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The discovery of the ruddy globules (red cells) is attributed to Jan Swammerdam (1637-1680) in Amsterdam; but, it was Antonj van Leeuwenhoek (1632-1723) of Delft, who as a result of his ability to grind lenses with greater magnifying power (x 275), made a more detailed description of red cells, delineating their gross structure.
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The biochemistry, physiology, and biophysics of the red cell have been studied intensively over three centuries and, although considered a “simple” structure, since it is anucleate and after one day in the circulation has no cytoplasmic organelles, its mysteries have been slow to be unraveled. The process of enucleation of the erythroblast in the hematopoietic space and the movement of the anucleate cell from the hematopoietic space to the marrow sinus and from there to the systemic circulation, accomplished by a cell without an intrinsic apparatus to support amoeboid motility, and the determinants of its average life span of approximately 120 days are still being elucidated. Its structural and biophysical properties, biochemical pathways, and the relationship among those features have been of continued interest to scientists. Its absence of interfering granules, containing proteolytic enzymes, organelles, and other complexities have allowed the isolation of highly purified red cell membranes and the early exploration of the biochemical and biophysical features of cell membranes, applicable to other cells, including the characteristics of membrane transport of various molecules. The nature of the structure and function of hemoglobin and the exploration of the glycolytic pathway, the hexose monophosphate shunt, and the Luebering-Rapoport pathway were other rewards reaped from the study of red cells.
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Much is known, but as our mentor, friend, and colleague, Ernest Beutler, cautioned Ph.D. graduates at a Scripps Institute doctoral graduation, one should not assume that our understanding of the biomedical sciences is so profound that what is left for us is to fill in some gaps. He argued that much fundamental biomedical knowledge was still undiscovered and waiting to be illuminated. Among his many contributions to the pathogenesis of disease and application of therapy, his contributions to understanding the red cell and anemia were notable. These observations included a classic series of papers describing the effects of oxidant stress on individuals with red cell glucose-6-phosphate dehydrogenase deficiency and a life-long interest in the enzyme’s variants and epidemiology. His monograph on methods for measuring red cell enzymes was an early contribution to enhancing the specificity of the diagnosis of hemolytic anemia. Published over five decades ago, it remains an unsurpassed source of methods for the assay of red cell enzymes. Beutler, also, used red cell enzyme measurement as a surrogate for diagnosis of systemic, until then difficult to diagnose diseases, such as galactosemia, glycogen storage disorders, and others. He found that red cell glucose-6-phosphate dehydrogenase deficiency was inherited as an X chromosome-linked disorder and described the mosaicism of normal and deficient red cells in heterozygous females. This finding of mosaicism provided the basis for an intellectual jump to the hypothesis of X chromosome inactivation in humans, coincident with Mary Lyon’s description of the phenomenon in mice. He, also, made seminal contributions to understanding the effects of iron deficiency in non-anemic women and the expression of iron overload in those homozygous for the HFE mutation and the value of additives for prolonged storage of red cells, still in current use.
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With no DNA or RNA synthesis, no mitochondria and their related enzymatic biochemical energy generating pathways, and with a relatively short life span, this amitotic cell is sustained at a normal concentration in the blood by a robust daily production of new cells in the marrow, the process of erythropoiesis. This process delivers two to three million new red cells to the blood per second. Although remarkable, it is also a vulnerability should red cell production be dampened by disease or substrate insufficiency: the latter, a principal cause of anemia.
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In 1929, 3 years after obtaining his M.D. degree at the University of Manitoba, his family having immigrated to Canada from Austria, Maxwell Myer Wintrobe, obtained his Ph.D. at Tulane University, his doctoral thesis entitled “The Erythrocyte in Man.” Wintrobe is considered the father of clinical hematology having published the first comprehensive text in the English language, Clinical Hematology, in 1942. He introduced the technique of the hematocrit device to measure the packed red cell volume at a time when hemoglobin and red cell count measurements were neither accurate nor reproducible. The word “hematocrit” was so appealing that it became a synonym for the packed red cell volume rather than the instrument of measurement as intended by Wintrobe. Initially, the “Wintrobe” tube, as it became known, was filled by pipette with blood to the 1 mL mark etched on the tube and the gradations on the tube allowed one to read the fraction of blood that was composed of red cells after centrifugation. Later, the microhematocrit centrifuge, which reached G-forces that removed plasma trapping as a significant consideration in the measurement in capillary tubes filled with blood, could be found on every ward and clinical laboratory as the principal means to measure the packed red cell volume and, thereby, identify anemia or erythrocytosis. A chart allowed the determination of the packed cell volume when the capillary tube, regardless of the volume of blood it contained, was placed against its scales. Wintrobe institutionalized the red cell indices, mean cell volume (MCV), mean cell hemoglobin (MCH), and mean cell hemoglobin concentration (MCHC) and showed in two classic paper in 1930 and 1934 that one could classify the anemias for diagnostic purposes by distinguishing among macrocytic, normocytic, simple microcytic, and hypochromic microcytic anemias, a method of differential diagnosis still used today. After moving to the University of Utah from Johns Hopkins University, Wintrobe established one of the most esteemed hematology clinical and research training programs in the world. He also described along with his colleague George Cartwright that the average hematocrit and hemoglobin concentration was higher in residents of Salt Lake City (elevation 4300 feet) than the value observed at Johns Hopkins in Baltimore (elevation 480 feet). He deduced from that prescient observation that hypoxia, in that instance from higher altitude, is a principal regulator of normal erythropoiesis.
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In 1953, F. William Sunderman and colleagues enhanced the accuracy of blood hemoglobin measurement by introducing the cyanmethemoglobin method. In 1956, Wallace Coulter introduced his high-speed, automatic blood cell counter making blood cell counting accurate, reproducible, and capable of meeting the demands of a busy clinic and hospital environment. The “Coulter Principle” held that cells are poor conductors of electricity in a salt solution. Thus, when cells are diluted in saline and are drawn through a tiny aperture carrying a current, each cell produces a slight impedance to current flow as it passes through the narrow aperture. The pulse created by this impedance can be amplified and counted. Moreover, the size of the pulse is proportional to cell volume. Thus, the number and volume distribution of red cells in a measured volume of solution can be converted to red cell count and volume electronically. Their product, red cell count and red cell volume, provided the hematocrit, now a derived value. Thousands of cells can be counted per second. Since the red cells, leukocytes, and platelets are sufficiently different in size, they can be discriminated. The electronic particle counter’s derivative technology of cell flow analysis, dependent on laser light, provided one of the most powerful diagnostic technologies in medicine, capable of measuring cell DNA content or the surface antigen array of a specific cell type. One could use the device to isolate purified, specific cell populations for analysis. The Coulter Principle and its derivative technologies revolutionized diagnostic medicine, biomedical, and industrial research and, more specifically, the diagnosis and management of red cell diseases.
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A giant of studies of the red cell, perhaps little known to younger scientists, was Eric Ponder (d. 1970), an original member of the Red Cell Club (see further), whose treatise Hemolysis and Related Phenomena in 1948, reissued in 1971 by Grune and Stratton with a forward by Robert I. Weed, is an extraordinary compilation of his research on this cell. Many of his studies are still relevant. All scientist interested in the red cell should be familiar with this work. Weed, another gifted contributor to our understanding of the red cell, died prematurely in 1976, at the age of 48 years, of a glioblastoma. He was largely responsible for convincing the National Institutes of Health to expand the designation of the Heart and Lung Institute to the Heart, Lung and Blood Institute in 1976, facilitating research support for blood cells, especially red cell research. In 1976, in recognition of his leadership in that initiative and his contributions to research on the red cell, he was named the third recipient of the William Dameshek Award of the American Society of Hematology. At the time, the Society had two prizes, The Henry Stratton Lecture and The William Dameshek Prize. Stratton and Dameshek were very close friends. Dameshek was among the very top academic clinical hematologists in the United States and Stratton was the co-owner of Grune and Stratton Publishers. They were the prime movers of the establishment of the American Society of Hematology and started Blood in 1946. Dameshek was the founding editor and Grune and Stratton the publisher. Under Dameshek’s editorship Blood became the most prestigious journal of clinical and research hematology in the world. In 1976, the journal became the official publication of the American Society of Hematology; however, the publisher still owned the title and, technically, editorial control, but some of it was ceded to the Society. In 1989, the American Society of Hematology bought the title to Blood from its then publisher Saunders, Inc. and it became Blood, The Journal of the American Society of Hematology. The purchase of title was an initiative led by H. Franklin Bunn, a distinguished hematologist at Harvard University and a world’s authority on the structure and function of hemoglobin. The purchase of the Journal has provided the Society with an enormously successful economic engine to support its educational and research programs, full control of its editorial policies, and an outlet for the most impactful research in the field, including that of the red cell and its diseases.
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Bob Weed’s close colleagues at the University of Rochester, Claude Reed and Scott Swisher, were pioneers in forecasting the key role of a membrane protein abnormality as the primary lesion in hereditary spherocytosis, whereas others were distracted by epiphenomena, such as substrate transport. They showed that the membrane lipid composition of red cells in hereditary spherocytosis was normal but after 24 hours of incubation, lipids (cholesterol and phospholipids) were lost to the medium in their exact molar proportion as in the red cell membrane and this phenomenon could be decreased by adding glucose to the medium. This finding strongly suggested that the loss of surface area of the red cells and the disc to sphere transformation decreasing their surface area to volume ratio and moving toward their critical hemolytic volume was related to loss of pieces of membrane. This work published in 1966 was well before methods for membrane protein analysis were available. Later, the ability to characterize the protein composition of “pure” red cell membranes (ghosts) in cases of specific disorders of the red cell (eg, hereditary spherocytosis versus hereditary elliptocytosis) allowed the assignment of functional characteristics to the missing or mutant proteins. Red cell ghosts are a preparation of red cell membranes freed of their internal contents, notable hemoglobin and enzymes and substrates and colorless (ghostly pale) rather than red and are basically pure red cell membranes, a key specimen for study.
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A longstanding focus on the red cell by basic and clinical investigators has been highlighted by the interactions of a group of scientists, referred to as “The Red Cell Club,” which started in 1958 through the initiative of Joseph Hoffman and Daniel Tosteson, then young scientists at the National Institutes of Health. The spent their careers at Yale and Harvard, respectively. The meetings are small, informal, and an ideal milieu to focus on new science and the exchange of ideas. The Club, in its 63rd year in 2021, meets now once a year on the campus of a member to discuss new insights into the red cell and to share their current research. It is a collegial group with new “blood” being cycled in from laboratories throughout the United States and Canada as mentors introduce their acolytes to the red cell’s charms. Usually, a preceding round of golf is held for those devotees of the game, weather permitting. Members, who for reasons of age or a change of interests leave the fold, are never dropped from the invitation list. Nonparticipants are tenderly referred to as “red cell ghosts.” In the last several years, scientists from Europe and, occasionally Japan, have participated in these meetings. A European Red Cell Club has been established highlighting that the mysteries of the cell have not all been uncovered, confirming Beutler’s admonition.
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In this volume, we bring to the reader the most up-to-date consideration of the structure and function of the red cell. After two introductory chapters on the structure and biology of the red cell and erythropoiesis, the focus turns to the comprehensive set of diseases, either acquired or inherited, in which a quantitative (deficiency or excess) or qualitative (membrane, enzyme, hemoglobin) abnormality of the red cell results in disease. These chapters, also, may include important, relevant basic scientific aspects of the clinical problem under discussion. The role of certain plasma constituents, iron, folic acid, and cobalamin, critical to normal red cell production and hemoglobin synthesis, is described as well.
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We believe the authors have brought to our reader an insightful exposition of the red cell and its disorders to enlighten the clinicians faced with their challenges and to the benefit of the care of their patients. In addition, we hope this text provides scientists a clear delineation of the remaining mysteries of the cell and provides them with new foundations for development of therapy of red cell diseases. We hope that this text will fill the vacuum that has existed since the monograph published in 1970 devoted to the red cell by John W. Harris, and Robert W. Kellermeyer: The Red Cell: Production, Metabolism, Destruction: Normal and Abnormal.
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The authors acknowledge and thank Karen Edmonson, Senior Editor, formerly at McGraw-Hill, Education, for supporting the production of this text and convincing management of its merits, Susan Daley at the University of Rochester Medical Center for her administrative assistance, Harriet Lebowitz, Senior Project Development Editor at McGraw-Hill Education for stewarding the final preparation of the manuscript and Jason Malley, editor and Richard Ruzycka, production supervisor, each at McGraw-Hill Education, and Warishree Pant, the Project Manager at Knowledge Works Global, Ltd.
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Marshall A. Lichtman, Rochester, NY
Josef T. Prchal, Salt Lake City, UT