Principal Biologist/Senior Principal Biologist, Immune Aging

Job ID: R-109167Company: LillyLocation: San Francisco, California, United States of AmericaJob Type: Full TimeCategory: Research & DevelopmentPosted Date: 2026-08-05At Lilly, the work is demanding because patients are waiting. We unite caring with discovery to help make life better for people around the world, knowing that every decision, every detail, and every day matters. Headquartered in Indianapolis, Indiana, our over 50,000 employees around the globe take on complex challenges to discover and deliver life-changing medicines, strengthen how health is understood and managed, and support the communities we serve. This is hard, urgent, selfless work—but it’s work worth doing. If you’re driven by purpose and ready to bring your best to work that truly matters for patients, we invite you to join us. Lilly is building an exploratory research effort centered on immune aging, with active programs in T cell biology, cellular reprogramming, CAR-T applications, and the immune–stromal interactions that sustain chronic inflammation. We are hiring a Principal Biologist to serve as a hands-on technical driver of this work, executing experiments on programs designed by the project lead, generating decision-grade data, and contributing recognized bench expertise in primary human immune cell biology.Key ResponsibilitiesExecute primary human immune cell experiments across multiple projects under the direction of the project lead, including isolation, culture, and functional characterization of T cells and other immune populations.Design and run multiparameter flow cytometry and complementary molecular and cellular assays to interrogate target biology, including panel design, FACS sorting, multiplex cytokine quantification, Western blot, qRT-PCR, co-culture systems, and functional readouts of T cell activity and senescence.Deliver decision-grade data through rigorous controls and pre-specified analysis plans; troubleshoot independently using evidence-based reasoning; and surface limitations and unexpected findings proactively.Communicate results clearly through written summaries, presentation-quality figures, and team scientific reviews, while maintaining disciplined experimental records.Basic QualificationsMaster’s degree in Immunology, Cell Biology, Molecular Biology, or a closely related discipline, with 3+ years of industry research experience; or a Bachelor’s degree with 5+ years of industry research experience.Experience with immunoassays (ELISA, MSD, HTRF), multi-color flow cytometry (staining, acquisition, and analysis in FlowJo), and protein detection methods such as Western blotting.Preferred QualificationsWorking knowledge of cell and molecular biology concepts and a strong grasp of underlying assay principles.Hands-on experience with cell lines, whole blood, and isolation and culture of primary human immune cells.Demonstrated ability to operate and troubleshoot independently, with consistent, reproducible execution and strong technical communication.Experience with cellular and biochemical assays in 96- and 384-well formats.Research experience with small molecules, biologics, and/or genetic medicine modalities.Experience with lentiviral and retroviral systems.Light computational competence for flow data analysis (FlowJo) and basic data wrangling; deep computational expertise is not required.Additional InformationCurrent US work authorization is required.Lilly is dedicated to helping individuals with disabilities to actively engage in the workforce, ensuring equal opportunities when vying for positions. If you require accommodation to submit a resume for a position at Lilly, please complete the accommodation request form () for further assistance. Please note this is for individuals to request an accommodation as part of the application process and any other correspondence will not receive a response.Lilly is proud to be an EEO Employer and does not discriminate on the basis of age, race, color, religion, gender identity, sex, gender expression, sexual orientation, genetic information, ancestry, national origin, protected veteran status, disability, or any other legally protected status.Our employee resource groups (ERGs) offer strong support networks for their members and are open to all employees. Our current groups include: Africa, Middle East, Central Asia (AMECA), Black Employees at Lilly (View email address on click.appcast.io), Chinese Culture Network (CCN), EnAble, Evolve, Lilly Indian Network (LIN), Organization of Latinx at Lilly (OLA), Pride (LGBTQ+ Allies), Veterans Leadership Network (VLN) and Women’s Initiative for Leading at Lilly (WILL).Actual compensation will depend on a candidate’s education, experience, skills, and geographic location. The anticipated wage for this position is$71,250 - $187,000Full-time equivalent employees also will be eligible for a company bonus (depending, in part, on company and individual performance). In addition, Lilly offers a comprehensive benefit program to eligible employees, including eligibility to participate in a company-sponsored 401(k); pension; vacation benefits; eligibility for medical, dental, vision and prescription drug benefits; flexible benefits (e.g., healthcare and/or dependent day care flexible spending accounts); life insurance and death benefits; certain time off and leave of absence benefits; and well-being benefits (e.g., employee assistance program, fitness benefits, and employee clubs and activities).Lilly reserves the right to amend, modify, or terminate its compensation and benefit programs in its sole discretion and Lilly’s compensation practices and guidelines will apply regarding the details of any promotion or transfer of Lilly employees.#WeAreLillySkillsprimary human immune cell isolationflow cytometrywestern blottingqrt-pcrmultiplex cytokine quantificationfacs sortingimmunoassays (elisa, msd, htrf)protein detection methodscellular reprogrammingcar-t applicationsimmune–stromal interactionsscientific communicationdata analysis96-well format assays384-well format assayslentiviral systemsretroviral systemscell line isolation and culturewhole blood isolation and culturesmall molecule researchbiologics researchgenetic medicine research