An Innovative PTD-IVT-mRNA Delivery Platform for CAR Immunotherapy of ErbB(+) Solid Tumor Neoplastic Cells

• Published in: Biomedicines Vol. 10; no. 11; p. 2885
• Main Authors: Georgiou-Siafis, Sofia K, Miliotou, Androulla N, Ntenti, Charikleia, Pappas, Ioannis S, Papadopoulou, Lefkothea C
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.11.2022; MDPI
• Subjects: Adenocarcinoma; Antigens; Cancer cells; Cancer therapies; Care and treatment; CD28 antigen; Cell death; Cell surface; chimeric antigen receptor (CAR) immunotherapy; Chimeric antigen receptors; Clinical trials; Cytokines; Cytotoxicity; delivery; Effector cells; ErbB protein; FDA approval; Genetic aspects; Genetic engineering; Genomes; Immunotherapy; IVT-mRNAs; Lymphocytes; Messenger RNA; Metabolism; Metastases; mRNA; Mutagenicity; NK-92 cells; Oral carcinoma; Patients; Pediatrics; Physiological aspects; protein transduction domain (PTD); PTD-IVT-mRNAs; Remission (Medicine); Severe acute respiratory syndrome coronavirus 2; Signal transduction; Solid tumors; Surface antigens; Transfection; Tumor cell lines; Tumors; United Kingdom; United States > US
• ISSN: 2227-9059; 2227-9059
• DOI: 10.3390/biomedicines10112885

Chimeric antigen receptor (CAR) immunotherapy includes the genetic modification of immune cells to carry such a receptor and, thus, recognize cancer cell surface antigens. Viral transfection is currently the preferred method, but it carries the risk of off-target mutagenicity. Other transfection platforms have thus been proposed, such the in vitro transcribed (IVT)-mRNAs. In this study, we exploited our innovative, patented delivery platform to produce protein transduction domain (PTD)-IVT-mRNAs for the expression of CAR on NK-92 cells. CAR T1E-engineered NK-92 cells, harboring the sequence of T1E single-chain fragment variant (scFv) to recognize the ErbB receptor, bearing either CD28 or 4-1BB as co-stimulatory signaling domains, were prepared and assessed for their effectiveness in two different ErbB(+) cancer cell lines. Our results showed that the PTD-IVT-mRNA of CAR was safely transduced and expressed into NK-92 cells. CAR T1E-engineered NK-92 cells provoked high levels of cell death (25–33%) as effector cells against both HSC-3 (oral squamous carcinoma) and MCF-7 (breast metastatic adenocarcinoma) human cells in the co-incubation assays. In conclusion, the application of our novel PTD-IVT-mRNA delivery platform to NK-92 cells gave promising results towards future CAR immunotherapy approaches.