Bolstering the Front Line of Biological Warfare Response: Biological warfare agents pose more than a hypothetical threat to U.S. military servicemembers. Troops operate in hostile areas where they could come under attack from adversaries wielding bio-agents like anthrax and toxins. The first step in reacting to any such attack is knowing that it occurred. Quickly and accurately identifying the presence of airborne antigens can be difficult given their complexity, the presence of numerous similar microorganisms in the environment, and the fact that even minute quantities of a threat agent can cause infection.
The Department of Defense (DoD) employs antibody-based biosensors as its immediate tool for quickly detecting antigens-antibodies bind to antigens-but these sensors have functional limitations that can leave warfighters at risk. The two biggest liabilities involve stability and affinity. Stability refers to a sensor's ability to continue functioning as required over time and despite environmental conditions.
Affinity refers to the tightness of the bond between an antibody and an antigen; the higher the affinity, the more sensitive a biosensor is over a wider range of threats. Existing DoD biosensors, while effective, have restricted shelf lives, are quickly rendered inoperable by high temperatures and offer limited affinity.
DARPA launched the Antibody Technology Program (ATP) in 2009 to address the technological limitations of current antibody-based biosensors. The program set out with two primary goals: achieve revolutionary improvements in the stability of antibodies over time, even in extreme conditions; and control affinity in biosensors to enable detection of numerous antigens by a single unit.
