Waleed O. Twal , Ph.D.
Research Assistant Professor
Room 653, Basic Science Building
Office: (843) 792-5483
Lab: (843) 792-7054
BS Animal Science University of Jordan 1977
MS Animal Science University of Tennessee 1988
PhD Physiology Pennsylvania State University 1993
Member of the Argraves Laboratory. One of my primary scientific interests is extracellular matrix (ECM) biology. Currently I am working on determining the function of the extracellular matrix protein fibulin-1. I have found that fibulin-1 inhibits the adhesion, spreading and migration of certain types of cancer cells and also transformed cell lines. However, fibulin-1 has no effect on primary cultured cell line such as fibroblasts and endothelial cells. I am interested in exploring the use of fibulin-1 as an anti-metastatic agent. The ultimate goal of this research is to design drugs based on fibulin-1 that can be used to prevent primary cancers from spreading to other sites in the body. Since fibulin-1 is expressed during embryonic development at sites of epithelial to mesenchymal transition, we now explore its role in the morphogenesis of the heart valves and septa that arise from such transitions.
Another area of research that I am interested in is angiogensis. I have worked on the role of bFGF in endochondrial bone formation. I have isolated endothelial cells from chicken fat pads and also purified bFGF from chicken cartilage and localized bFGF to proliferative and hypertrophic zones of the epiphyseal growth plate. Recently it has been found that mutations in FGF receptors cause certain type of dysplasia in humans. Another aspect of the angiogenesis research that I am involved in is the role of the LDL receptor related protein (LRP-1) in modulation of behavior of smooth muscle and endothelial cells. We have shown that antagonism of receptor function leads to an increase in proliferation of smooth muscle cells and fibroblasts. This effect is mediated by increased levels of thrombospondin.
Another area of research I am working on is the function of the newly discovered HDL receptor, Cubilin, in mediating uptake, degradation and transcytosis of HDL. Work in the lab is currently directed toward determining the physiological significance of cubilin-mediated HDL uptake in tissues such as the renal proximal tubule and yolk sac endoderm.
- Twal, W. O., S. C. Klatt, K. Harikrishnan, E. Gerges, M. A. Cooley, T. C. Trusk, B. Zhou, M. G. Gabr, T. Shazly, S. M. Lessner, R. R. Markwald and W. S. Argraves. "Cellularized Microcarriers as Adhesive Building Blocks for Fabrication of Tubular Tissue Constructs." Ann Biomed Eng, (2013) [PMID: 23943070]
- Mainous, A. G., 3rd, R. U. Wright, M. M. Hulihan, W. O. Twal, C. E. McLaren, V. A. Diaz, G. D. McLaren, W. S. Argraves and A. M. Grant. "Telomere Length and Elevated Iron: The Influence of Phenotype and Hfe Genotype." Am J Hematol 88, no. 6 (2013): 492-6 [PMID: 23512844]
- Hartwell, K. J., M. M. Moran-Santa Maria, W. O. Twal, S. Shaftman, S. M. DeSantis, A. L. McRae-Clark and K. T. Brady. "Association of Elevated Cytokines with Childhood Adversity in a Sample of Healthy Adults." J Psychiatr Res 47, no. 5 (2013): 604-10 [PMID: 23415658]
- Al Gadban, M. M., J. German, J. P. Truman, F. Soodavar, E. C. Riemer, W. O. Twal, K. J. Smith, D. Heller, A. F. Hofbauer, J. C. Oates and S. M. Hammad. "Lack of Nitric Oxide Synthases Increases Lipoprotein Immune Complex Deposition in the Aorta and Elevates Plasma Sphingolipid Levels in Lupus." Cell Immunol 276, no. 1-2 (2012): 42-51 [PMID: 22560558]
- Gooz, P., Y. Dang, S. Higashiyama, W. O. Twal, C. J. Haycraft and M. Gooz. "A Disintegrin and Metalloenzyme (Adam) 17 Activation Is Regulated by Alpha5beta1 Integrin in Kidney Mesangial Cells." PLoS One 7, no. 3 (2012): e33350 [PMID: 22413019]
- Cooley, M. A., V. M. Fresco, M. E. Dorlon, W. O. Twal, N. V. Lee, J. L. Barth, C. B. Kern, M. L. Iruela-Arispe and W. S. Argraves. "Fibulin-1 Is Required During Cardiac Ventricular Morphogenesis for Versican Cleavage, Suppression of Erbb2 and Erk1/2 Activation, and to Attenuate Trabecular Cardiomyocyte Proliferation." Dev Dyn 241, no. 2 (2012): 303-14 [PMID: 22183742]
- Cangemi, C., V. Skov, M. K. Poulsen, J. Funder, W. O. Twal, M. A. Gall, V. Hjortdal, M. L. Jespersen, T. A. Kruse, J. Aagard, H. H. Parving, S. Knudsen, P. F. Hoilund-Carlsen, P. Rossing, J. E. Henriksen, W. S. Argraves and L. M. Rasmussen. "Fibulin-1 Is a Marker for Arterial Extracellular Matrix Alterations in Type 2 Diabetes." Clin Chem 57, no. 11 (2011): 1556-65 [PMID: 21926180]
- Szabo, A., R. Unnep, E. Mehes, W. O. Twal, W. S. Argraves, Y. Cao and A. Czirok. "Collective Cell Motion in Endothelial Monolayers." Phys Biol 7, no. 4 (2010): 046007 [PMID: 21076204]
- Al Gadban, M. M., K. J. Smith, F. Soodavar, C. Piansay, C. Chassereau, W. O. Twal, R. L. Klein, G. Virella, M. F. Lopes-Virella and S. M. Hammad. "Differential Trafficking of Oxidized Ldl and Oxidized Ldl Immune Complexes in Macrophages: Impact on Oxidative Stress." PLoS One 5, no. 9 (2010) [PMID: 20824093]
- Smith, K. J., W. O. Twal, F. Soodavar, G. Virella, M. F. Lopes-Virella and S. M. Hammad. "Heat Shock Protein 70b' (Hsp70b') Expression and Release in Response to Human Oxidized Low Density Lipoprotein Immune Complexes in Macrophages." J Biol Chem 285, no. 21 (2010): 15985-93 [PMID: 20348092]
- Argraves, W. S., A. Tanaka, E. P. Smith, W. O. Twal, K. M. Argraves, D. Fan and C. C. Haudenschild. "Fibulin-1 and Fibrinogen in Human Atherosclerotic Lesions." Histochem Cell Biol 132, no. 5 (2009): 559-65 [PMID: 19693531]