Senior Scientist, Protein Sciences

Strand Therapeutics is a clinical-stage biotechnology company pioneering programmable mRNA therapeutics to unlock the full potential of genetic medicines. Strand is applying its proprietary Signal Stack platform, which integrates Ever Script circular RNA, AmpliScript self-replicating RNA, Signal Path targeted delivery, and logic-driven Signal Lock genetic circuits to enable precise control of therapeutic activity across tissues and cell types and overcome foundational limitations in targeting, durability, and safety.

Strand is advancing a pipeline with an initial focus on oncology and autoimmune disease. Its initial program, STX-001, an intratumorally delivered LNP-encapsulated self-replicating RNA expressing IL-12, has demonstrated preliminary evidence of systemic immune activation and anti-tumor activity in patients with advanced solid tumors who have progressed on prior therapies. Building on this early clinical validation, intravenously delivered STX-003 is designed for tumor-targeted expression and avoidance of off‑target expression.

STX-003, which is expected to enter the clinic in mid-2026, has the potential to be a major step forward for the fields of genetic medicine and oncology. Strand is also advancing STX-005, an in vivo CAR‑T program designed to enable controlled, durable expression and repeat dosing. Founded by MIT synthetic biology pioneers, Strand has raised over $250 million and is headquartered in Boston, MA.

Become the next standout single strand!

Strand is seeking a highly motivated and innovative Senior Scientist of Protein Sciences to join our Platform Enabling Technologies team. This founding role will establish and lead protein science capabilities that enable the discovery, engineering, and validation of protein payloads, binders, and reagents for Strand’s programmable RNA medicines.

Reporting to the Associate Director of Platform Enabling Technologies, the ideal candidate combines deep expertise in nanobody or antibody engineering, computational protein design, high-throughput protein purification and characterization, and enthusiasm for building new scientific functions while remaining active on the bench.

This role integrates experimental protein sciences with AI-enabled design to discover and optimize antibodies, nanobodies, and other therapeutic proteins. Working closely with our computational biology, RNA biology, delivery, and translational teams, the scientist will define protein design criteria, lead experimental validation, and connect molecular attributes, including expression, folding, secretion, stability, activity, and develop ability as recombinant protein and following RNA delivery.

• Establish and lead the Protein Sciences function by defining the scientific priorities, managing external vendors, selecting technology and instrumentation, and building workflows for binder discovery, protein engineering, production, and characterization.
• Build antibody, nanobody, or other binder modalities & discovery capabilities that integrate computational modeling, library design/construction, display-based high-throughput screening, and downstream validation to discover and optimize single domain and other antibody-derived binders
• Partner with Computational biology to develop an AI-enabled protein design platform by defining experimentally relevant design criteria, generating high-quality training and validation datasets, and testing model-generated candidates.
• Lead binder discovery projects against therapeutically relevant targets by leveraging external partners and internal platform capabilities
• Develop fit-for-purpose recombinant protein expression and purification workflows in in mammalian, yeast, and bacterial systems to support rapid design-build-test-learn cycles.
• Establish biochemical, biophysical, and cell-based assays to evaluate binding kinetics, specificity, purity, stability, aggregation, activity, and develop ability.
• Partner with RNA biology teams and delivery teams to optimize RNA-encoded proteins for translation efficiency, folding, intracellular trafficking or secretion, functional activity, duration of expression, and compatibility with the intended delivery modality.
• Design orthogonal assays that distinguish RNA, delivery, and protein-level drivers of performance and use the resulting data to guide construct and formulation optimization.
• Communicate data, risks, and recommendations clearly to multidisciplinary project teams and contribute to…