Research and Studies
Each student at Oxford negotiated
with his tutor a program of study, which included the level of
standard to which the student would be held. Standards could be
set low enough to allow students to focus on partying and social
life (a "pass" degree) or set as high as to require
high scores on rigorous examinations (leading to a degree labeled
First, Second, or Third).
Peter Medawar graduated
with a First. Because his interest was well kindled in zoology,
he stayed on as a graduate student at Oxford. He plunged into
research on embryos, using the then revolutionary technique of
culturing cells. His first studies identified a compound in malt
extract that inhibited connective tissue cells in culture. He
showed the first draft of his manuscript describing the research
to Howard Florey, the discoverer of penicillin. Florey pulled
no punches in denouncing the paper, saying that "it sounds
more like philosophy than science." Despite the criticism,
Florey encouraged him to fix the paper and to pursue his line
of research, putting him in touch with chemists with whom he could
consult to learn more about the mysterious inhibitory compound.
Peter never identified the chemical nature of this compound. In
the meantime, he did use the malt extract to study the mathematics
that describe growth of cell in culture.
conducting his research, Peter also worked in Florey's laboratory,
where everyone studied wound and burn healing to aid in the World
War II effort in Britain. At that time, people with severe burns
were kept alive with blood transfusions and sulfa drugs to combat
infections. This created a problem as the burned tissue would
fall away and leave in its place raw areas that were very vulnerable
to infection. Peter tested a variety of antibacterial substances,
finding that some of the sulfa drugs were effective when applied
as a powder to the raw areas. In a tissue culture, one sulfa drug's
crystals actually enhanced the ability of epithelial cells to
spread, using the crystals as a support "pole" for tent-like
coverings. Thus, this drug not only reduced infections but also
accelerated the covering of raw burn areas by new skin growth.
These war wound experiences
also shaped Peter's future research. He became intrigued with
the fact that skin grafts only worked if the grafted skin came
from the same person receiving the graft. Somehow, the body could
recognize alien tissue and would not accept it. How? He took on
this problem as his "duty and pleasure" to investigate.
As World War II continued in Europe, he applied for and received
a grant to study the issue in a surgical unit where there were
plenty of patients with skin wounds needing grafts.
One of his first clues
was the observation that a second graft of "foreign"
skin did not last as long as the first one. This suggested that
the body had some kind of memory of the first graft experience.
He and his colleague, Tom Gibson, published a paper on the data
and concluded that the body has a mechanism that resists alien
tissue, much like the mechanism by which the body resists other
foreign invaders, such as bacteria, viruses, and parasites. The
mechanism allows the body to adapt to or reject foreign intrusion.
Moreover, the resistance system can retain a residual memory and
respond even more vigorously at the second time of exposure.
Peter then embarked on
a large program involving animal testing of skin-graft rejection.
He cut and stained tissue samples taken from the grafts and observed
cellular changes occurring at various stages of graft rejection.
Because the war was in full sway, Peter had little help. He was
responsible for all of the animal feeding, surgeries, nursing
care, and laboratory work. He felt guilty if he did less, though
he took some comfort from the fact that he was helping to develop
treatments for war injuries. He was also proud to be teaching
medical students who would become the doctors saving lives during
the war. He acquired the habit of working long days and bringing
home a briefcase of documents to read before the next morning.
most important work was to demonstrate that the rejection of donor
grafts was due to an immunological reaction and that tolerance
could be built up by injections into embryos. Thus was born the
idea of acquired immunological tolerance, an idea that is still
spawning new research to this day, because how this tolerance
develops is still not fully understood. The body's capacity for
reacting to foreign proteins can be reduced by repeated exposure
to the protein, preferably in small, graded amounts. Applications
of Peter Medawar's research include the common practice of treating
allergies with allergy shots and of reducing rejection of tissue
transplants. Although most of his work was immediately accepted
and appreciated by his peers, Peter is often quoted for the famous
human mind treats a new idea the way the body treats a strange
protein -- it rejects it.
For his important discoveries,
Peter was awarded the Nobel Prize in 1960. It was his research
on tissue transplantation which eventually helped make organ transplants
His book, "Advice
to a Young Scientist," has been widely read and is still
Peter. 1990. The Threat and the Glory. Reflections on Science
and Scientists. Harper Collins. New York, N.Y.
Medawar, Peter. 1986. Memoir of a Thinking Radish. Oxford University
Press, Oxford, England.
Medawar, Peter. 1973. Advice To A Young Scientist. Harper and
Row, New York.
- In Memoriam Testimonial
Why It Matters |
How We Find Out |
What We Know |
Common Hazards |
Self-Study Game |
Teachers Pages |
Peer Curriculum |
Organ Systems Home Page |
Copyright © 2001-2003
Web Site Privacy Statement