Another Function of the Spleen Discovered

More recently, researchers determined that the spleen is like an elaborate wetlands, a Mississippi bayou for filtering and freshening the blood. In other organs, blood flows through an interconnected mesh of increasingly narrow arteries, veins and capillaries. The spleen, by contrast, has a so-called noncapillary circulatory system: as the blood flows in, it is dumped into puddle-like sinusoids, and to get back out it must squeeze between cells. That dumping and squeezing help filter out blood-borne parasites, aging blood cells too brittle for compression and the little oxidized pellets, the BB’s, with which red blood cells are often pocked. The spleen has often been called a graveyard for red blood cells, but it is more of a recycling center, for the iron and other components are plucked out of the cells and used to stock new hemoglobin cages.

Filtration, cannibalization, and now — serious monocyte cultivation. In the new study, the researchers began by looking at monocytes, the largest of the body’s white blood cells. “It was recognized that these cells are the major repair workers after a heart attack,” Dr. Nahrendorf said. “They remove dead muscle cells, they start rebuilding stable scar tissue, they stimulate the generation of new blood vessels.”

via Basics - Finally, the Spleen Gets Some Respect - NYTimes.com.

Not just for black bile anymore…