• Journal of Microbiology and Biotechnology
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• 제32권9호
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• pp.1073-1085
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• 2022

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has continued for over 2 years, following the outbreak of coronavirus-19 (COVID-19) in 2019. It has resulted in enormous casualties and severe economic crises. The rapid development of vaccines and therapeutics against SARS-CoV-2 has helped slow the spread. In the meantime, various mutations in the SARS-CoV-2 have emerged to evade current vaccines and therapeutics. A better understanding of SARS-CoV-2 pathogenesis is a prerequisite for developing efficient, advanced vaccines and therapeutics. Since the outbreak of COVID-19, a tremendous amount of research has been conducted to unveil SARS-CoV-2 pathogenesis, from clinical observations to biochemical analysis at the molecular level upon viral infection. In this review, we discuss the molecular mechanisms of SARS-CoV-2 propagation and pathogenesis, with an update on recent advances.

• 생명과학회지
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• 제33권9호
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• pp.746-753
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• 2023

바이러스성 전염병은 전 세계 공중 보건에 가장 큰 위협 중 하나로 간주된다. 최근 중증급성호흡기증후군 코로나바이러스-2(SARS-CoV-2)로 인한 COVID-19 대유행은 신종 바이러스 감염의 위협을 극명하게 상기시켜 주었다. 효율적인 백신과 치료제 개발 및 생산은 팬데믹을 퇴치할 수 있는 유일한 대안일 것이며 COVID-19 대유행은 새로운 바이러스성 질병을 통제하고 예방하기 위한 새로운 백신 플랫폼의 필요성을 보여주었다. 기존의 백신 플랫폼인 약독화 생백신, 불활성화 백신은 백신 개발 속도, 제조 등이 광범위한 백신 적용을 위한 긴급 사용에 한계가 있다. 흥미롭게도, COVID-19 예방을 위한 SARS-CoV-2 mRNA-지질나노입자(LNP) 플랫폼은 기존 백신 플랫폼 한계에 대한 효과적인 대안임이 확인되었다. 또한 COVID-19 mRNA 핵산 백신과 나노입자 기반 플랫폼은 SARS-CoV-2 및 변종 SARS-CoV-2 모두에 효과적인 백신임이 확인되었다. 이 논문에서는 mRNA 백신, 디지털 백신 및 나노입자백신 등의 차세대 백신 플랫폼을 중점으로 백신 기술 및 플랫폼의 장단점에 대해 기술하였다.

• IMMUNE NETWORK
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• 제21권1호
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• pp.2.1-2.11
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• 2021

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes coronavirus disease 2019 (COVID-19), an ongoing pandemic disease. In the current review, we describe SARS-CoV-2-specific CD4⁺ and CD8⁺ T-cell responses in acute and convalescent COVID-19 patients. We also discuss the relationships between COVID-19 severity and SARS-CoV-2-specific T-cell responses and summarize recent reports regarding SARS-CoV-2-reactive T cells in SARS-CoV-2-unexposed individuals. These T cells may be cross-reactive cells primed by previous infection with human common-cold coronaviruses. Finally, we outline SARS-CoV-2-specific T-cell responses in the context of vaccination. A better understanding of SARS-CoV-2-specific T-cell responses is needed to develop effective vaccines and therapeutics.

• Molecules and Cells
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• 제44권6호
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• pp.401-407
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• 2021

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), which is an ongoing pandemic disease. SARS-CoV-2-specific CD4⁺ and CD8⁺ T-cell responses have been detected and characterized not only in COVID-19 patients and convalescents, but also unexposed individuals. Here, we review the phenotypes and functions of SARS-CoV-2-specific T cells in COVID-19 patients and the relationships between SARS-CoV-2-specific T-cell responses and COVID-19 severity. In addition, we describe the phenotypes and functions of SARS-CoV-2-specific memory T cells after recovery from COVID-19 and discuss the presence of SARS-CoV-2-reactive T cells in unexposed individuals and SARS-CoV-2-specific T-cell responses elicited by COVID-19 vaccines. A better understanding of T-cell responses is important for effective control of the current COVID-19 pandemic.

• Molecules and Cells
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• 제44권6호
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• pp.392-400
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• 2021

It has been more than a year since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first emerged. Many studies have provided insights into the various aspects of the immune response in coronavirus disease 2019 (COVID-19). Especially for antibody treatment and vaccine development, humoral immunity to SARS-CoV-2 has been studied extensively, though there is still much that is unknown and controversial. Here, we introduce key discoveries on the humoral immune responses in COVID-19, including the immune dynamics of antibody responses and correlations with disease severity, neutralizing antibodies and their cross-reactivity, how long the antibody and memory B-cell responses last, aberrant autoreactive antibodies generated in COVID-19 patients, and the efficacy of currently available therapeutic antibodies and vaccines against circulating SARS-CoV-2 variants, and highlight gaps in the current knowledge.

• 대한의생명과학회지
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• 제28권2호
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• pp.67-82
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• 2022

The prevalence of SARS-CoV-2 led to inconsistent public health policies that resulted in COVID-19 containment failure. These factors resulted in increased hospitalization and death. To prevent viral spread and achieve herd immunity, the only safe and effective measure is to provide to vaccinates. Ever since the release of the SARS-CoV-2 nucleotide sequence in January of 2020, research centers and pharmaceutical companies from many countries have developed different types of vaccines including mRNA, recombinant protein, and viral vector vaccines. Prior to initiating vaccinations, phase 3 clinical trials are necessary. However, no vaccine has yet to complete a phase 3 clinical trial. Many products obtained "emergency use authorization" from governmental agencies such as WHO, FDA etc. The Korean government authorized the use of five different vaccines. The viral vector vaccine of Oxford/AstraZeneca and the Janssen showed effectiveness of 76% and 66.9%, respectively. The mRNA vaccine of Pfizer-BioNTech and Moderna showed effectiveness of 95% and 94.1%, respectively. The protein recombinant vaccine of Novavax showed an effectiveness of 90.4%. In this review, we compared the characteristics, production platform, synthesis principles, authorization, protective effects, immune responses, clinical trials and adverse effects of five different vaccines currently used in Korea. Through this review, we conceptualize the importance of selecting the optimal vaccine to prevent the COVID-19 pandemic.

• 한국미생물·생명공학회지
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• 제48권3호
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• pp.252-266
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• 2020

The coronavirus disease 2019 (COVID-19) is a highly contagious pneumonia that has spread throughout the world. It is caused by a novel, single stranded RNA virus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Genetic analysis revealed that, phylogenetically, the SARS-CoV-2 is related to severe acute respiratory syndrome-like viruses seen in bats. Because of this, bats are considered as a possible primary reservoir. The World Health Organization has declared the COVID-19 outbreak as a pandemic. As of May 27, 2020, more than 5,406,282 confirmed cases, and 343,562 confirmed deaths have been reported worldwide. Currently, there are no approved vaccines or antiviral drugs available against COVID-19. Newly developed vaccines are in the first stage of clinical trials, and it may take a few months to a few years for their commercialization. At present, remdesivir and chloroquine are the promising drugs for treating COVID-19 patients. In this review, we summarize the diversity, genetic variations, primary reservoirs, epidemiology, clinical manifestations, pathogenesis, diagnosis, treatment strategies, and future prospects with respect to controlling the spread of COVID-19.

• IMMUNE NETWORK
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• 제23권2호
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• pp.19.1-19.10
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• 2023

Endemic human coronaviruses (HCoVs) have been evidenced to be cross-reactive to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although a correlation exists between the immunological memory to HCoVs and coronavirus disease 2019 (COVID-19) severity, there is little experimental evidence for the effects of HCoV memory on the efficacy of COVID-19 vaccines. Here, we investigated the Ag-specific immune response to COVID-19 vaccines in the presence or absence of immunological memory against HCoV spike Ags in a mouse model. Pre-existing immunity against HCoV did not affect the COVID-19 vaccine-mediated humoral response with regard to Ag-specific total IgG and neutralizing Ab levels. The specific T cell response to the COVID-19 vaccine Ag was also unaltered, regardless of pre-exposure to HCoV spike Ags. Taken together, our data suggest that COVID-19 vaccines elicit comparable immunity regardless of immunological memory to spike of endemic HCoVs in a mouse model.

• IMMUNE NETWORK
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• 제21권1호
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• pp.5.1-5.22
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• 2021

Coronavirus disease 2019 (COVID-19) has developed as a pandemic, and it created an outrageous effect on the current healthcare and economic system throughout the globe. To date, there is no appropriate therapeutics or vaccines against the disease. The entire human race is eagerly waiting for the development of new therapeutics or vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Efforts are being taken to develop vaccines at a rapid rate for fighting against the ongoing pandemic situation. Amongst the various vaccines under consideration, some are either in the preclinical stage or in the clinical stages of development (phase-I, -II, and -III). Even, phase-III trials are being conducted for some repurposed vaccines like Bacillus Calmette-Guérin, polio vaccine, and measles-mumps-rubella. We have highlighted the ongoing clinical trial landscape of the COVID-19 as well as repurposed vaccines. An insight into the current status of the available antigenic epitopes for SARS-CoV-2 and different types of vaccine platforms of COVID-19 vaccines has been discussed. These vaccines are highlighted throughout the world by different news agencies. Moreover, ongoing clinical trials for repurposed vaccines for COVID-19 and critical factors associated with the development of COVID-19 vaccines have also been described.

• Clinical and Experimental Vaccine Research
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• 제12권3호
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• pp.224-231
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• 2023

Purpose: The Sinovac and AstraZeneca vaccines are the primary coronavirus disease 2019 vaccines in Indonesia. Antibody levels in vaccine-injected individuals will decline substantially over time, but data supporting the duration of such responses are limited. Therefore, this study aims to quantitatively evaluate antibody responses resulting from the completion of Sinovac and AstraZeneca administration in Indonesian adults. Materials and Methods: Participants were divided into two groups based on their vaccine type. Both groups were then assessed on the anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor binding domain (anti-SRBD) concentrations. The anti-SRBD level was measured using Elecsys anti-SARS-CoV-2 S assay and analyzed every month until 3 months after the second vaccination. Results: The results presented significant differences (p=0.000) in immunoglobulin G (IgG) titers among the vaccines' measurement duration, where all samples observed a decrease in IgG titers over time. The mean titer levels of anti-SRBD IgG in the group given Sinovac were high in the first month after vaccination and decreased by 55.7% in 3 months. AstraZeneca showed lesser immune response with a slower decline rate. Adverse effects following immunization (AEFI) showed that systemic reactions are the most reported in both vaccines, with a higher percentage in the second dose of AstraZeneca type vaccines. Conclusion: Sinovac induced more significant titers of anti-SRBD IgG 1 month after the second dose but generated fewer AEFIs. In contrast, AstraZeneca generated more AEFIs, in mild to moderate severity, but provided lower levels of anti-SRBD IgG.