2024 Investiture Information

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PhD Thesis Proposal: Andrew Chang



10:30am - 12:30pm ET


For info on how to attend this videoconference, please email andrew.y.chang.th@dartmouth.edu.

"Engineering enhanced protein solubility via high-throughput screening"


Recombinant biologics have a tendency to aggregate and form insoluble species that complicate manufacturing, reduce specific activity, and raise concerns regarding clinical safety (Roberts 2014). For example, interferon-β-1b (Betaseron®) is an aggregation-prone biotherapeutic used to treat multiple sclerosis, however only 40% of the E.coli expressed product is recoverable as a soluble fraction (Runkel, Meier et al. 1998). Recombinant interleukin-2 (IL-2) is another approved therapeutic where highly aggregated formulations have been found to illicit anti-drug antibodies (ADAs) in more than 50% of patients (Prummer 1997). As an increasing number of recombinant proteins are entering the clinic, it is necessary to address the widespread concerns of biologic aggregation and develop tools to help engineer enhanced solubility for these molecules. Here, we detail development of an in vivo fluorescence-based aggregation biosensor system that enables high-throughput screening of biologics with improved solubility characteristics. We show that this biosensor is highly sensitive for distinguishing between soluble maltose-binding protein (MBP) and insoluble variant MalE31, and can be further applied to screen a mutagenic library of aggregation-prone GFP for functional and enhanced-solubility variants.

Thesis Committee

  • Karl Griswold (Chair)
  • Margie Ackerman
  • Chris Bailey-Kellogg


For more information, contact Theresa Fuller at theresa.d.fuller@dartmouth.edu.