Methods for preparing Bacillus anthracis protective antigen for use in vaccines (U.S. Patent Number 7,763,451)

The invention relates to improved methods of producing and recovering B. anthracis protective antigen (PA), especially modified PA which is protease resistant, and to methods of using of these PAs or nucleic acids encoding these PAs for eliciting an immunogenic response in humans, including responses which provide protection against, or reduce the severity of, B. anthracis bacterial infections and which are useful to prevent and/or treat illnesses caused by B. anthracis, such as inhalation anthrax, cutaneous anthrax and gastrointestinal anthrax.