TY - JOUR
T1 - Antibody-Invertase Fusion Protein Enables Quantitative Detection of SARS-CoV-2 Antibodies Using Widely Available Glucometers
AU - Leonard, Elissa K.
AU - Aller Pellitero, Miguel
AU - Juelg, Boris
AU - Spangler, Jamie B.
AU - Arroyo-Currás, Netzahualcóyotl
N1 - Publisher Copyright:
© 2022 American Chemical Society. All rights reserved.
PY - 2022/6/29
Y1 - 2022/6/29
N2 - Rapid diagnostics that can accurately inform patients of disease risk and protection are critical to mitigating the spread of the current COVID-19 pandemic and future infectious disease outbreaks. To be effective, such diagnostics must rely on simple, cost-effective, and widely available equipment and should be compatible with existing telehealth infrastructure to facilitate data access and remote care. Commercial glucometers are an established detection technology that can overcome the cost, time, and trained personnel requirements of current benchtop-based antibody serology assays when paired with reporter molecules that catalyze glucose conversion. To this end, we developed an enzymatic reporter that, when bound to disease-specific patient antibodies, produces glucose in proportion to the level of antibodies present in the patient sample. Although a straightforward concept, the coupling of enzymatic reporters to secondary antibodies or antigens often results in low yields, indeterminant stoichiometry, reduced target binding, and poor catalytic efficiency. Our enzymatic reporter is a novel fusion protein that comprises an antihuman immunoglobulin G (IgG) antibody genetically fused to two invertase molecules. The resulting fusion protein retains the binding affinity and catalytic activity of the constituent proteins and serves as an accurate reporter for immunoassays. Using this fusion, we demonstrate quantitative glucometer-based measurement of anti-SARS-CoV-2 spike protein antibodies in blinded clinical sample training sets. Our results demonstrate the ability to detect SARS-CoV-2-specific IgGs in patient serum with precise agreement to benchmark commercial immunoassays. Because our fusion protein binds all human IgG isotypes, it represents a versatile tool for detection of disease-specific antibodies in a broad range of biomedical applications.
AB - Rapid diagnostics that can accurately inform patients of disease risk and protection are critical to mitigating the spread of the current COVID-19 pandemic and future infectious disease outbreaks. To be effective, such diagnostics must rely on simple, cost-effective, and widely available equipment and should be compatible with existing telehealth infrastructure to facilitate data access and remote care. Commercial glucometers are an established detection technology that can overcome the cost, time, and trained personnel requirements of current benchtop-based antibody serology assays when paired with reporter molecules that catalyze glucose conversion. To this end, we developed an enzymatic reporter that, when bound to disease-specific patient antibodies, produces glucose in proportion to the level of antibodies present in the patient sample. Although a straightforward concept, the coupling of enzymatic reporters to secondary antibodies or antigens often results in low yields, indeterminant stoichiometry, reduced target binding, and poor catalytic efficiency. Our enzymatic reporter is a novel fusion protein that comprises an antihuman immunoglobulin G (IgG) antibody genetically fused to two invertase molecules. The resulting fusion protein retains the binding affinity and catalytic activity of the constituent proteins and serves as an accurate reporter for immunoassays. Using this fusion, we demonstrate quantitative glucometer-based measurement of anti-SARS-CoV-2 spike protein antibodies in blinded clinical sample training sets. Our results demonstrate the ability to detect SARS-CoV-2-specific IgGs in patient serum with precise agreement to benchmark commercial immunoassays. Because our fusion protein binds all human IgG isotypes, it represents a versatile tool for detection of disease-specific antibodies in a broad range of biomedical applications.
UR - http://www.scopus.com/inward/record.url?scp=85133144163&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85133144163&partnerID=8YFLogxK
U2 - 10.1021/jacs.2c02537
DO - 10.1021/jacs.2c02537
M3 - Article
C2 - 35675509
AN - SCOPUS:85133144163
SN - 0002-7863
VL - 144
SP - 11226
EP - 11237
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 25
ER -