Laboratory of Laura A. Smith Callahan, Ph.D.


The Smith Callahan Laboratory focuses on the developing tissue engineering approaches toward clinical treatments for spinal cord injury, traumatic brain injury and cartilage defects using an interdisciplinary approach involving techniques from cell, molecular, and stem cell biology, chemistry, and material science. Utilizing engineering approaches, the laboratory seeks to optimize scaffold design and the expansion of clinically relevant cell sources.

An Assistant Professor in the Department of Neurosurgery, Dr. Smith Callahan earned her doctorate in Biomedical Engineering from the University of Michigan, where her work under focused on the effects of nanofibrous scaffolding on the osteogenic differentiation of embryonic stem cells. Upon completion of her thesis, she was awarded a post-doctoral fellowship on the Regenerative Science T90 training grant which allowed her to further study the effects of nanofibrous scaffolding on the neural differentiation of embryonic stem cells. To obtain additional training in peptide and polymer chemistry and soft material characterization, Dr. Smith Callahan transitioned to a post-doctoral position at the Institute of Polymer Science at the University of Akron with Matthew L. Becker. At the University of Akron, her work focused on the effects of bioactive peptides and gradient hydrogels on stem cell differentiation to mesenchymal and neuronal lineages.

Laura Smith-Callahan


1) Development of multi-component scaffolds to facilitate tissue regeneration through better replication of the native extracellular matrix.

2) Optimization of culture surfaces for the differentiation of human induced pluripotent stem cells to neural stem cells and oligodendrocyte progenitor cells.

3) Identification of optimal artificial matrix properties such as bioactive signaling moiety concentration or mechanical properties using combinatorial approaches.

4) Synthesis of novel biomaterials for spinal cord, brain, and vertebral disk repair.


Hiran Perera, Postdoctoral Research Fellow
Xi (Henry) Lu, Postdoctoral Research Fellow


Office Phone: 713.500.3431


  1. Smith Callahan LA, Ganios AM, McBurney DL, Dilisio MF, Weiner, SD, Horton Jr WE, Becker ML.
    ECM Production of Primary Human and Bovine Chondrocyte in Hybrid PEG Hydrogels Containing Type I Collagen and Hyaluronic Acid. Biomacromolecules. 13(5): 1625-1631, 2012.
  2. Zheng J, Smith Callahan LA, Hao J, Guo K, Wesdemiotis C, Weiss RA, Becker ML. (2012) Strain-Promoted Cross-Linking of PEG-Based Hydrogels via Copper-Free Cycloaddition. ACS Macro Letters. 1:1071-1073, 2012.
  3. Stakleff KS, Lin F, Smith Callahan LA, Wade MB, Esterle A, Miller J, Graham M, Becker ML. Resorbable, Amino acid-based Poly(ester urea)s Crosslinked with Osteogenic Growth Peptide (OGP) with Enhanced Mechanical Properties and Bioactivity. Acta Biomaterialia. 9 (2): 5132–5142, 2013.
  4. Smith Callahan LA, Ganios AM, Childers EP, Weiner, SD, Becker ML. Primary Human Chondrocyte Extracellular Matrix Formation and Phenotype Maintenance using RGD derivatized PEGDM Hydrogels Possessing a Continuous Gradient in Modulus. Acta Biomaterialia. 9 (4): 6095–6104, 2013.
  5. Smith Callahan LA §, Ma Y §, Stafford CM, Becker ML. Concentration Dependent Neural Differentiation and Neurite Extension of mouse ESC on Primary Amine-derivatized Surfaces.Biomaterials Science. 1(5):537-544, 2013. § both authors contributed equally to the work.
  6. Smith Callahan LA, Childers EP, Benard, SL, Weiner, SD, Becker ML. Maximizing Phenotype Constraint and ECM Production in Primary Human Chondrocytes Using RGD Concentration Gradient Hydrogels. Acta Biomaterialia. 9 (7): 7240-7428, 2013.
  7. Smith Callahan LA, Policastro GM, Benard SL, Childers EP, Boettcher RM, Becker ML. Influence of Discrete and Continuous Culture Conditions on Human Mesenchymal Stem Cell Lineage Choice in RGD Concentration Gradient Hydrogels. Biomacromolecules. 14(9): 3047-3054, 2013.
  8. Smith Callahan LA, Xie S, Barker IA, Zheng J, Dove AP, Becker ML. Directed Differentiation and Neurite Extension of mouse Embryonic Stem Cell on Aligned Poly(lactide) Nanofibers Functionalized with YIGSR Peptide. Biomaterials. 34(36): 9089-9095, 2013.
  9. Policastro GM, Lin F, Smith Callahan LA, Esterle A, Graham M, Sloan Stakleff K, Becker ML. OGP Functionalized Phenylalanine-based Poly(ester urea) for Enhancing Osteoinductive Potential of human Mesenchymal Stem Cells. Biomacromolecules. 16 (4): 1358–1371, 2015.
  10. Yang Y-H, Kahn Z, Ma C, Lim HJ, Smith Callahan LA. Optimization of adhesive conditions for neural differentiation of murine embryonic stem cells using hydrogels functionalized with continuous
    Ile-Lys-Val-Ala-Val concentration gradients. Acta Biomaterialia. 21: 55-62, 2015.
  11. Smith Callahan LA. Combinatorial Method/High throughput strategies for hydrogel optimization in tissue engineering applications. Gels. 2: 18, 2016.
  12. Lim HJ, Perera TH, Wilems T, Ghosh S, Zheng YY, Azhdarinia A, Cao Q, Smith Callahan LA.  Response to Di-functionalized Hyaluronic Acid with Orthogonal Chemistry Grafting at Independent Modification Sites in rodent models of neural differentiation and spinal cord injury. Journal of Materials Chemistry B. In press. DOI:  10.1039/C6TB01906D