Bio-Rad, HCA247, Human IgG4 | AbD18705_hIgG4_Pro

Recombinant Human IgG4 kappa (mutant), clone AbD18705_hIgG4_Pro is a recombinant human IgG4 antibody with a kappa light chain and a mutation S228P in the core hinge region. Clone AbD18705_hIgG4_Pro is specific for green fluorescent protein (GFP) and has no known reactivity with mammalian proteins or other antigens. This product is recommended for use as a standard in assays designed to measure IgG4 levels, or as a control antibody when using other human antibodies of the same isotype and subclass. In addition to the tetrameric IgG structure, composed of two copies each of the heavy and light chains, wild type human IgG4 forms so-called half-molecules. This species contains only one heavy and one light chain. Half-molecules can assemble with an unrelated half-molecule to form bispecific tetrameric antibody species ( Aalberse et al. 2002 ). Half-molecules of human IgG4 preparations can be detected as an additional species under denaturing, non-reducing conditions using SDS-PAGE, size exclusion chromatography or capillary electrophoresis. The serine to proline mutation at amino acid 228 in the core hinge region of IgG4 prevents the formation of half-molecules ( Bloom et al. 1997 ). Recombinant Human IgG4 kappa (mutant) does not display this additional species; half-molecules cannot be detected in SDS-PAGE or by size exclusion chromatography. In addition to the mutant recombinant, Bio-Rad also offers recombinant Human IgG4 kappa in its wild type form ( HCA195 ). Recombinant Human IgG4 lambda is also available in both wild type ( HCA050 ) and mutant form ( HCA246 ).

Storage Information
This product is shipped at ambient temperature. It is recommended to aliquot and store at -20°C on receipt. When thawed, aliquot the sample as needed. Keep aliquots at 2-8°C for short term use (up to 4 weeks) and store the remaining aliquots at -20°C.
Avoid repeated freezing and thawing as this may denature the antibody. Storage in frost-free freezers is not recommended.