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Site-specific DNA-antibody conjugates for specific and sensitive immuno-PCR.

ABSTRACT: Antibody conjugates are widely used as diagnostics and imaging reagents. However, many such conjugates suffer losses in sensitivity and specificity due to nonspecific labeling techniques. We have developed methodology to site-specifically conjugate oligonucleotides to antibodies containing a genetically encoded unnatural amino acid with orthogonal chemical reactivity. These oligobody molecules were used in immuno-PCR assays to detect Her2(+) cells with greater sensitivity and specificity than nonspecifically coupled fragments, and can detect extremely rare Her2(+) cells in a complex cellular environment. Such designed antibody-oligonucleotide conjugates should provide sensitive and specific reagents for diagnostics, as well as enable other unique applications based on oligobody building blocks.

SUBMITTER: Kazane SA

PROVIDER: S-EPMC3309776 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Site-specific DNA-antibody conjugates for specific and sensitive immuno-PCR.

Kazane Stephanie A SA Sok Devin D Cho Edward H EH Uson Maria Loressa ML Kuhn Peter P Schultz Peter G PG Smider Vaughn V VV

Proceedings of the National Academy of Sciences of the United States of America 20120215 10

Antibody conjugates are widely used as diagnostics and imaging reagents. However, many such conjugates suffer losses in sensitivity and specificity due to nonspecific labeling techniques. We have developed methodology to site-specifically conjugate oligonucleotides to antibodies containing a genetically encoded unnatural amino acid with orthogonal chemical reactivity. These oligobody molecules were used in immuno-PCR assays to detect Her2(+) cells with greater sensitivity and specificity than no ...[more]

PMID: 22345566

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