Department of Molecular and Cellular Medicine
142 Reynolds Medical Building
College Station, Texas 77843
Education and Post-Graduate Training
Endothelial invasion in 3D matrices
The mechanism through which primary human endothelial cells invade into 3D matrices is being studied. The model used mimics angiogenesis, or the process of new blood vessel formation from existing structures (see Figure 1)
Angiogenesis is critical for successful pregnancy and abnormally stimulated during tumor growth, rheumatoid arthritis and blinding eye diseases such as diabetic retinopathy, retinopathy of prematurity and macular degeneration.
Intracellular molecular signals that are responsible for endothelial invasion responses are being investigated; along with important surface molecules include membrane-associated matrix metalloproteinases and integrins. We are utilizing pharmacological, gene knockdown, gene expression and protein localization studies to confirm the involvement of all molecules identified in preliminary screening experiments.
Extracellular matrix biology
Collaborative studies with Dr. Alvin Yeh's laboratory (Texas A&M University, Department of Biomedical Engineering) have revealed details about communication between invading endothelial cells and their surrounding 3D collagen matrix (see Figure 2). In these studies, two photon fluroescence was used to detect fluorescently-labeled endothelial cells as well as the surrounding collagen matrix using second harmonic generation (SHG). These studies combined with biochemical analyses are expected to provide further insight into molecular signals that regulate endothelial cell interactions with the extracellular fibrous collagen matrix as they form multicellular sprouting structures that contain lumens.
Specialty Training/Board Certifications
Bayless, K.J., and Davis, G.E. (2003) Sphingosine-1-phosphate markedly induces matrix metalloproteinase and integrin-dependent human endothelial cell invasion and lumen formation in three-dimensional collagen and fibrin matrices. Biochem. Biophys. Res. Commun., 312: 903-913.
Bayless, K.J., and Davis, G.E. (2004) Microtubule depolymerizing agents rapidly collapse capillary tube networks in vitro and angiogenic vessels in vivo through the small GTPase Rho. J. Biol. Chem., 279: 11686-11695.
Su, S.C., Mendoza, E.A., Kwak, H.I., and Bayless, K.J. (2008) Molecular profile of endothelial invasion of three-dimensional collagen matrices: insights into angiogenic sprout induction in wound healing. Am. J. Physiol. Cell Physiol., 295(5): C1215-1229.
Kang, H., Bayless, K.J., and Kaunas, R. (2008). Fluid shear stress modulates endothelial cell invasion into three-dimensional collagen matrices. Am. J. Physiol. Heart Circ. Physiol.; 295(5): H2087-2097.
Lee, P.F., Yeh, A.T., and Bayless, K.J. (2009) Nonlinear optical microscopy reveals invading endothelial cells anisotropically alter three-dimensional collagen matrices. Exp. Cell Res., 315(3): 396-410.
Burghardt, R.C., Burghardt, J.R., Taylor, J.D., 2nd, Reeder, A.T., Nguen, B.T., Spencer, T.E., Bayless, K.J., and Johnson, G.A. (2009) Enhanced focal adhesion assembly reflects increased mechanosensation and mechanotransduction at maternal-conceptus interface and uterine wall during ovine pregnancy. Reproduction; 137(3): 567-582.