Principal Scientist, Biology

Xaira Therapeutics•South San Francisco, CA

2d•$164,000 - $205,000•Onsite

About The Position

Xaira Therapeutics is seeking a lab-based Principal Scientist in Inflammation and Immunology to join our Biology & Pharmacology department. This role is ideal for someone who combines hands-on research expertise with strategic program leadership, has experience working with primary human and mouse immune cells, including ex vivo tissue systems, and is excited to shape and drive therapeutic program strategy. In this role, you will set the scientific direction for one or more therapeutic programs, generate and advance new biology target ideas, and produce actionable data that moves programs forward through cross-functional collaboration. You will also serve as a key scientific voice to senior leadership, presenting findings and recommendations that inform program and portfolio decisions.

Requirements

PhD in Immunology or a related field with 6+ years of relevant experience.
Track record of impact through first-author publications, posters, and presentations at meetings
Demonstrated ability to independently define research strategy, plan and oversee complex experiments, and interpret data to guide program direction.
Experience generating and advancing novel target hypotheses, with the scientific judgment to prioritize among competing ideas.
Strong expertise in in vitro and ex vivo immunology, including primary immune assays, co-culture systems, target cell depletion assays, and high-parameter flow cytometry.
Proven ability to independently plan, execute, troubleshoot, and interpret experiments.
Comfortable and enthusiastic about leveraging AI tools to support research design, data analysis, and daily workflows
Highly organized and precise in record keeping, with the ability to manage multiple workstreams in a fast-paced environment.
Clear, confident communicator who can distill complex data into actionable insights for senior leadership and cross-functional partners. Proven ability to work effectively in team environments
Out-of-the-box thinker who brings a creative and innovative approach to identifying and validating novel targets, challenging conventional assumptions to uncover new opportunities

Nice To Haves

Single-cell RNA sequencing (scRNAseq), CRISPR/Cas9, and omics data analysis experience is a plus

Responsibilities

Drive program strategy by defining research priorities, designing and overseeing in vitro and in vivo studies, and guiding decisions on disease biology, target validation, and lead candidate development.
Generate and advance new biology target ideas by evaluating novel targets and therapeutic strategies and building the scientific rationale to move them into active programs.
Identify knowledge gaps, ask critical mechanistic questions to guide program direction, and shape experimental strategy across multiple workstreams.
Translate experimental data into actionable insights and present findings and recommendations to senior leadership and cross-functional teams to inform program strategy.
Stay hands-on at the bench, personally designing, executing, and troubleshooting key experiments, particularly for high-priority or technically challenging studies where direct expertise is needed to move a program forward.
Establish cell cultures using human/mouse primary tissues for downstream functional or phenotyping assays including: Immune profiling, using high-parameter flow cytometry (15+ colors), and molecular tools (ELISA, MSD, Luminex, qPCR, RNAseq analyses). Functional assays (antigen presentation, immune cell activation, differentiation, proliferation, suppression, migration)
Serve as a scientific leader and mentor within the department, contributing to the technical development of junior scientists and shaping best practices across the group, while continuing to model strong hands-on lab practice.