Reported herein is a sortase comprising an amino acid sequence that is at least 90% identical to the amino acid sequence of SEQ ID NO: 11 and that comprises the mutations D101S and K137S.

The invention relates to benzodiazepine derivatives with antiproliferative activity and more specifically to benzodiazepine compounds of formulae (I), (II), (TI) and (T2). The invention also provides conjugates of the benzodiazepine compounds linked to a cell-binding agent. The invention further provides compositions and methods for inhibiting abnormal cell growth or treating a proliferative disorder in a mammal using the compounds or conjugates of the invention.

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The invention relates to benzodiazepine derivatives with antiproliferative activity and more specifically to benzodiazepine compounds of formulae (I), (II), (TI) and (T2). The invention also provides conjugates of the benzodiazepine compounds linked to a cell-binding agent. The invention further provides compositions and methods for inhibiting abnormal cell growth or treating a proliferative disorder in a mammal using the compounds or conjugates of the invention.

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The invention provides novel peptides (e.g., linkers) and polypeptide compositions comprising the linkers (e.g., fusion proteins) and methods of using the polypeptide compositions. Peptides (e.g., linkers) are useful as tags and for engineering fusion proteins (e.g., antigen binding molecules, scFv). Polypeptide linkers described herein facilitate flexibility of linked peptides allowing for proper folding, conformation and reduced immunogenicity.

The invention provides novel peptides (e.g., linkers) and polypeptide compositions comprising the linkers (e.g., fusion proteins) and methods of using the polypeptide compositions. Peptides (e.g., linkers) are useful as tags and for engineering fusion proteins (e.g., antigen binding molecules, scFv). Polypeptide linkers described herein facilitate flexibility of linked peptides allowing for proper folding, conformation and reduced immunogenicity.

The present invention relates to the technical field of medicines, and relates to a polyethylene glycol conjugated drug, a preparation method therefor and the use thereof. In particular, the present invention relates to a polyethylene glycol conjugated drug as shown in formula I or a pharmaceutically acceptable salt thereof. The present invention also relates to a method for preparing the polyethylene glycol conjugated drug or the pharmaceutically acceptable salt thereof, a pharmaceutical composition comprising the polyethylene glycol conjugated drug or the pharmaceutically acceptable salt thereof, and the use thereof in the preparation of a drug.

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The present invention relates to an antibody-drug conjugate comprising an exosome secretion inhibitor conjugated to an antibody for inhibiting immune checkpoints, and the use thereof for treating cancer. An antibody-drug conjugate according to the present invention is maintained, in normal tissue, in a form in which a drug is conjugated to an antibody, and releases the drug upon reaching a cancer microenvironment, thereby inhibiting the secretion of cancer exosomes that cause an immunosuppressive mechanism. Thus the antibody-drug conjugate exhibits high therapeutic efficacy and can remarkably increase the objective response rate to an immune checkpoint inhibitor.

The present invention relates to an antibody-drug conjugate comprising an exosome secretion inhibitor conjugated to an antibody for inhibiting immune checkpoints, and the use thereof for treating cancer. An antibody-drug conjugate according to the present invention is maintained, in normal tissue, in a form in which a drug is conjugated to an antibody, and releases the drug upon reaching a cancer microenvironment, thereby inhibiting the secretion of cancer exosomes that cause an immunosuppressive mechanism. Thus the antibody-drug conjugate exhibits high therapeutic efficacy and can remarkably increase the objective response rate to an immune checkpoint inhibitor.

Provided herein are antibodies comprising acceptor glutamine sequences at site-specific positions, compositions comprising the antibodies, conjugates of the antibodies, methods of their production, and methods of their use. The antibodies are useful for methods of treatment and prevention, methods of detection and methods of diagnosis.

Provided herein are antibodies comprising acceptor glutamine sequences at site-specific positions, compositions comprising the antibodies, conjugates of the antibodies, methods of their production, and methods of their use. The antibodies are useful for methods of treatment and prevention, methods of detection and methods of diagnosis.