US 5122464

Patent Overview — US5122464A

Title: Method for dominant selection in eucaryotic cells

Patent number: US5122464A | Application number: US07/595,733 | Filed: 1987-01-23 | Priority date: 1986-01-23 | Granted/Published: 1992-06-16

Current assignees (as listed, accuracy not represented): University of Glasgow; Celltech R&D Ltd. Original assignees: University of Glasgow; Celltech Ltd. Inventors: Richard H. Wilson; Christopher R. Bebbington. Legal status: Expired – Lifetime; anticipated expiration 2009-06-16.

Purpose: The patent concerns selecting genetically transformed eucaryotic (mammalian) host cells. Its stated subject matter centers on glutamine synthetase (GS) as a selectable marker, expression vectors encoding it, and methods of transforming and culturing cells. The abstract is indexed to glutamine and the claims/description to glutamine synthetase, methionine, methionine sulfoximine, and phosphinothricin-type inhibitors.

Plain-language scope: Rather than relying on a drug-resistance marker, the disclosed approach uses a gene encoding glutamine synthetase introduced into a eucaryotic host cell. Cells taking up and expressing the recombinant DNA can be distinguished (dominantly selected) from non-transformed cells, for example by growth conditions or by exposure to an inhibitor of glutamine synthetase such as methionine sulfoximine. The patent text also addresses recombinant DNA, vectors, transcription/regulatory effects, and amplification, and mentions proteins of interest including tissue plasminogen activator (tPA) and DHFR in the description. The claims also refer to culturing methods, consistent with use of the selected cells to produce desired protein products.

Source: https://patents.google.com/patent/[US5122464](/patent/US5122464)/en

What the excerpt does not establish: It does not provide the full claim language or claim count, a complete specification, exact experimental examples or cell lines, precise vector constructs, or specific sequences. It lists a litigation link and a security-agreement reassignment entry, but provides no litigation substance or ownership analysis; none is assessed here. Expanded-family details, foreign counterparts, and legal effect are likewise not established by this excerpt.