Altering Gene Expression in CART Cells and Uses Thereof

Abstract

The present invention relates to compositions and methods for generating a modified T cell with a nucleic acid capable of downregulating endogenous gene expression selected from the group consisting of TCR α chain, TCR β chain, beta-2 microglobulin, a HLA molecule, CTLA-4, PD1, and FAS and further comprising a nucleic acid encoding a modified T cell receptor (TCR) comprising affinity for a surface antigen on a target cell or an electroporated nucleic acid encoding a chimeric antigen receptor (CAR). Also included are methods and pharmaceutical compositions comprising the modified T cell for adoptive therapy and treating a condition, such as an autoimmune disease.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]The present application is entitled to priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 62 / 073,651, filed Oct. 31, 2014, which is hereby incorporated by reference in its entirety herein.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]This invention was made with government support under CA120409 awarded by the National Institute of Health. The government has certain rights in the invention.BACKGROUND OF THE INVENTION[0003]Adoptive cell transfer (ACT) using chimeric antigen receptor (CAR) modified T cells has been shown to be a promising strategy for the treatment of cancers (Louis et al., 2011, Blood 118:6050-6056; Kochenderfer et al., 2010, Blood 116:3875-3886 and Porter et al., 2011, N Engl J Med 365:725-733).[0004]Integration associated safety concerns using lentiviral or retroviral vectors are a major concern for modification of cells used for ACT. Some advances have been made to avoid on...

AI Technical Summary

Benefits of technology

[0322]One advantage of RNA transfection methods of the invention is that RNA transfection is essentially transient and a vector-free. A RNA transgene can be delivered to a lymphocyte and expressed therein following a brief in vitro cell activation, as a minimal expressing cassette without the need for any additional viral sequences. Under these conditions, integration of the transgene into the host cell genome is unlikely. Cloning of cells is not necessary because of the efficiency of transfection of the RNA and its ability to uniformly modify the entire lymphocyte population.

Problems solved by technology

However, the major constraint for transient expression of CARs is the suboptimal effector activity and functionality of RNA transfected T cells.

Unfortunately, these constructs were severely limited in functionality because of a short half-life, poor accessibility to target cell sites, and a lack of proper long term signaling function.

Clinical TCR studies have been hampered by low expression levels of the transduced TCR, as well as mispairing of α and β chains.

Because four TCRs can potentially be expressed at the cell surface when a T cell transcribes the chains of two different TCRs (native alpha / beta, exogenous alpha / beta, and native / exogenous “mispaired” heterodimers), significant obstacles to the use of this approach are evident.

In studies performed to date, preclinical studies have clearly demonstrated that TCR miss-pairings have the potential to induce harmful recognition of self-antigens.

Although early TCR and CAR T cell clinical data obtained in treating cancers has shown promising results, the risk to the patient is high, and some patients' T cells are not potent enough for effective treatment even after TCR or CAR redirection, forcing modification of allogeneic donor-derived T cells.

This approach has achieved early clinical successes but is limited by the time and expense to manufacture patient-specific T-cell products.

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