A Comprehensive Review of the Protein Subunit Vaccines Against COVID-19

Abstract

Two years after severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), in December 2019, the first infections were identified in Wuhan city of China. SARS-CoV-2 infection caused a global pandemic and accordingly, 5.41 million deaths worldwide. Hence, developing a safe and efficient vaccine for coronavirus disease 2019 (COVID-19) seems to be an urgent need. Attempts to produce efficient vaccines inexhaustibly are ongoing. At present time, according to the COVID-19 vaccine tracker and landscape provided by World Health Organization (WHO), there are 161 vaccine candidates in different clinical phases all over the world. In between, protein subunit vaccines are types of vaccines that contain a viral protein like spike protein or its segment as the antigen assumed to elicit humoral and cellular immunity and good protective effects. Previously, this technology of vaccine manufacturing was used in a recombinant influenza vaccine (RIV4). In the present work, we review protein subunit vaccines passing their phase 3 and 4 clinical trials, population participated in these trials, vaccines manufactures, vaccines efficiency and their side effects, and other features of these vaccines.

Evaluating the characteristics of patients with SARS-CoV-2 infection admitted during COVID-19 peaks: A single-center study

“…Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a severe acute respiratory syndrome, commonly known as coronavirus disease 2019 (COVID-19) [ 1 , 2 ]. The disease was first reported in January 2020 in Wuhan, China, and officially announced as a pandemic by the World Health Organization (WHO) in March 2020 [ 3 , 4 ].…”

Mucosal delivery of nanovaccine strategy against COVID-19 and its variants

“…The utilization of aluminum hydroxide as an adjuvant is common. CpG1018 and Matrix-M1 were also used as adjuvant 28 , 29 , 30 - Well tolerated compared to whole virus and viral vector vaccines and safely administered to immunocompromised people 29 , 30 - Expression system of protein influences quality and quality of protein subunit vaccines due to post-translational modification in mammalian cell 31 , 32 , 33 - Safely produced without having to handle viral particles 29 - Stable and do not require storage in low-temperature storage facilities 30 , 33 54 32% RNA - Lower immunogenicity and requirement of booster doses due to waning vaccine effectiveness 31 , 34 - Exhibits the highest efficacy to prevent symptomatic COVID-19 compared to other vaccines 35 - Requires carrier molecules (lipid- or polymer-based nanoparticles) to protect RNA from RNase degradation and increase efficacy 4 , 36 , 37 - Activation of innate immunity induces the type 1 interferon pathway, which degrades mRNA and inhibits translation of mRNA, leading to a decrease in the efficacy of the vaccine. Sequence optimization is required to improve efficacy 4 , 38 - No interaction with host-cell DNA, which does not lead to genomic integration and subsequent insertional mutagenesis (non-integrating platform) 4 , 31 - Naturally degraded without metabolic toxicy 37 - Activation of interferon signaling due to exogenous RNA induces inflammation 4 , 31 - High adaptability to new pathogens and variants due to scalability and ease of mass production through high yield of in vitro transcription.…”

Therapeutic and diagnostic applications of nanoparticles in the management of COVID-19: a comprehensive overview

“…A protein subunit that includes a particular production of the virus rather than a fundamental viral particle is utilized to cause immune reactions. Moreover, structure proteins, SARS-CoV-2, contain structural and non-structural proteins [ 150 ]. In Table 4 , you can observe the specifications of some SARS-CoV-2 vaccines in the advanced clinical development phase.…”