15 research outputs found
Exploring the usage of inactivated whole virus particle vaccines for influenza and COVID-19 [an abstract of dissertation and a summary of dissertation review]
No full text(主査) 教授 澤 洋文, 教授 迫田 義博, 准教授 新開 大史, 助教 大野 円実国際感染症学院（感染症学専攻
Inactivated Whole Virus Particle Influenza Vaccine Induces Anti-Neuraminidase Antibodies That May Contribute to Cross-Protection against Heterologous Virus Infection
No full textDespite the use of vaccines, seasonal influenza remains a risk to public health. We previously proposed the inactivated whole virus particle vaccine (WPV) as an alternative to the widely used split vaccine (SV) for the control of seasonal and pandemic influenza based on the superior priming potency of WPV to that of SV. In this study, we further examined and compared the immunological potency of monovalent WPV and SV of A/California/7/2009 (X-179A) (H1N1) pdm09 (CA/09) to generate immune responses against heterologous viruses, A/Singapore/GP1908/2015 (IVR-180) (H1N1) pdm09 (SG/15), and A/duck/Hokkaido/Vac-3/2007 (H5N1) (DH/07) in mice. Following challenge with a lethal dose of heterologous SG/15, lower virus titer in the lungs and milder weight loss were observed in WPV-vaccinated mice than in SV-vaccinated ones. To investigate the factors responsible for the differences in the protective effect against SG/15, the sera of vaccinated mice were analyzed by hemagglutination-inhibition (HI) and neuraminidase-inhibition (NI) assays to evaluate the antibodies induced against viral hemagglutinin (HA) and neuraminidase (NA), respectively. While the two vaccines induced similar levels of HI antibodies against SG/15 after the second vaccination, only WPV-vaccinated mice induced significantly higher titers of NI antibodies against the strain. Furthermore, given the significant elevation of NI antibody titers against DH/07, an H5N1 avian influenza virus, WPV was also demonstrated to induce NA-inhibiting antibodies that recognize NA of divergent strains. This could be explained by the higher conservation of epitopes of NA among strains than for HA. Taking these findings together, NA-specific antibodies induced by WPV may have contributed to better protection from infection with heterologous influenza virus SG/15, compared with SV. The present results indicate that WPV is an effective vaccine for inducing antibodies against both HA and NA of heterologous viruses and may be a useful vaccine to conquer vaccine strain mismatch
The problems of cross-border migration in the context of SADC regional integration
No full textPeople migrate to escape poverty and conflict, to seek protection from the persecution or serious harm, or to build a better life. Migration in Sothern Africa is frequently driven by the need to improve social and economic opportunities or to flee conditions of political insecurity. Based on the migration dynamics in the southern African Development community (SADC) region, this article focuses on the impact of cross-border migration in SADC region. The author explores some of the key issues in the migration discourse in the region, that is the main push factors influencing cross-border migration in the SADC region, as well the challenges linked to border migration. The article established that cross-border migration is a current and historical reality that impacts directly on most, if not all SADC member states- some essentially as sending countries, others essentially as receiving countries. The author concludes that cross border migration in southern Africa has played a vital role in SADC regional integration and has contributed to the economic development of SADC member states. However, the absence of a regionally accepted policy aimed at regulating migration means that illegal or undocumented cross-border migration will continue being a problem in the region.Люди мигрируют, чтобы избежать нищеты и конфликтов, в поисках защиты от преследований или серьезного вреда или в поисках лучшей жизни. Миграция в Южной Африке часто вызвана необходимостью улучшения социальных и экономических возможностей или бегством от условий политической нестабильности. Основываясь на динамике миграции в регионе Сообщества развития юга Африки (САДК), в этой статье основное внимание уделяется влиянию трансграничной миграции в регионе САДК. Автор исследует некоторые из ключевых вопросов миграционного дискурса в регионе, то есть основные факторы, влияющие на трансграничную миграцию в регионе САДК, а также проблемы, связанные с приграничной миграцией. В статье установлено, что трансграничная миграция представляет собой текущую и историческую реальность, которая оказывает непосредственное влияние на большинство, если не на все государства-члены САДК: некоторые в основном как отправляющие страны, другие в основном как принимающие страны. Автор приходит к выводу, что трансграничная миграция на юге Африки сыграла жизненно важную роль в региональной интеграции САДК и способствовала экономическому развитию государств-членов САДК. Однако отсутствие принятой на региональном уровне политики, направленной на регулирование миграции, означает, что незаконная или незарегистрированная трансграничная миграция будет оставаться проблемой в регионе
Inactivated Whole Virus Particle Influenza Vaccine Induces Anti-Neuraminidase Antibodies That May Contribute to Cross-Protection against Heterologous Virus Infection
No full textRegional Security Integration in the SADC Region
No full textThe Southern African Development Community (SADC) is one of Africa’s most vivid examples of security integration. As the regional group aspires to promote political and economic independence, peace and security are considered indispensable for regional development, as instability in one member state could harm neighboring countries. Methods and materials. Relevant literature was critically analyzed, and the study adopted a secondary data collection method as an approach. Using the theory of security communities and theories of integration, this paper analyzed the historical security cooperation between the countries in the region as the first step towards regional integration in Southern Africa, that is, the restraining of the apartheid regime in South Africa. Analysis. The analysis further focused on establishing and evolving the Organ on Politics, Defense, and Security (OPDS) and its institutional relationship with the SADC Summit. Results. The findings showed that SADC faced more internal challenges than external ones, which led to regional integration. Leading factors in the lack of peace and security were armed conflict, legacy of violence, and poor governance, among others. SADC envisioned peace and security through the adopted Strategic Indicative Plan for the Organ (SIPO). The author concludes that the SADC Summit and the OPDS are the leading platforms for managing security issues in the SADC region
Selecting and using the appropriate influenza vaccine for each individual
No full textDespite seasonal influenza vaccines having been routinely used for many decades, influenza A virus continues to pose a global threat to humans, causing high morbidity and mortality each year. The effectiveness of the vaccine is largely dependent on how well matched the vaccine strains are with the circulating influenza virus strains. Furthermore, low vaccine efficacy in naïve populations such as young children, or in the elderly, who possess weakened immune systems, indicates that influenza vaccines need to be more personalized to provide broader community protection. Advances in both vaccine technologies and our understanding of influenza virus infection and immunity have led to the design of a variety of alternate vaccine strategies to extend population protection against influenza, some of which are now in use. In this review, we summarize the progress in the field of influenza vaccines, including the advantages and disadvantages of different strategies, and discuss future prospects. We also highlight some of the challenges to be faced in the ongoing effort to control influenza through vaccination
Potent priming by inactivated whole influenza virus particle vaccines is linked to viral RNA uptake into antigen presenting cells
No full textCurrent detergent or ether-disrupted split vaccines (SVs) for influenza do not always induce adequate immune responses, especially in young children. This contrasts with the whole virus particle vaccines (WPVs) originally used against influenza that were immunogenic in both adults and children but were replaced by SV in the 1970s due to concerns with reactogenicity. In this study, we re-evaluated the immunogenicity of WPV and SV, prepared from the same batch of purified influenza virus, in cynomolgus macaques and confirmed that WPV is superior to SV in priming potency. In addition, we compared the ability of WPV and SV to induce innate immune responses, including the maturation of dendritic cells (DCs) in vitro. WPV stimulated greater production of inflammatory cytokines and type-I interferon in immune cells from mice and macaques compared to SV. Since these innate responses are likely triggered by the activation of pattern recognition receptors (PRRs) by viral RNA, the quantity and quality of viral RNA in each vaccine were assessed. Although the quantity of viral RNA was similar in the two vaccines, the amount of viral RNA of a length that can be recognized by PRRs was over 100-fold greater in WPV than in SV. More importantly, 1000-fold more viral RNA was delivered to DCs by WPV than by SV when exposed to preparations containing the same amount of HA protein. Furthermore, WPV induced up regulation of the DC maturation marker CD86 on murine DCs, while SV did not. The present results suggest that the activation of antigen-presenting DCs, by PRR-recognizable viral RNA contained in WPV is responsible for the effective priming potency of WPV observed in naive mice and macaques. WPV is thus recommended as an alternative option for seasonal influenza vaccines, especially for children. (c) 2021 Elsevier Ltd. All rights reserved
