Targeting Talk: Cytotoxicity Assay Protocols

One of the tests you can use to test your targeting agent for internalization is the in vitro Cytotoxicity Assay. Protocols to assist in preparing for, executing and interpreting results are now posted on our website. (see Protocol listing)

There are several protocols available.

  1. Preparing for a Cytotoxicity Assay using Secondary Conjugates. This protocol will be helpful when using our secondary antibody-saporin conjugates with your primary antibody. These include Anti-M-ZAP (Cat. #IT-30), Goat-ZAP (Cat. #IT-36), Hum-ZAP (Cat. #IT-22), Mab-ZAP (Cat. #IT-04), Rab-ZAP (Cat. #IT-05), and Rat-ZAP (Cat. #IT-26).
  2. Preparing for a Cytotoxicity Assay using Streptavidin-ZAP. This protocol will be helpful when using our streptavidin-saporin conjugate (Streptavidin-ZAP, Cat. #IT-27) with your biotinylated targeting agent (peptide, ligand, cytokine, growth factor, antibody, etc.).
  3. Concentration Calculation: Convert molarity to mg/ml and mg/ml to molarity. This protocol will help in determining the correct amount of material to use in your assay. There is also a link to an Online Calculator.
  4. Cytotoxicity Assay for Targeted Toxins in vitro. This protocol includes photos of what your plates should look like during the assay process. It takes five days to complete this assay. Start on a Monday and develop on Friday. There are many factors that go into a successful cytotoxicity assay. This protocol should help you design and execute appropriately.
  5. Preparing Cytotoxicity Data. This protocol will give an example of how to process the data from a Cytotoxicity Assay. ATS uses SOFTMax Pro software connected to a plate reader to determine the A490 value. Then we import this data into Prism software (GraphPad) to conduct further data analysis. Here is a figure generated with Prism.

This graph gives important information about how the potency of your targeted toxin. The ED50 is the Median Effective Dose (produces desired effect in 50% percent of population). The lower this number is, the more potent the targeted toxin.

We hope these protocols will be helpful to you in your research. If there are additional protocols or tutorials we can provide, please do not hesitate to ask.

See also: Protocols Listing, Targeted Toxins Catalog, Secondary Conjugates Catalog