An invisible cloak shrouds many cells in our body. The pericellular matrix (PCM) is believed to help protect against viruses, heal wounds and perform other important functions. Yet little is known about this watery coating because it is hard to see and tends to collapse during scientific tests. Pictured is a cartilage cell from a rat, showing the PCM as the dark space between the edge of the cell and the mass of tiny blue plastic beads. In this experiment, scientists used a laser beam to force the beads into the PCM and discovered that it acted like a sieve, with smaller holes nearer the cell surface. This information not only increases our basic understanding of the mysterious cloak but could help determine the optimum size of microcapsules to deliver new generation drugs directly to the surface of cells.
Written by Mick Warwicker
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