Publications by Lucia Baldi Unser

Related publications (54)

Reduction of adenovirus E1A mRNA by RNAi results in enhanced recombinant protein expression in transiently transfected HEK293 cells

Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Martin Bertschinger

Human embryonic kidney 293 (HEK293) cells, a widely used host for large-scale transient expression of recombinant proteins, are transformed with the adenovirus E1A and E1B genes. Because the E1A proteins function as transcriptional activators or repressors ...

2004

Transient gene expression in suspension HEK-293 cells: application to large-scale protein production

Florian Maria Wurm, Lucia Baldi Unser, Philippe Pierre Girard, Natalie Muller

Recent advances in genomics, proteomics, and structural biology raised the general need for significant amounts of pure recombinant protein (r-protein). Because of the difficulty in obtaining in some cases proper protein folding in bacteria, several method ...

2005

Role of non-specific DNA in reducing coding DNA requirement for transient gene expression with CHO and HEK-293E cells

Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Yashas Rajendra, Divor Kiseljak

Transient gene expression (TGE) is a rapid method for the production of recombinant proteins in mammalian cells. While the TGE volumetric productivity has improved significantly over the past decade, the amount of plasmid DNA (pDNA) needed for transfection ...

2012

The PiggyBac transposon enhances the frequency of CHO stable cell line generation and yields recombinant lines with superior productivity and stability

Florian Maria Wurm, David Hacker, Lucia Baldi Unser

Generating stable, high-producing mammalian cell lines is a major bottleneck in the manufacture of recombinant therapeutic proteins. Conventional gene transfer methods for cell line generation rely on random plasmid integration, resulting in unpredictable ...

Wiley-Blackwell2011

TubeSpin bioreactor 50 for the high-density cultivation of Sf-9 insect cells in suspension

Florian Maria Wurm, David Hacker, Lucia Baldi Unser

Here we present the TubeSpin bioreactor 50 (TubeSpins) as a simple and disposable culture system for Sf-9 insect cells in suspension. Sf-9 cells had substantially better growth in TubeSpins than in spinner flasks. After inoculation with 106 cells/ml, maxim ...

Springer Netherlands2011

Comparative Study on the In Vitro Cytotoxicity of Linear, Dendritic, and Hyperbranched Polylysine Analogues

Harm-Anton Klok, Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Zuzana Kadlecova

Lysine-based polycations are widely used as nonviral carriers for gene delivery. This manuscript reports the results of a comparative study on the in vitro cytotoxicity of a library of three structural polylysine variants, namely, linear polylysine (LPL), ...

American Chemical Society2012

Arginine-Based Biodegradable Ether–Ester Polymers with Low Cytotoxicity as Potential Gene Carriers

Jutta Christine Wandrey, Lucia Baldi Unser

The success of gene therapy depends on safe and effective gene carriers. Despite being widely used, synthetic vectors based on poly(ethylenimine) (PEI), poly(l-lysine) (PLL), or poly(l-arginine) (poly-Arg) are not yet fully satisfactory. Thus, both improve ...

American Chemical Society2014

Rapid recombinant protein production from piggyBac transposon-mediated stable CHO cell pools

Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Zuzana Kadlecova, Sowmya Balasubramanian

Heterogeneous populations of stably transfected cells (cell pools) can serve for the rapid production of moderate amounts of recombinant proteins. Here, we propose the use of the piggyBac (PB) transposon system to improve the productivity and long-term sta ...

Elsevier2015

Poly(ethyleneimine)-Mediated Large-Scale Transient Gene Expression: Influence of Molecular Weight, Polydispersity and N-Propionyl Groups

Harm-Anton Klok, Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Zuzana Kadlecova

Three synthesis lots of linear poly(ethyleneimine) (PEI) are compared to a fully hydrolyzed linear PEI (commercially available as PEI Max) regarding structure, polyplex formation with plasmid DNA, and transfection of suspension-adapted HEK-293E cells. PEI ...

Wiley-Blackwell2012

Comparison of Three Transposons for the Generation of Highly Productive Recombinant CHO Cell Pools and Cell Lines

Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Yashas Rajendra, Sowmya Balasubramanian

Several naturally occurring vertebrate transposable elements have been genetically modified to enable the transposition of recombinant genes in mammalian cells. We compared three transposonspiggyBac, Tol2, and Sleeping Beautyfor their ability to generate c ...

Wiley-Blackwell2016

Transcriptional and post-transcriptional limitations of high-yielding, PEI-mediated transient transfection with CHO and HEK-293E cells

Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Yashas Rajendra, Divor Kiseljak

Transient gene expression (TGE) in human embryonic kidney (HEK-293) and Chinese hamster ovary (CHO) cells is a well-established technology for the rapid generation of recombinant proteins. Although the maximum TGE yields have reached 1 g/L or more, the amo ...

American Chemical Society2015

Enhanced Plasmid DNA Utilization in Transiently Transfected CHO-DG44 Cells in the Presence of Polar Solvents

Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Yashas Rajendra, Divor Kiseljak, Sowmya Balasubramanian

Although the protein yields from transient gene expression (TGE) with Chinese hamster ovary (CHO) cells have recently improved, the amount of plasmid DNA (pDNA) needed for transfection remains relatively high. We describe a strategy to reduce the pDNA amou ...

American Chemical Society2015

Sustained activation and tumor targeting of NKT cells using a CD1d-anti-HER2-scFv fusion protein induce antitumor effects in mice

Florian Maria Wurm, Lucia Baldi Unser

Invariant NKT (iNKT) cells are potent activators of DCs, NK cells, and T cells, and their antitumor activity has been well demonstrated. A single injection of the high-affinity CD1d ligand α-galactosylceramide (αGalCer) leads to short-lived iNKT cell activ ...

2008

Virus-free transient protein production in Sf9 cells

Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Xiao Shen

A method for virus-free transient gene expression from suspension-adapted Sf9 insect cells was developed with the gene of interest being expressed from a plasmid carrying the homologous region 5 enhancer (hr5) and the immediate early 1 (ie1) promoter from ...

Elsevier2014

Cell Compatible Arginine Containing Cationic Polymer: One-Pot Synthesis and Preliminary Biological Assessment

Jutta Christine Wandrey, Lucia Baldi Unser, Xiao Shen

Synthetic cationic polymers are of interest as both nonviral vectors for intracellular gene delivery and antimicrobial agents. For both applications synthetic polymers containing guanidine groups are of special interest since such kind of organic compounds ...

Springer India2014

DNA delivery with hyperbranched polylysine: A comparative study with linear and dendritic polylysine

Harm-Anton Klok, Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Yashas Rajendra, Zuzana Kadlecova

PEI and polylysine are among the most investigated synthetic polymeric carriers for DNA delivery. Apart from their practical use, these 2 classes of polymers are also of interest from a fundamental point of view as they both can be prepared in different ar ...

Elsevier2013

Disposable 600-mL orbitally shaken bioreactor for mammalian cell cultivation in suspension

Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Dominique Terry Monteil Jr, Saroj Ghimire

Orbitally shaken bioreactors (OSRs) support the efficient cultivation of mammalian cells in suspension at various scales of operation. Here we introduce a disposable culture vessel with a ventilated cap having a nominal volume of 600 mL (TubeSpin (R) biore ...

Elsevier2013

Recombinant therapeutic protein production in cultivated mammalian cells: current status and future prospects

Florian Maria Wurm, David Hacker, Lucia Baldi Unser

Recombinant therapeutic proteins produced in mammalian cells represent a major class of biopharmaceuticals. In recent years, their demand has increased dramatically and is now driving the development of a variety of improvements to maximize their expressio ...

Elsevier2008

A simple high-yielding process for transient gene expression in CHO cells

Florian Maria Wurm, David Hacker, Lucia Baldi Unser, Yashas Rajendra, Divor Kiseljak

Here we describe a simplified method for transient gene expression (TGE) in suspension-adapted Chinese hamster ovary (CHO) cells using polyethylenimine (PEI) for DNA delivery. Both the transfection and production phases of the bioprocess were performed at ...

Elsevier2011

Hyperosmolarity enhances transient recombinant protein yield in Chinese hamster ovary cells

Florian Maria Wurm, David Hacker, Lucia Baldi Unser

The effect of hyperosmolarity on transient recombinant protein production in Chinese hamster ovary (CHO) cells was investigated. Addition of 90 mM NaCl to the production medium ProCHO5 increased the volumetric yield of recombinant antibody up to 4-fold rel ...

Springer Netherlands2010