The goal of this application is to determine if lentiviral-engineered T cells, that express either an HLA-A2 or an HLA-23,24 restricted T cell receptor (TCR) specific for the EBV latency antigen LMP-2, are capable of recognizing this antigen as expressed by EBV transformed primary B lymphocytes (B-LCL) to a cytolytic effect. In producing and evaluating these vectors we will generate a unique set of gene therapy vectors for EBV- associated disease, determine which peripheral blood subsets serve as the optimal target for transduction and also determine whether transduced T cells are subject to the same immune controls as non-transduced T cells. Documenting the normal immunobiology of lentiviral transduced T cells will enhance the confidence already being gained from clinical use of these vectors in phase I trials for HIV patients. Epstein Barr virus (EBV)-associated diseases that are medically significant and thought to be amenable to immune control include AIDS-associated lymphoma, Hodgkin lymphoma, post-transplant lymphoma, and nasopharyngeal carcinoma. Each of these EBV-associated malignancies expresses the EBV-encoded latency membrane protein-2 (LMP-2). Lentigen's collaborator, Dr. Rimas Orentas, has helped pioneer the used of adoptive immunotherapy to treat EBV-associated malignancy.
In Aim 1 we will develop self-inactivating (SIN) lentiviral vectors that express TCRs cloned by the Orentas lab, that target an HLA-A2-restricted (residues 131-139) or HLA-23,24-restricted (residues 425-433) epitope of LMP-2. In previous work the Orentas lab demonstrated the ability of these TCRs to be functionally expressed in primary human T cells using a retroviral vector. Importantly, this was the first report to demonstrate the ability to lyse B-LCL (a target cell of high biological relevance as opposed to peptide- pulsed targets or targets engineered to express LMP-2). However, the retroviral vector was suboptimal and production of high-titer stock difficult on even a laboratory scale. Using the research and development capability of Lentigen, we propose here to generate new vectors, using a state-of-the-art lentiviral system, that will place in the hands of the clinical and research community effective tools to treat EBV-associated malignancy. Over the last few years the use of TCRs to treat disease has gone from a speculative research topic to concrete clinical protocols. We propose to do the same with our cloned LMP-2 specific TCRs. Our ultimate goal is to provide an immunotherapeutic options to patients suffering from EBV-associated malignancy. ? ?
