neutralization and antibody dependent enhancement of dengue viruses pdf Saturday, December 19, 2020 7:53:15 AM

Neutralization And Antibody Dependent Enhancement Of Dengue Viruses Pdf

File Name: neutralization and antibody dependent enhancement of dengue viruses .zip
Size: 2405Kb
Published: 19.12.2020

If the address matches an existing account you will receive an email with instructions to reset your password. If the address matches an existing account you will receive an email with instructions to retrieve your username. In general, virus-specific antibodies are considered antiviral and play an important role in the control of virus infections in a number of ways.

Dengue virus DENV is the cause of dengue fever.

The challenges associated with whole DENV-based vaccine strategies necessitate re-focusing our attention toward the designed dengue vaccine candidates, capable of inducing predominantly type-specific immune responses. The generation of type-specific antibodies to each of the four DENV serotypes by the designed vaccines could avoid the immune evasion mechanisms of DENVs. For the enhanced vaccine safety, all dengue vaccine candidates should be assessed for the extent of type-specific minimal ADE vs. The type-specific EDIII antibodies may be more directly related to protection from disease in the absence of ADE promoted by the cross-reactive antibodies. The world needs a dengue vaccine for all age groups, regardless of whether they may, or may not have been previously exposed to one of the four dengue viruses.

The Complexity of Antibody-Dependent Enhancement of Dengue Virus Infection

Infection with each DENV serotype causes an array of clinical diseases, ranging from dengue without warning signs, dengue with warning signs to severe dengue-dengue haemorrhagic fever and dengue shock syndrome 1 — 4. Individuals infected with one serotype can acquire lifelong homotypic immunity 5 ; however, those suffering secondary DENV infection with another serotype may have a greater risk of progressing to severe dengue 6. The presence of ADE impedes the development of dengue vaccines to induce protective neutralizing antibodies without enhancing viral replication. The surface of the mature DENV particle is covered with 90 head-to-tail homodimers of envelope glycoprotein E 8 , which is the major surface protein of flaviviruses involved in multiple processes, such as viral adsorption, membrane fusion and cell tropism. EDIII-reactive antibodies are found in convalescent sera from patients infected with dengue 10 ,

The pathogenesis of dengue virus infection is attributed to complex interplay between virus, host genes and host immune response. Host factors such as antibody-dependent enhancement ADE , memory cross-reactive T cells, anti-DENV NS1 antibodies, autoimmunity as well as genetic factors are major determinants of disease susceptibility. Genomic variation of dengue virus and subgenomic flavivirus RNA sfRNA suppressing host immune response are viral determinants of disease severity. Apart from viral factors, several host genetic factors and gene polymorphisms also have a role to play in pathogenesis of DENV infection. This review article highlights the various factors responsible for the pathogenesis of dengue and also highlights the recent advances in the field related to biomarkers which can be used in future for predicting severe disease outcome. Dengue infection is a major public health problem and has been reported from the Americas, Africa, Southeast Asia, Europe, Western Pacific, and Eastern Mediterranean regions.

Antibody-Dependent Enhancement of Viral Infections

Antiviral antibodies constitute an important component of the host immune response against viral infections and serve to neutralize and reduce infectivity of the virus. However, these antibodies, intended to protect the host, may sometimes prove beneficial to the virus, by facilitating viral entry and replication in the target cell. The internalized immune complexes then modulate host immune response so as to enhance viral replication and aggravate disease severity. The possibility of induction of ADE remains a concern in the development and implementation of viral vaccines and immunotherapeutics. Antibody-dependent enhancement ADE of infection represents a paradoxical phenomenon in host—pathogen biology, in which, antibody, an important pillar of the host defense against invading pathogen, actually allows entry of the pathogen into host territory. This traitorous behavior of the antibody further serves to weaken the host defense system and thus generates an environment conducive for enhanced growth of the pathogen and consequently exacerbates disease in the host. This phenomenon has far-reaching implications for disease control and prevention, as therapeutic antibodies deployed to protect the host may aid the pathogen instead.

Antibody-Dependent Enhancement of Virus Infection and Disease

Protocol DOI: This chapter outlines methods for the production of dengue virus DENV reporter virus particles RVPs and their use in assays that measure antibody-mediated neutralization and enhancement of DENV infection. RVPs are pseudo-infectious virions. RVPs are pseudo-infectious virions produced by complementation of a self-replicating flavivirus replicon with the DENV structural genes in trans. RVPs harvested from transfected cells are capable of only a single round of infection and encapsidate replicon RNA that encodes a reporter gene used to enumerate infected cells.

Metrics details. Antibodies are critical responses to protect the host from dengue virus DENV infection. Antibodies target DENV by two pathologic mechanisms: virus neutralization and infection enhancement.

Antibody-dependent enhancement ADE has been proposed as a mechanism to explain dengue hemorrhagic fever DHF in the course of a secondary dengue infection.

Antibody-Dependent Enhancement: A Challenge for Developing a Safe Dengue Vaccine

Четыре на шестнадцать. - Шестьдесят четыре, - сказала она равнодушно.  - Ну и. Дэвид приблизился поближе к камере. Теперь его лицо занимало экран целиком. - Шестьдесят четыре знака… Сьюзан кивнула: - Да, но они… - Она вдруг замерла.

Она в страхе повернулась, думая, что это Хейл. Однако в дверях появился Стратмор. Бледная, жуткая в тусклом свете мониторов фигура застыла, грудь шефа тяжело вздымалась. - Ком… мандер! - вскрикнула она от неожиданности.

ЭНИГМА, это двенадцатитонное чудовище нацистов, была самой известной в истории шифровальной машиной. Там тоже были группы из четырех знаков. - Потрясающе, - страдальчески сказал директор.  - У вас, часом, нет такой же под рукой.

Тут он услышал знакомый металлический скрежет и, подняв глаза, увидел такси, спускавшееся вниз по пандусу в сотне метров впереди. Съехав на эту же улицу, оно начало набирать скорость, двигаясь прямо в лоб мотоциклу. Он должен был бы удариться в панику, но этого не произошло: он точно знал, куда держит путь. Свернув влево, на Менендес-пелайо, он прибавил газу.

ORG У человека, назвавшегося Северной Дакотой, анонимные учетные данные, но Сьюзан знала, что это ненадолго. Следопыт проникнет в ARA, отыщет Северную Дакоту и сообщит истинный адрес этого человека в Интернете. Если все сложится нормально, она скоро выяснит местонахождение Северной Дакоты, и Стратмор конфискует ключ.


Talbot G. 24.12.2020 at 06:52

Neutralization and Antibody-Dependent Enhancement of Dengue Viruses. February ; Advances Request Full-text Paper PDF. To read the full-text of this.

Ozibear 25.12.2020 at 06:47

Mayra R.