Engineered ClearColi™-derived outer membrane vesicles as functional carriers for development of HIV-1 therapeutic vaccine candidate.

Bacteria-derived outer membrane vesicles (OMVs) can be engineered to incorporate foreign antigens. This study explored the potential of ClearColi™-derived OMVs as a natural adjuvant and a carrier (recombinant OMVs or rOMVs) for development of an innovative therapeutic vaccine candidate harboring HIV-1 Nef and Nef-Tat antigens. Herein, the rOMVs containing CytolysinA (ClyA)-Nef and ClyA-Nef-Tat fusion proteins were isolated from ClearColi™ strain. The presence of Nef and Nef-Tat proteins on their surface (rOMVNef and rOMVNef-Tat) was confirmed by western blotting after proteinase K treatment. Immune responses induced by Nef and Nef-Tat proteins emulsified with Montanide® ISA720 or mixed with OMVs, and also rOMVNef and rOMVNef-Tat were investigated in BALB/c mice. Additionally, the potency of splenocytes exposed to single-cycle replicable (SCR) HIV-1 virions was assessed for the secretion of cytokines in vitro. Our findings showed that the rOMVs as an antigen carrier (rOMVNef and rOMVNef-Tat) induced higher levels of IgG2a, IFN-γ and granzyme B compared to OMVs as an adjuvant (Nef + OMV and Nef-Tat + OMV), and also Montanide® ISA720 (Nef + Montanide and Nef-Tat + Montanide). Moreover, IFN-γ level in splenocytes isolated from mice immunized with rOMVNef-Tat was higher than other regimens after exposure to SCR virions. Generally, ClearColi™-derived rOMVs can serve as potent carriers for developing effective vaccines against HIV-1 infection.

A quartz crystal microbalance biosensor based on polyethylenimine-modified gold electrode to detect hepatitis B biomarker.

Biomarkers-based QCM-biosensors are suitable tools for the label-free detection of infectious diseases. In the current study, a QCM-biosensor was developed for the detection of HBsAg. Briefly, anti-HBsAg antibodies were covalently bound to the primary amines after PEI and thiolated-PEI surface modifications of gold-electrode. After RSM optimization, the statistical analysis revealed no significant difference between the immobilization yields of modified layers. Therefore, the PEI-modified QCM-biosensor was selected for further analysis. The PEI-surface was evaluated by FESEM, AFM, ATR-FTIR, and CA measurement. The surface hydrophilicity and its roughness were increased after PEI-coating. Also, FTIR confirmed the PEI-layering on the gold-surface. RSM optimization increased the antibody immobilization yield up to 80%. The QCM-biosensor showed noteworthy results with a wide dynamic range of 1-1 × 103 ng/mL, LOD of 3.14 ng/mL, LOQ of 9.52 ng/mL, and detection capability in human-sera, which were comparable with the ELISA. The mean accuracy of the QCM-biosensor was obtained at 91% when measured by the spike recovery test using human-sera. The biosensor was completely regenerated using 50 mM NaOH and 1% SDS. The benefits provided by the developed biosensor such as broad dynamic range, sensitivity, selectivity, stability, regenerate ability, and low cost suggest its potential application for the non-invasive and timely monitoring of HBV-biomarker.

Association between serum inflammatory parameters and the disease severity in COVID-19 patients.

OBJECTIVE: Most patients infected with the novel coronavirus (SARS-CoV-2), as the causative agent of COVID-19 disease, show mild symptoms, but some of them develop severe illness. The purpose of this study was to analyze the blood markers of COVID-19 patients and to investigate the correlation between serum inflammatory cytokines and the disease severity. METHODS: In this prospective cross-sectional study, 50 patients with COVID-19 and 20 patients without COVID-19 were enrolled. According to ICU admission criteria, patients were divided into two groups of non-severe and severe. Differences in the serum levels of C-reactive protein (CRP), IL-6, and TNF-α, as well as erythrocyte sedimentation rate (ESR), lymphocytes (LYM) count, and neutrophils (NEU) count between the two groups were determined and analyzed. RESULTS: Out of the 50 patients with COVID-19, 14 were diagnosed as severe cases. There was no significant difference between the two groups of COVID-19 patients in terms of gender and age. Blood tests of COVID-19 patients showed a significant decrease and increase in NEU and LYM counts, respectively. There were significant differences in the serum levels of IL-6, TNF-α, and CRP between the severe and non-severe groups, which were higher in the severe group. Also, there was a significant correlation between the disease severity and CRP with ESR (r = 0.79), CRP with IL-6 (r = 0.74), LYM with NEU (r = -0.97), and ESR with TNF-α (r = 0.7). CONCLUSION: The findings of this study, as the first study in Iran, suggest that the levels of IL-6, TNF-α, ESR, and CRP could be used to predict the severity of COVID-19 disease.

No evidence of occult HBV infection in population born after mass vaccination.

Despite access to efficient hepatitis B virus (HBV) vaccine and universal immunization schedules, HBV infection remains a global health concern. HBV infection has decreased by this program. Nevertheless, breakthrough infections occur due to generation of occult HBV infection (OBI) and surface gene mutants in the immunized population. We aimed to determine the presence of OBI in a population born after initiation of nationwide HBV vaccination in Tehran, Iran. A HBV mass vaccination schedule was launched in Iran in 1993. For this study, we enrolled 1120 cases younger than 24 years. ELISA was applied to evaluate the presence of HBsAg, anti-HBs and anti-HBc. HBV-DNA presence was determined in all HBsAg-negative cases using nested polymerase chain reaction. The prevalence of HBsAg, anti-HBc and anti-HBs was 0.1, 0.54 and 39.9% respectively. Out of 6 anti-HBc-positive individuals, 4 cases also had anti-HBs. One case revealed HBsAg co-existence and the other one showed isolated anti-HBc. HBV-DNA was not detected in HBsAg-negative specimens. A very low prevalence of HBsAg and isolated anti-HBc was observed and no occult HBV infection was detected. It seems that evasion mutants are not a potential threat for HBV universal immunization efficacy in the vaccinated population.

Novel delivery based anionic linear globular dendrimerg2-zidovudine nano-conjugate significantly decreased retroviral activity.

Human diseases like viral organisms for example, hepatitis, HIV and etc., attack the health and caused large mortality in populations by many years. So finding novel delivery vehicles based antiviral drugs employing nano-materials is of high universal interest. In current approach a very biocompatible biodegradable nano-biopolymer anionic linear globular dendrimer second generation G2 was elaborately conjugated to a well-known anti-HIV drug Azidovudine and thereafter was characterized by different analytical techniques like AFM, Zeta sizer, 1HNMR, FTIR and LC-Mass spectroscopy. Then, Anionic Linear Globular DendrimerG2-Zidovudine Nano-Conjugate was assessed on human normal cells (toxicity assay by XTT test) and also HIV cell model and the results showed that Anionic Linear Globular DendrimerG2-Zidovudine Nano-Conjugate Significantly Decreased Retroviral Activity without any human cell toxicity respectively. Based on current experimental data such nano-compositions is proposed for further in vivo anti-HIV assays as well.

In vitro effect of branched polyethyleneimine (bPEI) on cells infected with human immunodeficiency virus: enhancement of viral replication.

Polyethyleneimine (PEI) is a chemical compound that used is as a carrier in gene therapy/delivery. Some studies have investigated the microbicidal potential and antiviral activity (prophylactic or therapeutic) of PEI and its derivatives. The aim of this study was to investigate the effect of branched polyethyleneimine (bPEI) on human immunodeficiency virus (HIV) replication. Infected cells were treated with bPEI for 36 hours, and the concentration of the viral protein P24 (as a virus replication marker) was determined in cell culture supernatants. This study indicated that bPEI increased HIV replication and decreased the viability of infected cells through cytotoxicity. The toxicity of bPEI its association with and cell death (apoptosis, autophagy and necrosis) have been reported in several studies. To investigate bPEI-induced cytotoxicity, we examined apoptosis and autophagy in cells treated with bPEI, and a significant increase in HIV viral load, the P24 antigen level, autophagy, and necrosis observed. Thus, treatment with bPEI leads to cytotoxicity and higher HIV virus yield.

Inherent anti-HIV activity of biocompatible anionic citrate-PEG-citrate dendrimer.

The development of new combinations to empower better protection against HIV infection is particularly important. Anionic polymers can block HIV infection. In the current study, first generation (G1) and second generation (G2) novel water-soluble anionic citrate-PEG-citrate dendrimers were synthesized and characterized with Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), and dynamic light scattering (DLS) methods. After the biocompatibility of the G2 dendrimer was determined, its antiviral activity was evaluated. This function may contribute to the peripheral groups of this dendrimer (carboxylate group). In order to measure the inhibitory effect of G2 on HIV infection, both pre-treatment (treated with G2 dendrimer before HIV infection) and co-treatment (simultaneously treated with G2 dendrimer and HIV infection) were used in vitro. The results showed the good synthesis of the G2 dendrimer, and the dendrimer showed antiviral properties (ICC50:0.4 mM) and low toxicity (CC50:0.6 mM) at high concentrations. A strong inhibitory effect was found when the co-treatment approach was used. This study achieved promising results which encourage the use of G2 dendrimers as anti-HIV agents.

Application of recurrent neural network for online prediction of cell density of recombinant Pichia pastoris producing HBsAg.

Artificial neural networking (ANN) seems to be a promising soft sensor for implementing current approaches of quality by design (QbD) and process analytical technologies (PAT) in the biopharmaceutical industry. In this study, we aimed to implement best-fitted ANN architecture for online prediction of the biomass amount of recombinant Pichia pastoris (P. pastoris) - expressing intracellular hepatitis B surface antigen (HBsAg) - during the fed-batch fermentation process using methanol as a sole carbon source. For this purpose, at the induction phase of methanol fed-batch fermentation, carbon evolution rate (CER), dissolved oxygen (DO), and methanol feed rate were selected as input vectors and total wet cell weight (WCW) was considered as output vector for the ANN. The obtained results indicated that after training recurrent ANN with data sets of four fed-batch runs, this toolbox could predict the WCW of the next fed-batch fermentation process at each specified time point with high accuracy. The R-squared and root-mean-square error between actual and predicted values were found to be 0.9985 and 13.73, respectively. This verified toolbox could have major importance in the biopharmaceutical industry since recombinant P. pastoris is widely used for the large-scale production of HBsAg.

Evaluation of autophagy induction on HEV 239 vaccine immune response in a mouse model.

Hepatitis E virus (HEV) infection remains a serious threat to life and productivity in developing world. Vaccine seems to be an effective, safe, and affordable approach to address HEV disease burden. The HEV genome consists of three open reading frames (ORFs). Of these, ORF2 encodes a single structural protein (pORF2) for the HEV capsid which has been studied extensively as vaccine candidates. Recently, it has been recognized that autophagy plays an important role in innate and adaptive immunity defense against intracellular pathogens. This mechanism could therefore promote a protective immune response by inducing CD4+ and CD8+ T cells. In this study, HEV 239 and Beclin1 proteins were expressed in prokaryotic host cell [Escherichia coli (BL21)]. HEV 239 protein with different formulations (+Alum, +Beclin1, and +Alum-Beclin1) were used as candidate vaccines and administrated subcutaneously in BALB/c mice on 0, 14, and 28 days. Finally, elicited cellular and humoral immunity were evaluated. Taken together, although our results indicated that mice immunized with HEV 239 protein formulated with Alum, Beclin1, and Alum + Beclin1 displayed humoral and cellular response that was not significant in comparison with each other (P > 0.05); whereas they were significant while compared with control groups (P < 0.05). A comprehensive understanding of the intricate interplay between autophagy and immune response remains to be unraveled. Further study will clear the detailed impact of autophagy manipulation to enhance vaccine efficacy and boost the immune responses against the disease. © 2018 IUBMB Life, 70(3):207-214, 2018.

Prevalence and risk factors for HBV and HCV in prisoners in Iran: a national bio-behavioural surveillance survey in 2015.

OBJECTIVES: To provide more accurate estimates of the prevalence of Hepatitis B (HBV) and Hepatitis C (HCV) and their contributing factors among prisoners in Iran. METHODS: Cross-sectional study of 6200 Iranian prisoners in 2015. Data were collected through questionnaires and interviews. HBV infection and HCV exposure status of the participants was determined by HBsAg and HCV antibodies blood tests using enzyme-linked immunosorbent assay (ELISA). Data were analysed in STATA-12. RESULT: Prevalence of HCV exposure was 9.48% (95% CI: 8.73-10.27), and prevalence of HBV was 2.48% (95% CI: 2.07-2.89) in the general prison population. In multivariate analysis, the most important risk factor for HBV was a history of drug use in lifetime (adjusted odds ratio, AOR: 1.8, 95% CI: 1.17-3.02). The main risk factors for HCV exposure were a history of drug use in lifetime (AOR: 4.08, CI: 2.56-6.27), age over 30 (AOR: 2.68, CI: 2.01-3.56), and having tattoos (AOR = 1.67, CI: 1.35-2.07). CONCLUSION: Although vaccination is used to control HBV among prisoners, prevalence of HCV exposure is alarming in the prison population of Iran, especially among people who inject drugs. Eliminating viral hepatitis in Iran by 2030 requires a national commitment and rapid measures for targeting this high-risk group. Given the increased efficiency of HCV treatment in recent years, prisons provide an opportunity to access patients for treatment.

Comparison of antiretroviral drug resistance among treatment-naive and treated HIV-infected individuals in Shiraz, Iran.

The use of anti-retroviral therapy has been effective in controlling the spread of HIV-1, and has prolonged life expectancy, but this success can be affected by the emergence of drug resistance. The main goal of this study was to investigate drug resistance in the reverse transcriptase (RT), and protease (PR) genes among HIV-1 infected individuals. We systematically selected 59 HIV-1 infected individuals from Shiraz Voluntary Counseling and Testing Center (29 treatment- naïve and 30 treated). In this study intravenous drug users older than 18 were included in this study. Using specific primers, nested RT-PCR was performed on RNA extracted from patient samples. The genes targeted for RT and PCR were successfully amplified and sequenced. The sequences of these two genes were compared with mutations related to drug resistance against nucleotide reverse transcriptase inhibitors (NRTI), non-nucleotide reverse transcriptase inhibitors (NNRTI) and protease inhibitors (PI) using the latest database from the International AIDS society - USA, Stanford University, and the patterns were recorded. Among treatment-naïve, the detected NRTI and NNRTI resistance mutations were V179T, V75 M and E138A. V179T causes high level resistance to Efavirenze and Nevirapin. V75 M causes intermediate resistance to Stavudine. Regarding NRTI and NNRTI resistance mutations among treated patients, the most frequent mutation (7%) was M184 V, which causes high level resistance to zidovudin and emtricitabine. The interesting result from this study was the detection of NRTI and NNRTI resistance mutations before the initiation of treatment, which signifies the transmission of resistant strains of virus between individuals. This mutation highlights the importance of drug resistance HIV-1 genotyping before commencing treatment.

HIV-1 Vpr Protein Induces Proteasomal Degradation of Chromatin-associated Class I HDACs to Overcome Latent Infection of Macrophages.

Mechanisms underlying HIV-1 latency remain among the most crucial questions that need to be answered to adopt strategies for purging the latent viral reservoirs. Here we show that HIV-1 accessory protein Vpr induces depletion of class I HDACs, including HDAC1, 2, 3, and 8, to overcome latency in macrophages. We found that Vpr binds and depletes chromatin-associated class I HDACs through a VprBP-dependent mechanism, with HDAC3 as the most affected class I HDAC. De novo expression of Vpr in infected macrophages induced depletion of HDAC1 and 3 on the HIV-1 LTR that was associated with hyperacetylation of histones on the HIV-1 LTR. As a result of hyperacetylation of histones on HIV-1 promotor, the virus established an active promotor and this contributed to the acute infection of macrophages. Collectively, HIV-1 Vpr down-regulates class I HDACs on chromatin to counteract latent infections of macrophages.

Smart bomb AS1411 aptamer-functionalized/PAMAM dendrimer nanocarriers for targeted drug delivery in the treatment of gastric cancer.

Chemotherapy, a conventional method assessed in recent oncology studies, poses numerous problems in the clinical environment. To overcome the problems inherent in chemotherapy, an intelligent drug delivery system has come to the forefront of cancer therapeutics. In this study, we designed a dendrimer-based pharmaceutical system together with a single-stranded AS1411 aptamer (APTAS1411 ) as a therapeutic strategy. The polyamidoamine (PAMAM)-polyethylene glycol (PEG) complex was then conjugated with the AS1411 aptamer and confirmed by atomic-force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) .In this study, we show that the conjugated PAMAM-PEG-APTAS1411 complex dramatically increased PAMAM-PEG-5-FU uptake by MKN45 gastric cancer cells. We also demonstrated both the stability of the nanoparticle-5-FU-APTAS1411 complex, by thin layer chromatography (TLC), and an increase in 5-fluorouracil (5-FU) accumulation in the vicinity of cancerous tumors. This smart drug delivery system is capable of effectively transferring 5-FU to MKN45 gastric cancer cells in consistent and without toxic effects.

HIV-1 Vpr Protein Enhances Proteasomal Degradation of MCM10 DNA Replication Factor through the Cul4-DDB1[VprBP] E3 Ubiquitin Ligase to Induce G2/M Cell Cycle Arrest.

Human immunodeficiency virus type 1 Vpr is an accessory protein that induces G2/M cell cycle arrest. It is well documented that interaction of Vpr with the Cul4-DDB1[VprBP] E3 ubiquitin ligase is essential for the induction of G2/M arrest. In this study, we show that HIV-1 Vpr indirectly binds MCM10, a eukaryotic DNA replication factor, in a Vpr-binding protein (VprBP) (VprBP)-dependent manner. Binding of Vpr to MCM10 enhanced ubiquitination and proteasomal degradation of MCM10. G2/M-defective mutants of Vpr were not able to deplete MCM10, and we show that Vpr-induced depletion of MCM10 is related to the ability of Vpr to induce G2/M arrest. Our study demonstrates that MCM10 is the natural substrate of the Cul4-DDB1[VprBP] E3 ubiquitin ligase whose degradation is regulated by VprBP, but Vpr enhances the proteasomal degradation of MCM10 by interacting with VprBP.

Recombinant C-terminal 311 amino acids of HapS adhesin as a vaccine candidate for nontypeable Haemophilus influenzae: A study on immunoreactivity in Balb/C mouse.

Hap, an auto-transporter protein, is an antigenically conserved adhesion protein which is present on both typeable and nontypeable Haemophilus influenzae. This protein has central role in bacterial attachment to respiratory tract epithelial cells. A 1000bp C-terminal fragment of Hap passenger domain (HapS) from nontypeable Haemophilus influenzae was cloned into a prokaryotic expression vector, pET-24a. BALB/c mice were immunized subcutaneously with purified rC-HapS. Serum IgG responses to purified rC-HapS, serum IgG subclasses were determined by ELISA and functional activity of antibodies was examined by Serum Bactericidal Assay. The output of rC-HapS was approximately 62% of the total bacterial proteins. Serum IgG responses were significantly increased in immunized group with rC-HapS mixed with Freund's adjuvant in comparison with control groups. Analysis of the serum IgG subclasses showed that the IgG1 subclass was predominant after subcutaneous immunization in BALB/c mice (IgG2a/IgG1 < 1). The sera from rC-HapS immunized animals were strongly bactericidal against nontypeable Haemophilus influenzae. These results suggest that rC-HapS may be a potential vaccine candidate for nontypeable Haemophilus influenzae.

Low prevalence of hepatitis B vaccine escape mutants among individuals born after the initiation of a nationwide vaccination program in Iran.

A nationwide hepatitis B virus (HBV) vaccination program for neonates was launched in Iran in 1993. Despite the success of this program, concern about its long-term success still remains, because breakthrough infections due to emergence of surface mutants have been reported in immunized children. We aimed to evaluate the seroprevalence of HBV and vaccine escape mutants among individuals born after the initiation of the nationwide vaccination program in Iran. This study included 1115 participants younger than 23 years old, with 223 in each age cohort. The presence of HBsAg, anti-HBs and anti-HBc was evaluated using an ELISA kit. HBV-DNA levels were measured in anti-HBc and/or HBsAg-positive subjects. PCR products were sequenced and mutations were identified. The overall HBsAg prevalence was 0.27 %. Anti-HBs and anti-HBc positive rates were 48 % and 0.18 %, respectively. Two individuals were positive for anti-HBc, one of whom was also positive for HBsAg, and the other was positive for anti-HBc only. HBV DNA was detected in three out of four anti-HBc-and /or HBsAg-positive subjects. An I195M mutation within the S gene was detected in two of the three HBV-DNA-positive cases. A very low prevalence of HBsAg and isolated anti-HBc were found in this study. The I195M mutation found in the surface gene could have been induced by immune pressure. Although the number of ''vaccine escape'' mutants found in this cohort was low, ongoing surveillance of breakthrough infections and escape mutants is still needed.

Evaluation of Truncated HCV-NS3 Protein for Potential Applications in Immunization and Diagnosis.

BACKGROUND: Hepatitis C virus infection is one of global health concern. No vaccine is available so far and nonstructural protein 3 (NS3) is one of the main target antigens for developing studies on therapeutic vaccine and diagnostic application. In the current study, we expressed a truncated recombinant HCV-NS3 protein under native condition and evaluated its potential applications in immunization and diagnosis. METHODS: The recombinant pET-NS3 containing a truncated form of HCV NS3 region was constructed, confirmed by sequencing reactions, and expressed into E.coli BL21-DE3 strain. The expressed protein was purified by affinity chromatography under native condition. Characterization of diagnostic value and immunogenicity of this recombinant protein were analyzed by using an indirect ELISA method. RESULTS: Our data showed that a truncated NS3 which contains the immunodominant region of this protein was successfully expressed and purified with a high yield of 3 mg/L. Our data showed that the immunogenicity of this truncated protein can induce a specific humoral response, as well as the usage for screening of HCV positive blood samples. CONCLUSIONS: Altogether, the present study provides a simple and efficient system for protein expression and purification of an immunodominant region of NS3-HCV in native conformation and its potential application for diagnosis and vaccine development in future.

Impact of TGF-ß1 Gene Polymorphism (rs1800469) on Treatment Response to Pegylated Interferon/Ribavirin in Iranian Patients with Hepatitis C.

BACKGROUND: Hepatitis C virus as a major cause of chronic liver disease affects more than 170 million people worldwide. Recent studies have claimed that single nucleotide polymorphisms (SNPs) for the transforming growth factor-ß1 (TGF-ß1) gene were strongly associated with the antiviral treatment response. Thus, the present study aimed at the determination of distribution of the rs1800469 (C/T) polymorphism among Iranian with chronic hepatitis C. METHODS: A total of 165 blood samples including 68 SVR positive and 21 non-responder samples from individuals suffering chronic hepatitis C and also 76 healthy individual controls were analyzed in this cross-sectional study. DNA was isolated from the samples using a DNA extraction standard kit. Then the frequency of the polymorphism was analyzed using PCR-RFLP method. Eventually, the products of interest were detected on 2.5% agarose gel electrophoresis. RESULTS: The distribution of the C/T polymorphism between healthy individuals and patients were obtained as TT: 22.4%, TC: 46%, CC: 31.6%, and TT: 19.1%, TC: 48.3%, CC: 32.6%, respectively. Furthermore, the CC genotype was identified in 20 patients of whom 68 achieved SVR, while the CT heterozygous was found in 43 patients and SVR was achieved in 38. Finally, the TT was detected in 17 patients, and 7 patients did not achieve SVR. CONCLUSIONS: We observed a significant difference of C allele frequency with SVR as compared to the T allele among patients (p = 0.064). On the other hand, there is no correlation between the polymorphism and susceptibility to HCV infection. However, further studies with more samples seem to be necessary.

Correlation Study Between IL-28B Gene Polymorphism (rs8099917SNP) and Sustained Virological Response in Iranian Patients with Chronic Hepatitis C.

BACKGROUND: The current standard treatment for hepatitis C is a combination of pegylated interferon alpha and ribavirin (peg-IFNα/RBV). Recent studies have shown that single nucleotide polymorphisms (SNPs) near the interleukin 28B (IL28B) gene coding for IFN-λ3 were associated with the antiviral treatment response. Therefore, in this study, we determined the distribution of the rs8099917 (T/G) polymorphism with sustained virological response (SVR) to chronic hepatitis C virus infection among Iranian patients. METHODS: This cross-sectional study was performed on 150 blood samples based on 93 patients with chronic HCV genotypes 1 and 3 including 71 SVR positive, 22 negative, and 57 healthy individual controls. DNA was extracted from the samples and the frequency of the polymorphism was analyzed the using PCR-RFLP method. Finally, the products were detected on 3.5% agarose gel electrophoresis. RESULTS: The analysis of the data for G/T polymorphism showed that the GG genotype was identified in 6 patients of 71 who achieved SVR, while the GT heterozygous was found in 33 patients and SVR was achieved in 19. Finally, the TT was detected in 53 patients and 7 patients were resistant to treatment. CONCLUSIONS: The results showed significant effects of G allele carriers on susceptibility to HCV infection com-pared to the other allele (T) in our studied population (p = 0.013, OR = 2.23, 95% CI = 1.18-4.21), but we did not find a significant correlation for SVR to therapy in patients with genotype TT (p = 0.055, OR = 0.48, 95% CI = 0.23-1.01). However, further studies with more samples are necessary.

Expression of HCV Alternative Reading Frame Protein (Core+1/F) in Baculovirus Expression System and its Evaluation for Assessment of Specific Anti-core+1 Antibody in Iranian HCV Infected Patients.

BACKGROUND: Hepatitis C virus (HCV) genome contains an overlapping reading frame which results in alternative core protein (ARFP). Baculovirus expression system was used as a powerful eukaryotic vector system to express core+1/F protein for the first time. This recombinant core+1/F protein was used to assess the anti-core+1 antibody in anti-HCV drug resistant and sustained virologic response (SVR) patients. METHODS: The core+1 coding sequence from HCV genotype 1 was designed and synthesized in pUC57 vector. It was subcloned into baculovirus donor plasmid pFastBacTM HTA and transposed into baculovirus shuttle vector (bacmid) to transfect Sf9 cells. Recombinant core+1 protein was purified using Ni-NTA agarose under native condition and verified using SDS-PAGE electrophoresis and Western blotting. An enzyme-linked immunosorbent assay (ELISA) was developed using this purified protein to assess anti-core+1 antibody in 28 anti-HCV drug resistant patients and in 34 patients with sustained virologic response (SVR) in comparison with 31 healthy volunteers used as the negative control. RESULTS: Expression of HCV core+1 protein in Sf9 cells was confirmed by using SDS-PAGE and Western blotting. Antibody titer against core+1 protein in anti-HCV drug resistant patients was significantly higher than that in both the healthy volunteers and SVR patients (p < 0.0001). CONCLUSIONS: HCV core+1 protein was expressed successfully in a baculovirus expression system in high yield in order to develop an ELISA to assess the anti-core+1 antibody. Further studies are needed to reveal the potential application of core+1 protein in anti-HCV treatment prognosis.