Senior Associate Scientist; I​/II), In Vivo Antibody Discovery

Mosaic Biosciences is a biotherapeutics drug discovery company that partners with biopharmaceutical companies to discover novel protein and antibody therapeutics. Our experienced and dedicated research teams collaborate with our partners to design, manage, and execute research programs to rapidly advance clinical candidates, starting at any point from early discovery into preclinical development.

We are hiring a full-time Senior Associate Scientist (I/II) to join our In Vivo Antibody Discovery team. In this role, you will play a critical part in executing hybridoma and/or single B cell screening workflows to identify and characterize antibodies for therapeutic use. You will work under the guidance of scientific leadership to support immunization studies, tissue processing, and high-throughput screening – generating the data that fuel Mosaic partners’ discovery campaigns.

This is a great opportunity for someone who is detail-oriented, curious, and excited to build something new alongside a close-knit scientific team.

• Support murine immunization studies including coordinating and scheduling
• Perform tissue processing and prepare samples for hybridoma fusion and/or single B cell workflows
• Facilitate execution of screening assays including ELISA, FACS, and plate-based binding formats to identify candidate antibodies
• Perform mammalian cell culture to support hybridoma expansion, antibody production, and screening activities
• Maintain detailed records of experiments and support data analysis and presentation
• Work cross-functionally with protein engineering and characterization teams to ensure smooth data handoff and support campaign timelines
• Contribute to ongoing workflow optimization through troubleshooting and process improvement

• B.S. or M.S. in Immunology, Cell Biology, Molecular Biology, or related discipline with 3-6 years of relevant lab experience
• Hands‑on experience with mammalian cell culture
• Experience working with in vivo antibody discovery methods is strongly preferred
• Ability to multitask, manage time effectively, and work both independently and collaboratively in a fast‑paced environment
• Strong attention to detail, communication, and organization skills
• Experience in biotech or CRO settings is strongly preferred

This is a full-time, in‑person position based in Boulder, CO.

$74,000 - $97,000 (Title and compensation will be determined based on experience and level)

Mosaic offers competitive, flexible benefits, including health and dental insurance, disability and life insurance, 401(k) with company match, and bonus opportunities based on company success.