Biosensor system for the rapid detection of analytes

#The described invention relates in general to systems, devices, and methods for detecting various analytes in biological samples or other sample types, and more specifically to a biosensor-based system for detecting and identifying analytes of interest in real time based on the emission of a detectable signal when the biosensor reacts with an analyte of interest in a sample being tested.

#In generic terms, a biosensor is a system or device for the detection of an analyte that combines a sensitive biological component with a physicochemical detector component. The components of a typical biosensor system include a biological element, a transducer or detector element, and associated electronics or signal processors that display test results in a meaningful and useful manner. The biological element typically includes biological material such as tissue, microorganisms, organelles, cell receptors, enzymes, antibodies, nucleic acids, and the like that may be created by known biological engineering processes. The transducer or detector element works in a physicochemical manner (e.g., optical, piezoelectric, and/or electrochemical) that transforms the signal resulting from the interaction of the analyte with the biological element into another signal that can be more easily measured and quantified. Biosensors originated from the integration of molecular biology and information technology (e.g., microcircuits, optical fibers, etc.) to qualify or quantify biomolecule-analyte interactions such as antibody-antigen interactions. Considering that there is great demand for rapid, sensitive, easy-to-handle, and cost-effective detection tools for detecting infectious agents, pathogens or/and toxins in food (see, for example, Mead et al., Food Related Illness and Death in the United States, Emerging Infectious Diseases; Vol. 5, No. 5, September-October 1999 (607-625), which is incorporated by reference herein, in its entirety), there is an ongoing need for the utilization of biosensors in real-time, field-portable devices and instruments for the detection and identification of infectious agents, pathogenic microorganisms, toxins, and other contaminants in foods and many other items.

#The following provides a summary of certain exemplary embodiments of the present invention. This summary is not an extensive overview and is not intended to identify key or critical aspects or elements of the present invention or to delineate its scope.

#The accompanying drawings, which are incorporated into and form a part of the specification, schematically illustrate one or more exemplary embodiments of the invention and, together with the general description given above and detailed description given below, serve to explain the principles of the invention, and wherein:

#FIGS. 1a-b are illustrations of a first biosensor in accordance with an exemplary embodiment of the present invention, wherein Jurkat T cells have been engineered to produce aequorin and to express the transmembrane non-antibody signal transducing element IgGbp-CD3ζ;

#FIGS. 2a-b are illustrations of a second biosensor in accordance with an exemplary embodiment of the present invention, wherein MC/9 mast cells have been engineered to produce aequorin, and wherein the MC/9 cells express the native receptor FcεRI, which binds to the soluble non-antibody signal transducing element IgGbp-IgE;

#Exemplary embodiments of the present invention are now described with reference to the Figures. Although the following detailed description contains many specifics for purposes of illustration, a person of ordinary skill in the art will appreciate that many variations and alterations to the following details are within the scope of the invention. Accordingly, the following embodiments of the invention are set forth without any loss of generality to, and without imposing limitations upon, the claimed invention.

#The present invention relates in general to systems, devices, and methods for detecting various analytes in biological samples or other sample types, and more specifically to a biosensor-based system for detecting and identifying analytes of interest in real time based on the emission of a detectable signal when the biosensor reacts with an analyte of interest in a sample being tested. The engineered cells of the present invention are extremely sensitive and effective biosensors and because these biosensor cells have an intrinsic detection capacity, they provide a versatile system that can be readily adapted to detect a wide variety of different infectious agents or other targets by simply selecting alternative soluble detector (e.g., antibody) molecules with specificity for a particular pathogen or other target of interest. Furthermore, the system of this invention can be readily configured for multiplex detection of several infectious agents or other analytes in a single assay, providing for great flexibility and utility. The versatility of the present invention is derived from a unique combination of elements and in particular from the combination of a universal biosensor cell with a specific soluble detector (e.g., antibody). The universal biosensor cell has the capacity to respond to the presence of essentially any target molecule that can be recognized by the detector molecule. Because, in some embodiments, the detector or detector antibody is added to the system as a soluble factor, the system may be configured to detect an alternative target by simply selecting an appropriate alternate detector or detector antibody. The specificity of the disclosed system is determined by the detector molecule, which is selected based on its specificity and affinity for a target molecule that is characteristic of an infectious agent or other target analyte. The combination of this universal biosensor cell and soluble detector also enables the construction of multiplex assays by simply including a plurality of detector molecules (e.g., antibodies) within the test system, wherein the target molecules are selected based on their specificity for alternative infectious agents or other analytes.

#Genetic manipulation and modification of the biosensor cell types used with this invention typically involve the use of appropriately selected gene delivery vehicles that contain genetic elements that function efficiently in the cell type of choice. For example, it is useful to employ a promoter element that directs high level expression of introduced transgenes in the specific biosensor cell of choice. In an exemplary embodiment of this invention, such a promoter element may be derived directly from the biosensor cell itself and then used to express a transgene of interest. In another embodiment of this invention, an appropriate element may be determined empirically by comparing the function of alternative promoter elements in the context of alternative gene delivery vehicles in order to identify effective promoter, transgene, vector combinations for the cell type of choice. Transgenes such as the gene encoding a luminescent reporter protein may be introduced into the biosensor cell using standard techniques such as electroporation or chemical transfection reagents such as, for example, lipofectamine. Other genetic engineering methods known to those of ordinary skill in the art are also compatible with the present invention.