Improved methods to analyze complex
networks of soluble cellular enzymes and receptors are central to modern
biotechnology. Here too, however, present day proteomic microarrays
have only marginal utility. In order for binding reactions to be
detected, the analytes must be artificially labeled. This greatly
restricts the flexibility and utility of the microarray, and little data of
value has ever been obtained by such methods.
Molecular
Pathways' proteomic microarrays (patent
pending) (text)
can function with unlabeled analytes.
As a result, samples can be directly applied to the microarray surface
quickly and with minimal processing. This enables complete biochemical
pathways to be rapidly analyzed at a level of detail that was not previously
possible.
The "tethered
antigen" concept:
An
antibody labeled with a first fluorescent dye is tethered to a reagent
antigen labeled with a second fluorescent dye. The antibody is
also tethered to a microarray surface.
When excess test antigens (not
shown) are not present, the reagent antigen and antibody bind.
Fluorescence resonance transfer between dye 1 and 2 detects this
binding. However if excess test antigen is present, this disrupts
the binding between the reagent antigen and the antibody. This
reduces the resonance transfer signal.
Note that this reagent is
reusable -- the microarray surface can be flushed with buffer and the
assay repeated.
A PowerPoint presentation with animated graphics, illustrating the
concept, can be downloaded
here.
