Biotechnology and Bioengineering Tools in COVID-19 Diagnostics - CRISPR and Beyond

Advances in bioengineering and biotechnology are an urgent need of the hour because of the ongoing pandemic of COVID-19. Coronavirus disease 2019 or COVID-19 is caused by SARS-CoV-2 which is a strain of a coronavirus called SARS-CoV or Severe Acute Respiratory Syndrome Corona Virus. Globally, COVID-19 has claimed lives 1,575,810 and infected 69,239,671 people. In this direction, biotechnological and bioengineering endeavors have shown several promising results to control the pandemic, which are discussed in this mini review.

Worldwide governments are aiming for COVID-19 testing to available on a large-scale. COVID-19 diagnostics include detection based on antibodies and nucleic acids, which are the most prevalent forms of COVID-19 testing. Nucleic acid-based tests involve sample collection from nasopharyngeal, oropharyngeal, or respiratory regions are collected and subjected to RT-PCR (Reverse Transcriptase PCR) [1]. In this process, SARS-CoV-2 RNA is converted to cDNA (complementary DNA), then primers specific to 3 loci of the viral cDNA are used for amplification [2]. The loci are ORF1ab which is the open reading frame of viral RDRP or RNA-Dependent RNA Polymerase, envelope protein or E gene, and nucleocapsid or N gene (Verma 2020). Either a singleplex or a multiplex format of RT-PCR is used.

A frequent problem reported in COVID-19 testing is falsenegatives, hence complementation of RT-PCR with CT scans is recommended for efficient diagnosis of SARS-CoV-2 infection [3,4]. An improved and efficient version of RT-PCR testing of COVID-19 is the targeting of RdRp/helicase (Hel), spike (S), and nucleocapsid (N) genes of SARS-CoV-2 [5].

In antibody-based testing of COVID-19, immunoglobulins IgG, IgM, and IgA are probed by ELISA (Enzyme-Linked ImmunoSorbent Assay). These immunoglobulins are produced by the body as a defense response to viral entry and detected after different number of days following COVID-19 infection [2]. In addition to diagnostics, several groups have generated panels of antibodies against spike or S protein of SARS-CoV-2 which binds to human receptor ACE2 [6]. The antibodies neutralize S protein, hence preventing viral infection.

Another biotechnological advancement of COVID-19 testing is done by CRISPR-based methods where SARS-CoV-2 DNA Endonuclease-Targeted CRISPR Trans Reporter (DETECTR) uses CRISPR-Cas12 to detect COVID-19 [7]. Another COVID-19 detection process based on CRISPR uses recombinase-mediated polymerase pre-amplification of DNA or RNA which is a specific high-sensitivity enzymatic reporter unlocking (SHERLOCK) [8]. More methods based on CRISPR are developed to overcome the disadvantages of existing CRISPR-based tools for COVID-19 diagnosis.

In addition to the methods discussed above, there are other processes for COVID-19 diagnostics. Overall, a combination of biotechnological and bioengineering advances has led to the development of diagnostic and therapeutic interventions for COVID-19. Further research is needed to make them available to populations globally in a rapid, efficient, and inexpensive way to combat the pandemic.

None.

No conflicts of interest.

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