Gene Therapy Research

Image: Nucleosome, PDB ID 1AOI

The viral and bacterial DNA used in gene therapy is often condensed by histone proteins and sequestered into tightly packed heterochromatin after delivery to the nucleus, which ultimately leads to silencing of the delivered transgene(s).   Our goal is to prevent transgene silencing by inserting “enhancer” sequences into our plasmids that cause them to take on a more relaxed/open conformation (i.e. euchromatin) instead of heterochromatin.  

Image: NF-kb bound to DNA, PDB ID 1SVC

When foreign bacterial or viral DNA enters a cell, it can trigger a variety of defense mechanisms that include inhibition of translation/protein expression, transgene silencing, and/or apoptosis (cell death).  This innate immune response (IIR) presents a significant problem for most gene therapy treatments, since they utilize bacterial or viral DNA.  We are currently addressing this problem by (1) identifying the specific enzymes/proteins involved in the IIR, (2) inhibiting key parts of the IIR, and (3) hijacking proteins that are activated during the IIR and using them to boost transgene expression.  

Image: Cas9, PDB ID 4CMP

CRISPR/Cas9 technology has enabled researchers to easily mutate genes, but inserting a gene into the genome with Cas9 is still a challenging task (especially in T cells).  We aim to optimize every step in Cas9-mediated genome editing in T cells, from gene delivery to genomic insertion via homology directed repair, all with the ultimate goal of maximizing chimeric antigen receptor (CAR) expression in primary T cells.