The present invention provides a method of targeted molecular imaging and/or targeted drug delivery, wherein two components or probes each interacts with one or more biomarkers on a cell and separately interact with each other to form a stable bond, such as a stable covalent bond. In certain non-limiting embodiments, at least one of the probes is photo-triggered to allow for bonding with at least one second probe. In certain non-limiting embodiments, the cell is a tumor or cancer cell. The present invention also relates to compounds, probes, and kits for use in targeted molecular imaging and/or targeted drug delivery.

The present invention concerns materials and method for delivery and internalization of an agent into a cell even in the presence of an immune response, such as antibodies or antisera or immune cells that bind to the agent. The agent can be a compound, drug, peptide, protein, nucleic acid, antigen, immunogen, or other biological molecule. In one embodiment, the agent is operatively linked to a lectin-based carrier. The present invention can be used for delivery and cellular internalization of any entity where an immune response to the entity is present or is likely to be produced or developed. The present invention also concerns methods and materials for providing for an adjuvant and carrier for vaccinations of a person or animal. The present invention also concerns a method for treating or preventing a disease or condition in a human or animal wherein the human or animal has produced or will produce an immune response against a therapeutic agent that can treat said disease or condition, the method comprising administering to the human or animal an effective amount of said therapeutic agent operatively linked to a lectin-based carrier.

The present invention provides a multivalent compound for targeted molecular imaging and/or targeted drug delivery, wherein two components or targeting molecules each interacts with one or more biomarkers on a cell. The present invention further provides a multifunctional chelator to combine the targeting molecules. The present invention also provides an in vitro high-throughput screening assay to determine the length of the spacer molecules. The present invention also relates to compounds/probes, kits and methods for use in targeted molecular imaging and/or targeted drug delivery.

Described herein are compositions of extracellular vesicles, and methods and systems of producing the extracellular vesicles. Also described herein are methods of using the extracellular vesicles.

The present invention provides a method of targeted molecular imaging and/or targeted drug delivery, wherein two components or probes each interacts with one or more biomarkers on a cell and separately interact with each other to form a stable bond, such as a stable covalent bond. In certain non-limiting embodiments, at least one of the probes is photo-triggered to allow for bonding with at least one second probe. In certain non-limiting embodiments, the cell is a tumor or cancer cell. The present invention also relates to compounds, probes, and kits for use in targeted molecular imaging and/or targeted drug delivery.

Herein is reported a conjugate of a haptenylated polypeptide toxin and an anti-hapten antibody, wherein a disulfide bond is formed between a cysteine residue either before or after the lysine residue that is used for hapten-conjugation and a cysteine residue in the CDR2 of the antibody, whereby the CDR2 is determined according to Kabat.