Discovery of blood vessel system in bones

A network of very fine blood vessels that connects bone marrow directly with the blood supply of the periosteum that was previously overlooked has now been discovered by Anika Grüneboom, a young researcher who is now working at Universitätsklinikum Erlangen. She made this discovery while working on her doctoral thesis at Universität Duisburg-Essen (UDE) with Matthias Gunzer. Researchers from Universitätsklinikum Essen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) and research institutes in Jena, Berlin, Dresden and Bern were also involved in the study. The group of researchers have now found thousands of previously unknown blood vessels in the bones of mice that traverse perpendicularly across the entire length of the cortical bone. The researchers have named them trans-cortical vessels (TCVs) for this reason. Furthermore, they were able to demonstrate that the majority of both arterial and venous blood flows through this newly discovered system of vessels. This means that the system is a central component for supplying bones with oxygen and nutrients. In addition, the researchers discovered that the newly discovered system of vessels is used by the immune cells in bone marrow to reach the bloodstream. In the case of inflammatory diseases such as arthritis, it is especially important that immune cells reach the source of the inflammation quickly. In future, studies are planned to investigate the role of TCVs for normal bone remodelling and in conditions such as osteoporosis or tumors that metastasize in bones. The research was published Jan. 21, 2019, in Nature Metabolism in an article titled "A network of trans-cortical capillaries as mainstay for blood circulation in long bones."

RA discovery points to new treatment for joint inflammation

Charlottesville, Va.-based researchers at the University of Virginia (UVA) School of Medicine have identified an unexpected contributor to rheumatoid arthritis (RA) that may help explain the painful flare-ups associated with the disease. The discovery points to a potential new treatment for the autoimmune disorder and may also allow the use of a simple blood test to detect people at elevated risk for developing the condition. The promising discovery is among the first to emerge from the School of Medicine's new affiliation with Inova Health, a collaboration that aims to make medical breakthroughs and advance the battle against disease. In this case, the arthritis discovery originated in the lab of the UVA's Kodi Ravichandran, and was facilitated by combining his team's resources and expertise with that of Inova researcher Thomas Conrads, through a THRIV UVA-Inova seed grant. The new findings about RA came in an unexpected fashion. Sanja Arandjelovic, a research scientist in the Ravichandran group, was seeking to better understand what causes the inflammation associated with inflammatory arthritis when she noted that deleting a gene called ELMO1 alleviated arthritis symptoms in mice. This was particularly surprising because Arandjelovic and Ravichandran initially thought that loss of ELMO1 would result in increased inflammation. Digging deeper into the unusual outcome, the researchers determined that ELMO1 promotes inflammation via their function in white blood cells called neutrophils. The researchers also discovered that there is a natural variation in the ELMO1 gene that can prompt neutrophils to become more mobile and have the potential to invade the joints in greater numbers and induce inflammation. Encouragingly, blocking ELMO1 in lab mice alleviated arthritis inflammation without causing other problems, Ravichandran noted. His laboratory is now seeking to identify drugs that could inhibit the function of ELMO1 and is also designing a test for the variation in the ELMO1 gene. The research was published in Nature Immunology.

Ortho RTI initiates pivotal study on Ortho-R for rotator cuff repair

Ortho Regenerative Technologies Inc., a Kirkland, Quebec-based orthopedic and sports medicine technology company, reported the initiation of a six-month pivotal animal study on Ortho-R for rotator cuff repair. In addition, a pre-IND (Investigational New Drug) meeting is to be held later this month with the U.S. FDA to formalize the requirements for the filing of its application to commence human trials on Ortho-R. "The pivotal study is designed and powered to show statistically significant healing for rotator cuff repair by way of MRI and Histopathology. The first series of MRI results will be available after three months and are expected to confirm our previous findings where we showed superior healing over standard of care. The study is also designed to assess whether the repair could be accelerated or further improved with a higher dose of Ortho-R," said the company's chief scientific officer, Michael Buschmann. The company recently compiled and submitted documents for a formal pre-IND submission meeting with the FDA. The purpose of the meeting is to discuss moving Ortho-R into the clinic for human testing. The results of this pivotal study on Ortho-R are intended to augment the IND package with more information on the ideal dosage to take forward into patients.