COVID‐19 antibody screening with SARS‐CoV‐2 red cell kodecytes using routine serologic diagnostic platforms

Abstract

Background The Coronavirus disease 2019 (COVID‐19) pandemic is having a major global impact, and the resultant response in the development of new diagnostics is unprecedented. The detection of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has a role in managing the pandemic. We evaluated the feasibility of using SARS‐CoV‐2 peptide Kode Technology‐modified red cells (C19‐kodecytes) to develop an assay compatible with existing routine serologic platforms. Study Design and Methods A panel of eight unique red cells modified using Kode Technology function‐spacer‐lipid constructs and bearing short SARS‐CoV‐2 peptides was developed (C19‐kodecyte assay). Kodecytes were tested against undiluted expected antibody‐negative and ‐positive plasma samples in manual tube and three column agglutination technology (CAT) platforms. Parallel analysis with the same peptides in solid phase by enzyme immunoassays was performed. Evaluation samples included >120 expected negative blood donor samples and >140 COVID‐19 convalescent plasma samples, with independent serologic analysis from two centers. Results Specificity (negative reaction rate against expected negative samples) in three different CAT platforms against novel C19‐kodecytes was >91%, which correlated with published literature. Sensitivity (positive reaction rate against expected positive convalescent, PCR‐confirmed samples) ranged from 82% to 97% compared to 77% with the Abbott Architect SARS‐CoV‐2 IgG assay. Manual tube serology was less sensitive than CAT. Enzyme immunoassay results with some Kode Technology constructs also had high sensitivity. Conclusions C19‐kodecytes are viable for use as serologic reagent red cells for the detection of SARS‐CoV‐2 antibody with routine blood antibody screening equipment.

Erytra Blood Group Analyser and Kode Technology testing of SARS-CoV-2 antibodies among convalescent patients and vaccinated individuals

“…Red cells were coated with short peptides derived from the SARS-CoV-2 spike protein. 2,6 These red cells laden with artificial SARS-CoV-2 spike antigens (C19-kodecytes) behave like normal red cells bearing blood group antigens in routine antibody screening assays. We first investigated the performance of the C19-kodecyte assay against convalescent plasma donor samples.…”

“…[7][8][9] However, this rate was similar to the 91% specificity rate reported previously for the Grifols platform. 2,6 The samples from negative controls had not been tested with the virus neutralization assay, so a comparison was not possible.…”

“…C19-kodecyte reagent red cells were prepared as previously described. 2 In brief, the Kode constructs FSL-1147 and FSL-1255 were both dispersed in red cell stabilizer solution (ID-Cellstab 005650; Bio-Rad, München, Germany) at concentrations of 1.5 µmol/L and 2.5 µmol/L, respectively. The FSL-1147+1255 construct blend was incubated with washed packed group O red cells for 2 hours at 37 °C, then adjusted to 1 % using red cell stabilizer solution.…”

“…We recently developed C19-kodecyte reagent red cells suitable for routine manual and automated assays with the antiglobulin techniques available in most blood bank and hospital laboratories. 2,3 C19-kodecyte reagent red cells can be prepared in any laboratory within 2 hours by inserting Kode Technology constructs into the membranes of blood group O red cells. The C19-kodecytes are thus coated with 15 amino acid-long peptides derived from the SARS-CoV-2 spike protein attached to the red cell membrane by a spacer and a lipid.…”

Antibodies as Biosensors’ Key Components: State-of-the-Art in Russia 2020–2021

“…In continuation of the previous work, the possibility of using erythrocytes (C-19 kodecytes) modified using Kode-technology function-spacer-lipid constructs and carrying short SARS-CoV-2 peptides was assessed to develop an assay compatible with the existing routine serological platforms. It has been shown that C19-kodecytes are viable for use as erythrocytes of a serological reagent to detect SARS-CoV-2 antibodies using standard equipment for screening antibodies in the blood [95].…”