Serum-separating tube Serum-separating tube Serum-separating tubes, also known as serum separator tubes or SSTs, are used in medical clinical chemistry tests requiring blood serum. SSTs are sometimes called "marble-top tubes," "tiger-tops," or "gold-topped tubes", referring to the stoppers which are either gold, red with a gold ring on top, or marbled red and grey. Marble-top tubes are also referred to as "tiger-tops" in some clinics. SPS tubes have a paler colour, sometimes leading confusion; these are known as "yellow tops" not "gold". Trademarked versions include Covidien "Corvac" tubes. They contain a special gel that separates blood cells from serum, as well as
Angiocrine growth factors Angiocrine growth factors Angiocrine growth factors are molecules found in blood vessels' endothelial cells that can stimulate organ-specific repair activities in damaged or diseased organs. Endothelial cells possess tissue-specific genes that code for unique growth factors, adhesion molecules and factors regulating metabolism. The discovery emerged after the entirety of active genes in endothelial cells was decoded, resulting in an atlas of organ-specific blood vessel cells. The atlas documented hundreds of already-known genes that had never been associated with these cells. Organs dictate the structure and function of their own blood vessels, including the repair molecules they secrete. Each organ produces