Coronaviruses represent a family of viruses named for their crown-like appearance in the electron microscope. They are the pathogenic agents for various illnesses such as the common cold, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome (MERS). In December 2019, a new coronavirus was identified as the cause of a disease outbreak that originated in China. It was named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In March 2020, the World Health Organization (WHO) declared the coronavirus disease (COVID-19) outbreak a pandemic. COVID-19 is highly infectious, transmitted primarily through direct contact with an infected person by droplets from sneezing or coughing. Symptoms of the COVID19 disease include, but are not limited to tiredness, dry cough, high fever, and difficulty breathing. The standard method for COVID-19 detection for the initial phase of the pandemic has been the qRT-PCR diagnostic test. The inconsistency of the technique and, more important, its ability to detect only current infections highlight the imperative move to serological testing for controlling the COVID-19 pandemic.
Serology tests are blood-based tests that can be used to identify whether people have been exposed to a pathogen by looking at their immune response (i.e. presence of antibodies against the pathogen). In contrast, the qRT-PCR tests currently being used to diagnose cases of COVID-19 can indicate only the presence of viral material during infection; they will not identify individuals who were infected and subsequently recovered. Serology tests can provide valuable information on the prevalence of a disease in a population by identifying individuals who have developed antibodies to the virus. There are many types of serological tests, such as enzyme-linked immunosorbent assays (ELISAs) and lateral flow assays (LFAs). LFAs are typically portable devices that provide qualitative (positive or negative) results and are widely available. Due to the rushed approvals of COVID-19 diagnostic assays, the usefulness of many LFA devices is questionable, given the lack of official performance validation with respect to sensitivity (how many true positives are detected) and specificity (the proportion of false positives). For these reasons, LifeSensors has chosen to join the fight against COVID-19 by providing tools for laboratory-based serological detection.
LifeSensors’ Serological Diagnostic Kits
Utilizing its proprietary SUMO expression platform, LifeSensors successfully expressed SARS-CoV proteins in 2002 and 2005. Fifteen years later, using the same strategy, LifeSensors expressed several SARS-CoV-2 proteins for supply purposes but, more important, as components of its COVID-19 serological kits, thereby ensuring its own supply chain. The detection kits use high throughput plates that are pre-coated with SARS-CoV-2 nucleocapsid protein, which traps antibodies targeting SARS-CoV-2 when incubated with patient serum. Incubation with a detection antibody that binds specifically to human antibodies generates a colorimetric or a chemiluminescent signal, thus, confirming exposure to the virus. LifeSensors has developed a COVID-19 IgG ELISA Diagnostic Kit dedicated to the detection of the long-term serological antibody sub-type, IgG. In addition, the LifeSensors team is developing a COVID-19 Total Antibody ELISA Detection Kit that will simultaneously detect IgG, IgM, and IgA antibodies against the SARS-CoV-2 nucleocapsid protein. The main advantage of the latter test is its ability to detect signs of viral infection regardless of the infection stage at the time of testing.
In summary, LifeSensors diagnostic technology presents several advantages:
- Rapid Results (within 90 minutes).
- High Sensitivity. Detection of viral antibodies at low femtomolar concentrations.
- Detection of present and past infection.
- High throughput. Analysis of 16 samples at 2 different dilutions.
- Compatible with simple plate readers available in every laboratory.
- Very affordable. Discounts available for bulk orders.
Our Vision for COVID-19 Diagnostics
Currently, LifeSensors is investing considerable energy and expertise developing COVID-19 diagnostic kits capable of confirming present/past infections. That information, combined with contact tracing, enables efficient quarantine and isolation behavior that will ultimately decrease the SARS-CoV-2 transmission rate. More important, the LifeSensors team recognizes that the ultimate game changer in the fight against COVID-19 will be an assay that establishes immunity to the infection. Since not all antibodies produced in response to viral infection represent protective antibodies, the research community must develop a technology to detect such macromolecules in the serum. If successful, such technology will have significant ramifications on population health as well as on the economy, since individuals deemed to be immune for SARS-CoV-2 will be free to resume their pre-COVID-19 lifestyle.