Recombinant SARS-CoV-2 Antibody Standards for Diagnostic Assays

We’re excited to introduce recombinant SARS-CoV-2 antibody standards for use in developing COVID-19 diagnostic assays. The standards contain equal amounts of anti-SARS-CoV-2 antibodies in four key isotypes and subtypes, for use as precisely defined controls and calibrators in coronavirus diagnostic tests.

Recent papers describe a diverse isotype and subtype pattern in SARS-CoV-2 seroconversion, with involvement of IgG1, IgG2, IgG3 and IgG4 (although IgG1 and IgG3 dominate), as well as IgM and IgA. More in-depth analysis of immune responses to SARS-CoV-2 requires precisely calibrated assays that remain accurate across a wide range of antibody concentrations. To address this need, Absolute Antibody has developed ISOblend™ standards.

Our ISOblend™ standards contain anti-SARS-CoV-2 antibody in human IgG1, IgG3, IgM and IgA formats, formulated at equal amounts (250 µg/ml each). The standards enable the precise calibration of assays seeking to quantify the abundance of the main antibody types induced in COVID-19. In particular, these controls enable more precision in the determination of both absolute and relative antibody abundances.

We offer three ISOblend™ standards, each using a different anti-SARS-CoV-2 antibody:

• Anti-spike glycoprotein [non-neutralizing, clone CR3022]
• Anti-receptor binding domain (RBD) [neutralizing, clone Sb#15]
• Anti-nucleocapsid [clone CR3009]

Each standard is conveniently pre-mixed to provide absolutely defined protein concentration and formulation. In addition, all antibody isotypes and subtypes are recombinantly produced to ensure long-term batch-to-batch reproducibility and high antibody purity.

While our three ISOblend™ standards are available to order off-the-shelf, we can also create custom recombinant standards with other antibody clones. In addition, the formats used within the standards can be purchased individually, along with further engineered formats such as human IgG2 and IgG4, antibody fragments, and species such as rabbit, mouse and cat.

Please contact us with any questions, to receive an order quote, or to discuss a custom project.