The need for population-wide screening for the detection of viral infections and individuals' immunity has surfaced as an urgent need in the last months. The effort to combat the COVID-19 pandemic while allowing economic and social activities to resume very much depends on such testing being available, affordable, and most importantly, reliable. It is clear now, that the only way to address the reliability aspect is by multiplexing several quantitative tests rather than simplistic qualitative solutions.
COVID-19 Serological Antibody Testing
Multiplexed Antibody (IgM, IgG1 & IgG3) Testing
Moreover, these tests may need to address several different types of tests such as infection diagnostics (viral load) immunity assessment (multiple antibodies) and characterization of the immune response (e.g. Cytokine expression).
The Challenges of Current Non-Multiplexed Antibody Tests:
Too Many False Positives:
Antibody testing is targeting the countless number of different molecular structures, due to the fact that each person's immune-system generates different antibodies. Thus, optimizing the test to eliminate all interference is challenging. In addition, there are four strains of Coronavirus that are responsible for 'common cold' and are widely spread (~30%) in the general population. Antibodies generated by the immune system to fight these 'benign' strains, may interfere with the test due to the similarities of these strains to SARS-CoV-2.
Too Many False Negatives:
Antibodies against SARS-CoV-2 are created to target one of the virus’ structural proteins (e.g. Spike protein). Coronavirus has 4 such structural proteins, so unless we detect antibodies against all 4, we will end up with false negatives.
Our Solution – Highly Multiplexed Antibody Test which Includes:
Detection of antibodies against all strains of Coronavirus thus eliminates False Positives by detecting antibodies that are not specific to SARS-CoV-2.
Targeted detection of 'Neutralizing Antibodies' (e.g. antibodies against Spike Protein Receptor Binding Domain) thus providing information on the individual's immunity likelihood.
Controls for other types of Non-Specific-Binding (NSB), thus flagging non-valid / erroneous results.
Detection of antibodies against all 4 structural proteins of SARS-CoV-2, thus eliminating False Negatives.
Detection of all relevant Antibody Isotypes (e.g. IgM, IgG1, IgG3, IgA) thus providing a comprehensive picture of the immune system response.