Department of Orthopaedic Surgery

Peter G Alexander, PhD

  • Assistant Professor

Education & Training

  • Research Fellowship – Osteoarthritis Section, NIAMS, NIH, Bethesda, MD
  • Postdoctoral training – Cartilage Section, NIAMS, NIH, Bethesda, MD
  • PhD – Developmental Biology and Teratology, Thomas Jefferson University, Philadelphia, PA
  • BS/BA - Biology/Studio Art, Wake Forest University, Winston-Salem, NC

Representative Publications

  1.  Alexander PG, Tuan RS. Carbon monoxide-induced axial skeletal dysmorphogenesis in the chick embryo. Teratology 2003 Apr; 67(4):219-30.
  2. Tuli R, Tuli S, Nandi S, Wang ML, Alexander PG, Haleem-Smith H, Hozack WJ, Manner PA, Danielson KG, Tuan RS. Characterization of multipotential mesenchymal progenitor cells derived from human trabecular bone. Stem Cells 2003; 21:681-693.
  3. Alexander, PG, Chau, LC, Tuan, RS. Role of nitrogen species in chick embryonic organogenesis and dysmorphogenesis. Birth Defects Res, Part A. 2007; 79: 581-594.
  4. Alexander PG, McCarron JA, Levine MJ,, Melvin GM, Murray P, Manner PA, Tuan RS. An in vivo Lapine Model for Impact-Induced Injury and Osteoarthritic Degeneration of Articular Cartilage.  Cartilage. 2012; 3:323-333
  5. Alexander PG, Song Y, Taboas J, Chen FH, Levin MJ, McCarron JA, Melvin GM, Manner PA, Tuan RS.  Development of a Spring-loaded Impact Device to Deliver Injurious Mechanical Impact to Articular Cartilage Surface. Cartilage. 2013; 4:52-62
  6. Lin H, Zhang D, Alexander PG, Yang G, Tan J, Cheng AW, Tuan RS.  Application of visible light-based projection stereolithography for live cell-scaffold fabrication with designed architecture. Biomaterials. 2013; 34(2):331-9.
  7. Jackson WM, Alexander PG, Bulken-Hoover JD, Vogler JA, Ji Y, McKay P, Nesti LJ, Tuan RS.  Mesenchymal progenitor cells derived from traumatized muscle enhance neurite growth. J Tissue Eng Regen Med. 2013; 7(6):443-451.
  8. Yang G, Rothrauff BB, Lin H, Gottardi R, Alexander PG, Tuan RS.   Enhancement of tenogenic differentiation of human adipose stem cells by tendon-drived extracellular matrix.  Biomaterials. 2013; 34(37):9295-306.
  9. Bobick BE, Alexander PG, Tuan RS. High efficiency transfection of embryonic limb mesenchyme with plasmid DNA using square wave pulse electroporation and sucrose buffer.  Biotechniques. 2014; 56(2):85-89.
  10. Lin H, Cheng AW, Alexander PG, Beck AM, Tuan RS.  Cartilage tissue engineering application of injectable gelatin hydrogel with in situ visible-light-activated gelation capability in both air and aqueous solution. Tissue Eng Part A. 2014; 20(17-18):2402-11.
  11. Lin H, Lozito TP, Alexander PG, Gottardi R, Tuan RS. Stem cell-based microphysiological osteochondral system to model tissue response to interleukin-1β. Mol Pharm. 2014; 11(7):2203-12.
  12. Xie X, Ulici V, Alexander PG, Jiang Y, Zhang C, Tuan RS.  Platelet-rich plasma inhibits mechanically induced injury in chondrocytes. J Arthroscopy. 2015; 31(6):1142-50.
  13. Bonnevie ED, Delco M, Forier LA, Alexander PG, Tuan RS, Bonassar LJ.  Characterization of Tissue Response to Impact Loads Delivered Using a Hand-Held Instrument for Studying Articular Cartilage Injury. Cartilage. 2015; 6(4): 226-232.
  14. He J, Jiang Y, Alexander PG, Ulici V, Zhu Y, Wu S, Tuan RS. Infrapatellar fat pad aggravates degeneration of acute traumatized cartilage: a possible role for interleukin-6. Osteoarthritis Cartilage. 2016 Sep 9. pii: S1063-4584(16)30266-7. doi: 10.1016/j.joca.2016.09.001
  15. Rothrauff BB, Shimomura K, Gottardi R, Alexander PG, Tuan RS. Anatomical region-dependent enhancement of 3-dimensional chondrogenic differentiation of human mesenchymal stem cells by soluble meniscus extracellular matrix. Acta Biomater. 2016 Nov 19. pii: S1742-7061(16)30642-0. doi: 10.1016/j.actbio.2016.11.046.

Research Interests

I am interested in the pathogenesis of skeletal tissue injury and degeneration and cell and material-based repair of these same tissues. I explore cell-based mechanisms of these with a focus on the stem cell either as a participant or mediator of regenerative processes. I employ a range of techniques from in vitro systems to animal models. In the last 5 years, we have been :

  1. Developing in vivo models to study mechanisms of heterotopic ossification following blast trauma and osteomyelitis;
  2. Testing scaffolds and drug/gene delivery systems for cartilage, tendon, meniscus and nerve repair; and
  3. Custom-designing bioreactors to model cell specific cell and tissue interactions that may be used to:
  • Study musculoskeletal development and disease,
  • Serve as bioreactors for fabrication of cell-based mature, functional tissue-engineered implants
  • Test drug efficacy and environmental toxicity.

These include multi-tissue models to study embryonic limb development, chronic inflammation and OA, metastatic bone disease, among others.

I thoroughly enjoy the interdisciplinary nature of the research and environment here at the University of Pittsburgh.

Link to Lab:  Center for Cellular and Molelcular Engineering



Patent title: A Modular, Micrfluidic, Mechanically Active Bioreactor for 3D, Multi-tissue, Tissue Culture. Application No.:  61/868,979. Pitt Ref. No.: 03088. Attorney Ref. No.: 8123-91538-01

Patent Title: Treating Soft Tissue via Controlled Drug Release. Application No. 61/949,886, Pitt Ref. No. 03248. Attorney Ref. No.: 8123-92685-01

Patent Title: Microfluidic Tissue Development Systems. Pitt Ref. No.: 03707. Application No. Attorney Ref. No: 8123-95870-02


Collaborators (internal and external)

Internal: Hang Lin, Riccardo Gottardi, Haruyo Yagi, Rebecca Watters, Kurt Weiss, Steffi Oesterreich, Larry Vernetti, Sunghwan Kim,

External: Xuetau Xie, Lisa Fortier, Larry Bonasser, Phil Samson, Shane Hutson, John Wikswo, Harihana Baskaran, Richard Samosa,

Research Grants

1.   ​Regenerative Repair of Traumatic Articular Cartilage Injuries:  Point-of-Care Application of Mesenchymal Stem Cells and Chondrocytes

Granting Organization: DoD
Period Of Support: 12/1/14 – 11/30/18   
Role: Co-I

2.   Customized Fabrication of Osteochondral Tissue for Articular Joint Surface Repair

Granting Organization: DoD
Period of Support: 8/25/14 – 8/24/17   
Role: Key Personnel

3.   Vanderbilt-Pittsburgh Resource for Organotypic Models for Predictive Toxicology (VPROMPT)

Granting Organization: EPA
Period of Support: 12/1/14 – 11/30/18  
Role: Key Personnel

4.   Cell-Based Meniscal Repair Using an Aligned Bioactive Nanofibrous Sheath

Granting Organization: DoD
Period of Support: 6/15/15 - 12/14/17
Role: Co-I

5.   Adult Stem Cell-Based Enhancement of Nerve Conduit for Peripheral Nerve Repair

Granting Organization: DoD
Period of Support: 9/30/15 – 9/29/18
Role: Co-I

6.   A Microphysiological 3D Organotypic Culture System for Studying Degradation and Repair of Composite Skeletal Tissues in Microgravity Environment

Granting Organization: CASIS
Period of Support: 4/30/2016 – 12/31/2017
Role: Co-I