From the President: What’s ZAP?

Wuzzup? No. What’s ZAP? Some of our products have SAP in the name, like 192-IgG-SAP (Cat. #IT-01). Some of our products have ZAP in the name, like Hum-ZAP (Cat. #IT-22).

First, what’s the same about ZAP and SAP? They both mean Saporin. The payload that Advanced Targeting Systems made famous to specifically eliminate targeted cells. For those of you new to this techology, Saporin is a ribosome-inactivating protein (Fig. 1).

Fig. 1  Saporin is obtained from the seeds of the Soapwort plant (Saponaria officinalis).  Saporin is a plant enzyme with N-glycosidase activity that depurinates a specific nucleotide in the ribosomal RNA 28S, thus irreversibly blocking protein synthesis.  It belongs to the well-characterized family of ribosome-inactivating proteins (RIPs). 

Now, what’s different about ZAP and SAP? The difference is in what the conjugate can do. A SAP conjugate has two components: 1) Saporin and 2) A targeting agent that is recognized on the cell surface and internalized. A ZAP conjugate has two components: 1) Saporin and 2) A non-specific agent that is NOT recognized on the cell surface and internalized (e.g. a secondary antibody, nonspecific peptide, or streptavidin).

If you want to make a saporin conjugate with your cell surface targeting agent, check out our ZAP products: ZAP Internalization Kits (Z-Kits) and Streptavidin products (see Page 7 for more information).

Fig. 2. The difference between SAP conjugates and ZAP conjugates. SAP conjugates target and eliminate specific cells.  ZAP conjugates need a primary targeting agent to be internalized.