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Principal / Sr. Principal Scientist, Immunology

Company Overview

Janux Therapeutics is a biotechnology company based in San Diego that is leveraging an innovative and proprietary discovery platform to efficiently develop tumor-activated drugs that empower the immune system to eradicate cancer. Janux is developing unique immunotherapies that generate tumor-specific immune responses to attack and kill tumors without destroying a patient’s healthy tissue. As an early-stage startup company, Janux is looking for energetic and talented candidates who desire to work in a fast-paced and dynamic team environment. We believe that the whole team contributes to the overall mission. We succeed as a team, and we grow as a team.

Job title: Principal / Sr. Principal Scientist, Immunology

Job Summary:

Janux, Inc. is seeking a highly motivated Principal / Sr. Principal Scientist with demonstrated skills in and deep understanding of the field of cancer immunology, T cell biology and therapeutic antibody development. The candidate will characterize and develop large molecules in close collaboration with senior management as an integral member of the drug discovery team. The individual will provide scientific and technical expertise in efforts to understand drug-induced innate and adaptive immune responses against cancer. 

This position is hands-on and requires effective communication and documentation of results that enable the advancement of novel research molecules towards development candidates and IND-enabling stages. The successful candidate will have extensive hands-on experience with standard immunological and cancer biology techniques (Flow cytometry, T cell activation and extensive immunophenotyping, tumor cell killing, ELISA, gene expression assays, etc.). The ideal applicants will be collaborative and team-oriented, prosses excellent communication and organizational skills, and carry a strong commitment to excellence. Experience with program management and mentoring PhD and non-PhD scientists is required.

Education and Experience Requirement:

  • PhD with a postdoctoral training and 3+ years of relevant pharma or biotech industry experience managing programs in the field of immuno-oncology and/or biologics development. 
  • Proven track record of success in immunology, immuno-oncology, or related fields demonstrated by strong publication record (first author papers in high-impact journals) and training from top universities. 
  • Current knowledge of immuno-oncology research, drug discovery and development, with emphasis on immune cell activation, checkpoint inhibition, and T cell exhaustion pathways, as well as markers and assays to evaluate anti-tumor efficacy.
  • Direct experience with bispecific antibodies and / or T cell engagers and in-depth understanding of T cell subsets is highly desired.
  • Proficiency in isolation, culture, activation, and differentiation of primary human immune cells (mainly T cells, PBMCs and TILs).
  • Proven experience with assays evaluating immune cell functional and exhaustion status, as well as cell-mediated tumor killing.
  • Understanding of T cell signaling pathways and experience with signaling assays and readouts is highly desired. 
  • Experience with 3D organoid/tumoroid cultures and functional assays is a strong advantage.
  • Knowledge of protease biology is a plus.
  • Proficiency with multi-color flow cytometry (15+ parameters), including specialty assays (proliferation, cytokines, cytotoxicity, phosphor-flow, apoptosis, etc.) and proficiency using FlowJo and GraphPad Prism software.
  • Experience setting up immuno-oncology specific in vitro model systems.
  • Effective management and experience mentoring PhD and non-PhD scientists are required.

Role Responsibilities:

  • Oversee all aspects of assay design, optimization, validation, and implementation. 
  • Identify and integrate technologies that improve or expand the ability to assess the mechanism of action of novel immunomodulatory agents.
  • Design, conduct, analyze and interpret in vitro and ex vivo functional assays to assess mode of action and therapeutic potential of tumor-selective T cell modulators.
  • Execute experiments evaluating T cell activation, co-stimulation, cancer cell targeting, cytotoxicity, T cell signaling, gene expression. 
  • Perform functional molecule screens to help advance programs from hits to leads to development candidates.
  • Lead from the bench by providing direct supervision and mentoring to PhD and non-PhD level scientists.
  • Actively contribute scientifically to immunological drug discovery research programs, including identification and validation of new targets.
  • Support identification and prioritization of high-impact research activities.
  • Keep up with published literature centered around cancer targets and immuno-oncology therapies directly relevant to Janux programs.
  • Establish and manage relationships with external research collaborators and CROs.
  • Help manage internal laboratory activities under tight timelines.

Required Key Attributes:

  • Creativity to design and engineer complex assays that address target-specific biology.
  • Excellent oral and written communication skills.
  • Candidate must have effective troubleshooting and problem-solving skills.
  • Success in this role requires great attention to detail with the ability to multitask.
  • Candidate must be an effective team player, strong individual contributor, self-motivated, flexible, and able to manage multiple tasks and deliver high-quality results under tight timelines.
  • Highly organized and diligent about documentation.


Janux offers a competitive compensation with stock options in addition to a comprehensive benefits package consisting of medical, dental, vision, and supplemental disability insurance.

JOB TYPE: Full-time


  • 401K (3% employer matching)
  • Medical insurance
  • Dental insurance
  • Vision insurance
  • Supplemental disability insurance plans
  • Flexible schedule
  • Life insurance
  • Flexible vacation
  • Incentive stock option plan


Monday to Friday On-Site (La Jolla, CA)

COVID-19 Vaccination required

Janux requires all new hires to be fully vaccinated for COVID-19 prior to the first date of employment. As required by applicable law, Janux will consider requests or Reasonable Accommodations.


United States (Required)


Janux Therapeutics, Inc. is an equal opportunity employer that is committed to providing a work environment free of harassment and discrimination based upon a protected category, as well as an environment free from retaliation for protected activity.