Critical aggregation concentration can be a predictor of doxorubicin delivery performance of self-assembling amphiphilic peptides with different hydrophobic tails

Amphiphilic peptides hold great potential as drug delivery systems. A popular peptide design approach has been to place amino acids in the peptide sequence based on their known properties. On the other hand, the directed discovery approach aims to screen a sequence space for a desired property. However, screening amphiphilic peptides for desirable drug delivery properties is not possible without a quantity that is predictive of these properties. We studied the predictive power of critical aggregation concentration (CAC) values on the drug delivery performance of a series of amphiphilic peptides with different hydrophobic tails and close CAC values. The CAC values were predicted by our previously developed model and doxorubicin was used as a model hydrophobic drug. All peptides showed close drug loading, entrapment efficiency, and release profile. They also formed similar spherical particles by assembling in reverse β-sheet arrangements regardless of drug presence. Moreover, the assembled particles were able to accumulate doxorubicin inside ordinary as well as drug-resistant breast cancer cells and enhance its toxicity up to 39 and 17 folds, respectively. It can be concluded that similar drug delivery properties displayed by the peptides can be attributed to their similar hydrophilic-lipophilic balance as reflected in their close CAC values.

Nona-Arginine Mediated Anti-E6 ShRNA Delivery Suppresses the Growth of Hela Cells in vitro

Background

The E6 oncoprotein of HPV plays a crucial role in promoting cell proliferation and inhibiting apoptosis, leading to tumor growth. Non-viral vectors such as nona-arginine (R9) peptides have shown to be potential as carriers for therapeutic molecules. This study aimed to investigate the efficacy of nona-arginine in delivering E6 shRNA and suppressing the E6 gene of HeLa cells in vitro.

Methods

HeLa cells carrying E6 gene were treated with a complex of nona-arginine and E6 shRNA. The complex was evaluated using gel retardation assay and FESEM microscopy. The optimal N/P ratio for R9 peptide to transfect HeLa cells with luciferase gene was determined. Relative real-time PCR was used to evaluate the efficiency of mRNA suppression efficiency for E6 shRNA, while the effect of E6 shRNA on cell viability was measured using an MTT assay.

Results

The results indicated that R9 efficiently binds to shRNA and effectively transfects E6 shRNA complexes at N/P ratios greater than 30. Transfection with R9 and PEI complexes resulted in a significant toxicity compared to the scrambled plasmid, indicating selective toxicity for HeLa cells. Real-time PCR confirmed the reduction of E6 mRNA expression levels in the cells transfected with anti-E6 shRNA.

Conclusion

The study suggests that R9 is a promising non-viral gene carrier for transfecting E6 shRNA in vitro, with significant transfection efficiency and minimal toxicity.

Nona-Arginine Mediated Anti-E6 ShRNA Delivery Suppresses the Growth of Hela Cells in vitro

Background

The E6 oncoprotein of HPV plays a crucial role in promoting cell proliferation and inhibiting apoptosis, leading to tumor growth. Non-viral vectors such as nona-arginine (R9) peptides have shown to be potential as carriers for therapeutic molecules. This study aimed to investigate the efficacy of nona-arginine in delivering E6 shRNA and suppressing the E6 gene of HeLa cells in vitro.

Methods

HeLa cells carrying E6 gene were treated with a complex of nona-arginine and E6 shRNA. The complex was evaluated using gel retardation assay and FESEM microscopy. The optimal N/P ratio for R9 peptide to transfect HeLa cells with luciferase gene was determined. Relative real-time PCR was used to evaluate the efficiency of mRNA suppression efficiency for E6 shRNA, while the effect of E6 shRNA on cell viability was measured using an MTT assay.

Results

The results indicated that R9 efficiently binds to shRNA and effectively transfects E6 shRNA complexes at N/P ratios greater than 30. Transfection with R9 and PEI complexes resulted in a significant toxicity compared to the scrambled plasmid, indicating selective toxicity for HeLa cells. Real-time PCR confirmed the reduction of E6 mRNA expression levels in the cells transfected with anti-E6 shRNA.

Conclusion

The study suggests that R9 is a promising non-viral gene carrier for transfecting E6 shRNA in vitro, with significant transfection efficiency and minimal toxicity.

Fiber manipulation and post-assembly nanobody conjugation for adenoviral vector retargeting through SpyTag-SpyCatcher protein ligation

For adenoviruses (Ads) to be optimally effective in cancer theranostics, they need to be retargeted toward target cells and lose their natural tropism. Typically, this is accomplished by either engineering fiber proteins and/or employing bispecific adapters, capable of bonding Ad fibers and tumor antigen receptors. This study aimed to present a simple and versatile method for generating Ad-based bionanoparticles specific to target cells, using the SpyTag-SpyCatcher system. The SpyTag peptide was inserted into the HI loop of fiber-knob protein, which could act as a covalent anchoring site for a targeting moiety fused to a truncated SpyCatcher (SpyCatcherΔ) pair. After confirming the presence and functionality of SpyTag on the Ad type-5 (Ad5) fiber knob, an adapter molecule, comprising of SpyCatcherΔ fused to an anti-vascular endothelial growth factor receptor 2 (VEGFR2) nanobody, was recombinantly expressed in Escherichia coli and purified before conjugation to fiber-modified Ad5 (fmAd5). After evaluating fmAd5 detargeting from its primary coxsackie and adenovirus receptor (CAR), the nanobody-decorated fmAd5 could be efficiently retargeted to VEGFR2-expressing 293/KDR and human umbilical vein endothelial (HUVEC) cell lines. In conclusion, a plug-and-play platform was described in this study for detargeting and retargeting Ad5 through the SpyTag-SpyCatcher system, which could be potentially applied to generate tailored bionanoparticles for a broad range of specific targets; therefore, it can be introduced as a promising approach in cancer nanotheranostics.

Bi/tri-specific antibodies (HN-Fc-CD16 and HN-Fc-IL-15-CD16) cross-linking natural killer (NK)-CD16 and Newcastle Disease Virus (NDV)-HN, enhanced NK activation for cancer immunotherapy

Cancer/tumor cells infected with the "avian paramyxovirus Newcastle Disease Virus (TC-NDV)" express the viral hemagglutinin-neuraminidase (HN) on the cell surface that is used as both the danger signal and anchor for bi/tri-specific antibodies (bs/tsAbs).We constructed a bs-Ab (HN-Fc-CD16) that bindsto HN and natural killer (NK)-CD16 receptor (FcgRIII)and a ts-Ab (HN-Fc-IL15-CD16) harbouring NK-activating cytokine "IL-15" within the bs-Ab.In silicoand computational predictions indicated proper exposure of both Abs in bs/tsAbs.Properbinding of thebi/tsAbstoHN on surface of TC-NDVandCD16⁺-cells was demonstrated by flow cytometry.The bi/tsAbstriggeredspecificcytotoxicity of NK cells againstTC-NDVand elicited substantial IFN-γproduction by activated NK cells(higher for ts-Ab) that sound promising for cancer immunotherapy purposes.

Novel Descriptors Derived from the Aggregation Propensity of Di- and Tripeptides Can Predict the Critical Aggregation Concentration of Longer Peptides

Self-assembling amphiphilic peptides have recently received special attention in medicine. Nonetheless, testing the myriad of combinations generated from at least 20 coded and several hundreds of noncoded amino acids to obtain candidate sequences for each application, if possible, is time-consuming and expensive. Therefore, rapid and accurate approaches are needed to select candidates from countless combinations. In the current study, we examined three conventional descriptor sets along with a novel descriptor set derived from the simulated aggregation propensity of di- and tripeptides to model the critical aggregation concentration (CAC) of amphiphilic peptides. In contrast to the conventional descriptors, the radial kernel model derived from the novel descriptor set accurately predicted the critical aggregation concentration of the test set with a residual standard error of 0.10. The importance of aromatic side chains, as well as neighboring amino acids in the self-assembly, was emphasized by analysis of the influential descriptors. The addition of very long peptides (70-100 residues) to the data set decreased the model accuracy and changed the influential descriptors. The developed model can be used to predict the CAC of self-assembling amphiphilic peptides and also to derive rules to apply in designing novel amphiphilic peptides with desired properties.

Severe acute respiratory syndrome-coronavirus-2 spike (S) protein based vaccine candidates: State of the art and future prospects

Coronavirus disease 2019 (Covid-19) is caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) which is responsible for a global pandemic that started in late 2019 in Wuhan, China. To prevent the worldwide spread of this highly pathogenic virus, development of an effective and safe vaccine is urgently needed. The SARS-CoV-2 and SARS-CoV share a high degree of genetic and pathologic identity and share safety and immune-enhancement concerns regarding vaccine development. Prior animal studies with first generation (whole virus-based) preparations of SARS-CoV vaccines (inactivated and attenuated vaccine modalities) indicated the possibility of increased infectivity or eosinophilic infiltration by immunization. Therefore, development of second and third generation safer vaccines (by using modern vaccine platforms) is actively sought for this viral infection. The spike (S) protein of SARS-CoVs is the main determinant of cell entry and tropism and is responsible for facilitating zoonosis into humans and sustained person-to-person transmission. Furthermore, 'S' protein contains multiple neutralizing epitopes that play an essential role in the induction of neutralizing antibodies (nAbs) and protective immunity. Moreover, T-cell responses against the SARS-CoV-2 'S' protein have also been characterized that correlate to the IgG and IgA antibody titres in Covid-19 patients. Thus, S protein is an obvious candidate antigen for inclusion into vaccine platforms against SARS-CoV-2 viral infection. This manuscript reviews different characteristics of S protein, its potency and 'state of the art' of the vaccine development strategies and platforms using this antigen, for construction of a safe and effective SARS-CoV-2 vaccine.

Expression and Purification of a Bispecific Antibody against CD16 and Hemagglutinin Neuraminidase (HN) in E. Coli for Cancer Immunotherapy

Background

: Immunotherapy of cancer by bispecific antibodies (bsAb) is an attractive approach for retargeting immune effector cells including natural killer (NK) cells to the tumor if the proper expression and purification of the bsAb for such applications could be addressed. Herein, we describe E. coli expression of a recombinant bsAb (bsHN-CD16) recognizing NK-CD16 and hemagglutinin neuraminidase (HN) of Newcastle Disease Virus (NDV). This bsAb might be efficient for ex vivo stimulation of NK cells via coupling to HN on the surface of the NDV-infected tumor cells.

Methods

A bsAb-encoding pcDNA3.1 vector (anti-HN scFv-Fc-anti-CD16 scFv) was used as a template, and the scFv segments (after enzymatic digestion and cutting of the Fc part) were rejoined to construct the Fc-deprived bsAb (anti-HN scFv-anti-CD16 scFv; bsHN-CD16). The constructed bsHN-CD16 was inserted into the HindIII and BamHI site of the T7 promoter-based pET28a plasmid. Following restriction analyses and DNA sequencing to confirm the cloning steps, bsHN-CD16 encoding pET28a was transformed into the E. coli (Rosetta DE3 strain), induced for protein expression by IPTG, and the protein was purified under native condition by Ni/NTA column using imidazole.

Results

Analyses by SDS-PAGE and Western Blotting using Rabbit anti-human whole IgG-HRP conjugate, confirmed the expression and purification of the bsAb with the expected full size of 55 kDa and yields around 8% of the total protein.

Conclusion

Results showed efficient production of the bsAb in E. coli for future large-scale purification.

Epidemiology and Clinical Characteristics of Rotavirus and Norovirus Infections in Hospitalized Children Less Than 5 Years of Age With Acute Gastroenteritis in Tehran, Iran

Acute gastroenteritis is one of the most important causes of death in children in developing countries which cause by different enteropathogens, including bacteria, viruses, and parasites. Among these, most of the acute gastroenteritis in children are caused by viral infections mainly by rotavirus and norovirus. This study aimed to study the epidemiological and clinical status of acute gastroenteritis resulting from rotavirus and norovirus in children between June 2015 and June 2016 in Iran. A total of 211 stool specimens were collected from Ali Asghar Children's Hospital and Bahrami Children's Hospital in Tehran, from June 2015 to June 2016. The samples were screened by commercial enzyme immunoassay (EIA) Ridascreen kit and real time RT-PCR to detect rotavirus and norovirus genogroups I and II, respectively. The information on demographic and clinical manifestations was collected, and data analyzed using IBM SPSS statistics version 22. Overall, the detection rate of rotavirus was 25.6 %, and for norovirus infection, it was 17.5%. All norovirus positive specimens belonged to genogroup II. Higher rates of rotavirus infections were observed in children from 7 to 24 months, and higher rates of norovirus infections were detected in children from 1 to 12 months. Clinical symptoms were not different between rotavirus and norovirus case-patients. The present study not only highlights the importance of rotavirus and norovirus infections in Iran but also verifies the relevance of norovirus as the cause of severe gastroenteritis in children.

Oncolytic adenovirus: A tool for cancer therapy in combination with other therapeutic approaches

Cancer therapy using oncolytic viruses is an emerging area, in which viruses are engineered to selectively propagate in tumor tissues without affecting healthy cells. Because of the advantages that adenoviruses (Ads) have over other viruses, they are more considered. To achieve tumor selectivity, two main modifications on Ads genome have been applied: small deletions and insertion of tissue- or tumor-specific promoters. Despite oncolytic adenoviruses ability in tumor cell lysis and immune responses stimulation, to further increase their antitumor effects, genomic modifications have been carried out including insertion of checkpoint inhibitors and antigenic or immunostimulatory molecules into the adenovirus genome and combination with dendritic cells and chemotherapeutic agents. This study reviews oncolytic adenoviruses structures, their antitumor efficacy in combination with other therapeutic strategies, and finally challenges around this treatment approach.

Interleukin 20 Gene Polymorphism (rs1518108) is not Associated with Sustained Virological Response in Iranian Patients with Hepatitis C Virus Infection

METHODS

This case-control study, was performed on 136 blood samples based on 81 patients with chronic HCV genotypes 1 and 3 including 64 SVR positive and 17 negative and 55 healthy individual controls. DNA was isolated from the samples and the frequency of the polymorphism was analyzed using a PCR-RFLP method. Finally, the products were detected on 3.5% agarose gel electrophoresis.

RESULTS

The analysis of the data for C/T polymorphism indicated that the CC genotype was found in 19 of 64 patients who achieved SVR, while the TT genotype was detected in 3 patients and SVR was achieved in 2. Finally, heterozygous CT was identified in 53 patients and 10 patients were resistant to treatment.

CONCLUSIONS

The results did not support any significant effects of TT or CT genotypes on susceptibility to HCV infection (p = 0.935, OR = 1.031, CI = 0.464 - 2.026). Moreover, there was no significant correlation between SVR to PEG-IFN combined by ribavirin therapy in patients with genotype CC (p = 0.601, OR = 0.736, CI = 0.234 - 2.319).

Computational simulations assessment of mutations impact on streptokinase (SK) from a group G streptococci with enhanced activity - insights into the functional roles of structural dynamics flexibility of SK and stabilization of SK-μplasmin catalytic complex

Streptokinase (SK), a plasminogen activator (PA) that converts inactive plasminogen (Pg) to plasmin (Pm), is a protein secreted by groups A, C, and G streptococci (GAS, GCS, and GGS, respectively), with high sequence divergence and functional heterogeneity. While roles of some residual changes in altered SK functionality are shown, the underlying structural mechanisms are less known. Herein, using computational approaches, we analyzed the conformational basis for the increased activity of SK from a GGS (SKG132) isolate with four natural residual substitutions (Ile33Phe, Arg45Gln, Asn228Lys, Phe287Ile) compared to the standard GCS (SKC). Using the crystal structure of SK.Pm catalytic complex as main template SKC.μPm catalytic complex was modeled through homology modeling process and validated by several online validation servers. Subsequently, SKG132.μPm structure was constructed by altering the corresponding residual substitutions. Results of three independent MD simulations showed increased RMSF values for SKG132.μPm, indicating the enhanced structural flexibility compared to SKC.μPm, specially in 170 and 250 loops and three regions: R1 (149-161), R2 (182-215) and R3 (224-229). In parallel, the average number of Hydrogen bonds in 170 loop, R2 and R3 (especially for Asn228Lys) of SKG132 compared to that of the SKC was decreased. Accordingly, residue interaction networks (RINs) analyses indicated that Asn228Lys might induce more level of structural flexibility by generation of free Lys256, while Phe287Ile and Ile33Phe enhanced the stabilization of the SKG132.μPm catalytic complex. These results denoted the potential role of the optimal dynamic state and stabilized catalytic complex for increased PA potencies of SK as a thrombolytic drug.

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.

Immunization of Mice by Rotavirus NSP4-VP6 Fusion Protein Elicited Stronger Responses Compared to VP6 Alone

Due to the limitations and safety issues of the two currently approved live attenuated rotavirus (RV) vaccines "RotaTeq and Rotarix," studies on nonreplicating sources of RV vaccines and search for proper RV antigens are actively carried out. The adjuvant activity of NSP4 and highly immunogenic properties of RV VP6 protein prompted us to consider the construction of a NSP4_112-175-VP6 fusion protein and to assess the anti-VP6 IgG, IgA, and IgG subclass responses induced by Escherichia coli-derived NSP4-VP6 fusion protein compared to that of VP6 protein with/without formulation in Montanide ISA 50V2 (M50) in BALB/c mice. Results indicated to the proper expression of the fused NSP4-VP6 and VP6 proteins in E. coli. Intraperitoneal immunization by M50 formulated NSP4-VP6 fusion protein (M5+NSP4-VP6) induced the highest titration of VP6-specific IgG and IgA responses compared to the other groups. Indeed, the presence of NSP4 resulted to the induction of stronger humoral immune responses against the fused protein compared to that elicited by administration of VP6 protein alone (with/without M50 formulation), implying the adjuvant properties of NSP4 for the fused protein. Moreover, the "M50+NSP4-VP6" formulation induced higher serum IgG2a titers than IgG1 and increased Interferon-γ levels, despite unchanged interleukin-4 amounts compared to other groups, indicating Th1-oriented responses with a possible role of NSP4. In conclusion, this study further highlights the potentiality of NSP4-VP6 fusion protein as an efficient and cost-effective immunogen in the field of RV vaccine development.

Sindbis Virus-Pseudotyped Lentiviral Vectors Carrying VEGFR2-Specific Nanobody for Potential Transductional Targeting of Tumor Vasculature

Introduction of selectivity/specificity into viral-based gene delivery systems, such as lentiviral vectors (LVs), is crucial in their systemic administration for cancer gene therapy. The pivotal role of tumor-associated endothelial cells (TAECs) in tumor angiogenesis and overexpression of vascular endothelial growth factor receptor-2 (VEGFR2 or KDR) in TAECs makes them a potent target in cancer treatment. Herein, we report the development of VEGFR2-targeted LVs pseudotyped with chimeric sindbis virus E2 glycoprotein (cSVE2s). For this purpose, either sequence of a VEGFR2-specific nanobody or its natural ligand (VEGF₁₂₁) was inserted into the binding site of sindbis virus E2 glycoprotein. In silico modeling data suggested that the inserted targeting motifs were exposed in the context of cSVE2s. Western blot analysis of LVs indicated the incorporation of cSVE2s into viral particles. Capture ELISA demonstrated the specificity/functionality of the incorporated cSVE2s. Transduction of 293/KDR (expressing VEGFR2) or 293T cells (negative control) by constructed LVs followed by fluorescent microscopy and flow cytometric analyses indicated selective transduction of 293/KDR cells (30 %) by both targeting motifs compared to 293T control cells (1-2 %). These results implied similar targeting properties of VEGFR2-specific nanobody compared to the VEGF₁₂₁ and indicated the potential for transductional targeting of tumor vasculature by the nanobody displaying LVs.

Merkel cell polyomavirus IgG antibody levels are associated with progression to AIDS among HIV-infected individuals

The association of Merkel cell polyomavirus (MCP_yV) with Merkel cell carcinoma (MCC) in immunocompromised individuals has been revealed in a number of surveys. The study of MCP_yV specific antibody titers and viral loads in such patients has a great attraction for research groups interested in viral reactivation. In this cross-sectional study to evaluate MCP_yV antibody titer, DNA prevalence and viral load in peripheral blood mononuclear cells (PBMCs), we examined 205 HIV-1 infected patients and 100 un-infected controls. The HIV-1 infected patients divided into two groups (HIV/AIDS and non-AIDS) according to their CD4 status. Total IgG antibody titer against MCP_yV was analyzed by virus like particle (VLP)-based enzyme linked immunosorbent assay (ELISA). Presence of MCP_yV-DNA in subject's PBMCs was examined by quantitative real-time PCR assay. Levels of anti-MCP_yV IgG in HIV/AIDS patients were significantly higher than those in non-AIDS HIV-infected and control subjects (p value = <0.001). The prevalence rate of MCP_yV-DNA in PBMCs of HIV/AIDS, non-AIDS HIV-infected and un-infected controls were 17%, 16%, and 14% respectively. The MCP_yV viral load among the groups ranged between 0.15 to 2.9 copies/10³cells (median, 1.9 copies/10³cells), with no significant difference between the studied populations (p value = 0.3).

Prevalence of Merkel Cell Polyomavirus in Tehran: An Age-Specific Serological Study

Background

Several new types of polyomavirus have been discovered in recent years mainly because of the recent state-of-the-art detection technologies. Among the polyomaviruses, Merkel cell polyomavirus (MCPyV) has attracted the most attention because of its possible role in the etiology of Merkel cell carcinoma, a rare but lethal form of skin cancer.

Objectives

This study aimed to determine age-specific seroprevalence of MCPyV in Tehran.

Patients and Methods

In this cross-sectional study, we collected 440 serum samples from healthy individuals 2 to 78 years of age who visited the Pasteur Institute’s clinic in Tehran, Iran, using a convenience sampling strategy. We developed a virus-like particle-based enzyme-linked immunosorbent assay that uses VP1, the major capsid protein of MCPyV, to detect and quantitate serum antibodies to MCPyV. We compared the prevalence of MCPyV between males and females and across eight age groups.

Results

A total of 255 (57.9%) of the serum samples were MCPyV positive. The seroprevalence in children under 10 years of age was 25%. The seroprevalence increased to 56% over the next decade of life (10 - 19 years of age). The seroprevalence rate in males and females was 56.1% and 59.7% respectively, and a binary logistic regression showed no significant difference between males and females (P = 0.77). However, the prevalence of MCPyV increased with age (P = 0.012).

Conclusions

Our results suggest that human exposure to MCPyV occurs throughout life. The MCPyV antibody levels remained high among older adults in our population, consistent with reports from other populations.

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.

Lack of TNF-α Gene Polymorphism (rs1799724) Association with Sustained Virological Response in Iranian Patients with Chronic HCV Infection

Infection with the hepatitis C virus is a major public health concern which can lead to carcinoma and liver failure. It has been shown that single nucleotide polymorphisms can affect the level of gene activity of tumor necrosis factor (TNF) which has an important role, especially in viral infections which can lead to apaptosis of infected hepatocellular cells. We investigated the impact of three possible genotypes for rs1800629 or A/G single nucleotide polymorphism located downstream of TNFα gene promoter in groups of control (n=76) and chronic hepatitis C patients (n=89) focusing on the response to treatment among sensitive and resistant groups. Genomic DNA was extracted from 500 μl prepheral whole blood and PCR and RFLP were used to amplify the region of interest and genotyping. With statistical analyzes a p-value <0.05 was considered meaningful. There was no significant difference in distribution of the possible three genotypes among healthy individuals and patients (P=0.906, OR=1.194, CI=0.063-22.790). However, the frequency of the G allele was higher in patients whereas A allele was more common among healthy individuals (p<0.0001). Further studies with more samples appears to be necessary.

Preparation and evaluation of inhalable itraconazole chitosan based polymeric micelles

Background

This study evaluated the potential of chitosan based polymeric micelles as a nanocarrier system for pulmonary delivery of itraconazole (ITRA).

Methods

Hydrophobically modified chitosan were synthesized by conjugation of stearic acid to the hydrophilic depolymerized chitosan. FTIR and ¹HNMR were used to prove the chemical structure and physical properties of the depolymerized and the stearic acid grafted chitosan. ITRA was entrapped into the micelles and physicochemical properties of the micelles were investigated. Fluorescence spectroscopy, dynamic laser light scattering and transmission electron microscopy were used to characterize the physicochemical properties of the prepared micelles. The in vitro pulmonary profile of polymeric micelles was studied by an air-jet nebulizer connected to a twin stage impinger.

Results

The polymeric micelles prepared in this study could entrap up to 43.2±2.27 μg of ITRA per milliliter. All micelles showed mean diameter between 120–200 nm. The critical micelle concentration of the stearic acid grafted chitosan was found to be 1.58×10^-2 mg/ml. The nebulization efficiency was up to 89% and the fine particle fraction (FPF) varied from 38% to 47%. The micelles had enough stability to remain encapsulation of the drug during nebulization process.

Conclusions

In vitro data showed that stearic acid grafted chitosan based polymeric micelles has a potential to be used as nanocarriers for delivery of itraconazole through inhalation.

Drying of a plasmid containing formulation: chitosan as a protecting agent

BACKGROUND

The purpose of the study. Along with research on development of more efficient gene delivery systems, it is necessary to search on stabilization processes to extend their active life span. Chitosan is a nontoxic, biocompatible and available gene delivery carrier. The aim of this study was to assess the ability of this polymer to preserve transfection efficiency during spray-drying and a modified freeze-drying process in the presence of commonly used excipients.

METHOD

Molecular weight of chitosan was reduced by a chemical reaction and achieved low molecular weight chitosan (LMWC) was complexed with pDNA. Obtained nanocomplex suspensions were diluted by solutions of lactose and leucine, and these formulations were spray dried or freeze dried using a modified technique. Size, polydispersity index, zeta potential, intensity of supercoiled DNA band on gel electrophoresis, and transfection efficiency of reconstituted nanocomplexes were compared with freshly prepared ones.

RESULTS AND MAJOR CONCLUSION

Size distribution profiles of both freeze dried, and 13 out of 16 spray-dried nanocomplexes remained identical to freshly prepared ones. LMWC protected up to 100% of supercoiled structure of pDNA in both processes, although DNA degradation was higher in spray-drying of the nanocomplexes prepared with low N/P ratios. Both techniques preserved transfection efficiency similarly even in lower N/P ratios, where supercoiled DNA content of spray dried formulations was lower than freeze-dried ones. Leucine did not show a significant effect on properties of the processed nanocomplexes. It can be concluded that LMWC can protect DNA structure and transfection efficiency in both processes even in the presence of leucine.

Drying of a plasmid containing formulation: chitosan as a protecting agent

Background

Along with research on development of more efficient gene delivery systems, it is necessary to search on stabilization processes to extend their active life span. Chitosan is a nontoxic, biocompatible and available gene delivery carrier. The aim of this study was to assess the ability of this polymer to preserve transfection efficiency during spray-drying and a modified freeze-drying process in the presence of commonly used excipients.

Methods

Molecular weight of chitosan was reduced by a chemical reaction and achieved low molecular weight chitosan (LMWC) was complexed with pDNA. Obtained nanocomplex suspensions were diluted by solutions of lactose and leucine, and these formulations were spray dried or freeze dried using a modified technique. Size, polydispersity index, zeta potential, intensity of supercoiled DNA band on gel electrophoresis, and transfection efficiency of reconstituted nanocomplexes were compared with freshly prepared ones.

Results and conclusion

Size distribution profiles of both freeze dried, and 13 out of 16 spray-dried nanocomplexes remained identical to freshly prepared ones. LMWC protected up to 100% of supercoiled structure of pDNA in both processes, although DNA degradation was higher in spray-drying of the nanocomplexes prepared with low N/P ratios. Both techniques preserved transfection efficiency similarly even in lower N/P ratios, where supercoiled DNA content of spray dried formulations was lower than freeze-dried ones. Leucine did not show a significant effect on properties of the processed nanocomplexes. It can be concluded that LMWC can protect DNA structure and transfection efficiency in both processes even in the presence of leucine.