STEM CELLS AND CRANIOFACIAL TISSUE ENGINEERING LAB

Current Projects:

Modulation of stem cells differentiation potentials for tissue engineering

Tissue engineering is an interdisciplinary subject area of biotechnology aimed at solving critical medical problems involving tissue defects and organ failures. The target is to produce complete, living tissue substitute materials in order to maintain, restore and improve biological functions of tissues/organs. Multipotent mesenchymal stem cells (MSCs) isolated from patients bone marrow and adipose tissue are capable of differentiating into osteoblasts, adipocytes, chondrocytes, neurons, myocytes, and tenocytes which can be used for engineering different types of tissues for clinical treatments. However, different characteristics of patients will cause diverse capacities of cell proliferation rate and differentiation potentials. Modulation of the stem cells in order to optimize their function for tissue regeneration plays a critical role in successful clinical application. We have successfully isolated multiple potential stem cells from human and animal fat tissue and engineered bone, cartilage, and adipose tissues in vitro and in vivo. Also, we have demonstrated that the differentiation potentials of the stem cells can be improved using sexual steroids.

Cell-based therapy for craniosynostosis

Craniosynostosis is a disorder characterized by premature suture fusion before completion of brain growth. Dura mater plays an important role in morphogenesis and phenotypic maintenance of cranial sutures and calvarial bone formation. Identification of dura mater and cranial suture cell phenotype will be extremely useful in tissue engineering of cranial suture for the patients suffering from craniosynostosis and engineer autologous cell-based dura substitutes. Our lab found stem cells with multiple differentiation potentials within dura mater and cranial suture tissues. These cells were able to undergo osteogenic, chondrogenic, and adipogenic differentiation under specific stimulations.

Non-invasive monitoring of growth and development of tissue engineered products

Magnetic resonance microscope (MRM) is a noninvasive imaging technique with high spatial resolution, excellent soft-tissue contrast, and full three-dimensional capabilities. MRM provides information from living systems such as cell growth and distribution, cell volume, distribution of oxygen, and cell metabolism, which is not available from other techniques. Our lab demonstrated that high resolution MRM is able to monitor osteogenesis of tissue engineered constructs prepared by human bone marrow MSCs seeded on biodegradable scaffolds. The characteristics of MR images correlated well with biochemical progression of osteogenic differentiated constructs, which indicates MR can serve as a promising, non-invasive monitoring system to provide 3-dimensional information for growth and development of TE structures.

Peer reviewed publications

1. Ioana A. Peptan, Liu Hong, and Carla A. Evans. Multiple differentiation potentials of neonatal dura mater-derived cells. Cell and Tissue Research (under review)
2. Liu Hong, Ioana A. Peptan, Aylin Colpan, Joseph Daw: Adipose tissue engineering by human fat-derived stromal cells. Plastic and Reconstructive Surgery (under review)
3. Liu Hong, Ioana A. Peptan, Huihui Xu, Richard Magin. Evaluation of osteogenic differentiation of tissue engineered constructs by magnetic resonance microscopy. Journal of Orthopedic Research (accepted).
4. Huihui Xu, Shadi F. Othman, Liu Hong, Ioana A. Peptan, and Richard L. Magin. Magnetic Resonance Microscopy for Monitoring Osteogenesis in Tissue-Engineered Construct in vitro. Physics in Medicine and Biology (accepted)
5. Ioana A. Peptan, Liu Hong, Huihui Xu, Richard Magin. MR assessment of osteogenic differentiation of tissue-engineered constructs. Tissue Engineering (accepted)
6. Peptan Ioana, Liu Hong, Jeremy Mao. Comparison of osteogenic potentials of visceral and subcutaneous adipose-derived cells of rabbits. Plastic and Reconstructive Surgery. (accepted )
7. Liu Hong, Ioana Peptan, Paul Clark, Jeremy Mao. Ex vivo adipose tissue engineering by human mesenchymal stem cell seeded gelatin sponge. Annual of Biomedical Engineering . 2005 Apr;33(4):511-7.