Phage Derived Receptor Scaffold

The risk of biological terrorism is significant because of the high potency, widespread availability, and ease of dissemination of some biological threat agents. The earliest recognition of a bioterrorist attack may be indicated only by the clinical manifestation of the intended disease which, in some cases, can take days to weeks to present itself. Furthermore, laboratory confirmation of the diagnosis requires additional time. Despite the rapid advances in the development of identification methods such as fluorescent polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA), sensors that continuously monitor for the first signs of exposure to biological threat agents are needed. Any monitoring device for the detection of biological threat agents requires a scaffolding probe as part of the sensing platform that is capable of binding the target agent. Many of the currently proposed monitoring devices utilize antibodies as the molecular recognition probe. A good antibody may be very selective in targeting a particular antigen; however, an antibody is a relatively fragile species whose binding characteristics rapidly degrade when exposed to unfavorable environments. Antibodies require affinity purification and stabilization for use as a scaffolding probe which significantly increases their cost. A stable, reproducible and inexpensive alternative to antibodies for use as a molecular recognition probe is needed. Phage possess many of the desirable features of antibodies and have been shown to serve as a substitute for antibodies by binding soluble and cell-displayed antigens and receptors. Phage may exhibit high affinity, increased specificity and selectivity, long term stability as well as enhanced robustness compared with antibodies. In this Phase I effort, a phage derived probe for spores of B. anthracis will be investigated and compared with commercially available antibodies with respect to its ability to serve as a receptor scaffold on a biosensor platform. Techniques for the immobilization of the phage derived probe onto a unique sensing platform will also be examined in a parallel effort.