Professor Keith Vickerman
Expert in the parasitic protozoa which cause the wasting disease known as sleeping sickness
PROFESSOR KEITH VICKERMAN, who has died aged 83, was a zoologist whose expertise was the study of parasitic protozoa, single-celled organisms, particularly trypanosomes.
Trypanosomes are the causative agents of sleeping sickness, a wasting disease in humans, and nagana in animals, a disease that makes it impossible to farm cattle across a wide swathe of tropical Africa. Vickerman tackled two problems that had puzzled parasitologists for over half a century: how trypanosomes adapt to the environmental changes that occur on transfer from the blood of their mammalian hosts to the completely different conditions in the gut of their tsetse fly vectors – and vice versa; and why it is that, even when the hosts begin to overcome their infections, trypanosomes are never completely eliminated from the blood.
This interest took him, in the early 1960s, to the East African Trypanosomias Research Organisation at Tororo in Uganda and the Nigerian Institute of Trypanosomiasis Research at Jos in Nigeria. Using a combination of cytochemical techniques and electronmicroscopy he discovered that parasites were “preadapted” for the transition from host to vector and back again – a finding that was to become accepted as a general principle applicable to other insecttransmitted protozoa.
Vickerman’s next discovery, for which he would become best known, concerned what has become known as the phenomenon of antigenic variation. Ronald Ross, the discoverer of the mosquito transmission of malaria, had observed that trypanosomes in the blood of patients came in waves and were never completely eliminated from the blood. While examining electronmicrographs of trypanosomes, Vickerman observed that the parasites were enclosed in a thick fuzzy coat, seen by others and dismissed as lacking any significance.
Vickerman discovered that this “coat” was actually a dominant surface antigen that was continually being replaced by an infinite number of different antigenic variants, thus enabling the parasite to keep one step ahead of the immune system.
There were two consequences of this discovery: the realisation that the creation of a vaccine against trypanosomiasis was a virtual impossibility and, much to Vickerman’s surprise, that this phenomenon and its genetic control was to become something of a growth industry for scientists, generating dozens of research papers every year.
Keith Vickerman was born in Huddersfield, Yorkshire, on March 21 1933 and was, from a very early age, fascinated by all aspects of natural history. On one occasion he found a dead cat, brought it home, dissected it and prepared a mounted skeleton with all the bones labelled. Vickerman was educated at St James’s School, Almondbury, Huddersfield, where his biology teacher introduced him to Paul de Kruiff ’s book The Microbe Hunters: he never looked back.
In 1952 Vickerman went to University College London where he read Zoology with parasitology as his special subject, which he studied at King’s College London. It was while he was a student at University College that he attracted the attention of Professor Peter (later Sir Peter) Medawar, who became his mentor, and developed his interest in parasitic protozoa.
His next academic move was as a PhD student to the nascent University of Exeter where he investigated the protozoan parasites of leatherjackets, the larvae of crane flies. This involved spraying lawns with Jeyes fluid and extracting the larvae as they emerged – much to the annoyance of university groundsmen.
In 1958, Vickerman, on Medawar’s initiative, returned as a lecturer to University College where he decided to work on trypanosomes.
In 1968, after his research in Africa, Vickerman moved to Glasgow, as a Reader then Professor of Zoology and in 1984 Regius Professor. He was an exceptionally good and patient teacher, much liked by his postgraduate and undergraduate students. His teaching load at Glasgow was heavy and he continually devised new courses, such as “animal domestication” to keep his students interested.
Vickerman was a hands-on scientist who prepared his own materials and performed his own experiments but liked working alongside others. A Fellow of the Royal Society of Edinburgh, the Royal Society of London and the Academy of Medical Sciences, he won the Royal Society’s Leeuwenhoek medal and the gold medal of the Linnean Society. He was regularly invited to national and international congresses to give lectures and always had something new to say.
A keen gardener, he maintained a very productive and interesting allotment and as president of the Friends of the Glasgow Botanic Gardens, he successfully fought off plans for a building development on the site. He also addressed the Scottish Parliament on the importance of green corridors through cities.
After he retired in 1998 he studied the parasites of the Norway lobster and free living soil protozoa, maintaining his own cultures of protozoa until his last illness.
In 1961 Keith Vickerman married Moira Dutton, who survives him with their daughter, the harpist Louise Vickerman. Professor Keith Vickerman, born March 21 1933, died June 28 2016