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Prellis Biologics

Prellis Biologics

Software Engineering
San Francisco, CA, USA
Posted on Wednesday, August 2, 2023

Prellis Biologics employs proprietary technology to 3D print lymph node organoids, which we are using to generate in vitro antibody libraries, camelid antibody libraries, in vitro human immunogenicity screening, and in vitro human tumor/lymph node cocultures for therapeutic screening. Prellis’ ability to print and culture healthy human tissue provides it with unique opportunities for generating and evaluating next-generation human therapeutics.

Prellis Biologics is seeking a Chemist to characterize antibodies and cell culture supernatants that are generated from Externalized Immune System (EXIS™) workflows. This role will involve developing sensitive assays to quantify antigen-specific antibody concentrations in cell culture supernatants collected from lymph node organoids. The job will also involve measuring antibody binding affinities using biolayer interferometry on an Octet system. The person in this role will synthesize new protein conjugates for EXIS workflow development and will work with the team to test the new reagents. The ideal candidate will be comfortable performing careful experiments and working hands-on in the laboratory on a regular basis. 


  • Develop assays to quantify antigen-specific antibody concentrations in lymph node organoid supernatants. Quantify the detection limits of assays. Collaborating with the team to optimize EXIS workflow conditions based upon assay results. 

  • Measure the binding affinity of antibodies produced from EXIS runs using biolayer interferometry (Octet). 

  • Synthesize and purify protein conjugates to support EXIS workflow development. This may involve conjugating small molecules, fluorophores, and biomolecules to proteins of interest. 

  • Formulate tetramer-based cell staining reagents for flow cytometry studies. 

  • Collaborate with internal teams to test the performance of protein conjugates and other reagents that are developed. Troubleshoot issues as needed. 

  • Document standard operating procedures (SOPs) for assays and reagent preparations. Maintain detailed experimental records. 

  • Define quality control (QC) tests and relevant metrics for new reagents that are developed. 

Preferred Qualifications:

  • Ph.D. in Chemistry, Biochemistry, Chemical Engineering, or Bioengineering with a strong academic record. Outstanding M.S. candidates with relevant experience will be considered. 

  • Hands-on experience with analytical techniques such as MSD electrochemiluminescence assays, Octet, ELISAs, UV-Vis spectroscopy, fluorescence spectroscopy, and liquid chromatography is desired. 

  • Rigorous scientist with a record of designing and executing careful experiments, maintaining detailed experimental records, and developing robust, transferrable processes. 

  • Experience with cell culture and familiarity with basic molecular and cell biology techniques are nice to have. 

  • Strong written and oral communication skills. 

  • Able to thrive in a dynamic, collaborative start-up environment. 

Please send your resume to careers@prellisbio.com to apply.

Prellis is committed to the principles of equal employment opportunity. Applicants are considered for all positions without regard to race, sex, sexual orientation, color, religion, national origin, age, and disability (so long as such disability can be reasonably accommodated) or any other status protected by applicable law. Prellis encourages all qualified applicants to apply.