FragIT™
MicroSpin, MidiSpin & MaxiSpin
Creation of F(ab’)2 and Fc in under 30 min
Fragment from 0.5 to 100 mg of IgG
Fragmentation of IgG is typically associated with low yield, time consuming optimization and operation at low pH with loss of immunoreactivity as a consequence. With FragIT MicroSpin, IgG is cleaved into fragments within minutes while passing through the microspin column. The column comes pre-packed with the proteolytic antibody-specific enzyme, FabRICATOR, conjugated to agarose beads and will specifically only cleave IgG into pure F(ab’)2 and Fc fragments. Due to the high catalytic power of FabRICATOR when immobilized, the FragIt spin columns allow for fragmentation of up to 100 mg of IgG in as little as 15 minutes – all with a simple, 3-step protocol. After elution from the FragIT™ MicroSpin column, F(ab’)2 and Fc fragments can be separated with size exclusion chromatography or a protein A-conjugated column. Also F(ab) monomers can be obtained from the F(ab’)2/Fc fraction with a simple 60 minute protocol.
Click here for species specificity of FabRICATOR protease.
Pure F(ab’)2 fragments lower cross-reactivity
F(ab')2 antibody fragments are used in many applications or assays where the presence of the Fc region may cause problems. If antibodies are used for staining of a specific target in tissues like spleen, lymph or in peripheral blood preparations, cells with Fc receptors (macrophages, monocytes, natural killer cells and B lymphocytes) can bind to the Fc region of the antibody and cause a background staining in areas that do not contain any antigen.
F(ab')2 fragments may also be desirable for staining or binding to cell preparations in the presence of plasma since they cannot bind to complement, which would lyse the cells. The divalency of the F(ab')2 fragment enables it to cross-link antigens and hence makes it useful for rosetting, cellular aggregation and precipitation assays.
Click here to see the homogeneity of F(ab')2 fragments when digested with pepsin vs FabRICATOR.
Click here for a simple protocol for converting F(ab')2 to Fab fragments.