Viral Vectors

We primarily employ integrating lentiviral and retroviral vectors, as well as non-integrating adeno-associated virus (AAV)-based particles for gene delivery.

For example, we used lentiviral vectors to generate a cyclinB1-eGFP-dependent reporter iPSC line to track proliferating cells. This tool allowed us to isolate and analyze living, proliferating iPSC-derived cardiomyocytes, providing insights into their differences from non-proliferating counterparts. Another example is our use of lentiviral vectors to validate the role of the RNA-binding protein quaking 5 in doxorubicin-induced cardiotoxicity – an acute pathology with high mortality and a significantly increased risk of heart failure over decades.

Adeno-associated viruses (AAV) are versatile viral vectors widely used in gene therapy and biomedical research for the targeted gene delivery.

We employ AAV vectors in various applications to explore innovative treatment approaches for cardiovascular and fibrotic diseases. For example, we use AAV-based overexpression to modulate cellular processes in disease models. This includes various coding and non-coding RNAs, which have shown protective cardiovascular and anti-fibrotic effects.

One major disadvantage of natural serotypes of AAV is their broad tropism. It results in undesired gene expression in non-target organs, which reduces therapeutic efficacy. Higher doses are often required to achieve sufficient gene delivery to target tissues, increasing the risk of toxicity in off-target organs (e.g., liver toxicity in high-dose AAV therapies). To overcome this problem, we work in close collaboration with Prof. Büning (Institute of Experimental Hematology) to develop engineered AAV capsid variants with peptide insertions that enable precise targeting of cardiomyocytes and cardiac fibroblasts in vivo. By leveraging various AAV capsid libraries (from Prof. Büning), we aim to enhance the specificity of gene delivery, minimizing off-target effects and improving therapeutic efficacy.

Through these approaches, we strive to advance the precision and safety of AAV-mediated gene therapies in the cardiovascular field. By optimizing vector design, delivery mechanisms, and transgene expression, we contribute to the development of innovative therapeutic strategies that have the potential to improve patient outcomes and pave the way for more effective and targeted treatments of cardiovascular diseases and beyond.

Key references:

Costa, A, Hunkler, HJ, Chatterjee, S, Cushman, S, Hilbold, E, Xiao, K, Lu, D, Leonardy, J, Juchem, M, Sansonetti, M, Hoepfner, J, Thum, T, Bär, C. (2024) A reporter system for live cell tracking of human cardiomyocyte proliferation. Cardiovascular Research, 120(14), 1660–1663. https://doi.org/10.1093/CVR/CVAE175

Gupta, SK, Garg, A, Bär, C, Chatterjee, S, Foinquinos, A, Milting, H, Streckfus-Bomeke, K, Fiedler, J, Thum, T. (2018) Quaking Inhibits Doxorubicin-Mediated Cardiotoxicity Through Regulation of Cardiac Circular RNA Expression. Circulation Research, 122(2), 246–254. https://doi.org/10.1161/CIRCRESAHA.117.311335

Rode L, Bär C, Groß S, Rossi A, Meumann N, Viereck J, Abbas N, Xiao K, Riedel I, Gietz A, Zimmer K, Odenthal M, Büning H, Thum T. (2022) AAV capsid engineering identified two novel variants with improved in vivo tropism for cardiomyocytes. Mol Ther. 30(12):3601-3618. https://doi.org/10.1016/j.ymthe.2022.07.003

Lu D, Chatterjee S, Xiao K, Riedel I, Huang CK, Costa A, Cushman S, Neufeldt D, Rode L, Schmidt A, Juchem M, Leonardy J, Büchler G, Blume J, Gern OL, Kalinke U, Wen Tan WL, Foo R, Vink A, van Laake LW, van der Meer P, Bär C, Thum T. (2022) A circular RNA derived from the insulin receptor locus protects against doxorubicin-induced cardiotoxicity. Eur Heart J. 43(42):4496-4511. https://doi.org/10.1093/eurheartj/ehac337

Chatterjee S, Hofer T, Costa A, Lu D, Batkai S, Gupta SK, Bolesani E, Zweigerdt R, Megias D, Streckfuss-Bömeke K, Brandenberger C, Thum T, Bär C. (2021) Telomerase therapy attenuates cardiotoxic effects of doxorubicin. Mol Ther. 29(4):1395-1410. https://doi.org/10.1016/j.ymthe.2020.12.035

Viereck J, Bührke A, Foinquinos A, Chatterjee S, Kleeberger JA, Xiao K, Janssen-Peters H, Batkai S, Ramanujam D, Kraft T, Cebotari S, Gueler F, Beyer AM, Schmitz J, Bräsen JH, Schmitto JD, Gyöngyösi M, Löser A, Hirt MN, Eschenhagen T, Engelhardt S, Bär C, Thum T. (2020) Targeting muscle-enriched long non-coding RNA H19 reverses pathological cardiac hypertrophy. Eur Heart J. 41(36):3462-3474. https://doi.org/10.1093/eurheartj/ehaa519