Abstract 4275: Combining circular RNA and a silicon membrane-based cell engineering approach to create CAR-Ts with membrane bound IL-2 and IL-12

Abstract Cell delivery is crucial for cell therapy and drug development, and we have developed a novel mechanoporation technology that allows efficient delivery of a wide range of cargoes to primary cells and cell lines. This technology uses a silicon membrane to temporarily deform cells, creating pores that enable cargo diffusion into the cells. Importantly, this method minimizes disruption to normal gene expression and maintains cellular integrity. It is compatible with various cell types and has been successfully applied in both cell therapy and drug discovery. At Portal, we have successfully delivered CRISPR/Cas9 RNPs, mRNAs, circular RNAs, and siRNAs into T cells, B cells, NK cells, and monocytes. For instance, we achieved over 85% GFP expression and B2M deletion in naive T cells after simultaneous delivery of mRNA and CRIRPR-RNPs. Additionally, we demonstrated the functional expression of a CD19 CAR and membrane-bound IL-2 by delivering two circRNAs. Early data from iPSCs and HSCs show significant potential for stem cell engineering and differentiation. Using a clinical-scale prototype, we have achieved delivery of over 1x109 T cells per minute, resulting in more than 50% knockout efficiency and 90% GFP expression after 7 days of T cell expansion.Our platform also addresses a major barrier to drug development by enabling the delivery of cargoes that are otherwise impermeable to cells, such as small molecules, peptides, PROTACs, DELs, antibodies, and probes. We have successfully delivered a variety of cargos with over 80% efficiency while maintaining high cell viability. The technology has been tested in several cell types, including cancer cell lines, human immune cells, and stem cells. The simplicity of the mechanical delivery method facilitates scalability and integration with liquid handlers for high-throughput applications. This enables rapid and automated screening of molecules previously incompatible with live cell assays, improving drug discovery efficiency. Overall, Portal’s technology offers a scalable, cost-effective solution with the potential to significantly advance both cell therapy and drug discovery. By reducing manufacturing time and cost, it seamlessly integrates into existing clinical and industrial equipment, supporting the development of next-generation cell-based treatments that could revolutionize the treatment of diseases with high unmet clinical needs. Citation Format: Armon Sharei, Zhihui Song, Sophia Hirsch, Eleni Rogers, Darby Kreienberg, Alec Barclay, Andrew Larocque, Anil Narasimha. Combining circular RNA and a silicon membrane-based cell engineering approach to create CAR-Ts with membrane bound IL-2 and IL-12 abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 4275.