Mutated piggyBac Transposase Engineered Variants for More Stable Cells and Higher Recombinant Protein Yield

This patent describes engineered variants of the piggyBac transposase enzyme that have been mutated to increase stability inside the host cell. The variants are presented as tools for stable transfection, cell line development, genome modification and improving the titer of recombinant proteins in biomanufacturing.

The Problem

PiggyBac is one of the most widely used transposon systems in mammalian cell engineering. The transposase enzyme cuts the piggyBac transposon out of one location and pastes it into another, allowing genes of interest to be integrated efficiently into a host cell genome. For Chinese hamster ovary and other production cell lines, this gives manufacturers a fast route from sequence to high-producing pool. The catch is that the wild-type transposase is not very stable in the cell, which limits its activity and reproducibility. In a biologics development environment, where every fold of improvement in product titer translates to lower cost of goods, getting more out of the transposase has real economic value.

What This Invention Does

The patent describes piggyBac transposases that have been engineered with specific mutations to increase their intracellular stability. The engineered enzymes are useful for stably transforming cells, for cell line development, for genome modification, and for improving titers of recombinant protein products. The disclosure covers the mutated transposase sequences themselves, the nucleic acids encoding them, methods of using them to integrate genes of interest, and the cells and cell lines produced.

By extending the working life of the enzyme inside the cell, the variants are intended to make integration more efficient and the resulting cell lines more reliable.

Key Features

• Stability-enhancing mutations. Specific changes to the transposase amino acid sequence that increase the enzyme’s intracellular half-life.
• Broad utility. Useful across stable transfection, cell line development, genome modification and recombinant protein production.
• Higher recombinant protein titer. Improved integration efficiency translates to higher expression and product yield in production cell lines.
• Cell-line agnostic. The mutated enzyme can be applied across mammalian production hosts, including CHO and related lines used for biologics.
• Composition and method coverage. The patent claims both the mutated enzymes and the methods of using them, giving Amgen reach across the value chain.

Who Is Behind It

The applicant is Amgen Inc., one of the world’s largest biotechnology companies and a leading producer of therapeutic monoclonal antibodies and other recombinant protein therapies. The named inventors are Noelia Blanco Talavan, Huong Thi Ngoc Le, Jennitte L. Stevens, Kristine M. Daris and Neeraj J. Agrawal, consistent with a cell line and process development group at the company. The Australian application is a divisional of AU 2019398101 and traces back to PCT/US2019/065129 with priority to US 62/777,325 and US 62/925,516. The Australian patent attorney of record is listed on the title page.

Why It Matters

Cell line development is one of the foundational steps in biologics manufacturing and is increasingly a competitive front in the industry. Australia is investing in domestic biologics capacity, and any cell engineering platform that improves titer or speeds development is of direct relevance to local contract manufacturers and to Amgen’s own operations. The piggyBac platform itself is widely licensed, so improvements to the underlying enzyme have value not only as captive tools but as licensable assets within the broader synthetic biology ecosystem.

Related Concepts

• piggyBac transposon system – the gene-delivery platform the enzyme drives.
• Transposase – the enzyme class being engineered.
• Cell line development – the workflow in which improved transposase reduces time and cost.
• Chinese hamster ovary cells – the dominant production host in biologics manufacturing.
• Recombinant DNA – the foundational technology underlying these workflows.

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AU 2026201887 was published in the Australian Official Journal of Patents on 2 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.