Senior Principal Scientist

Virology - Principal Scientist / Senior Principal Scientist Location: Seattle, WA (onsite) Company: Venture-backed biotech (stealth mode) About the Company Were an early-stage, venture-backed biotech operating in stealth mode. Were building a small, high-performing team that moves quickly from question to experiment and works closely across disciplines to make clear, data-driven decisions. The Opportunity This will be the second scientist on our internal virology team. We are seeking a senior individual contributor who combines scientific leadership with substantial bench execution. This is a hands-on player-coach role. You will work alongside our Senior Scientist to expand live-virus neutralization capabilities, own and grow our viral strain library, and establish advanced human airway models in-house. Success will come from designing strong experiments, generating high-quality data, troubleshooting difficult methods, and helping a small team move quickly. What Youll Do Run live-virus neutralization and infectivity assays Design, optimize, and execute in vitro neutralization assays using live virus and, where useful, pseudovirus or reporter-virus systems. Perform and interpret TCID50, plaque, focus-forming, or related infectivity assays. Establish controls, acceptance criteria, and data-quality standards that support reproducible decisions. Troubleshoot assay performance across viral strains, cell substrates, reagents, plate formats, and readout methods. Improve throughput without sacrificing rigor. Own the viral strain library and stock quality Maintain a well-characterized library of viral strains, including sourcing, receipt, quarantine, inventory, passage history, master and working stocks, aliquoting, storage, and distribution. Propagate and titer viral stocks. Optimize cell substrate, multiplicity of infection, media, culture conditions, harvest timing, clarification, and freeze-thaw conditions when strains do not grow reliably. Sequence viral stocks to confirm identity, genetic integrity, and consistency with expected sequences. Review and document consensus changes and relevant minority variants. Create fit-for-purpose stock-release criteria and records that connect passage history, titer, sequence, sterility or contamination checks, and intended experimental use. Establish human nasal organoid and air-liquid interface models Develop and run infection and neutralization studies in human nasal organoids and/or primary human airway epithelial cells differentiated at an air-liquid interface (ALI). If these methods are new to you, train hands-on with our academic collaborators and rapidly transfer their protocols, critical reagents, quality criteria, and analytical readouts into our lab. Troubleshoot donor variability, epithelial differentiation, infection conditions, dosing, sampling, and virologic readouts to produce robust and interpretable data. Advance applied virology and lab operations Conduct serial-passage, escape-selection, plaque-purification, clonal-isolation, and fitness experiments as program needs evolve. Help scale day-to-day BSL-2 operations, including SOPs, biosafety practices, equipment readiness, sample tracking, inventory, and interfaces with facilities and vendors. Coordinate selected work with external laboratories and academic collaborators while retaining direct ownership of experimental design, data quality, and interpretation. Provide scientific leadership while remaining hands-on Work as a close technical partner to the existing Senior Scientist. Share methods, review data, and raise the quality and pace of the teams experimental work. Present concise data summaries, conclusions, and recommended next steps to scientific and company leadership. Author protocols, SOPs, technical reports, and relevant sections of regulatory documents. What Youll Bring Minimum qualifications Ph.D. in virology, microbiology, molecular biology, cell biology, or a related field, with 6+ years of relevant postdoctoral and/or industry experience. Meaningful industry experience is strongly preferred. Deep, recent hands-on experience propagating, quantifying, and troubleshooting live viruses in a BSL-2 environment. Demonstrated expertise developing and running cell-based neutralization or infectivity assays, including relevant controls, curve analysis, acceptance criteria, and assay troubleshooting. Experience managing viral stocks or strain collections, maintaining passage histories, and using sequencing to verify stock identity and quality. Strong mammalian cell-culture skills and a track record of diagnosing difficult strain-, cell-, or assay-dependent problems at the bench. Experience with human nasal organoids or ALI cultures, or closely related expertise in primary epithelial cells, 3D organoids, complex co-culture systems, or tissue-derived models that would enable rapid training and method transfer. Willingness to travel periodically to academic collaborators for hands-on training and to reproduce their methods internally. Strong documentation and data-integrity practices, with the ability to communicate experimental results clearly to specialists and non-specialists. A clear preference for a senior role that remains approximately 80% laboratory-based. Preferred qualifications Direct experience establishing and maintaining human nasal organoids, airway organoids, or primary airway epithelial ALI cultures. Experience working across multiple viral strains and cell substrates, including strains that require nonstandard propagation conditions. Practical experience with targeted amplicon or whole-genome sequencing, sequence alignment, variant review, and contamination or mixed-population assessment. Experience with serial passage under selective pressure, plaque purification, clonal characterization, and viral fitness studies. Familiarity with imaging-based infectivity readouts, qPCR or dPCR, and high-throughput plate-based workflows. Experience helping establish or expand BSL-2 laboratory capabilities in a startup or similarly resource-conscious environment. Traits for Success Hands-on and low-ego. You are comfortable setting scientific direction and then doing the experiments yourself. Resourceful and rigorous. You can troubleshoot an unfamiliar system, identify the variables that matter, and reach a defensible answer quickly. Collaborative and direct. You share credit, communicate clearly, and work well alongside another strong bench scientist. Comfortable in a small, lean company where priorities evolve and every scientist contributes at the bench. Tools & Environment (representative) Class II biosafety cabinets; CO2 incubators; adherent and primary cell culture; organoid and Transwell/ALI culture systems; plate readers and imaging platforms; centrifugation and sterile processing; plaque, focus-forming, and TCID50 workflows; qPCR/dPCR; targeted sequencing workflows; cold storage (-80 C/-20 C/4 C); ELN and sample/inventory tracking systems. Title & Level We expect to hire at the Principal Scientist or Senior Principal Scientist level, based on experience. This is a senior individual-contributor position. Mentoring and technical leadership are important, but direct laboratory work will remain central to the role. Why Join Us Join as the second member of the internal virology team and directly shape the methods, strain collection, and experimental standards that guide our programs. Build advanced human-relevant infection models in close collaboration with experienced academic investigators. Work with seasoned company builders and scientific leaders in a small team where strong bench science directly informs decisions. Equal Opportunity Employer. We celebrate diversity and are committed to building an inclusive environment for all employees. How to Apply : Please send your CV and a brief note highlighting your recent hands-on experience with live-virus neutralization, viral stock propagation and sequencing-based quality control, and human nasal organoid/ALI or related advanced cell-culture models. Work In Biotech