• BMB Reports
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• v.40 no.6
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• pp.1002-1008
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• 2007

PreS domain of Hepatitis B virus (HBV) surface antigen is a good candidate for an effective vaccine as it activates both B and T cells besides binding to hepatocytes. This report deals with overexpression and purification of adr subtype of surface antigen that is more prevalent in Pakistan. PreS region, comprising 119 aa preS1 region plus a 55 aa preS2 region plus 11 aa from the N-terminal S region, was inserted in pET21a+ vector, cloned in E. coli $DH5\alpha$ cells and expressed in E. coli BL21 codon+ cells. The conditions for over expression were optimized using different concentrations of IPTG (0.01-5 mM), and incubating the cells at different temperatures (23-$41^{\circ}C$) for different durations (0-6 h). The cells were grown under the given optimized conditions (0.5 mM IPTG concentration at $37^{\circ}C$ for 4 h), lysed by sonication and the protein was purified by ion exchange chromatography. On the average, 24.5 mg of recombinant protein was purified per liter of culture. The purified protein was later lyophilized and stored at $-80^{\circ}C$.

• BMB Reports
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• v.47 no.4
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• pp.184-191
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• 2014

Respiratory syncytial virus (RSV) is the leading cause of respiratory infection in infants and young children. Severe clinical manifestation of RSV infection is a bronchiolitis, which is common in infants under six months of age. Recently, RSV has been recognized as an important cause of respiratory infection in older populations with cardiovascular morbidity or immunocompromised patients. However, neither a vaccine nor an effective antiviral therapy is currently available. Moreover, the interaction between the host immune system and the RSV pathogen during an infection is not well understood. The innate immune system recognizes RSV through multiple mechanisms. The first innate immune RSV detectors are the pattern recognition receptors (PRRs), including toll-like receptors (TLRs), retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs), and nucleotide-biding oligomerization domain (NOD)-like receptors (NLRs). The following is a review of studies associated with various PRRs that are responsible for RSV virion recognition and subsequent induction of the antiviral immune response during RSV infection.

• Molecules and Cells
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• v.22 no.2
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• pp.175-181
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• 2006

Delivery of DNA vaccines to airway mucosa would be an ideal method for mucosal immunization. However, there have been few reports of a suitable gene delivery system. In this study we used a cationic emulsion to immunize mice via the intranasal route with pCMV-S coding for Hepatitis B virus surface antigen (HBsAg). Complexing pCMV-S with a cationic emulsion dramatically enhanced HBsAg expression in both nasal tissue and lung, and was associated with increases in the levels of HBs-specific Abs in serum and mucosal fluids, of cytotoxic T lymphocytes (CTL) in the spleen and cervical and iliac lymph nodes, and of delayed-type hypersensitivity (DTH) against HBsAg. In contrast, very weak humoral and cellular immunities were observed following immunization with naked DNA. In support of these observations, a higher proliferative response of spleenocytes was detected in the group immunized with the emulsion/pCMV-S complex than in the group immunized with naked pCMV-S. These findings may facilitate development of an emulsion-mediated gene vaccination technique for use against intracellular pathogens that invade mucosal surfaces.

• Biomolecules & Therapeutics
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• v.20 no.3
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• pp.320-325
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• 2012

Rotavirus and hepatitis A virus (HAV) spread by the fecal-oral route and infections are important in public health, especially in developing countries. Here, two antigenic epitopes of the HAV polyprotein, domain 2 (D2) and domain 3 (D3), were recombined with rotavirus VP7, generating D2/VP7 and D3/VP7, cloned in a baculovirus expression system, and expressed in Spodoptera frugiperda 9 (Sf9) insect cells. All were highly expressed, with peak expression 2 days post-infection. Western blotting and ELISA revealed that two chimeric proteins were antigenic, but only D2/VP7 was immunogenic and elicited neutralizing antibody responses against rotavirus and HAV by neutralization assay, implicating D2/VP7 as a multivalent subunit-vaccine Candidate for preventing both rotavirus and HAV infections.

• IMMUNE NETWORK
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• v.20 no.1
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• pp.2.1-2.19
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• 2020

Acute viral infection or vaccination generates highly functional memory CD8 T cells following the Ag resolution. In contrast, persistent antigenic stimulation in chronic viral infection and cancer leads to a state of T-cell dysfunction termed T-cell exhaustion. We and other have recently identified a novel subset of exhausted CD8 T cells that act as stem cells for maintaining virus-specific CD8 T cells in a mouse model of chronic lymphocytic choriomeningitis virus infection. This stem cell-like CD8 T-cell subset has been also observed in both mouse and human tumor models. Most importantly, in both chronic viral infection and tumor models, the proliferative burst of Ag-specific CD8 T cells driven by PD-1-directed immunotherapy comes exclusively from this stem cell-like CD8 T-cell subset. Therefore, a better understanding of the mechanisms how CD8 T-cell subsets are regulated during chronic viral infection and cancer is required to improve the current immunotherapies that restore the function of exhausted CD8 T cells. In this review, we discuss the differentiation of virus-specific CD8 T cells during chronic viral infection, the characteristics and function of CD8 T-cell subsets, and the therapeutic intervention of PD-1-directed immunotherapy in cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8473-8477
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• 2016

Background: High risk human papilloma virus (HPV) types 16 and 18 have been proven as central causes of cervical cancer and safety and immunogenicity of HPV vaccines are sufficiently established. Knowledge and practices of HPV vaccination among medical and paramedical students is vital as these may strongly determine intention to recommend vaccination to others in the future. The present study was therefore undertaken to assess the knowledge, attitude and practices regarding cervical cancer screening and HPV vaccination among medical and paramedical students and to analyze factors influencing them. Materials and Methods: The present cross sectional study, conducted in a tertiary care teaching hospital in south India, included undergraduate students aged 18 years and above, belonging to medical, dental and nursing streams, after informed written consent. Results: Out of 957 participants, only 430 (44.9%) displayed good knowledge and only 65 (6.8%) had received HPV vaccination. Among the unvaccinated, 433 (48.54%), were not willing to take the vaccine. Concerns regarding the efficacy (30.5%), safety (26.1%) and cost of the vaccine (21.7%) were responsible for this. Age, gender, family history of malignancy and mother's education had no influence on knowledge. Compared to medical students, nursing students had better knowledge (OR-1.49, 95% CI 0.96 to 2.3, p = 0.072) and students of dentistry had poor knowledge (OR-0.50 95% CI 0.36 to 0.70, p<0.001). Conclusions: The knowledge and uptake of HPV vaccination among medical and paramedical students in India is poor. Targeted health education interventions may have huge positive impact not only on the acceptance of vaccination among them, but also on their intention to recommend the vaccine in future.

• Korean Journal of Veterinary Service
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• v.40 no.3
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• pp.177-185
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• 2017

In this study, we evaluated the efficacy of a commercial vaccine stress-relieving agent (Anti VS-2 injection) to reduce the adverse effects of foot-and-mouth disease (FMD) vaccination site in 120 pigs on two tested pig farms. The results showed that incidence of pig with abnormal meat, size of abnormal meat and weight of discarded abnormal meat are significantly decreased in Anti VS-2 injection-supplemented FMD vaccinated pig groups (n=60) compared to the non-supplemented FMD vaccinated pig groups (n=60) (P<0.05). And the average economic loss by discard of abnormal meat were estimated 99,382 won or 21,514 won in the non-supplemented FMD vaccinated groups or in the Anti VS-2 injection-supplemented FMD vaccinated groups, respectively, showing that the cost saving effect was 78% (77,869 won). In conclusion, it is expected to reduce the incidence and severity of abnormal meat in the FMD vaccinated pigs and to contribute not only to the reduced economic loss of pig farmers but also to the promotion of food hygiene when the Anti VS-2 injection is mixed with FMD vaccine.

• Korean Journal of Veterinary Service
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• v.34 no.2
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• pp.95-102
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• 2011

Foot-and-mouth disease (FMD) is one of the most infectious diseases affecting cloven-hoofed animals including cattle, sheep, goats, and pigs. Seven serotypes of foot-and-mouth disease virus with multiple subtypes within each serotype have been identified until now. In particular, it has been demonstrated that the outbreak of the serotype Asia1 reported from China, Mongolia and North Korea since 2005 is mostly classified into genetic group V. Though it has been recommended that Asia1 Shamir strain can be used as a high priority vaccine by World References Laboratory for FMD, the complete nucleotide sequences of the strain has not yet been determined. In this study, to be prepared for Asia1 type viruses that may be brought into Korea, the complete genome sequence of this vaccine strain Asia1 Shamir including its 5' and 3' non-coding region was identified.

• Kidney Research and Clinical Practice
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• v.37 no.4
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• pp.366-372
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• 2018

Background: An inactivated Hantaan virus vaccine (iHV) has been broadly used as a preventive strategy for hemorrhagic fever with renal syndrome (HFRS) by the South Korean Army. After the vaccination program was initiated, the overall incidence of HFRS cases was reduced in the military population. While there are about 400 HFRS cases annually, few studies have demonstrated the efficacy of the iHV in field settings. Therefore, this study aimed to evaluate the iHV efficacy on HFRS severity. Methods: From 2009 to 2017, HFRS cases were collected in South Korean Army hospitals along with patients' vaccination history. HFRS patients were classified retrospectively into two groups according to vaccination records: no history of iHV vaccination and valid vaccination. Vaccine efficacy on the severity of acute kidney injury (AKI) stage and dialysis events were investigated. Results: The effects of the iHV on renal injury severity in between 18 valid vaccinated and 110 non-vaccinated patients were respectively evaluated. In the valid vaccination group, six of the 18 HFRS patients (33.3%) had stage 3 AKI, compared to 60 of the 110 (54.5%) patients in the non-vaccination group. The iHV efficacy against disease progression ($VE_p$) was 58.1% (95% confidence interval, 31.3% to 88.0%). Conclusion: The iHV efficacy against the progression of HFRS failed to demonstrate statistically significant protection. However, different severity profiles were observed between the iHV and non-vaccination groups. Additional studies with larger populations are needed to demonstrate the effectiveness of the iHV in patients with HFRS.

• Journal of Microbiology and Biotechnology
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• v.29 no.5
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• pp.813-819
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• 2019

Middle East respiratory syndrome coronavirus (MERS-CoV) induces severe respiratory impairment with a reported mortality rate of ~36% in humans. The absence of clinically available MERS-CoV vaccines and treatments to date has resulted in uncontrolled incidence and propagation of the virus. In vaccine design, fusion with the IgG Fc domain is reported to increase the immunogenicity of various vaccine antigens. However, limited reports have documented the potential negative effects of Fc fusion on vaccine antigens. To determine whether Fc fusion affects the immunogenicity of MERS-CoV antigen, we constructed a Fcassociated MERS-CoV spike protein (eS770-Fc, 110 kDa), whereby human IgG4 Fc domain was fused to MERS-CoV spike protein (eS770) via a Gly/Pro linker using baculovirus as the expression system. For comparative analyses, two eS770 proteins lacking the IgG4 Fc domain were generated using the IdeS protease ($eS770-{\Delta}Fc$) or His tag attachment (eS770-His) and the immunogenicity of the above constructs were examined following intramuscular immunization in mice. Contrary to expectations, non-Fc spike proteins ($eS770-{\Delta}Fc$, eS770-His; 90 kDa) showed higher immunogenicity than the Fc fusion protein (eS770-Fc). Moreover, unlike non-Fc spike proteins, eS770-Fc immunization did not elicit neutralizing antibodies against MERS-CoV. The lower immunogenicity of Fc-fused eS770 was related to alterations in the structural conformation of the spike protein. Taken together, our results indicate that IgG Fc fusion reduces the immunogenicity of eS770 by interfering with the proper folding structure.