Immune-mediated approaches against COVID-19

Abstract

he coronavirus disease-19 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first reported in Wuhan, China in December 2019. Since then, it has spread globally, already infecting millions of people worldwide. As of 30 June 2020, 213 countries have reported COVID-19 cases, with a total number that reached above 10.3 million, the most being in the USA (2.6 million), Brazil (1.4 million), Russia (640 thousand), India (548 thousand) and UK (314 thousand). USA has the highest number of deaths (126 thousand) followed by Brazil (58 thousand), UK (44 thousand) and Italy (35 thousand). The worldwide case fatality rate across all communities is 4.9%. Coronaviruses (CoVs) are enveloped viruses entrapping non-segmented, positive-sense and single-stranded ribonucleic acid (ssRNA). Their genome size ranges from 26 to 32 kb, being the largest known RNA virus. SARS-CoV-2 3' terminus encodes structural proteins, including spike (S) glycoproteins 1,2 , membrane (M) glycoproteins 3 , as well as envelope (E) 4 and nucleocapsid (N) proteins 2,5 (Fig. 1). In addition to the genes encoding structural proteins, there are specific genomic regions encoding for viral proteins required for replication 6 , in addition to other non-structural proteins, such as the papain-like protease (PLpro) 7 and coronavirus main protease (3CLpro) 8. According to the Center for Disease Control and Prevention (CDC), the incubation period following infection is 2-14 days, with an estimated median of 5.1 days 9,10. However, cases with longer incubation of 24 days have been reported 11. The long incubation period is the primary reason for the massive infection, as it is mostly asymptomatic yet contagious 10. Although the estimated patients' age average is ~70, all age groups are susceptible to this virus. However, the elder population (>60) and people with comorbidities are more likely to develop severe symptoms upon infection 12. Much like previous CoVs, severe acute respiratory syndrome (SARS) and Middle East respiratory ryndrome (MERS), SARS-CoV-2 is predominantly infecting the lower airways, ranging from mild respiratory illness to severe acute respiratory syndrome and septic shock in advanced stages 6. The most commonly reported symptoms are fever, dry cough, dyspnea, fatigue and myalgia, which are early characteristics of the most frequent manifestation of SARS-CoV-2 infection, pneumonia 13-15. Physicians and pathologists

Functionalized TiO2 Nanotube-Based Electrochemical Biosensor for Rapid Detection of SARS-CoV-2

“…The S1 subunit of the S protein consists of a receptor binding domain (RBD) that has a high binding affinity towards the host angiotensin-converting enzyme II (ACE2) receptor present on the human cells; the S2 subunit mediates virus-host cell fusion and entry [ 14 ]. Importantly, the S protein is highly immunogenic and induces immune response to produce neutralizing antibodies as well as T-cell responses in SARS-CoV-2 infected individuals [ 15 ]. Functionally, binding of S-RBD to the hACE2 receptor is crucial for the entry of SARS-CoV-2 into human cells.…”

Blocking of the High-Affinity Interaction-Synapse Between SARS-CoV-2 Spike and Human ACE2 Proteins Likely Requires Multiple High-Affinity Antibodies: An Immune Perspective

“…Recently, several human-origin monoclonal antibodies with neutralizing capacity were isolated from convalescent patients, which were further tested in mouse models for their therapeutic potential against SARS-CoV-2 (12,(51)(52)(53)(54)(55)(56)(57). For several of these antibodies, the 3D structures are available (12,51,52,54,55,58).…”

COVID-19, Tourism, and Nepalese Leisure Travelers’ Willingness to Travel

“…Th ere have been several reports that show medical and pharmaceutical companies working tirelessly to come up with vaccines to boost the immune system. Targeting and strengthening immune system seems to the be the only primary and the most eff ective way to counter COVID-19 in a patient (see WHO, 2020d; Catanzaro et al, 2020;Florindo et al, 2020;Yazdanpanah, Hamblin & Rezaei, 2020;Felsenstein et al, 2020). Th e Oxford University's Jenner Institute and the Oxford Vaccine Group have been pioneering the eff orts towards the discovery of a safe, eff ective, and accessible vaccine against coronavirus (University of Oxford, 2020).…”