In a recent report that was published in Microvascular Research http://www.ncbi.nlm.nih.gov/pubmed/20709086 (ePub ahead of print), we have revealed a key relationship between the control of microvascular pericyte shape, contractility and mechanical stiffness. The work points to the pivotal role that the neutral cysteine protease family member, calpain I, is likely to be playing in modulating pericyte adhesion and signaling (to/through the basement membrane and onto the capillary endothelium). We postulate that these mechano-chemical signaling networks that originate within pericyte cytoplasm and the plasma membrane-cytoskeletal interface are likely to orchestrate capillary dynamics during physiologic or, possibly, pathologic angiogenesis.
Posted on: Tuesday, 15 June 2010, 09:35 CDT
Cell contractions may be key to initiating new blood-vessel growth near tumors.
Cancer researchers have been studying angiogenesis — the growth of new blood vessels — since the early 1970s, when Judah Folkman first theorized that tumors could be destroyed by cutting off their blood supply.
For most of that time, scientists have focused on the biochemical signals that promote angiogenesis, in hopes of finding drugs that can starve tumors by blocking their ability to release the proteins that promote vessel growth. More recently, a few scientists have taken a new approach: studying how contractions in nearby cells can stimulate angiogenesis.
Krystyn Van Vliet, associate professor of materials science and engineering at MIT, and researchers at Tufts University recently showed that cells called pericytes, which surround small blood vessels, generate contractions that could serve as a mechanical signal to initiate angiogenesis. “Up to now, people have assumed that the role of pericytes was biochemical in nature,” says Van Vliet.
Pinpointing the role of those mechanical signals could help researchers develop drugs that either promote angiogenesis to enhance wound healing or suppress the harmful angiogenesis that leads to tumor growth or vision loss (in age-related macular degeneration or diabetes-induced retinal damage), says Ira Herman, a professor of physiology at Tufts University School of Medicine and expert in pericyte cell biology who collaborated with Van Vliet on this study.
BOSTON and CAMBRIDGE (April 26, 2010) — Pericytes, the contractile cells surrounding capillaries, may use mechanical forces to initiate angiogenesis, the “sprouting” of new blood vessels, according to researchers at Tufts University School of Medicine (TUSM) and the Massachusetts Institute of Technology (MIT). The study, published in Journal of Physics: Condensed Matter, is among the first to examine mechanical signaling by pericytes as a potential driver of angiogenesis, which is crucial in the progression of cancer, diabetic retinopathy, and age-related macular degeneration.
The TIWR has just published a study focused on creating biodegradable vascularized microfluidic networks in silk fibroin. Authors include Jeffrey Borenstein, Katie Megley, Kim Wall, Eleanor Pritchard, David Truong, David Kaplan, Sarah Tao, and Ira Herman. These integrated vascular networks will sustain living human skin equivalents for personalized regenerative medicine and wound healing. Here’s the link http://www.mdpi.com/1996-1944/3/3/1833/
Ira M. Herman, Ph.D. TIWR Director
Welcome to The Tufts Center for Innovations in Wound Healing Research (TIWR) at Tufts University School of Medicine. We launched TIWR in 2006, after recognizing that significant advances in our understanding the biology of wound healing had yet to be fully exploited in the technologies that are currently available for patient or combat casualty care.
Our group includes basic science and clinical investigators at Tufts University united with colleagues from partnering institutions. This multi-investigator and cross-disciplinary regenerative medicine- and wound healing-based initiative combines expertise in epithelial cell and extracellular matrix biology, the angiogenesis of wound healing, stem cell biology, and the cellular biology of wound healing/tissue regeneration. TIWR investigators and clinician scientists are now leveraging their expertise in regenerative medicine and wound repair science with cutting-edge technologies in biomaterials sciences and nano-fabrication processing to create innovative, personalized wound healing therapeutics, including ‘next-generation’ wound care products for civilian or soldier use.
We have several projects underway. Find out more about TIWR, our research, our partners and our mission, by clicking through this website, and please feel free to contact us with comments or questions. Thanks, Ira