCV infection in Iranian patients in comparison with healthy individuals
Methods: 100 HCV infected patients and 100 healthy individuals were randomly selected. The CCR5-DELTA32 genotypes were determined using specific primers and PCR method
Results: The agarose gel electrophoresis showed a189-bp fragment from wild type for both alleles of CCR5 gene. The CCR5-DELTA32 allele was not found in any HCV infected and healthy subjects
Conclusion: The mutation in CCR5 gene was not detected in any of the two groups; therefore, the role of CCR5 gene expression in immune cells and progression of HCV infection needs to be studied in larger samples in our country
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Background: The severe damages of toxoplasmosis clearly indicate the need for the development of a more effective vaccine. Immunization with plasmid DNA is a promising vaccination technique. Therefore, GRA7 plasmid was prepared to be used as a vaccine. The purpose of this study was evaluation of immunization with cocktail DNA vaccine including plasmids encoding Toxoplasma gondii ROP2 and GRA7 in BALB/c mice
Methods: In this study, 733 bp of GRA7 gene was cloned in pCDNA3.1 plasmid as an expression vector. The plasmids containing GRA7 and ROP2 genes were administered via IM according to immunized mice three times with a 3 week interval. For lymphocyte proliferation and cytokine assay, splenocytes of immunized mice were cultured for proliferation and cytokine assay. The other mice in each group were inoculated by the parasite and mortality of the mice was evaluated on a daily basis
Results: The cytokine assay results and lymphocyte proliferation response in cocktail DNA vaccines showed that IFN-gamma levels were significantly higher than controls [p<0.05], whereas IL-4 expression level in BALB/c mice immunized with cocktail was lower than that in control groups and these results are confirmed by MTT test. Predominance of the levels of IgG2a over IgG1 was observed in sera of the immunized mice. Furthermore, IgG2a values in cocktail DNA vaccines pcGRA7 were significantly higher than control group [p<0.01]. In contrast, IgG1 antibodies were similar between the two groups [p>0.5]. So, survival time in the immune groups was significantly prolonged in comparison to control ones [p<0.01]
Conclusion: The immunized mice by DNA vaccine produce higher titration of IFNgamma, indicated with Th1 response which is confirmed by high level of IgG2a. These data demonstrate that the cocktail GRA7/ROP2 is a potential vaccine candidate against toxoplasmosis
ABSTRACT
Vaccination would be the most important strategy for the prevention and elimination of leishmaniasis.The aim of the present study was to compare the immune responses induced following DNA vaccinationwith LACK (Leishmania analogue of the receptor kinase C), TSA (Thiol-specific-antioxidant) genesalone or LACK-TSA fusion against cutaneous leishmaniasis (CL). Cellular and humoral immuneresponses were evaluated before and after challenge with Leishmania major (L. major). In addition,the mean lesion size was also measured from 3th week post-infection. All immunized mice showed apartial immunity characterized by higher interferon (IFN)-γ and Immunoglobulin G (IgG2a) levelscompared to control groups (p<0.05). IFN-γ/ Interleukin (IL)-4 and IgG2a/IgG1 ratios demonstratedthe highest IFN-γ and IgG2a levels in the group receiving LACK–TSA fusion. Mean lesion sizesreduced significantly in all immunized mice compared with control groups at 7th week post-infection(p<0.05). In addition, there was a significant reduction in mean lesion size of LACK-TSA andTSA groups than LACK group after challenge (p<0.05). In the present study, DNA immunizationpromoted Th1 immune response and confirmed the previous observations on immunogenicity ofLACK and TSA antigens against CL. Furthermore, this study demonstrated that a bivalent vaccinecan induce stronger immune responses and protection against infectious challenge with L. major.
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Background: Cervical cancer is the second most common female cancer worldwide. Inhibitors of apoptosis proteins [IAPs] block apoptosis; therefore, therapeutic strategies targeting IAPs have attracted the interest of researchers in recent years. Apollon, a member of IAPs, inhibits apoptosis and cell death. RNA interference is a pathway in which small interfering RNA [siRNA] or shRNA [short hairpin RNA] inactivates the expression of target genes. The purpose of this study was to determine the effect of constructed shRNAs on apoptosis and growth inhibition through the suppression of apollon mRNA in HeLa cell line
Methods: Three shRNAs with binding ability to three different target sites of the first region of apollon gene were designed and cloned in pRNAin-H1.2/Neo vector. shRNA plasmids were then transfected in HeLa cells using electroporation. Down-regulation effects of apollon and the viability of HeLa cells were analyzed by RT-PCR, lactate dehydrogenase assay, and MTT assay, respectively. Also, the induction and morphological markers of apoptosis were evaluated by caspase assay and immunocytochemistry method
Results: The expression of shRNA in HeLa cells caused a significant decrease in the level of apollon mRNA1. In addition, shRNA1 effectively increased the mRNA level of Smac [as the antagonist of apollon], reduced the viability of HeLa cells and exhibited immunocytochemical apoptotic markers in this cell line
Conclusion: Apollon gene silencing can induce apoptosis and growth impairment in HeLa cells. In this regard, apollon can be considered a candidate therapeutic target in HeLa cells as a positive human papillomavirus cancer cell line
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Background: As a drug target and an antigenic agent, HIV-1 protease [HIV-1 PR] is at the center of attention for designing anti-AIDS inhibitors and diagnostic tests. In previous studies, the production of the recombinant protease has been faced with several difficulties; therefore, the aims of this study were the easy production, purification of the soluble form of protease in E. coli and investigation of its immunoreactivity
Methods: Protease coding region was isolated from the serum of an infected individual, amplified by RT-PCR and cloned into PTZ57R using TA-cloning. Protease coding frame was isolated by PCR and cloned in pET102/D. TOPO expression vector and cloned protease was expressed in Escherichia coli [E. coli] BL21. Produced recombinant protein was purified by affinity Ni-NTA column and protein concentration was checked by BCA protein assay kit. Subsequently, immunoreactivity of recombinant protease [rPR] was assayed by Western blotting and ELISA
Results: Cloning of the HIV protease by TOPO cloning system in pET102/D.TOPO was confirmed with PCR and sequencing. The concentration range of purified recombinant protein was 85 to 100 micro g/ml. Immunogenicity of rPR was confirmed by Western blotting and ELISA
Conclusion: Soluble production of recombinant HIV-1 protease [HIV-1 rPR] was performed successfully. This recombinant protein disclosed 86% specificity and 90% sensitivity in immunoassay tests
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Background: Activated platelets shed microparticles [MPs] in vivo and certainly in vitro under storage. Like platelets, platelet-derived MPs contribute to hemostatic and inflammatory responses. We sought to determine the interactions between platelet MPs and peripheral B lymphocytes in the healthy blood circulation to propose a possible role for platelet MPs in the functioning of B cells
Materials and Methods: An enzyme-linked immunosorbent assay [ELISA] was established to determine the normal interactions between human peripheral blood B lymphocytes and platelet MPs. B cells were isolated and bound to the wells of microtiter plates using coated anti-CD19. Then the presence of attached MPs was surveyed. Also, platelet MPs were separated from human platelet concentrates and applied to confirm the new binding capacities of B cells for these microvesicles
Results: Platelet MPs were recognized in the wells of ELISA in which only B cells were isolated. So MPs were bound with peripheral blood B cells. Furthermore, using this method, the role of CD40/ CD40L interaction was displayed for the binding
Conclusion: It seemed that the binding of platelet MPs to B cells normally took place in vivo and a percent of B cells circulate in blood in connection with platelet MPs
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Background: Detection of hepatitis C virus specific antibodies is the initial step in chronic HCV diagnosis. HCV NS4B is among the most immunogenic HCV antigens and has been widely used in commercial Enzyme Immunoassays [EIA]. Additionally, NS4B, a key protein in the virus replication, can be an alternative target for antiviral therapy
Objectives: Development of a new method for high-level expression and purification of NS4B coding region was the aim of the report
Materials and Methods: Viral RNA was purified from the serum of an HCV positive patient and NS4B coding region was amplified using nested RT-PCR. PCR products were cloned into pET102/D-TOPO expression vector and transformed into E. coli BL21. Induction was performed by adding 1 mM isopropyl-beta-D-thiogalactopyranoside [IPTG] to the culture medium. Immunoreactivity of the purified recombinant proteins was evaluated by immunoblotting and indirect enzymelinked immunosorbent assay [ELISA]
Results: The recombinant NS4B protein was expressed and its immunoreactivity was confirmed by ELISA and western blotting
Conclusions: The directional TOPO cloning provides an efficient and easy platform for heterologous expression of immunoreactive HCV NS4B
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Streptococcus group B [GBS] or Streptococcus agalactiae is typically associated with neonatal disease and infection in pregnant women. Mortality of GBS sepsis in neonates is over 50% and is particularly high in preterm infants. GBS also causes invasive infection in pregnant and non-pregnant women including urinary tract infection [UTI]. Penicillin-derived antibiotics remained as choice drugs for treatment of GBS infection; however, Erythromycin and Clindamycin are useful in cases of allergic to Penicillin. The aim of this study was to investigate the resistance to Erythromycin and Clindamycin, especially inducible Clindamycin resistance, in GBS isolated from urinary samples of women who attended medical offices in Tehran, Iran. This study was conducted on 5000 urine samples from Jan. 2011 to Oct. 2012 that 104 GBS were isolated. The isolates were identified as GBS using laboratory criteria. Antimicrobial susceptibility test was done by Erythromycin disk 15microg and Clindamycin disk 2microg for observation inducible resistant D-zone test by double-disk diffusion method with Erythromycin and adjacent Clindamycin. Among the 5000 urine samples 104 [2.08%] were Beta hemolytic GBS. Of the 104 isolated GBS, 22 [21.2%] were resistance, 24 [23%] were intermediate, and 58 [55.8%] were susceptible to Erythromycin; however, 24 [23%] were resistance, 5 [4.8%] were intermediate, and 75 [72.2%] were susceptible to Clindamycin. Of the 22 Erythromycin-resistant isolates, 10 [9.5% in total GBS isolated] displayed the D zone; it means they have inducible Erythromycin resistant to Clindamycin. Various studies in other countries report lower rates of inducible Clindamycin resistance; it indicates the use of more macrolides in the treatment of UTI
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OBJECTIVE@#To investigate the protective effect of IL-22 and IL-12 on cutaneous leishmaniasisin BALB/c mice.@*METHODS@#The protective effect of IL-22 and IL-12 on cutaneous leishmanias in BALB/c mice was evaluated by measurement of IL-4, INF-γ, total IgG, IgG1 and IgG2a after challenge with Leishamania major. Clinical evaluations were performed by measurement of lesion diameter, and survival rate of the mice.@*RESULTS@#In week 27 post infection, the mortality rates for control groups were 100%. While the survival rates for the IL-12, IL-12 + IL-22, and IL-22(5 ng/g) groups were 100%. The size of lesions decreased in the presence IL-22 (5 ng/g) of mice weight, which was statistically significant in comparison with other groups (P<0.05). Mean of total IgG, IgG1 and IgG2a for IL-22 (5 ng/g) group was more than other groups. In IL-22 group (5 ng/g), INF-γ production was significantly higher than other groups and IL-4 was significantly lower than other groups.@*CONCLUSIONS@#The results obtained indicate the effectiveness of IL-22 and its effect on IL-12 in protection of cutaneous leishmaniasis.
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The HBV-X [HBX] protein is believed to contribute to the development of HCC. However, the molecular mechanisms involved in HBX-mediated hepatocarcinogenesis remain obscure. In this study, the effect of hepatitis B virus X gene and its protein product HBxAg on expression of p53 gene in Hep G2 cell line was investigated. Viral DNA extracted from HBV-positive serum and HBX gene region was amplified using polymerase chain reaction [PCR]. Then, PCR product was cloned into the pcDNA3 vector. After confirmation of cloning, the recombinant plasmid pcDNA3-X was transfected into HepG2 cell line using lipid-mediated DNA-transfection procedure. SDS-PAGE and western blotting methods were used to identify expression of HBX protein. Relative quantification was used to analyze the p53gene expression using the 2-[delta delta Ct] method. Recombinant plasmid pcDNA3-HBX was confirmed by restriction endonucleases digestion and colony-PCR. The results of SDS-PAGE and western blot assays showed that HBX gene could be expressed in Hep G2 cell line. There was no significant difference between the expression levels of p53 compared with GAPDH gene as housekeeping gene [p<0.05]. There was no significant difference in the protein levels between the transfected cells with X gene containing HBX130 and HBX131 double mutations and p53 gene. It is necessary to do more studies on Hepatitis B virus to understand the role of HBX on the development of liver cancer and its function on p53 tumor suppressor protein
Subject(s)
Gene Expression , Trans-Activators , Genes, p53 , Hep G2 CellsABSTRACT
There is a concern on safety of human Fresh Frozen Plasma [FFP] as it is a source of some medicinal products. The possibility of transmission of blood-borne are reported often due to emerging viruses. There are some Pathogen Reduction Technologies [PRT] to inactivate viruses. Methylene Blue [MB] based method is one of them. The aim of this study was to examine new designated device to inactivate model viruses. Four model viruses were used in this study: Vesicular stomatitis virus [VSV], Herpes Simplex Virus I [HSV-1], Bovine Viral Diarrhea Virus [BVDV] and Polio Virus. 50% Tissue Culture Infective Dose [TCID 50] and Reed-Muench Methods were used to titer the viruses. MB in two final concentration of 0.1 microM and 1 microM and illumination in about 627 nm with red LED [Lamp Emitting Diode] for 15, 30, 45 and 60 minutes were used. Three replicates employed for each experiments. 1 microM concentration of MB showed more effective than 0.1 microM in all designed illumination period for inactivation of HSV, VSV and BVDV. This method also demonstrated best results for enveloped model viruses. The most Log reduction for HSV, VSV and BVDV were 6.28, 5.54 and 6.22, respectively. For HSV and BVDV inactivation, the best illumination period was 45 minutes. Model viruses showed sensitivity combination of MB and illumination using red LEDs. As results show this device could inactivate model viruses and reduce their titer very close to approved commercial devices, in compare
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Understanding of the natural history of chronic HBV infection is useful for presenting the optimal management of chronic HBV infection. The aim of this study was to evaluate the natural history of chronic hepatitis B infection. In this cross sectional study, 219 untreated chronic hepatitis B patients from Jan. 2010 to Aug. 2012 were included. The subjects were classified in four groups based on serological, biochemical and molecular testing, Serological tests for HBeAg and HBeAb were performed by ELISA method. HBV DNA viral loads were detected by using Light Cycler instrument and ALT/AST levels were assessed by automatic analyzer. The majority of subjects [94.1%] were HBeAg negative. Of 13 HBeAg positive patients, 5 [2.3%] and 8[3.7%] were considered as immunetolerant and immune reactive, respectively. Of 206 HBeAg negative patients, there were 142 [64.8%] patients in inactive or low replicative phase and 64[29.2%] were in HBeAg negative chronic hepatitis B phase. The lowest rate of subjects were in immunetolerant phase and most of them had above 20 years old that confirmed successful neonatal vaccines in our country. The highest rate of chronic HBV infected patients were in low replicative phase of chronic hepatitis B infection. Although, it is not recommended to treat these patients, but liver function and also liver biopsy should be considered in patients above 40 years of age
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Objective: To investigate the protective effect of IL-22 and IL-12 on cutaneous leishmaniasisin BALB/c mice. Methods: The protective effect of IL-22 and IL-12 on cutaneous leishmanias in BALB/c mice was evaluated by measurement of IL-4, INF-γ, total IgG, IgG1 and IgG2a after challenge with Leishamania major. Clinical evaluations were performed by measurement of lesion diameter, and survival rate of the mice. Results: In week 27 post infection, the mortality rates for control groups were 100%. While the survival rates for the IL-12, IL-12 + IL-22, and IL-22(5 ng/g) groups were 100%. The size of lesions decreased in the presence IL-22 (5 ng/g) of mice weight, which was statistically significant in comparison with other groups (. P<0.05). Mean of total IgG, IgG1 and IgG2a for IL-22 (5 ng/g) group was more than other groups. In IL-22 group (5 ng/g), INF-γ production was significantly higher than other groups and IL-4 was significantly lower than other groups. Conclusions: The results obtained indicate the effectiveness of IL-22 and its effect on IL-12 in protection of cutaneous leishmaniasis.
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Platelets are anucleated fragments derived from megakaryocytes. It has been demonstrated that platelets play a role in hemostasis and innate immunity. In addition, platelets have a CD40 ligand which is an important molecular marker in motivating immune cells. Thus, platelets also have a role in adaptive immunity as seen by their ability to activate B cells. Since human platelet microparticles [MPs] originate from platelets, we have chosen to examine the effects of MPs on B cell activation. Platelet MPs were isolated from platelet concentrates obtained from the Tehran Blood Transfusion Center. The MPs were co-cultured with B cells isolated from human whole blood with magnetic beads using negative selection. After seven days, the expression of activation markers CD27 and CD86, as well as IgD were evaluated by flow cytometry. In a comparison between test [B cells/MPs] and control [B cells] cells we observed that the expression of activation markers CD27 and CD86 increased during the seven-day co-culture period. However, the expression of IgD antibody decreased. As with platelets, MPs can affect B cell activation during in vitro co-culture
Subject(s)
Humans , B-Lymphocytes , Cell-Derived Microparticles , Tumor Necrosis Factor Receptor Superfamily, Member 7 , B7-2 Antigen , Immunoglobulin DABSTRACT
Background: TSA (thiol-specific antioxidant antigen) is the immune-dominant antigen of Leishmania major and is considered to be the most promising candidate molecule for a recombinant or DNA vaccine against leishmaniasis. The aim of the present work was to express a plasmid containing the TSA gene in eukaryotic cells. Methods: Genomic DNA was extracted, and the TSA gene was amplified by polymerase chain reaction (PCR). The PCR product was cloned into the pTZ57R/T vector, followed by subcloning into the eukaryotic expression vector pcDNA3 (EcoRI and HindIII sites). The recombinant plasmid was characterised by restriction digest and PCR. Eukaryotic Chinese hamster ovary cells were transfected with the plasmid containing the TSA gene. Expression of the L. major TSA gene was confirmed by sodium dodecyl sulphate–polyacrylamide gel electrophoresis and Western blotting. Results: The plasmid containing the TSA gene was successfully expressed, as demonstrated by a band of 22.1 kDa on Western blots. Conclusion: The plasmid containing the TSA gene can be expressed in a eukaryotic cell line. Thus, the recombinant plasmid may potentially be used as a DNA vaccine in animal models.
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So far, recombinant antigens of HIV-1, the etiologic cause of Acquired Immunodeficiency Syndrome [AIDS], have been widely used for the diagnosis and vaccine development. P17 or the matrix protein formed by the proteolytic cleavage of gag is strongly antigenic and is as conserved and immunogenic as p24. In some cases, antibodies to p17 are more prevalent than antibodies to p24 and the decline in the level of p17 antibodies is an earlier prognostic marker for disease progression than decline in the level of antibodies to p24. The aim of this study was to clone and express the gag derived p17 protein in soluble form in E. coli and then assess the immunoreactivity of produced recombinant p17. DNA sequence encoding p17 matrix protein was cloned from PTZ-gag53-IR vector that has the complete gag polyprotein sequence. The T7-promoter-based expression system used in this study was TOPO directional cloning strategy that expressed p17 matrix protein in fusion with thioredoxin in E. Coli. Purification of produced recombinant protein has been done using Ni-NTA nickel chelating agarose beads. Sequencing result of the cloned sequence showed that it belongs to CRF35_AD subtype of HIV-1 which is highly prevalent in Iran and Afghanistan. The immunoreactivity of produced recombinant p17 to sera from infected individuals showed 93.8% sensitivity and 100% specificity
Subject(s)
Humans , HIV Antigens , Thioredoxins , Acquired Immunodeficiency Syndrome , AIDS Vaccines , Cloning, Molecular , Recombinant Fusion ProteinsABSTRACT
Hepatitis B is one of the most common infectious diseases worldwide that can be transmitted by blood transfusion. The hepatitis B virus [HBV] has eight different genotypes that show different geographical distributions and clinical manifestations. This study aims to investigate the sequence of the HBV polymerase gene and the frequency of HBV genotypes among Iranian blood donors. The sera of 223 blood donors who were positive for hepatitis B surface antigen [HbsAg] as determined by the ELISA method were selected. HBV DNA was extracted from the sera of 134 blood donors by a commercial kit, and the entire polymerase gene was amplified by nested-PCR. HBV genotypes were determined by direct sequencing of the HBV polymerase gene. Phylogenetic trees were constructed by the neighbor-joining [NJ] method. No known base mutations were found in the entire HBV polymerase gene of infected blood donors, and only genotype D was detected among HBV-infected blood donors. The sub-genotype D1 of HBV was dominant in the subjects. This study shows that antiviral-resistant mutations, such as lamivudine-resistant HBV strains, do not exist naturally among Iranian blood donors. More studies on the full-length HBV genomes are required to determine genome evolution of HBV among infected Iranian blood donors
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BACKGROUND: Although a marked proportion of thalassemic patients acquire Torque teno virus (TTV) through blood transfusion, its clinical importance is unclear. This study was designed to investigate the clinical importance of TTV infection in thalassemic patients with and without hepatitis C virus (HCV) co-infection in Iran. METHODS: In this case-control study, 107 thalassemic patients on chronic transfusion and 107 healthy individuals were selected. According to HCV and TTV infection status (detected by semi-nested PCR), patients were categorized into 4 groups: TTV and HCV negative, TTV positive, HCV positive, and TTV and HCV positive. Blood ferritin, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels in these 4 groups were assessed. RESULTS: Approximately half of the thalassemic patients (50.5%) and 27.1% of controls had TTV infection. Thalassemic patients had a greater chance of TTV infection compared to the control group with a sex-adjusted OR of 4.13 (95% CI=2.28-8.13). The increased levels of ALT, AST, and ferritin in the TTV and HCV-infected group were not significantly different from those in the TTV and HCV negative group. Co-infection with TTV and HCV did not significantly increase ALT, AST, and ferritin levels compared to infection with TTV alone. CONCLUSION: Although common in thalassemic patients, TTV infection appears to have a negligible role in increasing the severity of liver disease, even when co-infection with HCV occurs.