Biological Threat Detection Via Host Gene Expression Profiling‪.‬

The task of detecting biological threats is far more complicated than monitoring for other weapons of mass destruction. Measuring and quantifying radiation and chromatographic profiles indicative of nuclear and chemical threats, respectively, are relatively straightforward compared with the detection of biological weapon threats amid the tremendous biological background that comprises our environment. Most of the current biological warfare and environmental agent detection systems in field use or under prototype development rely on structural recognition approaches to identify anticipated agents or rely on "gold standard" culture conditions. Such assays, based primarily on antibodies, are highly specific for anticipated targets but provide only partial information concerning the pathogenicity of the threat. Current systems the military has implemented for threat identification have performed with limited success. In fact, the Pentagon Inspector General has criticized the "Joint Biological Point Detection System" for erratic limited performance (1). In addition, it is unclear how such an approach is applicable to the civilian population, where mass deployment of point detectors is not a feasible solution. Even with ideal detectors, proximity to a biological threat does not guarantee infection or illness. For threats such as Bacillus anthracis, the ability to preemptively treat individuals who were near dissemination sources with antibiotics is an option, if the dissemination source can be identified. Of further concern, a report has been published of a B. anthracis vaccine strain that had been engineered by Russian scientists to resist tetracycline antibiotics (2), raising the possibility that a quinolone-resistant B. anthracis could emerge as a biological weapon threat. Thus, not all biological threats can be treated as readily as during recent events, and there is a critical need to be able to quickly discern those individuals who are ill as a result of a bioagent etiology and to yield insight to the severity of illness.