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.

Provided are fusion proteins and related molecules useful for conducting base editing with reduced or no off-target mutations. The fusion proteins may include a first fragment comprising a nucleobase deaminase or a catalytic domain thereof, a second fragment comprising a nucleobase deaminase inhibitory domain, and a protease cleavage site between the first fragment and the second fragment. Also provided are improved prime editing systems, including prime editing guide RNA with improved stability.

Compounds having drug and bio-affecting properties, their pharmaceutical compositions and methods of use are set forth. In particular, betulinic acid derivatives that possess unique antiviral activity are provided as HIV maturation inhibitors, as represented by compounds of Formula I:

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These compounds are useful for the treatment of HIV and AIDS.

Compounds having drug and bio-affecting properties, their pharmaceutical compositions and methods of use are set forth. In particular, betulinic acid derivatives that possess unique antiviral activity are provided as HIV maturation inhibitors, as represented by compounds of Formula I: ##STR00001##
These compounds are useful for the treatment of HIV and AIDS.

Described herein are polypeptides, systems, and methods that relate to using domains that bind specifically to a biotinylamide to control receptor and cellular activity.

Some embodiments of the systems, methods and compositions provided herein relate to a compound protease. In some embodiments, the compound protease includes a protease domain and a cut site for another enzyme. In some embodiments, the compound protease includes an association domain. In some embodiments, the compound protease is part of a protein circuit.

Provided are fusion proteins and related molecules useful for conducting base editing with reduced or no off-target mutations. The fusion protein may include a first fragment comprising a nucleobase deaminase or a catalytic domain thereof, a second fragment comprising a nucleobase deaminase inhibitor, and a protease cleavage site between the first fragment and the second fragment. Also provided are improved prime editing systems, including prime editing guide RNA with improved stability.

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.

Disclosed herein include methods, compositions, and kits suitable for robust and tunable control of payload gene expression. Some embodiments provide rationally designed circuits, including miRNA-level and/or protein-level incoherent feed-forward loop circuits, that maintain the expression of a payload at an efficacious level. The circuit can comprise a promoter operably linked to a polynucleotide encoding a fusion protein comprising a payload protein, a protease, and one or more self-cleaving peptide sequences. The payload protein can comprise a degron and a cut site the protease is capable of cutting to expose the degron. The circuit can comprise a promoter operably linked to a polynucleotide comprising a payload gene, a silencer effector cassette, and one or more silencer effector binding sequences.