The chimera of S1 and N proteins of SARS-CoV-2: can it be a potential vaccine candidate for COVID-19?

INTRODUCTION: Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emerged as one of the biggest global health issues. Spike protein (S) and nucleoprotein (N), the major immunogenic components of SARS-CoV-2, have been shown to be involved in the attachment and replication of the virus inside the host cell. AREAS COVERED: Several investigations have shown that the SARS-CoV-2 nucleoprotein can elicit a cell-mediated immune response capable of regulating viral replication and lowering viral burden. However, the development of an effective vaccine that can stop the transmission of SARS-CoV-2 remains a matter of concern. Literature was retrieved using the keywords COVID-19 vaccine, role of nucleoprotein as vaccine candidate, spike protein, nucleoprotein immune responses against SARS-CoV-2, and chimera vaccine in PubMed, Google Scholar, and Google. EXPERT OPINION: We have focussed on the use of chimera protein, consisting of N and S-1 protein components of SARS-CoV-2, as a potential vaccine candidate. This may act as a polyvalent mixed recombinant protein vaccine to elicit a strong T and B cell immune response, which will be capable of neutralizing the wild and mutated variants of SARS-CoV-2, and also restricting its attachment, replication, and budding in the host cell.

Antibody detection assays for COVID-19 diagnosis: an early overview.

The ongoing pandemic of coronavirus disease 2019 (COVID-19) has not only commenced a global health emergency but also agitated various aspects of humanity. During this period of crisis, researchers over the world have ramped their efforts to constrain the disease in all possible ways, whether it is vaccination, therapy or diagnosis. Because the spread of the disease has not yet elapsed, sharing the ongoing research findings could be the key to disease control and management. An early and efficient diagnosis could leverage the outcome until a successful vaccine is developed. Both in-house and commercial kits are the preferred molecular tests being used worldwide in the COVID-19 diagnosis. However, the limitation of high prices and lengthy procedures impede their use for mass testing. Keeping the constant rise of infection in mind, the search for an alternative test that is cost-effective, simple and suitable for large-scale testing and surveillance is the need of the hour. One such alternative could be immunological tests. In the last few months, a deluge of immunological rapid tests have been developed and validated across the globe. The objective of this review is to share the diagnostic performance of various immunological assays reported so far in severe acute respiratory syndrome coronavirus 2 case detection. We consolidate the studies (published and preprints) related to serological tests such as chemiluminescence, enzyme-linked and lateral flow-based point-of-care tests in COVID-19 diagnosis and update the current scenario. This review aims to be an add-on in COVID-19 research and will contribute to congregation of the evidence for decision making.