CHO Cell Line Development Services
A high-performing cell line is fundamental to establishing a robust protein production process. However, tight timelines, pressure to achieve first-in-class status, limited resources, and growing molecule complexity make it increasingly risky to rely on trial-and-error approaches.
Sartorius CHO cell line development services combines an engineered CHO host cell line, data‑driven workflows, and experienced scientists to help you make confident decisions from DNA to IND. Whether you are a small start‑up or a large biotech, we tailor the program to your molecule, your risk profile, and your internal setup — from fully outsourced cell line development services to in‑house licensing of technology that enables your own team to run the platform.
Our service is built on a strong foundation of expert knowledge and cutting-edge technology. In 2025, we celebrated 10 years since integrating Cellca—industry-leading specialists in the development of cell lines—into the Sartorius family, and 20 years since Cellca was founded. This legacy of innovation and expertise enables us to provide effective solutions tailored to your challenges.
With flexibility at its core, our service takes a truly biotech-first approach. Whether you have no in-house capabilities or just need help with some elements of the cell line development workflow, our dedicated team cooperates with you to carve a reliable and streamlined path to IND readiness.
Novel Genetically Engineered CHO Host
See how our rationally designed, genetically engineered CHO host improves productivity and stability, ensuring greater certainty in your cell line development project.
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A Reliable Pathway to IND-Ready Material
When timelines are tight and molecules are complex, it is crucial to partner with a trusted cell line development expert known for predictable outcomes and with a proven track record.
Our CHO cell line development platform combines an engineered host cell line, optimized expression tools, a tailored media system, data-rich prediction and screening tools, and robust scale‑down models to create a reliable pathway from DNA to IND‑ready material. This continuously evolving platform drives the high performance you can expect today, with its impact reflected in the consistent track record our team has built across diverse programs.
Speed and Quality Through A Data-Driven Process
A trusted cell line development partner should consistently deliver high‑yielding, stable cell lines with optimal product quality. We achieve this through a data-driven process led by experienced scientists and enabled by advanced technologies, ensuring that each decision is based on robust evidence. This approach allows us to accelerate your program without compromising quality, ensuring the confident selection of the optimal cell line and establishing a strong foundation for your future drug development journey.
- Exceptionally high titers and productivities, even prior to process optimization
- Capabilities across diverse molecule types including classical monoclonal antibodies (mAbs) and more complex proteins
- Automation, high‑throughput screening tools, and AI | ML predictive modeling to support data‑driven decision-making.
- Rapid delivery timelines, with research cell banks (RCB) provided within 9 weeks and master cell bank (MCB) manufacturing and release completed in 9 months.
Learn how we have significantly reduced CLD timelines by using advanced platform technologies to deliver high-producing clones. Read Article
Parvus Therapeutics, USA
The cell line titer is well above our target. We are very pleased with Sartorius’ performance, working with Parvus to deliver a highly productive clone.
Over 330 Projects Completed
Take advantage of our diverse collective experience to avoid costly mistakes when navigating the complex process of cell line development.
- Our reliable history includes over 15 years of experience and more than 330 successfully completed cell line development projects
- 85+ molecules are currently in clinical stages, with 10 approved for market use
- Our clients frequently return for further collaborations, with some having partnered with us on more than 15 projects
Biotech Customer (California, USA)
We are very satisfied with the outcome of the project. The initial timeline was precisely met and the titer was better than expected for a very difficult molecule. The team at Sartorius was also responsive, capable, and easy to work with.
Key Elements of Our CHO Cell Line Development Platform
Our platform is built as an integrated system: an engineered CHO host cell line, optimized expression vectors, 4Cell® SmartCHO media, advanced screening and modeling tools, and scalable bioprocess design. Together with the broader Sartorius technology ecosystem, this provides a robust, end‑to‑end path from DNA to IND‑ready material.
CHO Cell Line
Genetically Engineered CHO Host Cell Line
- A rationally designed, genetically engineered host cell line with superior protein expression capabilities
- Fully documented and tested to meet cGMP regulatory standards
- Suspension growth in chemically defined medium
- Fast‑growing, with short doubling times of 15–16 h
- Long‑term stability over 70+ generations
Expression Vector
Highly optimized vector elements (including promoters, signal peptides, UTRs, and S/MAR elements) for increased expression and enhanced stability
A metabolic selection approach that eliminates the need for selective agents
Freedom-to-operate
Optimized for single- and multi-gene products
4Cell® SmartCHO Cell Culture Media
Chemically-defined, protein-free media and feeds
Designed to maximize the growth and productivity of our production cell lines
Suitable for both fed-batch and perfusion processes
Available in liquid (bottles and bags) and powder formats
Supply security from early development to commercial production
Co-designed to work synergistically with our engineered CHO host cell line to enable high, stable protein expression
Bioprocess Design
- Seamless tech transfer from Ambr® and benchtop bioreactors to pilot and GMP manufacturing scales (up to 2,000L)
Minimize the need for routine process optimization and scalability studies
Where appropriate, further optimization of process conditions and feeding profiles can be performed in high-throughput Ambr® 250 systems
A Genetically Engineered CHO Host Cell Line for Data-Driven Cell Line Development
In cell line development, successful outcomes depend on the performance of the core technology. Our engineered CHO host cell line provides a superior biological foundation, supporting higher productivity and robust stability. This enables reliable data generation in early development and more informed decision-making as the project progresses.
How was the host designed?
Through proteomic profiling, we mapped our CHO host cell and identified 67 endogenous proteins that are particularly energy-intensive. Using CRISPR‑mediated gene editing, we then performed a comprehensive knock‑out study to identify a target that significantly increases expression titers and productivity.
The result is a novel CHO host cell line* with substantial performance gains: up to 2-fold increase in titer and up to 3-fold higher cell‑specific productivity, while maintaining high and consistent product quality across different protein types.
What does this mean for your cell line development project?
When integrated into our cell line development platform, these host cell improvements translate into:
- Higher and more consistent productivity across mAbs, complex proteins, and biosimilars.
- Stable expression over extended cultivation periods, supporting reliable performance during process development, scale‑up, and tech transfer.
- Broader process versatility, including strong performance in intensified processes, with up to a 2‑fold titer increase in a 28‑day perfusion run.
Discover our CHO CLD Services in one quick read
*This new host cell line has freedom-to-operate and has no associated license fees.
Proven Success Across Diverse Modalities
Our CHO cell line development service team possesses a comprehensive skillset that extends to complex and challenging biomolecules, whether they are new biological entities or biosimilars. For every project, we tailor the vector and design custom workflows to meet the unique requirements of each molecule.
Historically, mAbs are the type of protein molecules with which we have the most experience. We have completed over 180 monoclonal antibody projects (IgG1-4), with titers reaching up to 10 g/L. More than 50 of these molecules have reached clinical stages, including 10 in commercial manufacturing and approved for market use.
Over the past decade, our service has supported the development of a variety of bispecific targeting molecules with diverse structures. We have successfully expressed IgG-like and non-IgG-like (lacking the Fc region) bispecifics for our clients. For all bi- and multispecifics, it is critical to closely monitor the chain assembly and molecule integrity. When identifying a suitable clone, we closely evaluate protein quality attributes like correct assembly, glycosylation pattern, and charge variants, reducing the risk of delays.
In total, we have completed close to 40 bispecific projects, with titers reaching above 7 g/L. More than a dozen of these molecules have reached clinical stages.
Our team has successfully developed cell lines expressing a diverse range of Fc-fusion proteins including proteins with enzymatic function, VHH nanobodies fused to an Fc region, glycoproteins fused to an Fc region, or even three-chain molecules with different Fc fragments. These projects involve significant downstream analysis by our experts to ensure that product-relevant characteristics, such as enzymatic activity, are preserved.
We have completed over 50 Fc-fusion protein projects, with titers reaching up to 7 g/L. More than a dozen of these molecules have reached clinical stages.
The absence of an Fc region in the protein of interest can create challenges during cell line development and production. However, with a track record of over 40 non-antibody product projects—including enzymes, hormones, and glycoproteins—and achieving titers of up to 8 g/L, we have demonstrated our ability to successfully address these obstacles. Nearly 10 of these molecules have advanced to clinical stages.
The lack of Fc region requires the implementation of molecule-specific solutions for titer measurement, protein quality analytics, and downstream processing. Furthermore, close monitoring is essential to ensure the correct protein assembly. Our expertise extends to complex projects, such as those involving the coexpression of an enzyme to support the cleavage of the protein of interest.
Our approach involves early screening and a flexible platform process (e.g., transfection processes can be adapted for co- or sequential transfection depending on the protein of interest).
Biosimilars
When developing a cell line for biosimilar production, achieving high titers and product similarity is crucial for market approval. We closely analyze the protein quality attributes of the originator batches, leveraging the biosimilar analytics expertise of the scientists at our biologics testing facility in Glasgow (UK).
During cell line establishment, we adopt a broad approach, expanding twice as many clones and screening more in small-scale fed-batch settings to select top performers for Ambr®15 cultures. We evaluate clones based on titer and post-translational modifications, customizing the expansion process to meet client expectations. Optional in-depth analytics are available on-site, aiding lead clone selection without delays. Once identified, we optimize processes and media to enhance titer and product quality attributes (PQAs), aligning with project finalization and tech transfers. We have successfully established around 30 biosimilar projects, achieving yields up to 9 g/L, with three molecules approved for market use.
Gedeon Richter Plc (Hungary)
We are satisfied with the whole project, project lead, and communication. The titer is amazing and gives us enough space to optimize the quality of our biosimilar. The challenge of achieving monoclonality of one clone was handled correctly and is therefore seen as positive.
Inside Sartorius CHO Cell Line Development Service
Sartorius, Your CHO Cell Line Development Partner
Sartorius’ state-of-the-art cell line development facilities in Ulm, Germany, can handle 50 projects annually, and new campaigns are initiated promptly after the gene sequences have been delivered.
We serve as a strategic ally, reducing financial and scientific uncertainty by providing customized workflows, data‑driven decisions, and clear technical guidance. Dedicated one-to-one technical and project support helps you interpret data at each stage and confidently steer the program towards IND.
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Elevating Your CHO Cell Line Development Journey
Every cell line development project is executed differently, but our proven workflows, robust technology, and unmatched expertise ensure reliability from DNA to IND filing. With flexible work packages, we tailor our offering to support your unique needs.
Explore the Steps in Our Workflow in More Detail:
Cell Line Development Customization Options
As cell line development projects progress, efficiency, performance, and scalability become paramount. Avoid becoming locked into a fixed service that won’t align with your internal workflows or future scalability needs, hampering your progression into clinical phases.
With Sartorius, your cell line development service package can evolve with your project. We offer adaptable solutions supported by diverse capabilities, embedded experts, and flexible work packages. Explore some of the customization options that we offer to secure your success and future-proof your process.
Our classical DNA to Pool approach involves establishing large pools, which can de-risk cell line development projects by facilitating the parallel evaluation of multiple molecule candidates. This approach includes evaluating pools through a fed-batch study to provide the necessary data (e.g., PQAs and expression performance) to inform the selection of the optimal construct and generate small-scale material for additional testing. This streamlines decision-making, saving time and resources and enabling the confident selection of the best construct for full cell line development.
These investigational activities can be performed at Sartorius or directly at the client’s facility using our Research Technology License for in-house DNA to Pool activities.
We also offer an alternative approach using mini pools for clients requiring a pre-defined quality profile for their molecule. Following transfection and mini-pool generation (and cell banking), we continue with small-scale fed-batch cultures to evaluate the pool variants and generate material. The goal is to identify the best mini-pool based on PQAs and advance to single-cell cloning. Ultimately, this approach ensures that the lead clone will exhibit the targeted quality profile and de-risk the overall cell line development program.
Both our large and mini-pool approaches can also generate early material for toxicology studies (up to 50 g), ensuring critical quality attributes (CQAs) are comparable to the final clone. This reduces the overall chemistry, manufacturing, and controls (CMC) timeline by enabling the initiation of upstream and downstream process development and formulation studies in parallel to the ongoing cell line development program.
Results derived from a cell line development campaign showing growth and viability (Left) titer (middle), and product quality (right) from bioreactor cultures of the pool and the lead clone.
Our FUT8 knockout cell lines enhance therapeutic efficacy and product consistency in biopharmaceutical development. These cell lines boost antibody-dependent cellular cytotoxicity (ADCC) by eliminating fucosylation and increasing antibody binding affinity to immune effector cells. They also ensure uniform glycosylation patterns for consistent and reliable products.
Our experts can support the integration of FUT8 knockout cell lines into your development process within 10 weeks, with genetic validation and functional confirmation performed using flow cytometry on the iQue® 3 screener. This process achieves long-term stable afucosylation without affecting productivity or performance. Our clients also have the freedom to use the technology license-free.
Internal development results showing growth and viability (left), titer and specific productivity Qp (middle), and product quality (right) for wild type (WT) vs. FUT998 knockout (KO) cell lines. Results are averages of the top four clones.
Our custom gene knockout service provides tailored solutions for specific production needs, including adjustments in growth characteristics, metabolic pathways, glycosylation patterns, and protein expression levels. With deep knowledge of our CHO host cell genome and advanced engineering tools, we precisely modify genes and pathways to ensure we develop optimized cell lines with long-term stability that meet regulatory standards without compromising performance.
The industry is shifting toward intensified processing to improve economic efficiency and sustainability. Upstream process intensification approaches can markedly increase productivity per bioreactor volume, so it is imperative to start thinking about strategies early.
We offer a range of Ambr® 15 and Ambr® 250 scale-down tools to directly select the best clones for perfusion or to implement high-inoculation fed-batch (HIFB) during cell line development. These tools also enable you to identify which intensification setup works best for your molecule.
Our cell line development workflow can be adapted to perfusion mode, using Ambr®15 clone screening and selection to under perfusion mimic conditions. The performance of the intensified process can then be evaluated and optimized further at benchtop-scale before scaling up.
Results from a cell line development campaign showing the top four clones (C2, C10, C22, and C24) cultured in the Ambr® 15 in standard fed-batch (FB) vs. perfusion (PI) mode (unoptimized) |
Internal development results showing the product titer over time from a lead clone at Ambr®250-scale in high-inoculation fed-batch (HIFB) mode and at 5 L-scale in standard fed-batch and HIFB mode. |
Our internal results show that HIFB doubles productivity compared to standard fed-batch by increasing titer and shortening the process duration by four days. The process also scales up well from Ambr® 250 to benchtop scale (5 L).
It is possible to switch from fed-batch to intensified processing even later in your cell line development process. While intensification capacity is strongly clone-dependent, most cell lines selected in fed-batch show significant potential for intensified processing.
Our experts can help you select the best perfusion clones from fed-batch data using our digital simulation tools. We can also perform media and process optimization activities with Ambr® 250 in a true perfusion setup for improved productivity and quality profiles.
Our proven and flexible approach ensures you achieve robust production beyond cell line development. By prioritizing long-term performance, scalability, and regulatory compliance during the early stages, we minimize risks during the transition to clinical and commercial phases.
Sartorius’ freedom to operate ensures seamless transferability of our cell lines, allowing you to move them to any CDMO of your choice. We have successfully transferred our cell lines to over 25 manufacturing service providers, from small to large size, in all regions.
We also offer the flexibility to transfer our cell lines directly to your facilities, providing you with complete control over your biopharmaceutical production processes.
Looking for a one-stop solution from cell line development to GMP manufacturing services? We have established strategic collaborations with selected CDMO partners worldwide to support a seamless, end-to-end development process. Our cell line development services have been integrated into their overall offering to streamline processes and allow our clients to benefit from both companies’ expertise:
Smooth transition and scale-up of Sartorius CHO cell lines into CDMO platforms with established manufacturing processes.
Strong coordination and harmonized timelines between Sartorius and CDMO teams facilitate seamless transfer
Predefined agreements and streamlined contract processes ensure favorable slot allocation and reliable media supply.
Comprehensive service from cell line development to drug product manufacturing, optimizing productivity and product quality
Collaboration with leading manufacturing partners and specialized cell line development providers for efficient handling of standard and complex protein molecules
What Cell Line Development Setup is Right for You?
Flexible Work Packages for Any Project
Our versatile service offering can be configured and customized to serve any project needs, allowing you to maintain control while benefiting from our advanced CHO cell development capabilities and expertise.
Choose a level of outsourcing, licensing, or hybrid support that best fits your needs, ensuring a seamless fit from early development through to commercialization.
We also ensure clear commercial terms with no hidden fees, royalties, or milestones. Flexible pay‑as‑you‑go models and transparent pricing help you confidently navigate budget constraints and maintain control through adaptive project management.
It is important to note that these work packages are not exhaustive. Please contact our cell line development experts to discuss how we can design a tailored project to fit your needs, including process optimization, material production, and analytics, for different kinds of molecules.
Outsourced Cell Line Development
Outsource your cell line development process (partially or entirely) to Sartorius as your extended laboratory bench and trusted drug development partner
In-House Cell Line Development
Get access to our cell line development technology for your in-house development, including our host cell line, vector, media, and methodologies.
