• 한국미생물학회:학술대회논문집
• /
• 한국미생물학회 2000년도 추계학술발표대회
• /
• pp.78-82
• /
• 2000

The AIDS epidemic continues unabated in many part of the world. After near two decades, no vaccine is available to combat the spread of this deadly disease. Much of the HIV -1 vaccine effort during the past decade has focused on the viral envelope glycoprotein, largely because it is the only protein that can elicit neutralizing antibodies (Nabs). Eliciting broadly cross-reactive Nabs has been a primary goal. The intrinsic genetic diversity of the viral envelope, however, has been one of the major impediments in vaccine development. We have recently completed a comprehensive study examining whether it is possible to elicit broadly acting Nabs by immunizing monkeys with mixtures of envelope proteins from multiple HIV -1 isolates. We compared the humoral immune responses elicited by vaccination with either single or multiple envelope proteins and evaluated the importance of humoral and non-humoral immune response in protection against a challenge virus with a homologous or heterologous envelope protein. Our results show that (1) Nab is the correlate of sterilizing immunity, (2) Nabs against primary HIV -1 isolates can be elicited by the live vector-prime/protein boost approach, and (3) polyvalent envelope vaccines elicit broader Nab response than monovalent vaccines. Nonetheless, our findings clearly indicate that the increased breadth of Nab response is by and large limited to strains included in the vaccine mixture and does not extend to heterologous non-vaccine strains. Our study strongly demonstrates how difficult it may be to elicit broadly reactive Nabs using envelope proteins and sadly predicts a similar fate for many of the vaccine candidates currently being evaluated in clinical trials. We have started to evaluate other vaccine candidates (e.g. genetically modified envelope proteins) that might elicit broadly reactive Nabs. We are also exploring other vaccine strategies to elicit potent cytotoxic T lymphocyte responses. Preliminary results from some of these experiments will be discussed.

• 한국군사과학기술학회지
• /
• 제27권1호
• /
• pp.107-115
• /
• 2024

Various vaccines were rapidly developed during the COVID-19 pandemic to prevent and treat infections but global infections continue, and concerns about new mutations and infectious diseases persist. Thus, active research focuses on developing, producing, and supplying vaccines and treatments for various infectious diseases and potential pandemics. Natural killer(NK) cells, as innate immune cells, can recognize and eliminate abnormal cells like virus-infected and cancer cells. Hence, their development as anticancer and antiviral treatments is rapidly advancing. In this study, optimal short-term culture conditions were identified for allogeneic NK cells by simplifying the culture process through the isolation of NK cells(referred to as NKi cells) and eliminating CD3+ cells(referred to as CD3- cells). NK cells demonstrated reduced viral titer in injection of NK cells into SARS-CoV-2 infected ACE-tg mice increased survival. The study's findings could form the basis for an antiviral treatment platform that swiftly responds to new viral disease pandemics.

• Pediatric Infection and Vaccine
• /
• 제7권1호
• /
• pp.83-93
• /
• 2000

목 적 : Urabe AM-9 볼거리 백신주는 무균성 뇌막염의 발생 빈도가 높은 것으로 알려져 있다. 백신 접종 후 무균성 뇌막염을 일으키는 경우 Urabe AM-9 백신주의 hemagglutinin-neuraminidase(HN) 유전자의 염기서열 1081번의 G가 A로 치환되어 335번째 아미노산이 glutamic acid에서 lysine으로 바뀌게 됨에 따라 야생형의 mumps 바이러스와 동일한 작용을 나타내는 것으로 알려져 있다. 이에 국내에서 사용중인 Urabe AM-9 백신주의 안전성 여부를 조사하기 위해 일부 백신주와 야생 분리주의 HN 유전자의 염기서열 분석을 실시하였다. 방 법 : 국내에서 사용되고있는 Urabe AM-9주 백신 2종류와 1998~1999년에 볼거리 환자로부터 분리된 야생 분리주를 이용하여 RT-PCR 방법에 의해 HN 유전자를 증폭시킨 후 염기 및 아미노산 서열 분석을 실시하였다. 결 과 : 백신주와 야생 분리주 모두 HN 343, 1476, 1570번 위치에서의 염기 변이는 없었으나 1081번 위치 염기는 모두 야생주와 같은 Lysine/AAA form으로 나타났으며 변이주인 Glutamic acid/GAA와의 혼합 양상은 관찰되지 않았다. HN 1470번 위치의 염기는 백신주 중 계대 배양시 C에서 A로 치환되었으며, HN 1727번 위치 염기는 모두 A에서 G로 치환된 것으로 나타났다. 결 론 : 국내에서 사용중인 2종류의 Urabe AM-9 백신주와 야생 분리주 모두 1081번 위치의 염기가 야생주와 같은 무균성 뇌막염을 일으킬 생물학적 가능성이 있는 것으로 나타났으며, 국내에서도 상기 백신주를 사용한 후 무균성 뇌막염이 발생하고 있을 개연성이 매우 크다고 사료되며 직접적인 연관성에 대한 보완 연구를 위하여 정확하고 믿을만한 자료에 의한 실제 부작용 실태를 파악하여야 한다.

• Journal of Plant Biotechnology
• /
• 제41권1호
• /
• pp.50-55
• /
• 2014

Plant-based vaccines possess some advantages over other types of vaccine biotechnology such as safety, low cost of mass vaccination programs, and wider use of vaccines for medicine. This study was undertaken to develop the transgenic maize as edible vaccine candidates for humans. The immature embryos of HiII genotype were inoculated with A. tumefaciens strain C58C1 containing the binary vectors (V662 or V663). The vectors carrying nptII gene as selection marker and scEDIII (V662) or wCTB-scEDIII (V663) target gene, which code EIII proteins inhibite viral adsorption by cells. In total, 721 maize immature embryos were transformed and twenty-two putative transgenic plants were regenerated after 12 weeks selection regime. Of them, two- and six-plants were proved to be integrated with scEDIII and wCTB-scEDIII genes, respectively, by Southern blot analysis. However, only one plant (V662-29-3864) can express the gene of interest confirmed by Northern blot analysis. These results demonstrated that this plant could be used as a candidated source of the vaccine production.

• 대한두경부종양학회지
• /
• 제38권1호
• /
• pp.11-16
• /
• 2022

HHPV (Human Papillomavirus) is a DNA virus that can cause benign lesions, genitourinary cancer, and oropharyngeal cancer by penetrating the mucous membrane and skin. It is widely known to be transmitted mainly through sexual contact. As with many viral infections, vaccines have been developed to prevent infection with HPV. Currently, in many countries, HPV vaccines are mainly used for national immunization for women to prevent diseases that traditionally occur frequently in women, especially cervical cancer. However, since the vaccination rate is relatively low, many countries are struggling with ways to increase the vaccination rate. Meanwhile, the incidence of oropharyngeal cancer caused by HPV in men has been increasing recently. In the United States, the annual number of oropharyngeal cancers in men already exceeds the number of cervical cancers in women, so HPV infection in men has emerged as a major problem. Accordingly, interest in HPV vaccination in men has also increased, and studies on the effectiveness and necessity of vaccination of both women and men compared to women alone are being actively conducted. In this paper, the evidence of HPV vaccination for men will be reviewed through previous studies, and its validity and cost-effectiveness will be analyzed to bolster the clinical usefulness of HPV vaccination for men.

• Journal of Ginseng Research
• /
• 제47권6호
• /
• pp.687-693
• /
• 2023

Due to the Covid-19 pandemic more than 6 million people have died, and it has bought unprecedented challenges to our lives. The recent outbreak of monkeypox virus (MPXV) has brought out new tensions among the scientific community. Currently, there is no specific treatment protocol for MPXV. Several antivirals, vaccinia immune globulin (VIG) and smallpox vaccines have been used to treat MPXV. Ginseng, one of the more famous among traditional medicines, has been used for infectious disease for thousands of years. It has shown promising antiviral effects. Ginseng could be used as a potential adaptogenic agent to help prevent infection by MPXV along with other drugs and vaccines. In this mini review, we explore the possible use of ginseng in MPXV prevention based on its antiviral activity.

• Journal of Microbiology and Biotechnology
• /
• 제25권10호
• /
• pp.1761-1767
• /
• 2015

Sevenband grouper, Epinephelus septemfasciatus, is becoming an important aquaculture species in Korea. However, viral nervous necrosis disease is a large problem causing mass mortality in sevenband grouper aquaculture. Recombinant protein vaccines are one of the best methods to reduce these economic losses. However, the cell-based expression method mainly produces inclusion bodies and requires additional procedures. In this study, we expressed a recombinant viral coat protein of sevenband grouper nervous necrosis virus (NNV) using a cell-free protein synthesis system. The purified recombinant NNV coat protein (rNNV-CP) was injected into sevenband grouper at different doses followed by a NNV challenge. Nonimmunized fish in the first trial (20 μg/fish) began to die 5 days post-challenge and reached 70% cumulative mortality. In contrast, immunized fish also starting dying 5 days postchallenge but lower cumulative mortality (10%) was observed. Cumulative morality in the second trial with different doses (20, 4, and 0.8 μg/fish) was 10%, 40%, and 50%, respectively. These results suggest that rNNV-CP can effectively immunize sevenband grouper depending on the dose administered. This study provides a new approach to develop a recombinant vaccine against NNV infection for sevenband grouper.

• Molecules and Cells
• /
• 제44권9호
• /
• pp.688-695
• /
• 2021

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has become a global health concern. Various SARS-CoV-2 vaccines have been developed and are being used for vaccination worldwide. However, no therapeutic agents against coronavirus disease 2019 (COVID-19) have been developed so far; therefore, new therapeutic agents are urgently needed. In the present study, we evaluated several hepatitis C virus direct-acting antivirals as potential candidates for drug repurposing against COVID-19. Theses include asunaprevir (a protease inhibitor), daclatasvir (an NS5A inhibitor), and sofosbuvir (an RNA polymerase inhibitor). We found that asunaprevir, but not sofosbuvir and daclatasvir, markedly inhibited SARS-CoV-2-induced cytopathic effects in Vero E6 cells. Both RNA and protein levels of SARS-CoV-2 were significantly decreased by treatment with asunaprevir. Moreover, asunaprevir profoundly decreased virion release from SARS-CoV-2-infected cells. A pseudoparticle entry assay revealed that asunaprevir blocked SARS-CoV-2 infection at the binding step of the viral life cycle. Furthermore, asunaprevir inhibited SARS-CoV-2 propagation in human lung Calu-3 cells. Collectively, we found that asunaprevir displays broad-spectrum antiviral activity and therefore might be worth developing as a new drug repurposing candidate for COVID-19.

• Journal of Microbiology and Biotechnology
• /
• 제29권1호
• /
• pp.127-140
• /
• 2019

Since 1990, many nucleic acid expression platforms consisting of DNA or RNA have been developed. However, although RNA expression platforms have been relatively neglected, several such platforms capped at the 5' end of RNA by an anti-reverse cap analog have now been developed. At the same time, the capping reaction is a bottleneck in the production of such platforms, with high cost and low efficiency. Here, we investigated several viral and eukaryotic internal ribosome entry sites (IRESs) to develop an optimal RNA expression platform, because IRES-dependent translation does not require a capping step. RNA expression platforms constructed with IRESs from the 5' untranslated regions of the encephalomyocarditis virus (EMCV) and the intergenic region of the cricket paralysis virus (CrPV) showed sufficient expression efficiency compared with cap-dependent RNA expression platforms. However, eukaryotic IRESs exhibited a lower viral IRES expression efficiency. Interestingly, the addition of a poly(A) sequence to the 5' end of the coxsackievirus B3 (CVB3) IRES (pMA-CVB3) increased the expression level compared with the CVB3 IRES without poly(A) (pCVB3). Therefore, we developed two multiexpression platforms (termed pMA-CVB3-EMCV and pCrPV-EMCV) by combining the IRESs of CVB3, CrPV, and EMCV in a single-RNA backbone. The pMA-CVB3-EMCV-derived RNA platform showed the highest expression level. Moreover, it clearly exhibited expression in mouse muscles in vivo. These RNA expression platforms prepared using viral IRESs will be useful in developing potential RNA-based prophylactic or therapeutic vaccines, because they have better expression efficiency and do not need a capping step.

• Journal of Microbiology and Biotechnology
• /
• 제33권12호
• /
• pp.1587-1594
• /
• 2023

Since its first report in 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed a grave threat to public health. Virus-specific countermeasures, such as vaccines and therapeutics, have been developed and have contributed to the control of the viral pandemic, which has become endemic. Nonetheless, new variants continue to emerge and could cause a new pandemic. Consequently, it is important to comprehensively understand viral evolution and the roles of mutations in viral infectivity and transmission. SARS-CoV-2 beta variant encode mutations (D614G, N501Y, E484K, and K417N) in the spike which are frequently found in other variants as well. While their individual role in viral infectivity has been elucidated against various therapeutic antibodies, it still remains unclear whether those mutations may act additively or synergistically when combined. Here, we report that N501Y mutation shows differential effect on two therapeutic antibodies tested. Interestingly, the relative importance of E484K and K417N mutations in antibody evasion varies depending on the antibody type. Collectively, these findings suggest that continuous efforts to develop effective antibody therapeutics and combinatorial treatment with multiple antibodies are more rational and effective forms of treatment.