Abstract: Aspects of the invention are drawn to compositions and methods for treating and preventing autoimmune disease.

Abstract: Provided herein are methods for producing site specific PEG modifications to single domain antibodies (e.g., VHHs). Methods for producing site-specifically conjugated bivalent single domain antibodies (e.g., VHHs) are also provided. Methods for labeling (e.g., with a fluorophore or radionuclide) site-specifically PEGylated single domain antibodies and site-specifically conjugated bivalent single domain antibodies are also provided.

Abstract: Provided herein are methods for producing site specific PEG modifications to single domain antibodies (e.g., VHHs). Methods for producing site-specifically conjugated bivalent single domain antibodies (e.g., VHHs) are also provided. Methods for labeling (e.g., with a fluorophore or radionuclide) site-specifically PEGylated single domain antibodies and site-specifically conjugated bivalent single domain antibodies are also provided.

Abstract: The present invention, in some aspects, provides methods, reagents, compositions, and kits for the radiolabeling of proteins, for example, of proteins useful for positron emission tomography (PET) or single-photon emission computed tomography (SPECT) (e.g., for diagnostic and therapeutic applications), using sortase-mediated transpeptidation reactions. Some aspects of this invention provide methods for the conjugation of an agent, for example, a radioactive agent or molecule to diagnostic or therapeutic peptides or proteins. Compositions comprising sortagged, radiolabeled proteins as well as reagents for generating radiolabeled proteins are also provided. Kits comprising reagents useful for the generation of radiolabeled proteins are provided, as are precursor proteins that comprise a sortase recognition motif.

Abstract: MHC multimers are provided in which peptide-loaded MHC monomers are covalently linked to a multimerization domain through conjugation moieties on the monomers and the multimerization domain. The multimers can further comprise oligonucleotide barcodes. Peptide exchange can be performed with a plurality of pMHC multimers to create pMHC multimer libraries. Methods of making and using the pMHC multimers and libraries are also provided. Peptide-loaded MHC Class I and MHC Class II multimers, and libraries thereof, are provided.

Abstract: The present invention, in some aspects, provides methods, reagents, compositions, and kits for the radiolabeling of proteins, for example, of proteins useful for positron emission tomography (PET) or single-photon emission computed tomography (SPECT) (e.g., for diagnostic and therapeutic applications), using sortase-mediated transpeptidation reactions. Some aspects of this invention provide methods for the conjugation of an agent, for example, a radioactive agent or molecule to diagnostic or therapeutic peptides or proteins. Compositions comprising sortagged, radiolabeled proteins as well as reagents for generating radiolabeled proteins are also provided. Kits comprising reagents useful for the generation of radiolabeled proteins are provided, as are precursor proteins that comprise a sortase recognition motif.

Abstract: The present invention, in some aspects, provides methods, reagents, compositions, and kits for the radiolabeling of proteins, for example, of proteins useful for positron emission tomography (PET) or single-photon emission computed tomography (SPECT) (e.g., for diagnostic and therapeutic applications), using sortase-mediated transpeptidation reactions. Some aspects of this invention provide methods for the conjugation of an agent, for example, a radioactive agent or molecule to diagnostic or therapeutic peptides or proteins. Compositions comprising sortagged, radiolabeled proteins as well as reagents for generating radiolalebed proteins are also provided. Kits comprising reagents useful for the generation of radiolabeled proteins are provided, as are precursor proteins that comprise a sortase recognition motif.

Abstract: Provided herein are methods for producing site specific PEG modifications to single domain antibodies (e.g., VHHs). Methods for producing site-specific ally conjugated bivalent single domain antibodies (e.g., VHHs) are also provided. Methods for labeling (e.g., with a fluorophore or radionuclide) site-specifically PEGylated single domain antibodies and site-specifically conjugated bivalent single domain antibodies are also provided.

Abstract: The present invention relates to triorthogonal reagents useful for site-specifically modifying a protein with two orthogonal groups that can be subsequently functionalized in a single one-pot procedure. This approach relies on the selective tagging of proteins containing an appended farnesyltransferase or geranylgeranyltransferase I substrate sequence. The incorporation of a bifunctional ethynyl-hydroxybenzaldehyde into the farnesyl or geranylgeranyl group facilitates the facile labeling of proteins with two different moieties.

Abstract: The present invention, in some aspects, provides methods, reagents, compositions, and kits for the radiolabeling of proteins, for example, of proteins useful for positron emission tomography (PET) or single-photon emission computed tomography (SPECT) (e.g., for diagnostic and therapeutic applications), using sortase-mediated transpeptidation reactions. Some aspects of this invention provide methods for the conjugation of an agent, for example, a radioactive agent or molecule to diagnostic or therapeutic peptides or proteins. Compositions comprising sortagged, radiolabeled proteins as well as reagents for generating radiolalebed proteins are also provided. Kits comprising reagents useful for the generation of radiolabeled proteins are provided, as are precursor proteins that comprise a sortase recognition motif.

Abstract: The present invention relates to triorthogonal reagents useful for site-specifically modifying a protein with two orthogonal groups that can be subsequently functionalized in a single one-pot procedure. This approach relies on the selective tagging of proteins containing an appended farnesyltransferase or geranylgeranyltransferase I substrate sequence. The incorporation of a bifunctional ethynyl-hydroxybenzaldehyde into the farnesyl or geranylgeranyl group facilitates the facile labeling of proteins with two different moieties.