Serious allergic reactions can be life-threatening and are known as anaphylaxis, a word invented by the French scientist Charles Richet (inset), who won the Nobel Prize for Medicine 100 years ago. He discovered that a single dose of an allergen could permanently change body chemistry, causing sensitivity to repeat doses, even in tiny amounts. We now understand why this happens - pictured is a mast cell, part of our body’s immune armoury, which has become primed by antibodies after mistaking an allergen for invading germs. A repeat encounter has triggered the cell to release histamine, stained pink, which counters bacteria and viruses but in excessive quantities causes capillaries to leak, tissues to swell and blood pressure to fall. Since 1913, many anti-allergic drugs have derived from Richet’s pioneering research – an achievement not to be sneezed at!
Written by Mick Warwicker
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