Danielle: Aptamer Selection Against Immunoglobulin E with the Possibility to Treat Allergic Response

Danielle Hoyer

Nucleic Acid Aptamer Selection Against Immunoglobulin E with the Possibility to Treat Allergic Response

Full Proposal can be found here

Progress Report 1 can be found here


Progress Report 2 can be found here.

Final Report can be found here

Abstract

            Seasonal allergies affect an estimated 40 million people in the United States (CDC 2003) and symptoms range from manageable in day-to-day life to life threatening if unprepared. Immunoglobulin E (IgE) is an antibody found in humans that plays a large role in allergic response. This allergic response includes IgE also is involved in other allergies such as latex, animals and food. For the purposes of this research project, the application towards seasonal allergies will be the focus. Currently there are many over the counter and prescription methods to prevent the symptoms of allergies, but these all work at either decreasing symptoms after their onset or desensitizing one to the effects of an allergen and neither are 100% effective.

The most effective method of treating allergies would be to treat further upstream at the receptor site. This would make the treatment usable for all different allergy reactions that are associated with IgE and its receptors.  An aptamer that binds to IgE prior to exposure to the allergen could disable the cascade of events that culminate in the varying degrees of symptoms. The ideal aptamer would bind to the FC region of IgE so it would be universal to all allergens. This aptamer could either bind to IgE could inhibit the allergens from binding or deliver a death message to the IgE, thus eliminating the allergic response entirely.

Specific Aim 1: Identify an RNA aptamer against IgE, specifically the FC (non-variable) region of IgE. The method for discovering said aptamer is through a series of steps otherwise known as SELEX. The precise methods of selection are detailed in the Experimental Design, Methods and Materials section.

Specific Aim 2: Develop an aptamer therapeutic against allergies. Depending on the nature of the previously developed aptamer it would take effect after the IgE has bound to the mast cell, but it would prevent an allergen from binding to IgE (See Figure 1). The aptamer may inhibit the binding of allergens to the IgE, or the more likely method would be to attach a death signal to the aptamer, which would cause the bond between IgE and its receptor on the mast cell to break.

The Human IgE used in the subsequent experiments will be obtained from MyBioSource, their contact number is 1-888-627-0165 and fax number is 1-858-633-0166. The catalog number is MBS318211. The unit price is $500.00 for 100 mg. By using a low protein to RNA ratio (200 pmols of antibody per round) this amount can last for at least six rounds of selection, more if the stringency of selection is increased and less is used per round. This will make the price per round of selection approximately $84.00. 

References

“CDC Fast Facts A-Z,” Vital Health Statistics, 2003

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