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AI and Immunology Considerations in Pandemics and SARS-CoV-2 COVID-19
Published in Louis J. Catania, AI for Immunology, 2021
By definition, the traditional vaccine is a biological preparation that provides active, adaptive immunity to a particular infectious disease (e.g., SARS-CoV-2) by stimulating antibodies to the source of the infection. It typically contains an agent that resembles the disease-causing microorganism made from weakened or killed forms of the microbe (an attenuated virus), its toxins, or one of its surface proteins. The spike protein is the target for most of the COVID-19 vaccine human clinical trials and so research centers on how the immune system, particularly B- and T-cells, responds to the spike protein. B-cells are responsible for producing the antibodies that recognize SARS-CoV-2, while T-cells play an important role in supporting the development of the B-cell response (see Chapter 2).
Introduction to basic immunology and vaccine design
Published in Amine Kamen, Laura Cervera, Bioprocessing of Viral Vaccines, 2023
Alaka Mullick, Shantoshini Dash
When using a protein antigen, for instance, in the case of SARS-CoV-2, the Spike protein is an obvious choice since it is responsible for cell entry (Figure 3.16). The virus uses the spike protein to bind a cell surface protein, acetylcholine esterase 2 (ACE-2), to gain entry into the cell. Therefore, a neutralizing or protective antibody could be one that would disrupt this interaction reducing the ability of the virus to enter the target cell. While it is possible to use the entire spike protein, there are attempts to use just the part that interacts with the receptor, since in theory, it should be able to elicit the desired effect.
COVID-19 pathogenesis and host immune response
Published in Sanjeeva Srivastava, Multi-Pronged Omics Technologies to Understand COVID-19, 2022
Surbhi Bihani, Shalini Aggarwal, Arup Acharjee
SARS-CoV-2 and severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) are placed under the Betacoronavirus genus of the Coronaviridae family. The members of Coronaviridae are enveloped with positive-sense, single-stranded RNA viruses (Gorbalenya et al. 2020). Deep sequencing methods have identified that the full-length genomic RNA of SARS-CoV-2 is around ~30 kb long and comprises 14 open reading frames (Kumar 2020). The spike protein enables cellular entry of the virus by interacting with the host cell surface receptor, angiotensin-converting enzyme 2 (ACE2) (Wang et al. 2020). After the receptor-binding domain (RBD) of spike protein comes in close contact with host ACE2, it is subjected to proteolytic priming by a transmembrane serine protease—TMPRSS2—of the host, which is to enable efficient viral–host membrane fusion reaction (Hoffmann et al. 2020). Alternatively, receptor-mediated endocytosis of the viral particle followed by proteolytic priming of S protein by endosomal cathepsin L is another way of viral entry into the host cell (Hoffmann et al. 2020). Once the viral genome is released inside the host cell, ORF1a and ORF1ab are translated into polyproteins and are cleaved into nsps by host and viral proteases (nsp3 and nsp5 harbor papain-like and 3C-like protease domains, respectively) (Harrison, Lin, and Wang 2020). Nsp12 possesses the main RNA-dependent RNA polymerase activity and, with other nsps, forms the Replicase to enable replication of genomic and subgenomic RNAs (sgRNA) (Harrison, Lin, and Wang 2020). Structural and accessory proteins enable the assembly and egress of progeny virions and aid in viral replication and pathogenesis (Yoshimoto 2020). The viral entry and life cycle are summarized in Figure 7.1.
Application of Artificial Intelligence on Post Pandemic Situation and Lesson Learn for Future Prospects
Published in Journal of Experimental & Theoretical Artificial Intelligence, 2023
Priyanka Dwivedi, Achintya Kumar Sarkar, Chinmay Chakraborty, Monoj Singha, Vineet Rojwal
Transmission of the virus happens by binding the spike protein to the angiotensin converting enzyme 2 (ACE2) receptor. Initially spike proteins are primed with protease enzyme (TMPRSS2) which enhance the binding of spike protein with ACE2 (Hoffmann et al., 2020). This mechanism allows the complete entry of viruses into the cells. After that entry of the virus to the human body, it starts to infect the host cells. Replication of the virus happened at the cytoplasmic membrane region which was later transcribed (transcription) and translated. According to the WHO report, it is believed that human to human transmission of COVID-19 is due to droplet transmission and in some cases, airborne transmission is also possible (Morawska et al., 2020). Figure 1 depicts the schematic view of COVID-19.
COVID-19;-The origin, genetics,and management of the infection of mothers and babies
Published in Egyptian Journal of Basic and Applied Sciences, 2020
Hassan Ih El-Sayyad, Yousef Ka Abdalhafid
Camelids, such as alpacas and llamas are of medical importance due to producing a novel type of heavy chain-antibody specific for production single domain antibodies which are highly selective for different protein antigen. The extracted single domain antibodies can then be used either directly or as part of an engineered reagent. Single domain antibodies can be generated, purified, and directly used in prokaryotic expression system in large quantities as recombinant proteins or can be engineered to contain unique markers as reporters in cellular studies or in diagnostics [148]. During invasion of the human cells, the SARS-CoV-2 receptor-binding domain (RBD) of the spike protein binds to ACE2 receptor. Two nanobodies, H11-D4 and H11-H4, are created with high selective binding to BRD and block their crosslink their ACE2 after application of a naïve IIama single-domain antibody library and PCR-based maturation. The studies illustrate that nanobodies identify the same epitope, which overlaps with the ACE2-binding surface, illustrating the blocking of the RBD-ACE2 interaction [149].
Drying of Vaccines and Biomolecules
Published in Drying Technology, 2022
Bhaskar N. Thorat, Ayantika Sett, A. S. Mujumdar
Looking at the nature of urgency and the nature of the pandemic caused by COVID19 worldwide, scientists are setting speed records this time, hoping that vaccination is the world’s best chance to sustain against the pandemic. Henceforth, vaccines are being developed in different research laboratories in all over the world. The candidates for vaccine against COVID19 is based on viral spike protein (surface attached) because of its crucial role in viral infection. While writing of this manuscripts, several vaccine candidates have moved onto a fast track clinical trials. Several known candidates till date for COVID-19 depending on their platform is tabulated in Table 2.[98]