Photoconjugation reactions for modification of specific proteins on live cells
US12018081B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 2020 |
| Grant date | Jun 25, 2024 |
| Priority date | — |
| Expiry date | Jul 26, 2041 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC12Y305/04001
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
A prodrug enzyme covalently photoconjugated to a live cell receptor survives endosomal proteolysis and retains its catalytic activity on the living cell membrane over multiple days. Antibody-directed enzyme prodrug therapy is a promising approach for selective treatment of solid tumors, but methods are needed to preserve enzyme activity on living cell membranes over multiple prodrug dosings. A fusion protein was designed with both an anti-epidermal growth factor receptor (EGFR) affibody and the prodrug enzyme cytosine deaminase, which can convert prodrug 5-fluorocytosine to the anticancer drug 5-fluorouracil. A benzophenone group was added at a site-specific mutation within the affibody portion, and the fusion protein was selectively and irreversibly photoconjugated to EGFR receptors expressed on membranes of live MDA-MB-468 breast cancer cells. Affinity-mediated covalent conjugation of the affibody-enzymes to cell receptors allows for prolonged expression on membranes and retained enzymatic activity without genetic engineering.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.