Validation of Dried Blood Spot Sample Modifications to Two Commercially Available Covid-19 Igg Antibody Immunoassays

Abstract

Aim: Coronavirus disease 2019 antibody testing often relies on venous blood collection, which is labor-intensive, inconvenient and expensive compared with finger-stick capillary dried blood spot (DBS) collection. The purpose of our work was to determine if two commercially available anti-severe acute respiratory syndrome coronavirus 2 enzyme-linked immunosorbent assays for IgG antibodies against spike S1 subunit and nucleocapsid proteins could be validated for use with DBS. Materials & methods: Kit supplied reagents were used to extract DBS, and in-house DBS calibrators were included on every run. Results: Positive/negative concordance between DBS and serum was 100/99.3% for the spike S1 subunit assay and 100/98% for the nucleocapsid assay. Conclusion: Validation of the DBS Coronavirus disease 2019 IgG antibody assays demonstrated that serum and DBS can produce equivalent results with minimal kit modifications.

Evaluation of Dried Blood Spot Testing for SARS-CoV-2 Serology Using a Quantitative Commercial Assay

“…High concordance between antibody detection from serum/plasma versus DBS has been reported in studies using ELISA-type immunoassays and lateral flow immunoassays where sample dilution is adjusted for in DBS specimens to compensate for dilution due to filter card extraction [ 2 , 17 , 20 , 24 , 27 , 28 ]. One group analyzed DBS samples from 80 volunteers using an in-house-developed ELISA protocol.…”

“…Several parameters affect the amount of predicted elution from the filter cards [ 26 , 28 , 49 ]. The number of circles spotted with blood, the punch size, and the number of punches will determine the size of the surface area exposed to elution buffer.…”

“…These assays have demonstrated high specificity and sensitivity using serum/plasma. Although there have been preliminary studies evaluating DBS collection for anti-SARS-CoV-2 immunoassays, DBS serology tests have yet to be used on a widespread scale [ 2 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ]. Importantly, the majority of platforms evaluated have been for qualitative assays for antibodies against SARS-CoV-2, a potential gap should a quantitative option prove beneficial.…”

Dried blood spot‐based detection of serological profiles of hepatitis B and C infections and their prevalence in Cambodia

“…12 Beside viral hepatitis, in relation to new pandemic corona virus, it had been reported as the feasible tool for diagnosis of serological marker of SARS-CoV-2 infection. 18,19 All the aforementioned scientific findings suggest that DBS is useful for the serological and molecular surveillance and detection of seromarkers and viral proteins of even unknown virus or newly emerged virus in the future.…”

Development and Validation of a Multiplex Microsphere Immunoassay Using Dried Blood Spots for SARS-CoV-2 Seroprevalence: Application in First Responders in Colorado, USA

“…Elution of antibodies from the DBS requires only a simple buffered detergent and limited plasticware. Community samples obtained in this fashion have long been used to establish seroprevalence of infectious diseases (8,10,13,15), serving as an effective precedent for the use of DBS in SARS-CoV-2 seroprevalence studies (16)(17)(18)(19)(20)(21).…”