SEASR Spotlight – Angel Sampson

A scientific poster titled “Cross-Core Collaboration towards the Characterization of AAV-Antibody Complex Structures” presented at the recent ABRF Annual Meeting in Myrtle Beach proved to be a winner! The lead author on the poster is SEASR member Dr. Angel Sampson, Scientific Director of the Monoclonal Antibody Core at the ICBR, University of Florida in Gainesville.  The work presented is an example of a successful cross-core collaboration with Dr. Sampson, Dr. Yanping Zhang in the ICBR Gene Expression Core and Paul Chipman in the ICBR Electron Microscopy Core, and Professor Mavis Agbandje-McKenna, Director of the UF Center for Structural Biology.  Dr. Mavis studies the feasibility of using Adeno-associated virus (AAV) as a vehicle to deliver gene therapy in humans. Many AAV serotypes exist that differ in tropism – the cell or tissue type(s) preferred by the virus for infection – making them valuable tools for targeting delivery of genetic material to specific cell types. AAV is ubiquitous in our environment, and thus many humans develop antibodies that destroy the virus, thereby inhibiting its use for therapy.  Monoclonal antibodies were developed in the ICBR MA core that recognize specific protein spikes on the surface of the AAV particle. Using Cryo Electron Microscopy, the ICBR EM core used these antibodies to help define the 3-dimensional structure of the virus particle. The ICBR Gene Expression core isolated and sequenced the gene regions encoding the Fab region of antibody molecule that specifically binds to the viral spike proteins. Using the Fab predicted protein sequence Dr. McKenna was able to generate 3-D protein structure models of the antibody-viral protein interaction. By studying the intricate molecular details of these AAV-antibody complex structures, Dr. McKenna hopes to be able to genetically engineer AAVs and make them less antigenic and invisible to the human immune system. This will facilitate the effective use of AAVs for gene therapy without the complication of viral particle destruction by pre-existing antibodies in patients.

The submitted poster made it through a rigorous review process for scientific merit by a panel of expert judges. During this judging process, Dr. Sampson was required to give a 5 minute presentation and answer questions. Upon being selected as the top poster, Dr. Sampson then gave a 10 minute oral presentation in front of the ABRF meeting attendees. She received a certificate and $500 travel award donated by the Waters Corporation. Congratulations to SEASR member Dr. Sampson!