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Order Amarillovirales
Published in Paul Pumpens, Peter Pushko, Philippe Le Mercier, Virus-Like Particles, 2022
Paul Pumpens, Peter Pushko, Philippe Le Mercier
The HCV VLPs that were produced in mammalian cells using an adenovirus-based system generated particles that were reported to resemble the native virions morphologically (Chua et al. 2012; Kumar et al. 2016). The immunization of mice with these adenovirus-derived HCV VLPs in combination with adjuvants led to significant antibody response (Chua et al. 2012). In a heterologous prime-boost strategy, immunization with recombinant adenoviruses encoding the HCV structural proteins as a final booster, following priming with the HCV VLPs, resulted in enhancement of both antibody and T-cell responses (Kumar et al. 2016).
Adenoviral Vectors for Gene Therapy of Inherited and Acquired Disorders of the Lung
Published in Kenneth L. Brigham, Gene Therapy for Diseases of the Lung, 2020
David T. Curiel, Robert I. Garver
Recombinant adenovirus genomes are constructed from plasmid intermediates containing portions of the wild-type adenovirus genome. Berkner and Sharp first reported that large portions of the adenoviral genome could be propagated as a plasmid insert and later rejoined to produce a functional adenoviral genome (17). These initial strategies involved heterologous recombination between linear DNA segments. This initial observation was followed by subsequent refinements in the vector intermediates. In this regard, Graham and colleagues have produced the most widely used adenoviral vector system which is based on plasmid vectors which undergo recombination and that have convenient cloning sites for new coding sequences (as reviewed in 18).
Dopamine Receptors, Signaling Pathways, and Drugs
Published in Nira Ben-Jonathan, Dopamine, 2020
Receptor desensitization is defined as a time-dependent diminished responsiveness to a bound agonist that affects the dynamics, plasticity, and the overall activity of a given receptor. Desensitization protects against receptor overstimulation and enables the integration of a biological signal through feedback from second messengers [37]. Therapeutically, however, desensitization is viewed as a considerable impediment because it ultimately limits the efficacy of some drugs. Two types of desensitization modes have been recognized: homologous and heterologous [7]. Homologous desensitization refers to loss of response to an agonist that acts upon a specific receptor subtype, whereas heterologous desensitization refers to diminished responsiveness to a ligand resulting from input by signaling component(s) downstream of the receptor [38].
Current status of mucosal vaccines against SARS-CoV2: a hope for protective immunity
Published in Expert Opinion on Biological Therapy, 2023
Ileana García-Silva, Dania O Govea-Alonso, Sergio Rosales-Mendoza
Heterologous immunization is a strategy that is being studied to strengthen the initial immunity induced by the vaccines with emergency approval. A singular formulation based on the coadministration of a DNA vaccine targeting RDB expression fused to PD1 (an adjuvant component due to its role as immune check point) plus an influenza viral vector displaying the RBD antigen (LAIV-CA4-RBD) was developed by Zhou et al. [81]. Interestingly, in this study, the test vaccine was deemed as an effective booster of the immune response induced by the mRNA-based Pfizer/BioNTech vaccine currently used in humans. BALB/c mice were i.m. immunized with Coronavac (Sinovac) or Pfizer/BioNTech vaccines and i.n. boosted 3 weeks later with the DNA-based vaccine prototype. In contrast with homologous immunization, heterologous immunization (mainly in the Pfizer/BioNTech-LAIV-CA4-RBD scheme) led to a significant increase in IgG and IgA responses, as well as in neutralizing antibody levels from BAL. Moreover, significant increases in IFN-γ-producing T cells and tissue-resident memory CD8+ T cells in lungs were observed in mice receiving the heterologous boost. In addition, vaccination with the RBD DNA-based vaccine either in a heterologous or homologous scheme induced neutralizing activity against Beta and Delta SARS-CoV-2 variants.
Nanocurcumin formulation: a possible therapeutic agent for post COVID inflammatory syndrome
Published in Immunopharmacology and Immunotoxicology, 2022
Asha D. Kushwaha, K. P. Mishra, Mrinalini Singh, Lilly Ganju, Deepika Saraswat
Although specific COVID-19 vaccines have been released and given emergency use approval, they are still in limited supply and the slow pace of COVID-19 vaccination is a global challenge. It is likely to take many months to vaccinate the entire global population. The shortage of vaccine prompted to experiment with the heterogonous vaccine doses. Some researchers believe that heterologous immunization could potentially boost the immune response against the SARS CoV2 [9]. Heterologous immunization would mean following up one dose of a particular vaccine with a second dose of a different vaccine. Recently, a single case report demonstrated that individuals receiving an initial dose of Oxford-AstraZeneca covishield followed by a second dose of Pfizer-BioNTech vaccine elicit a robust humoral immune response against SARS-CoV-2 [10]. The significance of this study will be administering combination immunization to maximize vaccine distribution and coverage. Vaccine shortage and hesitancy for vaccine led to the wide spread of SARS CoV 2 infection. The different variants of the virus are also contributing to the high surge of second/third wave in many countries. Therefore, steps must now be taken to increase vaccine supply by ramping up the production capacities to relief COVID household stress [11,12] and also develop therapeutic agents to manage the post COVID complications in patients.
To mix or not to mix? A rapid systematic review of heterologous prime–boost covid-19 vaccination
Published in Expert Review of Vaccines, 2021
Nan-Chang Chiu, Hsin Chi, Yu-Kang Tu, Ya-Ning Huang, Yu-Lin Tai, Shun-Long Weng, Lung Chang, Daniel Tsung-Ning Huang, Fu-Yuan Huang, Chien-Yu Lin
Heterologous vaccination refers to the use of booster and priming vaccines developed with different platforms. Heterologous vaccination against COVID-19 should be considered under some circumstances. First, vaccine shortages and supply delays might occur. Although novel technology was introduced to manufacture these vaccines, the vaccine supply remains inadequate, and it will take time to produce enough vaccines for all global residents. A shortage of vaccines might result in delayed administration of the second dose. Timely second-dose administration remains a challenge in many countries, and only 1% of people in low-income countries have received full vaccination. The issue of vaccine equity and availability is a major concern. Furthermore, adenovirus-vector vaccine-related thromboembolic issues have attracted global attention and have changed vaccine policies in some areas [10]. For example, rare cases of blood clotting after ChAdOx1 (ChAd) vaccination have been reported, and since May 2021, the UK government has recommended that people younger than 40 years old seek an alternative vaccine. With this policy change, ChAd-primed people might receive different vaccines as a booster against COVID-19. Moreover, some patients may have serious adverse events after prime vaccination, such as anaphylaxis. In these cases, an alternative second vaccination should be recommended. Finally, the emerging variants of concern have drawn attention, and breakthrough infections have been reported [11]. Heterologous vaccination might provide better efficacy to combat COVID-19 variants [12,13].