Labbe, Roman; (2025) Development of a lentiviral platform for the simultaneous transduction and activation of T lymphocytes for improved CAR T cell function. Doctoral thesis (Ph.D), UCL (University College London).

Text Roman Labbe - PhD Thesis - Development of a lentiviral platform.pdf - Accepted Version Access restricted to UCL open access staff until 1 November 2026. Download (4MB)

Abstract

Chimeric Antigen Receptor (CAR) T cell therapy has been successful in the treatment of haematological malignancies, with response rates of up to 90%. Multiple CAR T therapies have reached market authorisation increasing the demand for high-quality vector. To date, all commercially available CAR T cell therapies rely on an autologous cell source and on retroviral or lentiviral vector (LV) gene transfer. CAR T cell therapy manufacturing involves highly complex bioprocesses leading to high manufacturing costs, therefore limiting access for patients. A critical bioprocessing step is the activation of the isolated T lymphocytes to ensure high transduction and cell expansion efficiencies to reach the required therapeutic dose. This is typically achieved through mitogen receptor targeting using microbeads conjugated to anti-CD3 and anti-CD28 antibodies. Although effective, this technique can lead to T cell overactivation and cellular exhaustion. Recent efforts have been focusing on improving T cell activation profile and reducing cell differentiation, as these factors have been linked to better clinical outcomes. We have investigated the use of LV particles called LentiSTIM (patent number PCT/GB2016/050537), capable of engaging mitogen receptors to simultaneously activate and transduce target T cells. The mitogens are expressed in engineered HEK293T producer cell lines as membrane bound proteins and are packaged into the LV envelope during vector production. We tested LentiSTIM transduction of a clinically relevant anti-CD19 CAR construct, testing different mitogen combinations, to improve T cell phenotype and reduce overactivation. The LentiSTIM approach resulted in comparable transduction levels to conventional bead activation and LV transduction, with a lower activation and exhaustion profile. To test the activity, persistence and differentiation of the CAR T cells in vivo, we are investigating the killing potential of LentiSTIM transduced cells against conventional LV transduction in a humanised NSG MHC I/II KO murine model. Four groups of 10 mice will be engrafted with a CD19+ Raji cancer cell line expressing a red shifted luciferase reporter to track tumour progression by whole body luminescence. Although no therapeutic effect could be detected, the LentiSTIM treated groups resulted in higher survival when compared to the conventional CAR T cell and the negative control groups.

Download activity - last month

Export as CSVXMLJSON

Download activity - last 12 months

Export as CSVJSONXML

Downloads by country - last 12 months

Export as XMLJSONCSV

Archive Staff Only

View Item