John Hermon-Taylor, who has died on his 85th birthday, was a surgeon who was greatly distressed by the devastating surgery which he had to perform on patients with Crohn’s disease (CD), a long-term chronic inflammatory illness affecting the intestine, and was determined to find a better way of managing it.
Although there is a strong genetic component to CD, the underlying cause is not known. However, there have long been known to be similarities between CD and Johne’s disease in cattle which is caused by the Mycobacterium avium subspecies paratuberculosis (MAP).
Hermon-Taylor was the first to demonstrate a specific DNA repetitive sequence called IS900 in MAP, and in 1990 began a study which revealed the presence of MAP DNA in about two-thirds of people with Crohn’s disease using a test for IS900 that has become the cornerstone of detection.
In 1996 he and colleagues showed that MAP can be found alive in pasteurised milk and he went on, in 2000, to hypothesise that in people with a genetic susceptibility, the bacterium might cause the body to trigger an inappropriate chronic inflammatory response, causing CD.
In 2005 he reported that China, which has seen significant expansion of its dairy industry and milk consumption, had experienced a simultaneous rise in the incidence of CD.
Although in recent years the outlook for CD has improved considerably with the advent of drugs capable of suppressing the immune response, many clinicians and immunologists remain sceptical about a link between CD and MAP. Hermon-Taylor, however, was tireless in pressing the case for the use of drugs active against MAP to treat the disease and became passionate in recent years about developing a therapeutic vaccine.
Working with Sarah (now Dame Sarah) Gilbert at Oxford and Tim Bull at St George’s Hospital, Tooting, between 1997 and 2007 he developed a potential vaccine which has been trialled in cattle and proved effective in inducing an immune response against MAP.
In the days before Hermon-Taylor’s death the first human patient was enrolled in a “proof of concept” study of the vaccine. Although debilitated from the effects of a stroke his eyes lit up when given this news by his daughter.
John Hermon-Taylor was born on October 16 1936, the second of five children of Hermon Taylor, a surgeon at St Bartholomew’s Hospital who produced the first flexible gastroscope, and his wife Maerie, a medical secretary.
From Harrow School, where he was a scholar he read Medicine at St John’s College, Cambridge, and trained at the London Hospital, qualifying in 1960. He trained as a surgeon, being awarded the Hallett Prize for the top mark in the MRCS exam, and in 1968 spent a year at the Mayo Clinic as an MRC Travelling Fellow.
In 1976 he was appointed as Professor of Surgery at St George’s Hospital where he remained until retirement in 2002. He then continued his academic work in collaboration with Professor Jeremy Sanderson at King’s College, London, until his final illness. Other research interests included diseases of the pancreas, enzyme activation in gastric disorders and the epidemiology of breast cancer.
Possessed of sparking blue eyes under bushy eyebrows, Hermon-Taylor had an endlessly curious mind, read voraciously and was always genuinely interested in other people’s hopes and ambitions: “Write your ticket and go and get it” was his advice.
He was a keen and adventurous traveller, fisherman, walker, sailor and gardener Rugby was a passion, as was history: he was knowledgeable about the Napoleonic wars and Second World War aeroplanes. On his 81st birthday he achieved his dream of a flight in a Spitfire.
In 1971 he married Ellie, whom he had met at the Mayo Clinic where she was working as a biologist. She survives him with their son and daughter.
John Hermon-Taylor, born October 16 1936, died October 16 2021