Novel Methods to examine Virus Particles with Mass Spectrometry

In this project we propose to design and build a CDMS instrument to determine the DNA content of recombinant adeno-associated viral (AAV) vectors. AAV vectors have emerged at the forefront of gene therapy due to their lack of pathogenicity, relatively low immunogenicity and persistent gene expression in different tissue types. Allergan is particularly interested in using AAV vectors for Ocular drug delivery as it purchased Retrosense in 2016 that is a biotechnology company that is developing a game-changing gene therapy (AAV) to restore vision in patients suffering from blindness due to retinitis pigmentosa (RP) and advanced dry age-related macular degeneration (advanced dry-AMD). There are currently no FDA approved therapies to improve or restore vision in patients with these retinal degenerative conditions. The analytics to support AAV production are very limited and the hope is with this project that CD-MS will significantly advance Allergan's capabilities.
Electrospray ionisation provides a facile way of delivering large multimeric protein particles to the gas phase for analysis. Whilst ESI based mass spectrometry has proved hugely beneficial for biological and biomedical science, in particular in the study of large intact protein assemblies, 1 still some assemblies are so massive that they cannot be resolved using conventional MS methods.
CDMS is a single particle technique that gets around this. It is highly simple, and works by measuring the charge on a particle that passes through a tube, along
with the time it take the particle to traverse the tube. This charge will be some integer z multiplied by the fundamental unit of charge (e). The time it takes the particle to traverse the tube will be related to the m/z of the particle by the equation of motion and these two measurements can be combined to provide M the mass of the particle. The challenge to the design in in shielding the signal to be measured in the control electronics. Here this student will build a CDMS device (following the designs shown previously)2-3 and work with Allergan to apply it to study intact virus particles of therapeutic benefit.
In addition the student will learn and apply more conventional MS techniques and contrast the benefit of CDMS with the ease of use in a commercial environment.