Hay fever is one of the most common allergic conditions. Some 10 million people in England alone are estimated to be affected by the allergic reactions caused when pollen enters the respiratory airways, with grass pollen in particular being the source of much suffering between the months of May and August. As many as one in five people will be affected by hay fever at some point in their lives.
The link between hay fever and pollen was established as long ago as the end of the 19th Century, and the term “allergy” itself was only coined in 1906. Some years later, a scientist at St Mary’s Hospital in London built on this knowledge to devise a kind of immunotherapy treatment based on exposure to small amounts of grass pollen.
In 1911, Leonard Noon published his first work on the revolutionary treatment involving injecting pollen “toxin” under the skin of hay fever sufferers. The toxin was in fact an extract of grass pollen which Noon believed could induce a state of immunity to hay fever. Long before antiallergenic drugs were developed, Noon demonstrated that prophylactic subcutaneous inoculation with grass pollen was effective in suppressing immediate conjunctival sensitivity – watery eyes – to grass pollen. He and his colleague John Freeman, who continued Noon’s work after his premature death in 1913 at the age of 35 from pulmonary tuberculosis, were the first to demonstrate that it was possible to induce a kind of immunotherapy by suppressing a person’s sensitivity to grass pollen. Following therapy involving the administration of very low doses of grass pollen given by skin injections at intervals of 3 to 4 days, the scientists noted a marked improvement in hay fever symptoms.
William Frankland, a colleague of Freeman’s at St Mary’s later performed the first controlled clinical trial of grass pollen immunotherapy in 1954, by comparing grass pollen extract and the partially purified pollen proteins, with ultrafiltrate that contained no grass pollen proteins. Frankland’s work established a firm scientific foundation for the practice of allergen immunotherapy – a lasting legacy of Noon’s pioneering work.