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Binding affinities of human IgG1 and chimerized pig and rabbit derivatives to human, pig and rabbit Fc gamma receptor IIIA.

ABSTRACT: While pigs and rabbits are used as models for human immune diseases, Fc?R binding is poorly characterized in both test species. To evaluate antibody binding to Fc?RIIIA, a receptor involved in antibody-dependent cellular cytotoxicity, chimerized antibodies were generated by grafting the variable regions of a human IgG1 onto scaffolds from both species. The affinities of the parent and chimeric antibodies to the Fc?RIIIA proteins from all three species were determined. While the human IgG1 and rabbit IgG had similar affinities for each Fc?RIIIA with notable differences across species, pig IgG1 only bound pig Fc?RIIIA with appreciable affinity. Also, the functional pig and rabbit proteins described here can be used in future experiments, such as pharmacology and mechanism of action studies.

SUBMITTER: Bhatti MM

PROVIDER: S-EPMC6641210 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Binding affinities of human IgG1 and chimerized pig and rabbit derivatives to human, pig and rabbit Fc gamma receptor IIIA.

Bhatti Maryam M MM Cai Allen G AG Theunissen Jan-Willem JW

PloS one 20190719 7

While pigs and rabbits are used as models for human immune diseases, FcγR binding is poorly characterized in both test species. To evaluate antibody binding to FcγRIIIA, a receptor involved in antibody-dependent cellular cytotoxicity, chimerized antibodies were generated by grafting the variable regions of a human IgG1 onto scaffolds from both species. The affinities of the parent and chimeric antibodies to the FcγRIIIA proteins from all three species were determined. While the human IgG1 and ra ...[more]

PMID: 31323052

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