a chemical conjugate of goat anti-rabbit monovalent antibody
and the ribosome-inactivating protein, saporin

Secondary conjugates are conjugations of a secondary antibody to the ribosome-inactivating protein, saporin (from the seeds of the plant, Saponaria officinalis). Fab-ZAP uses your rabbit primary antibody to target and eliminate cells that recognize your primary antibody. Once Fab-ZAP is internalized, saporin breaks away from the targeting agent and inactivates the ribosomes, which causes protein inhibition and, ultimately, cell death.

Fab-ZAP is made with a monovalent secondary antibody eliminating the possibility of cap formation, while preserving all the qualities that make an effective in vitro diagnostic tool. It also has an improved ED50 when directly compared to Rab-ZAP in a cytotoxicity assay. This reagent can be utilized for screening rabbit IgG antibodies for internalization and/or their suitability to make potent immunotoxins.

Elimination of Specific Cell Type

• Cells that internalize your rabbit IgG antibody will be eliminated.
• Potency may vary according to the specificity and affinity of YOUR antibody to ITS antigen.
• Second immunotoxins are most effective in determining specificity of your antibody and suitability for conjugation as a primary immunotoxin.
• ATS recommends that you order a custom conjugation of your antibody to saporin when the in vitro results confirm the desired specificity.

Protocols: Preparing for a Cytotoxicity Assay; Preparing Test Samples

Available Control: The recommended control for use with this product would be a non-binding primary antibody, such as an isotype control, that mimics your primary antibody targeting agent. This control antibody should be used with Fab-ZAP identically to the manner in which you test your primary antibody of interest. However, as a convenient alternative, we do offer Goat IgG-SAP (Cat #IT-19) for use as a control toxin. Goat IgG-SAP is a non-binding immunotoxin made from pre-immune, bivalent IgG attached to saporin.