Landsteiner, Karl WORLD OF MICROBIOLOGY AND IMMUNOLOGY338•
her career, she identified over fifty types, and since her death in
1981, bacteriologists have identified thirty more.
Lancefield’s classification converged with another typ-
ing system devised by Frederick Griffith in England. His typ-
ing was based on a slide agglutination method, in which the
bacteria in the serum collect into clumps when an antibodyis
introduced. For five years the two scientists exchanged sam-
ples and information across the Atlantic Ocean, verifying each
other’s types, until Griffith’s tragic death during the bombing
of London in 1940. Ultimately, Lancefield’s system, based on
the M types, was chosen as the standard for classifying group
A streptococci.
In further studies on the M protein, Lancefield revealed
this antigen is responsible for the bacteria’s virulence because
it inhibits phagocytosis, thus keeping the white blood cells
from engulfing the streptococci. This finding came as a sur-
prise, because Avery had discovered that virulence in the
Pneumococcuswas due to a polysaccharide, not a protein.
Lancefield went on to show the M antigen is also the one that
elicits protective immune reactions.
Lancefield continued to group and type strep organisms
sent from laboratories around the world. Until the end of her
life her painstaking investigations helped unravel the com-
plexity and diversity of these bacteria. Her thoroughness was
a significant factor in her small but substantial bibliography of
nearly sixty papers.
Once her system of classification was in place, how-
ever, Lancefield returned to her original quest to elucidate
connections between the bacteria’s constituents and the baf-
fling nature of streptococcal diseases. She found that a single
serotype of group A can cause a variety of streptococcal dis-
eases. This evidence reversed a long-standing assumption that
every disease must be caused by a specific microbe. Also,
because the M protein is type-specific, she found that acquired
immunity to one group A serotype could not protect against
infections caused by others in group A.
From her laboratory at Rockefeller Hospital, Lancefield
could follow patient records for very long periods. She con-
ducted a study that determined that once immunity is acquired
to a serotype, it can last up to thirty years. This particular study
revealed the unusual finding that high titers, or concentrations,
of antibody persist in the absence of antigen. In the case of
rheumatic fever, Lancefield illustrated how someone can suf-
fer recurrent attacks, because each one is caused by a different
serotype.
In other studies, Lancefield focused on antigens. She and
Gertrude Perlmann purified the M protein in the 1950s. Twenty
years later she developed a more conservative test for typing it
and continued characterizing other group A protein antigens
designated T and R. Ten years after her official retirement, she
made a vital contribution on the group B streptococci. She clar-
ified the role of their polysaccharides in virulence and showed
how protein antigens on their surface also played a protective
role. During the 1970s, an increasingly high-rate of infants
were born with group B meningitis, and her work laid the basis
for the medical response to this problem.
During World War II, Lancefield had performed special
duties on the Streptococcal Diseases Commission of theArmed Forces Epidemiological Board. Her task involved
identifying strains and providing antisera for epidemicsof
scarlet and rheumatic fever among soldiers in military camps.
After the commission dissolved, her colleagues in the “Strep
Club” created the Lancefield Society in 1977, which continues
to hold regular international meetings on advances in strepto-
coccal research.
An associate member at Rockefeller when Maclyn
McCarty took over Swift’s laboratory in 1946, Lancefield
became a full member and professor in 1958, and emeritus pro-
fessor in 1965. While her career and achievements took place
in a field dominated by men, Lewis Wannamaker in American
Society for Microbiology News quotes Lancefield as being
“annoyed by any special feeling about women in science.”
Nevertheless, most recognition for Lancefield came near her
retirement. In 1961, she was the first woman elected president
of the American Association of Immunologists, and in 1970,
she was one of few women elected to the National Academy of
Sciences. Other honors included the T. Duckett Jones
Memorial Award in 1960, the American Heart Association
Achievement Award in 1964, the New York Academy of
Medicine Medal in 1973, and honorary degrees from
Rockefeller University in 1973 and Wellesley College in 1976.
In addition to her career as a scientist, Lancefield had
one daughter. Lancefield was devoted to research and pre-
ferred not to go on lecture tours or attend scientific meetings.
Rockefeller’s laboratories were not air-conditioned and her
main diversion was leaving them during the summer and
spending the entire season in Woods Hole, Massachusetts.
There she enjoyed tennis and swimming with her family,
which eventually included two grandsons. Official retirement
did not change her lifestyle. She drove to her Rockefeller lab-
oratory from her home in Douglaston, Long Island, every
working day until she broke her hip in November 1980. She
died of complications from this injury on March 3, 1981, at the
age of eighty-six.
The pathogenesis of rheumatic fever still eludes scien-
tists, and antibioticshave not eliminated streptococcal dis-
eases. Yet the legacy of Lancefield’s system and its
fundamental links to disease remain and a vaccineagainst
several group A streptococci is being developed in her former
laboratory at Rockefeller University by Vincent A. Fischetti.See alsoBacteria and bacterial infection; Streptococci and
streptococcal infectionsLLandsteiner, Karl ANDSTEINER, KARL(1868-1943)
American immunologistKarl Landsteiner was one of the first scientists to study the
physical processes of immunity. He is best known for his iden-
tification and characterization of the human blood groups, A,
B, and O, but his contributions spanned many areas of
immunology, bacteriology, and pathology over a prolific forty-
year career. Landsteiner identified the agents responsible for
immune reactions, examined the interaction of antigens and
antibodies, and studied allergic reactions in experimental ani-womi_L 5/6/03 3:31 PM Page 338