Blood, 1961, Vol. 18, No. 2, pp. 133-148.
© 1961 American Society of Hematology, Inc.
Red Cell Filtration and the Pathogenesis
of Certain Hemolytic Anemias
JAMES H. JANDL 1,
RICHARD L. SIMMONS 1, and
WILLIAM B. CASTLE 1
1 Thorndike Memorial Laboratory and Second and Fourth (Harvard) Medical
Services, Boston City Hospital, and the Department of Medicine, Harvard Medical School,
Boston, Mass.
Studies were made of the filterability of normal and abnormal red cells
through an inert membrane-type (Millipore) filter having uniform non-branching capillary pores 5 µ in diameter. With this filter it was possible to
remove selectively certain kinds of abnormal red cells from mixed suspensions
of normal and abnormal red cells.
The red cells of patients with sickle cell anemia were selectively trapped
by the filter under low oxygen tensions. Such sickled red cells were unable
to pass through the filter even under a pressure differential across the filter
(perfusion pressure) of over 120 mm. Hg.
Red cells agglutinated by anti-A were completely retained by the filter at
perfusing pressures of 4 mm. Hg., but were partially disagglutinated and
forced through the filter when the pressure was increased. Red cells coated
with an incomplete (Rh) agglutinin and red cells from a patient with acquired hemolytic anemia were retained by the filter only in the presence
of rouleaux-producing agents such as P.V.P. or fibrinogen and only at low
perfusion pressures.
A small fraction of the red cells of patients with hereditary spherocytosis
were trapped by a single passage through the filter; the trapped cells were
largely derived from the minor population of hyperspheroidal cells.
The relevance of these findings to the mechanisms of red cell sequestration
in vivo is discussed.
Submitted on February 17, 1961
Accepted on May 12, 1961
