Scientist - Cell Line Development

ABOUT KYRON.BIO:Kyron.bio is redefining what biologics can be. Based in Paris, we precision engineer N-glycosylation to unlock new therapeutic behaviour in antibodies and biologics, improving immunogenicity, pharmacokinetics, and efficacy. We are the first company to combine cell line engineering, glyco-biodesign and therapeutic development to build next-generation mAbs. This work is unlocking a fundamentally new design space enabling biologics with efficacy and safety profiles that were previously out of reach. Kyron.bio is backed by top European investors, awarded the Servier Golden Ticket, and in 2025 was awarded a €2.5M grant from the European Innovation Council. We closed our seed round in May 2025, positioning us to advance our first glyco-engineered antibodies into in-vivo studies and expand into commercial cell line development. This is a growth stage, where building scalable upstream capability becomes foundational to our impact. ABOUT THE ROLE: We are hiring an experienced Scientist in Cell Line Development & Upstream Bioproduction to advance and scale our mammalian expression platform. You will lead the development of high-performance CHO cell lines, be responsible for optimizing upstream processes for reproducibility and yield and drive the generation of material for in vivo studies. As we move into our commercialisation phase, you will also be responsible for delivering high-quality, timely cell line development work for external partners. You will be instrumental in the scientific execution of partnered projects, ensure clarity and quality in documentation, and help build the capacity needed to serve a growing commercial pipeline. This is an opportunity to help shape how commercial CLD takes form at kyron.bio. If you enjoy autonomy, ownership, and building something with lasting impact, read on KEY RESPONSIBILITIES: Cell Line Development: Generate and optimise stable CHO cell lines for biologics production Perform transfections, selection strategies, clonal isolation and expansion Improve productivity, stability, and product quality through engineering and process design Build research cell banks, maintain lineage traceability, and track performance over time Upstream Bioproduction & Scale-Up:Develop upstream processes from shake-flask to small-scale bioreactor operation Optimise culture conditions, feeds, media and bioreactor operation parameters for productivity & glycosylation profile quality Produce material for in-vitro characterisation and in-vivo studies with reproducibility Cross-Functional Impact:Work closely with protein engineering and therapeutic development teams Maintain rigorous experimental design, structured reporting, and organised data flow Bring an industrial mindset: robustness, timelines, reproducibility and decision-making through data Coordinate with internal teams and external partners to ensure smooth execution of commercial CLD studies YOUR PROFILE: Required:Industry experience (2+ years) in biotech/pharma essential (cell line development or upstream bioprocessing) PhD in relevant field including bioengineering or biotechnology (exceptional MSc graduates also considered) Hands-on experience with stable mammalian CHO cell line development including: transfection & selection single-cell cloning productivity screening cell production evaluation & RCB generation Upstream production experience from flasks and into scalable systems (experience with high-throughput systems is preferred) Strong molecular biology & cell culture fundamentals Fluent in English, able to communicate clearly in data-driven and decision-driven discussions Thrives in an early-stage environment, independent, resourceful, execution-oriented Bonus / Highly Valued: Exposure to commercial CLD work, external partnerships or CDMO-style workflows Antibody production experience (expression, harvest, titer assessment, purification) Experience in glycosylation analysis or protein quality characterisation Experience with bioreactors (any platform) Previous startup experience French language skills WHAT WE OFFER: Early ownership of a core technical platform, your work will define how kyron.bio scales Competitive salary package with growth opportunityMeal vouchers & Public transit pass covered at 50%A high-trust, high-impact environment where execution matters and science moves fast A seat at the table as we establish commercial CLD as a strategic business line The chance to build therapeutics and capabilities that don’t exist today PRACTICAL DETAILS:Location: Paris Biotech Santé (Paris 14e) Start Date: 2026, asap Contract: Full-time, in-personHOW TO APPLY:LinkedIn applications will NOT be considered. Please only apply through the following form:https://airtable.com/appswwOYys0KWowKc/shr1h3mZRfDqum0Ig