Senior Scientist-Principal Scientist Antibody Protein Engineering

Prellis Biologics combines novel machine learning, biology at scale, and next-gen antibody discovery to address long-standing industry-wide problems in the drug development pipeline. Using proprietary technology to 3D print human lymph node organoids, we enable rapid and diverse discovery of human antibody therapeutic candidates for a range of applications. We are assembling a team of discovery biologists, computational scientists, and protein scientists to drive this mission forward.

About the role

We are seeking a Senior / Principal Scientist — Antibody Protein Engineering to join our High Throughput Discovery group. You will drive antibody design and optimization, maturing early hits into development-ready leads. The ideal candidate will thrive in a dynamic, hands-on environment and play a critical role in delivering life-changing therapeutics.

Responsibilities

• Lead antibody engineering with a strong emphasis on late-stage design and optimization to refine and advance lead candidates toward development.
• Reformat biologics across modalities (scFv, scFv-Fc, minibodies, Fab, VHH, Fc fusions, albumin fusions, TCRm) and assemble multispecifics (knob-in-hole, CrossMab, DVD-Ig, common LC, DARTs).
• Fc engineering — mutations for half-life, effector-function modulation, isotype selection, and bispecific heterodimerization.
• Affinity maturation — design focused libraries to improve affinity, kinetics, and specificity.
• Polishing & developability — remove chemical liabilities, mitigate aggregation and immunogenicity, humanize when needed.
• Screening & library construction — design and execute campaigns (alanine scanning, high-diversity libraries via PCR, Gibson, mutagenesis, oligo-pool synthesis); generate ML training-data campaigns; translate manual workflows to automation.
• Computational design — apply structural tools (PyMOL, Schrödinger BioLuminate / Maestro) and partner with Data Science / AI/ML on protein language and structure models (AlphaFold, ESM, RFdiffusion, ProteinMPNN, or equivalent).

Qualifications

• Ph.D. in Biochemistry, Bioengineering, Molecular Biology, Protein Engineering, or related field with equivalent industry experience: Sr. Scientist (PhD + 3-5 yrs); Principal Scientist (PhD + 5+ yrs).
• Hands-on biologics reformatting across scFv, scFv-Fc, Fab, Fc fusions, VHH, and Fc engineering.
• Demonstrated experience optimizing / engineering antibody lead candidates (affinity, developability, and Fc properties).
• Hands-on experience with biologics screening using iQue and MACSQuant or high content imaging (HCI).
• Computational fluency: PyMOL, Schrödinger (BioLuminate / Maestro), molecular dynamics, or equivalent, and at least one protein language model (ESM, RFdiffusion, ProteinMPNN, or equivalent).
• Strong molecular cloning, mutagenesis, and DNA library construction.
• Mentorship of junior researchers; clear scientific communication; track record of publications, presentations, or patents.
• Experience managing external vendors (CROs / CDMOs) for biologics production and characterization.
• Thrive in cross-functional collaboration.

Bonus Experience

• Strong background in antibody discovery pipelines: expression, purification, screening, and analytical characterization.
• Experience with continuous directed evolution (OrthoRep, PACE): high-diversity libraries (yeast, ribosome, mRNA, mammalian), multi-round selection, and quantitative affinity binning.
• Liquid-handling automation (Biomek, Lynx, Tecan), LIMS / ELN (Benchling).

About Prellis

At Prellis, we integrate human biology with machine learning to revolutionize drug discovery. Our goal is to harness the power of the human immune system with tightly integrated machine learning to develop next-generation antibody therapeutics with unparalleled speed, precision, and safety. We empower pharmaceutical partners with access to fully human antibody candidates rapidly identified from the human immune repertoire, enabling them to bring life-changing treatments to patients faster than ever before.

Prellis Biologics is a pre-IPO biotech located in Berkeley, CA with a team-oriented, inclusive, and family-friendly culture. Our growing pipeline targets high unmet patient needs across therapeutic areas including metabolic disease, inflammation, and oncology. Prellis has raised funding from top investors, including Celesta, Khosla Ventures, SOSV, and Avidity Partners.

Benefits

• A competitive employee benefits package, including group medical, dental, and vision coverage, life and disability insurance, flexible spending accounts, and a 401(k) plan.
• Stock-based long-term incentives.
• Holiday package including a 1+ week winter shutdown.
• Flexible work models, including remote and hybrid working arrangements, where possible.