About

Shang Song is the Frank L. and Daphna Lederman Professor of Biomedical Engineering at the University of Arizona. Her research involves deploying novel engineering approaches and biomaterials to manipulate cellular microenvironments, facilitating the development of regenerative medicine therapies and organ-on-chip systems across the neural axis, including the brain, spinal cord, and peripheral nerves. Her work is supported by prestigious awards such as the NIH Director's New Innovator Award and the American Heart Association. Dr. Song earned her BS with honors in biomedical engineering from Brown University, supported by the Gates Millennium Scholarship, and her PhD in bioengineering through a joint program at UC Berkeley and UCSF, followed by postdoctoral training at Stanford University. Her previous projects include implantable bioartificial pancreases for Type 1 Diabetes, electrically-stimulated stem cell therapies for stroke and nerve injury recovery. She grew up in Guam with her Chinese immigrant parents and is passionate about helping first-generation college students and students from nontraditional backgrounds.

Research topics

• Materials science
• Biology
• Medicine
• Anatomy
• Computer Science
• Biomedical engineering
• Cell biology
• Artificial Intelligence
• Electrical engineering
• Engineering
• Pathology
• Neuroscience
• Internal medicine

Selected publications

• Integrating Cells, Biomaterials, and Advanced Engineering for Next-Generation Peripheral Nerve Repair

  Cells Tissues Organs · 2026-05-22

  articleSenior author

  BACKGROUND: Peripheral nerve injuries (PNIs) disrupt sensory and motor circuits, affecting millions worldwide and often resulting in lasting functional deficits. Autologous nerve grafting remains the surgical benchmark for segmental defects, yet limited graft length, donor-site morbidity, and inconsistent outcomes-particularly in long (>30 mm) or proximal lesions-underscore the need for engineered alternatives. Although parallel strategies seek to enhance autograft outcomes (e.g., polyethylene glycol [PEG] fusion, growth-factor sleeves, post-repair electrical stimulation [ES]), this review focuses specifically on engineered replacements. Over the past decade, convergent advances in cell biology, biomaterials science, and biofabrication have produced tissue-engineered conduits intended to serve as effective alternatives to autografts . Unlike previous reviews that address these domains separately, this work treats cells, biomaterials, and advanced engineering as a unified design problem, benchmarking outcomes with standardized quantitative metrics across both short-gap rodent and long-gap large-animal models and articulating specific design-readiness targets as a translational framework. SUMMARY: This review synthesizes the past decade (2015-2025) of progress, identified through a structured narrative search of PubMed, Google Scholar, Web of Science, and Scopus (160 articles included), in three domains: (i) cell-based therapies, including Schwann cells (SCs), mesenchymal stem cells (MSCs), induced pluripotent stem cell (iPSC)-derived glia, neural stem/progenitor cells (NSCs/NPCs), and olfactory ensheathing cells (OECs), emphasizing their roles in neurotrophic support, immunomodulation, and remyelination; (ii) biomaterial scaffolds, spanning natural polymers, synthetic polymers, and hybrid composites, with design parameters tailored to mimic native nerve microarchitecture and degradation timelines; and (iii) integrated strategies that couple living cells with architecturally and biochemically instructive scaffolds, including pre-seeded conduits, injectable hydrogel systems, conductive/electroactive designs, and three-dimensional (3D) bioprinted constructs. Functional outcomes are evaluated across short-gap (≤15 mm) rodent and long-gap (≥30 mm) large-animal models using motor metrics (Sciatic Functional Index [SFI], compound muscle action potential [CMAP], nerve conduction velocity [NCV]) and, where reported, sensory assessments (von Frey thresholds, two-point discrimination), enabling cross-study benchmarking against quantitative scaffold design-readiness criteria. KEY MESSAGES: Well-designed, cell-seeded conduits consistently achieve ≥85% of motor functional recovery compared to autografts in rodent models of ≤15 mm nerve gaps, with certain platforms nearing equivalence in 20-30 mm defects in large animals; sensory recovery, though less frequently reported, shows parallel trends in studies employing standardized sensory testing. Persistent barriers-including rapid vascularization of long grafts, acidic degradation by-products from synthetic polyesters, mitigation of fibrotic by-products, donor-to-donor cell variability, and scalable good manufacturing practice (GMP)-compliant manufacturing of combination products-remain central to translation. Clinical translation is promising for cell-seeded biodegradable conduits in digital nerve repairs (≤30 mm gaps), with future prospects for obstetric brachial plexus injuries and longer-term horizons for iPSC-based, patient-specific grafts. A next-generation framework integrating optimized biomaterials, function-tuned cells, and advanced fabrication-guided by the quantitative design criteria codified here-will enable predictable, high-quality repair of complex PNIs. .

  PublisherDOI

• Liquid Like Solids: A promising, novel multicompartment diffusion MRI phantom material

  Proceedings on CD-ROM - International Society for Magnetic Resonance in Medicine. Scientific Meeting and Exhibition/Proceedings of the International Society for Magnetic Resonance in Medicine, Scientific Meeting and Exhibition · 2025-09-16

  article

  Motivation: Traditional single-compartment phantoms lack control over pore size, are more indicative of water restriction, and have limited biological relevance. Goal(s): Evaluate liquid-like solids (LLS) as a potential dual-compartment phantom material for dMRI. Approach: LLS phantoms, prepared with different gel concentrations, were imaged with b=0-2500s/mm2 and the signal curves were compared with free water and silica gel, a restricted phantom material. Additionally, several frameworks were evaluated for multi-compartment dependence. Results: LLS phantoms show double-exponential DWI signal decay and gel concentration correspondence with dMRI-estimated volume fraction, with Gaussian and non-Gaussian frameworks showing measurable bias, supporting this material's utility in refining multicompartment models. Impact: Developing biologically relevant multicompartment materials as phantoms can support the advancement of dual tensor and compartment imaging models, allowing innovation and development in more sophisticated diffusion imaging techniques.

  PublisherDOI

• Engineering 3D-printed standalone conductive nerve guides using soft bioinks for peripheral nerve injuries

  Materials Advances · 2025-11-12

  articleOpen accessSenior author

  Conductive nerve guides (CNGs) demonstrate significant regenerative capabilities for bridging critically sized nerve defects due to their unique electrical and mechanical characteristics. However, nerve guides fabricated from conducting polymers through conventional electrochemical methods present challenges, including non-biodegradability and limited customization potential. Here we demonstrate customizable 3D-printed CNGs fabricated using biocompatible bioinks composed of poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and polyvinyl alcohol (PVA) without the need for sacrificial support. The synthesized soft bioinks composed of PEDOT:PSS/20% PVA showed enhanced conductivity, wettability, and shear-thinning behavior. By tailoring the polymer concentration and polymerization conditions, the standalone CNGs, fabricated using extrusion-based 3D printing, were custom-made to match the dimensions of critically sized nerve defects in rodent PNI models. The elimination of sacrificial layers during 3D printing avoids complex post-processing material removal and potential residue-related cytotoxicity. As a result, the 3D-printed CNGs demonstrated excellent biodegradability and biocompatibility. Optimizing soft bioink properties offers a simple manufacturing approach for producing 3D-printed biodegradable and biocompatible CNGs with customizable dimensions. Our findings address the critical need for advanced nerve guide designs tailored to treat peripheral nerve injuries of varying defect sizes.

  PublisherOA PDFDOI

• Advances in modeling permeability and selectivity of the blood-brain barrier using microfluidics

  Microfluidics and Nanofluidics · 2024-06-23 · 4 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• Fabrication of Sodium Trimetaphosphate-Based PEDOT:PSS Conductive Hydrogels

  Gels · 2024-02-01 · 15 citations

  articleOpen accessSenior authorCorresponding

  Conductive hydrogels are highly attractive for biomedical applications due to their ability to mimic the electrophysiological environment of biological tissues. Although conducting polymer polythiophene-poly-(3,4-ethylenedioxythiophene) (PEDOT) and polystyrene sulfonate (PSS) alone exhibit high conductivity, the addition of other chemical compositions could further improve the electrical and mechanical properties of PEDOT:PSS, providing a more promising interface with biological tissues. Here we study the effects of incorporating crosslinking additives, such as glycerol and sodium trimetaphosphate (STMP), in developing interpenetrating PEDOT:PSS-based conductive hydrogels. The addition of glycerol at a low concentration maintained the PEDOT:PSS conductivity with enhanced wettability but decreased the mechanical stiffness. Increasing the concentration of STMP allowed sufficient physical crosslinking with PEDOT:PSS, resulting in improved hydrogel conductivity, wettability, and rheological properties without glycerol. The STMP-based PEDOT:PSS conductive hydrogels also exhibited shear-thinning behaviors, which are potentially favorable for extrusion-based 3D bioprinting applications. We demonstrate an interpenetrating conducting polymer hydrogel with tunable electrical and mechanical properties for cellular interactions and future tissue engineering applications.

  PublisherOA PDFDOI

• Conductive gradient hydrogels allow spatial control of adult stem cell fate

  Journal of Materials Chemistry B · 2024-01-01 · 7 citations

  articleOpen access1st authorCorresponding

  Electrical gradients are fundamental to physiological processes including cell migration, tissue formation, organ development, and response to injury and regeneration. Current electrical modulation of cells is primarily studied under a uniform electrical field. Here we demonstrate the fabrication of conductive gradient hydrogels (CGGs) that display mechanical properties and varying local electrical gradients mimicking physiological conditions. The electrically-stimulated CGGs enhanced human mesenchymal stem cell (hMSC) viability and attachment. Cells on CGGs under electrical stimulation showed a high expression of neural progenitor markers such as Nestin, GFAP, and Sox2. More importantly, CGGs showed cell differentiation toward oligodendrocyte lineage (Oligo2) in the center of the scaffold where the electric field was uniform with a greater intensity, while cells preferred neuronal lineage (NeuN) on the edge of the scaffold on a varying electric field at lower magnitude. Our data suggest that CGGs can serve as a useful platform to study the effects of electrical gradients on stem cells and potentially provide insights on developing new neural engineering applications.

  PublisherOA PDFDOI

• Controlling the Stem Cell Environment Via Conducting Polymer Hydrogels to Enhance Therapeutic Potential

  Advanced Materials Technologies · 2023-02-28 · 15 citations

  article

  Abstract Stem cells are a promising treatment option for various neurological diseases such as stroke, spinal cord injury, and other neurodegenerative disorders. However, the ideal environment to optimize the therapeutic potential of the cells remains poorly understood. Stem cells in the native environment are influenced by a combination of mechanical, chemical, and electrical cues for proliferation and differentiation. Because of their controllable properties, conductive hydrogels are promising biomaterials to interact with stem cells. Herein, this work develops an interpenetrating conducting polymer hydrogel with tunable mechanical properties. The hydrogel serves as a platform to provide mechanical and electrical cues for interactions with mesenchymal stem cells (MSCs). This work optimizes the formulation of the hydrogel for maximum viability of MSCs and relatively higher cytoskeletal protein expression. The viability of cells is not affected due to electrical stimulation (ES). Further, ES alters the trophic factor secretion of MSCs, with significant increase in VEGF pathway genes—VEGFA and HSPB1. In addition, substrate stiffness of the hydrogel enhances the VEGFB secretion compared to control. Hence, the conducting polymer hydrogel system creates a tunable physical and electrical niche to enhance the therapeutic potential of stem cells for neurological injuries.

  PublisherDOI

• Stimulation strategies for electrical and magnetic modulation of cells and tissues

  Cell Regeneration · 2023-07-01 · 20 citations

  reviewOpen accessSenior authorCorresponding

  Electrical phenomena play an important role in numerous biological processes including cellular signaling, early embryogenesis, tissue repair and remodeling, and growth of organisms. Electrical and magnetic effects have been studied on a variety of stimulation strategies and cell types regarding cellular functions and disease treatments. In this review, we discuss recent advances in using three different stimulation strategies, namely electrical stimulation via conductive and piezoelectric materials as well as magnetic stimulation via magnetic materials, to modulate cell and tissue properties. These three strategies offer distinct stimulation routes given specific material characteristics. This review will evaluate material properties and biological response for these stimulation strategies with respect to their potential applications in neural and musculoskeletal research.

  PublisherOA PDFDOI

• Electrical modulation of transplanted stem cells improves functional recovery in a rodent model of stroke

  Nature Communications · 2022-03-15 · 30 citations

  articleOpen access

  Stroke is a leading cause of long-term disability worldwide, intensifying the need for effective recovery therapies. Stem cells are a promising stroke therapeutic, but creating ideal conditions for treatment is essential. Here we developed a conductive polymer system for stem cell delivery and electrical modulation in animals. Using this system, electrical modulation of human stem cell transplants improve functional stroke recovery in rodents. Increased endogenous stem cell production corresponds with improved function. Transcriptome analysis identified stanniocalcin 2 (STC2) as one of the genes most significantly upregulated by electrical stimulation. Lentiviral upregulation and downregulation of STC2 in the transplanted stem cells demonstrate that this glycoprotein is an essential mediator in the functional improvements seen with electrical modulation. Moreover, intraventricular administration of recombinant STC2 post-stroke confers functional benefits. In summation, our conductive polymer system enables electrical modulation of stem cells as a potential method to improve recovery and identify important therapeutic targets.

  PublisherOA PDFDOI

• Electrical stimulation of human neural stem cells via conductive polymer nerve guides enhances peripheral nerve recovery

  Biomaterials · 2021 · 89 citations

  1st authorCorresponding
  • Neuroscience
  • Medicine
  • Cell biology
  PublisherOA PDFDOI

Recent grants

• Enhanced Stem Cell Therapy with Rehabilitation Strategies for Peripheral Nerve Regeneration

  NIH · $196k · 2019–2022

Frequent coauthors

• Paul George

  Stanford Health Care

  23 shared

• Hicham Fenniri

  National Institute for Nanotechnology

  8 shared

• Byeongtaek Oh

  Stanford University

  8 shared

• Thomas J. Webster

  Hebei University of Technology

  8 shared

• Yupeng Chen

  University of Connecticut

  8 shared

• Kelly W. McConnell

  Stanford University

  8 shared

• Alexa Levinson

  Stanford University

  6 shared

• Shuvo Roy

  University of California, San Francisco

  5 shared

Education

• Ph.D, Bioengineering

  University of California Berkeley

  2016

• Ph.D, Bioengineering

  University of California San Francisco

  2016

• B.S, Biomedical Engineering

  Brown University

  2010

Awards & honors

• NIH Director's New Innovator Award (Fall 2025)
• George H. Davis Fellowship (Spring 2025)
• ORAU Ralph E. Powe Junior Faculty Enhancement Award (Summer…
• Career Development Award (Spring 2024)
• American Heart Association New Investigator Award (Spring 20…