The present disclosure provides inducible cell receptors and therapeutic cells comprising the inducible cell receptors. Further provided are methods of preparing the therapeutic cells and methods of treating a subject by administering the therapeutic cells and regulating activity of (e.g. activating and/or inactivating) the cell receptors.

Provided are polypeptides that include, from N-terminus to C-terminus, a chimeric antigen receptor (CAR), a protease, and a degron, where the polypeptide further includes a cleavage site for the protease disposed between the CAR and the degron. Also provided are cells that include such polypeptides (e.g., where the cells express the CAR on their surface) and pharmaceutical compositions including such cells. Nucleic acids that encode the polypeptides, cells including such nucleic acids, and pharmaceutical compositions including such cells, are also provided. Also provided are methods for controlling the expression of a CAR on the surface of a cell, and methods of using the cells of the present disclosure, including methods of using such cells to administer a regulatable CAR cell-based therapy (e.g., a regulatable CAR T cell therapy) to an individual.

Provided herein are compositions and methods for inducing protein function. For example, in some embodiments, provided herein are compositions and methods for pharmacological induction of protein function.

The technology described herein is directed to CAR polypeptides and systems comprising repressible proteases. In combination with a specific protease inhibitor, the activity of said CAR polypeptides and systems and cells comprising them can be modulated. Also described herein are methods of using said CAR polypeptides and systems, for example to treat various diseases and disorders.

The technology described herein is directed to CAR polypeptides and systems comprising repressible proteases. In combination with a specific protease inhibitor, the activity of said CAR polypeptides and systems and cells comprising them can be modulated. Also described herein are methods of using said CAR polypeptides and systems, for example to treat various diseases and disorders.

Engineered fusion proteins comprising a self-excising degron for controlling protein production are disclosed. In particular, the inventors have constructed fusion proteins comprising a degron connected to a protein of interest through a cleavable linker comprising a hepatitis C virus (HCV) protease site. The degron can be removed from the protein of interest by a cis-encoded HCV protease such that the protein of interest can be produced with minimal structural modification. Clinically available HCV protease inhibitors can be used to block protease cleavage such that the degron is retained after inhibitor addition on subsequently synthesized protein copies. The degron when attached causes rapid degradation of the linked protein. Such fusions of a degron to a protein of interest will be especially useful when control over protein production with minimal structural modification is desired.

Disclosed herein include methods, compositions, and systems suitable for use in delivering a polynucleotide to a target cell of a subject in need thereof. In some embodiments, a viral vector comprises a polynucleotide encoding nucleoprotein (N), phosphoprotein (P), matrix protein (M), RNA-dependent RNA polymerase (L), and one or more transgenes. The viral vector can comprise one or more of a conditionally stable fusion protein, a protease fusion protein, a degron fusion protein, and/or a glycoprotein derived of another species than the viral vector polynucleotide to enable control of viral vector transduction and/or replication.

Engineered fusion proteins comprising a self-excising degron for controlling protein production are disclosed. In particular, the inventors have constructed fusion proteins comprising a degron connected to a protein of interest through a cleavable linker comprising a hepatitis C virus (HCV) protease site. The degron can be removed from the protein of interest by a czs-encoded HCV protease such that the protein of interest can be produced with minimal structural modification. Clinically available HCV protease inhibitors can be used to block protease cleavage such that the degron is retained after inhibitor addition on subsequently synthesized protein copies. The degron when attached causes rapid degradation of the linked protein. Such fusions of a degron to a protein of interest will be especially useful when control over protein production with minimal structural modification is desired.

Compositions and methods for targeted treatment of cancer are disclosed. In particular, the invention relates to methods of targeting anti-cancer therapy to cells exhibiting aberrant signaling associated with cancer pathogenesis by administering synthetic signaling proteins that couple detection of an oncogenic signal to release of therapeutic agents into cancerous cells.

Disclosed herein include methods, compositions, and systems suitable for use in delivering a polynucleotide to a target cell of a subject in need thereof. In some embodiments, a viral vector comprises a polynucleotide encoding nucleoprotein (N), phosphoprotein (P), matrix protein (M), RNA-dependent RNA polymerase (L), and one or more transgenes. The viral vector can comprise one or more of a conditionally stable fusion protein, a protease fusion protein, a degron fusion protein, and/or a glycoprotein derived of another species than the viral vector polynucleotide to enable control of viral vector transduction and/or replication.