Summary
- The problem
- Clone selection draws on identity, clonality, screening, product-quality and stability evidence held in different instruments and files. A high titre is easy to see; missing results and non-comparable conditions are not.
- Seal’s approach
- Protocols are configured and executed in Seal, and each candidate’s identity, images, culture context and results stay connected. Neil can assemble the comparison and draft the assessment; the scientists retain responsibility for selection.
- What changes
- The selection record shows the candidates considered, the evidence reviewed, what was missing and why one progressed, and it carries the chosen lineage into cell banking.
- Where to start
- A real selection question, the available candidate records and the programme’s criteria. Book a demo.
A protocol for every stage of CLD.
Cell line development usually keeps clone identity in a tracker, culture data in notebooks and analytical results in separate reports, so a selection decision is argued from a slide. Screening, expansion and stability protocols run in Seal as configured workflows that capture clone identity, passage, samples and observations through the work. The lineage is carried into the next experiment and, once a clone is chosen, into the cell bank that starts manufacturing.
Passage stability study
- Identify the clone and passage
- Record the culture and collect samples
- Link productivity and quality results
CL-19 / passage 30
- Candidate
- CL-19
- Planned passage
- 30
- Later titre
- Not recorded
Later-passage evidence outstanding
Configure with Neil. Test with your team. Reuse the protocol.
Each run keeps its own values, evidence and history.
Choose with more than titre.
Compare early and later passages before taking a candidate forward.
Cell line development selects the biological candidate that may become the starting material for a manufacturing process. The decision draws on construct and candidate identity, clonality evidence, growth, productivity, product quality and stability. A high titre is useful evidence, but it is not a complete selection decision.
Each result needs its culture and analytical context: passage, culture format, working volume, recipe, harvest age, method version and units. Seal keeps that context with the result, so a comparison states its basis and shows where observations are not alike.
In the fictional study below, three candidates were cultured at passages 10 and 30. CL-12 has the highest early titre, 4.6 g/L, but reports 3.2 g/L at passage 30. CL-07 changes little, from 3.8 to 3.6 g/L. The later result for CL-19 has not been reported, so it stays in view without being ranked as stable. Select a clone to see how Neil reads the evidence.
Titre across passages
Inspect the study records
UP-08 v02 · 15 mL fed-batch · passages 10 and 30. Titre method TTR-02 v03; early-harvest SEC method SEC-04 v02.
| Record | Clone | Early / late titre | Early SEC monomer |
|---|---|---|---|
| CLD-031 | CL-07 | 3.8 / 3.6 g/L | 98.8% |
| CLD-032 | CL-12 | 4.6 / 3.2 g/L | 97.1% |
| CLD-033 | CL-19 | 4.2 / Missing g/L | 99% |
One observation per displayed condition, not replicate means. Other quality attributes and clonality evidence are not supplied. The later result for CL-19 has not been reported.
The highest titre is not the whole answer.
The highest early titre falls at the later passage. Check the culture records and repeat evidence before attributing the difference to stability.
CL-12: 30.4% lower titre at passage 30
Read the draft selection assessment
Keep three candidates in the review.
CL-07 has the smallest observed titre difference. CL-12 starts higher but drops at passage 30. CL-19 is incomplete. These observations do not establish a lead clone.
Before advancing a candidate
- Review matched culture conditions and replicate evidence for the passage comparison.
- Complete the product-quality panel and later-passage result for CL-19.
- Review clonality, lineage and stability evidence against the programme’s selection criteria.
Draft based on CLD-031–033. No clone is selected or bank released by this example.
These observations raise questions; they do not establish genetic stability or choose a clone. A difference between passages may have several explanations, so the assessment asks the team to check the culture conditions, replicate evidence and the programme’s stability design. Missing measurements stay missing, and a repeat does not erase the original observation.
Neil can assemble the comparison, expose gaps in analytical coverage and draft the selection assessment. It does not reduce different kinds of evidence to a single score unless the team has defined and justified that method. The scientists make the selection.
From the first candidate to the cell bank.
Keep the complete selection history, not only the winning clone.
Connect the construct, source population, plate and well, isolation record, images, expansion history and candidate identifier, so later samples resolve to the same candidate even when instruments or laboratories use different identifiers. Keep the distinction between an image being present and a reviewer concluding that it supports clonality. If a sample cannot be traced confidently, the uncertainty stays with it rather than the result being attached to the apparent best match.
The selection record keeps the candidates considered, the evidence reviewed, the criteria, exclusions, open questions and the scientist’s rationale, with the source versions, so a later reviewer can see what was known when the decision was made. After selection, the chosen lineage connects to bank, vial, characterisation and storage records.
Identity and clonality
Keep construct, well, image and lineage evidence attached to the candidate throughout screening and expansion.
Screening and quality
Compare productivity with growth, viability and product-quality results. Expose missing tests and differences in methods.
Stability and selection
Bring passage studies, replicate evidence and programme criteria into a reviewable selection assessment.
Banking and handoff
Carry the selected lineage, characterisation and restrictions into bank records and the upstream development programme.
Keep screening data connected to the decision.
Bring in the screening files.
Start with imaging and screening files, culture observations and analytical results. Use exports or scope a permitted connection to the systems your team already runs.
Explore connectionsThen develop the culture process.
Clone selection and upstream process development are different jobs. Give the upstream team the selected cell source and its supporting evidence, then develop media, feeds and culture conditions.
Explore upstream developmentAQuestions and answers
Can we configure and execute protocols in Seal?
Yes. Configure reusable protocols with instructions, fields, calculations, linked samples and review steps. Each execution retains the version used, recorded values, observations and results. Neil can help prepare the configuration and analyse the resulting evidence; your team tests the workflow and defines the review and approval requirements for its intended use.
How is CLD different from upstream process development?
CLD evaluates and selects the biological candidate using lineage, clonality, productivity, quality and stability evidence. Upstream process development then establishes how to culture that cell line or strain: media, feeds, control strategy and scale-up. The records connect, but the decisions are distinct.
Does Neil select the production clone?
Your scientists make that decision. Neil can assemble a comparison, expose missing or non-comparable results and draft the selection assessment. Titre alone does not establish stability, clonality, product quality or suitability for manufacturing.
Can we use existing screening and bioreactor systems?
Start with exports or scope a permitted connection to your imaging, screening, bioreactor, historian and analytical systems. Preserve candidate and sample identities, units, timestamps and method versions. Availability depends on the source interfaces; this example is not a live instrument connection.
What happens after clone selection?
Keep bank and vial identity, passage history, seed expansion, media and feed versions with each culture. Compare actual process conditions and analytical results across studies. Fed-batch and perfusion studies have different calculation and time-window requirements; the comparison must retain those differences.
Can a development process be transferred to manufacturing?
The chosen recipe, material definitions, parameter rationale, scale assumptions and supporting studies can become a reviewable transfer package. Receiving equipment, local conditions and verification remain explicit work; matching setpoints do not establish scale equivalence.
What do the clone comparison numbers represent?
These are fictional day-14 fed-batch observations under recipe UP-08 v02 at a 15 mL working volume. Early and late refer to passages 10 and 30. Each displayed titre is one reported observation, not a replicate mean. SEC monomer results are from early-passage harvests only. The example does not supply a full quality panel, clonality evidence or a completed stability assessment.