Borel, Jean-François WORLD OF MICROBIOLOGY AND IMMUNOLOGY84•
in isolating the bacillus that causes pertussis(whooping
cough) in children and later developed a vaccineagainst the
disease. Between 1901 and 1920, Bordet conducted important
studies on the coagulation of blood. When research became
impossible because of the German occupation of Belgium dur-
ing World War I, Bordet devoted himself to the writing of
Traité de l’immunité dans les maladies infectieuses(1920), a
classic book in the field of immunology. He was in the United
States to raise money for new medical facilities for the war-
damaged Free University of Brussels when he received word
that he had been awarded the Nobel Prize. After 1920, he
became interested in bacteriophage, the family of viruses that
kill many types of bacteria, publishing several articles on the
subject. In 1940, Bordet retired from the directorship of the
Pasteur Institute of Brussels and was succeeded by his son,
Paul. Bordet himself continued to take an active interest in the
work of the Institute despite his failing eyesight and a second
German occupation of Belgium during World War II. Many
scientists, friends, and former students gathered in a celebra-
tion of his eightieth birthday at the great hall of the Free
University of Brussels in 1950. He died in Brussels in 1961.See alsoAntibody and antigen; B cells or B lymphocytes;
Bacteria and bacterial infection; Bacteriophage and bacterio-
phage typing; Blood agar, hemolysis, and hemolytic reactions;
Immune system; Immunity; Immunization; T cells or T lym-
phocytesBBorel, Jean FrançoisOREL, JEAN-FRANÇOIS(1933- )
Belgian immunologistJean-François Borel is one of the discoverers of cyclosporin.
The compound is naturally produced by a variety of fungus,
where is acts as an antibiotic to suppress bacterial growth.
Borel’s research in the late 1970s demonstrated that in addi-
tion to the antibiotic activity, cyclosporin could act as an
immunosupressant. This latter property of the compound has
been exploited in limiting the rejection of transplanted organs
in humans.
Borel was born in Antwerp, Belgium. After undergrad-
uate studies in that city, he studied at the Swiss Federal
Institute of Technology in Zurich. He obtained his Ph.D. in
immunogenetics 1964. From there he obtained training in vet-
erinary immunogenetics. In 1965, he moved to the Swiss
Research Institute Department of Medicine where he studied
immunology, particularly the inflammatory response. Five
years later, he joined the scientific staff at Sandoz (now
Novartis). He has been director of the immunology and micro-
biology departments at this company. Since 1983, Borel has
been Vice-President of the Pharma division of Novartis. Since
1981, Borel has also been a professor of immunopharmacol-
ogy in the medical faculty at the University of Bern.
In 1971, Borel isolated a compound (subsequently
called cyclosporin) from a sample of the fungus Beauvaria
niveathat was obtained during a hike by a Sandoz employee
who had vacationed in the United States. Analyses by Borel
showed that, unlike other immunosupressants then known, theisolated compound selectively suppressed the T cellsof the
immune system. The compound was obtained in pure from in- By the end of that decade, Borel had demonstrated the
antirejection powers of the drug in humans.
During this period, Borel is remembered for having
tested the putative immunosupressant drug on himself. The
compound was found to be insoluble. When Borel dissolved
some of the compound in alcohol (subsequently, the use of
olive oil as an emulsifier proved more efficient) and drank it,
the compound subsequently appeared in his blood. This was a
major finding, indicating that the compound might be
amenable to injection so as to control the immune rejection of
transplanted organs.
There has been a controversy as to whether Borel or
another Sandoz scientist (Harold Stähelin) was primarily
responsible for the discovery of cyclosporin. Both were
actively involved at various stages in the purification and test-
ing of the compound, and the primary contribution is difficult
to assign. Nonetheless, it was Borel who first established the
immunosuppressant effect of cyclosporin, during routine test-
ing of compounds isolated from fungifor antibiotic activity.
Beginning in the 1980s, cyclosporin was licensed for
use in transplantations. Since then, hundreds of thousands of
people have successfully received organ transplants, where
none would have before the discovery of cyclosporin.
The research of Borel and his colleagues inspired the
search for other immunosupressant therapies. In recognition of
his fundamental achievement to the advancement of organ
transplantation, Borel received the prestigious Gairdner Award
in 1986.
See alsoAntibody and antigen; Immunosuppressant drugsBORRELIA BURGDORFERI•seeLYME DISEASE
BBotulismOTULISM
Botulism is an illness produced by a toxin that is released by
the soil bacterium Clostridium botulinum. One type of toxin is
also produced by Clostridium baratii. The toxins affect nerves
and can produce paralysis. The paralysis can affect the func-
tioning of organs and tissues that are vital to life.
There are three main kinds of botulism. The first is con-
veyed by food containing the botulism toxin. Contaminated
food can produce the illness after being ingested. Growth of
the bacteriain the food may occur, but is not necessary for
botulism. Just the presence of the toxin is sufficient. Thus, this
form of botulism is a food intoxication (as compared with food
poisoning, where bacterial growthis necessary). The second
way that botulism can be produced is via infection of an open
wound with Clostridium botulinum. Growth of the bacteria in
the wound leads to the production of the toxin, which can dif-
fuse into the bloodstream. The wound mode of toxin entry is
commonly found in intravenous drug abusers. Finally, botu-
lism can occur in young children following the consumptionwomi_B 5/6/03 1:10 PM Page 84