Technology

Applications

AntibodyArrays^TM  have many applications, including:

• Examining protein expression patterns,
• Studying protein posttranslational modifications, and
• Screening protein-protein interactions,

Advantages

AntibodyArrays^TM are especially suitable for the screening of protein-protein interactions. Compared to conventional techniques used to detect protein-protein interaction, such as the yeast two-hybrid system, the AntibodyArray ^TM assay offers clear advantages:

• Time: The experiment takes 5-6 hours, while a yeast two-hybrid assay can take weeks or months;
• Cost: An array costs less than $1,000, compared to a cost of thousands in labor and reagents for a yeast two-hybrid experiment;
• Accuracy: False positive rate is lower because an array assay detects interactions occurred in vivo. False negative rate is also lower because an array assay can detect modification-dependent interactions; and
• Ease of implementation:  No expensive equipment is needed and training of personnel is minimal, whilst a yeast two-hybrid assay demands familiarity with yeast genetics.

For screening of protein post-translational modifications such as phosphorylation, AntibodyArrays^TM are also very valuable due to their high throughput and the high quality of data.

Why Protein Array?

For a life scientist who either is interested in understanding how life works and how diseases are developed or is eager to find a cure for a disease, the fundamental question is: What really happens in a cell, the basic unit of life?

When a cell is exposed to an external (e.g. microorganism, drug or hormone) or internal (such as apoptosis) stimulus, the cell undergoes cell signaling processes that lead to changes in the cell's state. These changes are mostly mediated by proteins.  Researchers have spent enormous amounts of time and resources attempting to understand the cell signaling that occurs inside a cell. Although much progress has been made, the process of dissecting cell signaling has been painfully slow. One of the most important reasons is the lack of an effective tool for the study of cell signaling.

Then came DNA microarrays, the much touted revolutionary tool for studying gene expression. With the whole genome neatly arranged on a tiny glass slide, the potential seemed limitless. The result, however, has been disappointing. Researchers are increasingly questioning the interpretability and relevancy of those seemingly enormous data points generated from an array scanner. The basic problem is very simple. If genes can only function through encoding proteins, studying proteins must be more direct and more relevant. Although mRNA profiling with DNA microarrays may provide insight into how proteins work, this approach is often based on an assumption that mRNAs can serve as surrogates for proteins. If this assumption is wrong, as is often the case, a new approach is warranted.

Protein arrays such as AntibodyArrays^TM are the new approach.

What is an AntibodyArray^TM?

An AntibodyArray^TM is a type of protein array. It contains hundreds of high quality antibodies against well-studied proteins. These antibodies are immobilized on a nitrocellulose membrane, each at a predetermined position. The immobilized antibodies on the array retain their ability to recognize and capture their antigens as well as antigen-associated proteins. The proteins captured on the array can then be detected by immunoblotting.