Regulatable cell surface receptors and related compositions and methods

Inventors

MacKall, Crystal • LABANIEH, Louai • Majzner, Robbie • Lin, Michael Z.

Assignees

Leland Stanford Junior University

Abstract

Provided herein are cell surface receptors that include an extracellular binding domain, a transmembrane domain, an intracellular signaling domain, and a protease cleavage site disposed between the extracellular binding domain and the intracellular signaling domain. In certain aspects, the cell surface receptors are engineered cell surface receptors, such as chimeric antigen receptors (CARs). Also provided are cells that include such receptors (e.g., where the cells express the receptors on their surface) and pharmaceutical compositions including such cells. Nucleic acids that encode the cell surface receptors, cells including such nucleic acids, and pharmaceutical compositions including such cells, are also provided. Also provided are methods for regulating signaling of a cell surface receptor, and methods of using the cells of the present disclosure, including methods of using such cells to administer a regulatable cell-based therapy to an individual.

Core Innovation

The invention discloses signal neutralization by an inhibitable protease (SNIP) regulatable cell-surface receptors. A protease cleavage site is disposed between extracellular binding and intracellular signaling regions to neutralize signaling by protease cleavage, and protease activity is controlled by the presence or absence of a protease inhibitor, such that receptor signaling becomes regulatable rather than constitutive.

The disclosure provides receptor design options for implementing SNIP in chimeric antigen receptors (CARs) and engineered T cell receptors. These options include cleavage-site positioning, cis versus trans protease configurations, a membrane-tethered protease, and dimerization strategies to promote cleavage, with tuning of cleavage-site strength to adjust signaling output.

The document further ties the regulatable receptors to targeted binding of cancer antigens including B7-H3, GD2, HER2, CD19, and ROR1. Experimental evidence described in the disclosure supports drug-dependent control of CAR cleavage and signaling, with reduced leakiness/off-state activity and improved on/off kinetics compared with constitutive CARs.

The disclosure additionally reports altered exhaustion and memory phenotypes, tunable cytokine levels including IFNγ and IL-2, and reduced on-target off-tumor toxicity mediated by the regulatable design. It further describes improved survival in on-target/off-tumor toxicity models compared to constitutive CARs.

Claims Coverage

The independent claim coverage centers on a cell surface receptor with a protease cleavage site between the transmembrane domain and the intracellular signaling domain, with two main independent constraints relating to protease content and dimerization, and with the receptor limited to a CAR or an engineered TCR.

Across the provided coverage, the inventive structure remains a CAR or engineered TCR containing a protease cleavage site between the transmembrane and intracellular signaling domains, while excluding the protease and excluding a domain that dimerizes with the protease. Dependent refinements further specify antigen/cancer-cell surface binding and embodiments relating to engineered TCR, immune-cell types, and pharmaceutical compositions.

Stated Advantages

Documented Applications