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LASIC: Light Activated Site-Specific Conjugation of Native IgGs.

ABSTRACT: Numerous biological applications, from diagnostic assays to immunotherapies, rely on the use of antibody-conjugates. The efficacy of these conjugates can be significantly influenced by the site at which Immunoglobulin G (IgG) is modified. Current methods that provide control over the conjugation site, however, suffer from a number of shortfalls and often require large investments of time and cost. We have developed a novel adapter protein that, when activated by long wavelength UV light, can covalently and site-specifically label the Fc region of nearly any native, full-length IgG, including all human IgG subclasses. Labeling occurs with unprecedented efficiency and speed (>90% after 30 min), with no effect on IgG affinity. The adapter domain can be bacterially expressed and customized to contain a variety of moieties (e.g., biotin, azide, fluorophores), making reliable and efficient conjugation of antibodies widely accessible to researchers at large.

SUBMITTER: Hui JZ

PROVIDER: S-EPMC5507662 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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LASIC: Light Activated Site-Specific Conjugation of Native IgGs.

Hui James Z JZ Tamsen Shereen S Song Yang Y Tsourkas Andrew A

Bioconjugate chemistry 20150612 8

Numerous biological applications, from diagnostic assays to immunotherapies, rely on the use of antibody-conjugates. The efficacy of these conjugates can be significantly influenced by the site at which Immunoglobulin G (IgG) is modified. Current methods that provide control over the conjugation site, however, suffer from a number of shortfalls and often require large investments of time and cost. We have developed a novel adapter protein that, when activated by long wavelength UV light, can cov ...[more]

PMID: 26057140

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