Comparison of the inhibitory and stimulatory effects of Core and NS3 candidate HCV vaccines on the cellular immune response.

Currently, hepatitis C virus (HCV) infects nearly 3% of the global population, the majority of whom are chronically infected; however, hepatitis C vaccines are still in the developmental stage. Numerous studies suggest that the spontaneous resolution of HCV infection and the design of its vaccine are reliant on vital contributions from CTL cell responses and T regulatory cells. Multiple researchers have identified both Core and nonstructural protein 3 (NS3) proteins as crucial immune genes and potential candidates for HCV DNA vaccine design. In this study, Core and NS3 were subcloned and inserted into pcDNA3.1 to construct HCV DNA vaccines administered in mouse models. Furthermore, the effects of Core and NS3 on the induction of CTL and NK were compared in spleen mouse models using the LDH method. Additionally, flow cytometry was employed to investigate the percentage of T regulatory cells (Treg cells) and cells expressing PD-1 in the spleens of the mouse models. Our data indicated that pcDNA3.1+NS3 and pcDNA3.1+Core could enhance CTL and NK activity in mouse models. Importantly, the Treg and PD-1 analysis in mouse models revealed a substantial reduction in the proportions of CD4+/CD25+/Foxp3+ T cells and PD-1+ cells in experimental subjects treated with HCV NS3 along with 5 mg/kg of lenalidomide, utilized as a novel adjuvant, compared to those administered an equivalent dosage of lenalidomide in conjunction with HCV Core. In conclusion, our observations indicated that the NS3-HCV gene had a limited impact on the activation of inhibitory factors. Therefore, NS3 is considered a more suitable candidate for DNA vaccine design compared to Core HCV.

Relative Frequency of Blood-Borne Viruses in Hemodialysis-Dependent and Kidney Transplant Recipients in Iran.

BACKGROUND: Hemodialysis (HD) patients and kidney transplant (KT) recipients are exposed to be infected by blood-borne viruses (BBVs). Current study was conducted to evaluate the prevalence of BBVs in HD and KT patients in the whole Iranian population. METHODS: From Jan 2016 to Dec 2017, 174 hemodialysis and 139 kidney transplant recipients enrolled in this survey. After blood sampling, serum samples were detected for HBV, HCV, HCMV, HIV and HTLV antibodies. Seropositive samples confirmed by Polymerase chain reaction (PCR) method. RESULTS: Overall, 6 (3.44%) and 3 (2.15%) of hemodialysis-dependent and transplantation patients had evidence of HCV infection, whereas no patients were HIV and HBV positive, two cases (1.14%) of hemodialysis and one case (0.71%) of transplantation patients demonstrated the HTLV-1 infection. 52 (37.4%) of patients received graft were positive for HCMV antibody. In addition, our study showed a co-infection of HCMV with HCV (3 patients, 2.15%) in transplantation patients. CONCLUSION: Prevalence of BBVs infection was lower in comparison to the previous studies. The current strict infection control practices in Iran appear to be effective in limiting dialysis and related infections after transplantation. Because BBVs infections constantly occur especially in dialysis and after transplantation units, our data will be useful to build a new strategic plan for the elimination of BBVs infection in kidney therapycenters.

Lenalidomide acts as an adjuvant for HCV DNA vaccine.

Hepatitis C virus (HCV) is a blood-borne pathogen which has chronically infected people worldwide. Therefore, it is of utmost importance to design prophylactic and therapeutic vaccine in order to control HCV infection. To date, several researchers have attempted to improve the efficiency of HCV vaccine by using different adjuvants. However, a few studies have focused on the synthetic immunomodulatory drugs as adjuvants for HCV vaccine. Recently, researchers have shown that lenalidomide, which is used to treat the patients with multiple myeloma, is capable of improving the immune system factors. In this paper, two doses of lenalidomide along with pcDNA3.1+NS3 as HCV DNA vaccine were administrated in mice models and the percentage of regulatory T cells (Treg cells) and the cells with PD-1+ expression in spleen of mice model were investigated by flow cytometry method. Additionally, activities of CTL cells and NK cells were evaluated in spleen of prophylactic and therapeutic mice models via LDH method. Results of the Treg and PD-1 analysis showed that low dose of lenalidomide along with pcDNA3.1+NS3 can noticeably decrease the percentage of Treg cells and the cells with PD-1+ expression, while lenalidomide can significantly increase the CTL and NK activity in mice models. Also, results of the therapeutic mice model, in which SP2/0 cells- challenged mice were treated with 5mg/kg lenalidomide in combination with pcDNA3.1+NS3, reasonably agreed with those of the prophylactic model. Finally, it was found that lenalidomide can reduce the level of Treg cells which results in lower the cells with PD-1+ expression and subsequently higher CTL and NK cell activities. This study concluded that lenalidomide possess the characteristics of an ideal adjuvant candidate for use in combination with HCV DNA vaccine in order to promote the immune response and vaccine efficiency.

Low Dose of Lenalidomide Enhances NK Cell Activity: Possible Implication as an Adjuvant.

BACKGROUND: Lenalidomide, a synthetic immunomodulatory drug, has a wide range of features including anti-angiogenic and anti-proliferative properties. To date, researchers have shown that lenalidomide is capable of ameliorating the immune system factors and antitumor responses. Most researchers have reported that lenalidomide enhances the immune response in certain cancer patients through several pathways including the stimulation of Natural Killer cells; notwithstanding, it is still crucial to investigate the effect of lenalidomide on the activity of NK cell cytotoxicity both in vitro and in vivo. OBJECTIVE: To evaluate the in vitro impact of lenalidomide, of different doses, on NK cytotoxicity activity and an in vivo investigation to find the adjuvant behavior of lenalidomide. METHODS: NK cytotoxocity was measured with the lactate dehydrogenase (LDH) release assay via K562 cells. Lenalidomide was prepared at 1 mM, 2 mM, 4 mM and 8 mM for in vitro study. In addition, the adjuvant properties of lenalidomide were assessed in ten mice groups using NS3 HCV DNA vaccine model of antigen pcDNA3.1(+)/NS3. RESULTS: The results showed that, comparisons to other doses, 4 mMol of lenalidomide was able to noticeably increase NK cytotoxicity activity. Furthermore, the animal model indicated that lenalidomide stimulated NK cytotoxicity in vivo, augmenting it from 16.67% ± 2.07% for the control group to 38.17% ± 2.87% for the lenalidomide-treated. CONCLUSION: Treatment by lenalidomide and pcDNA3.1(+)/NS3 improves NK cytotoxicity up to 66.80% suggesting that lenalidomide can be used in parallel with such therapeutic vaccines as cancer vaccine or virus vaccines.

A comparative approach between heterologous prime-boost vaccination strategy and DNA vaccinations for rabies.

BACKGROUND AND AIM: Rabies is a widespread neurological zoonotic disease causing significant mortality rates, especially in developing countries. Although a vaccine for rabies is available, its production and scheduling are costly in such countries. Advances in recombinant DNA technology have made it a good candidate for an affordable vaccine. Among the proteins of rabies virus, the Glycoprotein (RVG) has been the major target for new vaccine development which plays the principal role in providing complete protection against RV challenge. The aim of this study is to produce recombinant RVG which could be a DNA vaccine candidate and to evaluate the efficiency of this construct in a prime-boost vaccination regimen, compared to commercial vaccine. METHODS: Cloning to pcDNA3.1(+) and expression of rabies virus glycoprotein gene in BSR cell  line were performed followed by SDS-PAGE and Western blot analysis of the expressed glycoprotein. The resulting genetic construct was used as a DNA vaccine by injecting 80 µg of the plasmid to MNRI mice twice. Prime-Boost vaccination strategy was performed using 80 µg plasmid construct as prime dose and the second dose of an inactivated rabies virus vaccine. Production of rabies virus neutralizing antibody (RVNA) titers of the serum samples were determined by RFFIT. RESULTS: In comparisons between heterologous prime-boost vaccination strategy and DNA vaccinations, the potency of group D that received Prime-Boost vaccine with the second dose of pcDNA3.1(+)-Gp was enhanced significantly compared to the group C which had received pcDNA3.1(+)-Gp as first injection. CONCLUSION: In this study, RVGP expressing construct was used in a comparative approach between Prime-Boost vaccination strategy and DNA vaccination and compared with the standard method of rabies vaccination. It was concluded that this strategy could lead to induction of acceptable humoral immunity.