In-vivo CAR – Speeding Up Immunotherapy

Chimeric antigen receptor T (CAR-T) immunotherapy achieved promising results in hematologic malignancies. However, one disadvantage of CAR-T treatment is cumbersome and expensive ex vivo manipulations that are time-consuming. Although allogeneic CAR-T cells partly solve this complexity, this process still requires vast manipulation and can cause graft-vs-host disease. The reprogramming of the CAR-T cells ex-vivo is mediated by a virus vector for example lentivirus (LV). The viral genome is replaced with a therapeutic gene cassette and the pathogenic traits are removed. Manipulation of the virus envelopes, also known as pseudo-virus, may gain some new characteristics to the vector. Therefore, we hypothesize that by creating a specifically targeted LV pseudotype virus toward T cells, we will be able to transduce CAR-T cells in vivo.

Research design starts with defining an LV pseudotype that specifically targets human T cells via specific T cell antigens. The examination of different lenti pseudo-virus constructs were carried out by delivering a GFP reporter gene into human T cells. The GFP expression was measured by flow cytometry. Then, we used the successful pseudotypes to create CAR-T by specific pseudoviruses and investigated the CAR-T cytotoxicity, in vitro by using ovarian cancer cell lines as the tumor model. Next, we will investigate the transduction efficiency and cytotoxicity of the pseudovirus in vivo. We expect that our method will provide an "off-the-shelf" product that significantly improves CAR-T availability to all patients around the world. In addition, using this method will allow a combination of several CAR-T treatments against various antigens.