An Anthrax Anti-Toxin

UT Austin scientists George Georgiou, Brent Iverson and Jennifer Maynard engineered the world’s first treatment for inhalation anthrax, approved by the FDA in 2016. The drug binds to anthrax toxin and prevents it from harming the host’s cells. Earlier researchers had collected antibodies from mice infected with anthrax that bound to the toxin but not effectively enough to save the mice from death.  

To make stickier antibodies, Maynard – then a graduate student and now a faculty member – used a method Georgiou and Iverson helped develop, called directed evolution.  

1. Identify the gene that codes for the antibodies from infected mice. 

2. Create thousands of mutant daughters of this parent gene. Each is slightly different, because the genetic copying machine makes a predictable number of mistakes. 

3. Put these mutant genes into bacteria so they can produce a library of modified antibodies. 

4. Screen these antibodies to see which do the best at binding to the anthrax toxin.

5. Choose the genes that code for these improved antibodies as the parents for the next round of directed evolution. Repeat.