Our proprietary non-gene editing shRNA-based technology
Short hairpin RNA-based platform
Manipulating protein expression to generate cells with a specific desired feature is one of the central goals of engineered cell therapy. Short hairpin RNA (shRNA) is a well-established approach to reduce protein expression by silencing genes in a process called RNA interference.
Short hairpin ribonucleic acids (shRNAs) are small pieces of non-coding RNA that downregulate gene expression post-transcriptionally. This downregulation allows for effective silencing of specific targets, without gene manipulation.
Proof-of-concept of this proprietary technology has been provided via clinical evaluation of two of our CAR T-cell candidates including:
- An allogeneic BCMA-targeting CAR T-cell candidate (CYAD-211), where the propriety technology was used to target CD3ζ to knock-down the TCR complex in order to prevent GvHD, and
- An autologous NKG2D-based CAR T-cell candidate (CYAD-02), where the propriety technology was used to target the NKG2D ligands (NKG2DL) MICA/B to prevent cell fratricide and improve cell persistence.
Optimization of a technology based on multiplexing of shRNAs
- While the knock-down of a single target has its benefits, the real potential of our technology relies in the multiplexing and the simultaneous knock-down of multiple targets in the same cell. For instance, multiple modifications are required to overcome the immunosuppressive TME and enhance cell persistence, and the immune checkpoints PD-1, LAG3, TIM3, and TIGIT are all obvious targets to overcome cellular exhaustion. Furthermore, to increase cell persistence of allogeneic CAR T-cells, rejection of the cells by the patient’s immune system must be avoided which requires downregulation of the genes encoding the human leukocyte antigen (HLA)-I and II
- We have therefore optimized novel microRNA-based scaffold where multiple shRNAs can be inserted into a single construct, allowing simultaneous downregulation of multiple target genes, allowing up to four target genes to be down-regulated simultaneously in a simple, safe, efficient and tunable manner
Our shRNA-platform provides a versatile approach to control gene expression and optimize function of T-cells.
- Ability to optimize CAR T-cell features, persistence, efficacy or ability to evade complex or immunosuppressive tumor microenvironments, or reduce alloreactivity of allogeneic cell therapies
- The plug-and-play design of our platform is designed to allow for swapping each target sequence without affecting performance, streamlining the generation of engineered adoptive T-cell therapies
- All-in-one vector approach where we focus on using a single vector to generate CAR T-cells within a single transduction step, to simplify the design and development of our cell therapy candidates. The all-in-one vector approach encodes for multiple components in addition to the CAR, including one or several shRNAs, cell selection marker and potential therapeutic add-ons such as cytokines
shRNA multiplexing offers the ability to design and develop next-generation, non-gene edited CAR T-cell therapies with any CAR across a broad array of targets.
Moreover, this approach could be developed for other types of cell therapies since it is not limited to the field of CAR T-cells and/or immuno-oncology.