Guiding new treatment strategies using induced pluripotent stem cells

Ivy Dick, Assistant Professor, University of Maryland School of Medicine

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Timothy Syndrome is the result of a single mutation in the gene which encodes for a voltage gated calcium channel known as Ca_V1.2.  

These channels are responsible for controlling the amount and timing of calcium entry into many cell types throughout the body.  

When a mutation occurs within one of these channels, calcium entry is altered, resulting in abnormal function of multiple organs including the heart and the brain. 

Our lab focuses on understanding exactly how each of these mutations changes calcium entry. By understanding the mechanisms which are disrupted, we are able to better predict treatment outcomes, as well as enable new treatment strategies for patients. 

Thus far, our ongoing research has uncovered a challenge in the use of currently available therapeutics. Specifically, we have found that the mechanism by which many mutations disrupt the channels results in a decrease in the efficacy of calcium channel blockers on the channels which harbor TS mutations, making these drugs less effective for TS patients. 

In order to get past this challenge, our lab is working to develop new approaches to treatment.  

We utilise induced pluripotent stem cells (iPSCs) to evaluate the efficacy of new treatment strategies. iPSCs are cells derived from a patient, which can be grown in culture and differentiated into any cell type. 

In our lab, we generate both cardiac cells and neurons out of iPSCs, allowing us to study the effects of Timothy Syndrome on both the heart and the brain. With these cells, we are testing novel therapeutic strategies based on reducing the number of channels harboring the TS mutations.

Overall, we aim to better understand the precise deficits in channel function that cause TS, and use these insights to guide new treatment strategies.