Blood and Bone Marrow

  • Herbert Begemann
  • Johann Rastetter


Proerythroblasts, also called pronormoblasts or rubriblasts, are the earliest precursors of erythropoiesis. They do not yet contain any hemoglobin. Their size ranges from 15 to 22 µm. The dark basophil, frequently lightly shaded cytoplasm is characteristic. The nucleus reveals a dense, fine honeycombed chromatin structure. As a rule, several, up to 5, pale blue nucleoli are present, which are difficult to define, however, and disappear on further maturation of the cell. In conjunction with all erythropoietic cells, proerythroblasts tend to produce multinucleated forms, but less so than plasma cells. A light area in the cytoplasm near the nucleus is typical which appears as finely granular by phase contrast microscopy. Hemoglobinization also commences at the nucleus: at first there is a lighter perinuclear zone (cells 1, 3, 8, 9), that eventually occupies the whole cell and directly passes to the polychromatic forms (cells 7–10). Simultaneously, the nucleus undergoes a characteristic change in structure: the nucleoli disappear. The chromatin stroma becomes coarser and transforms to the typical erythroblast nucleus.


Bone Marrow Plasma Cell Chronic Myeloid Leukemia Hemolytic Anemia Acute Leukemia 
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  1. Bessis, M.: Living blood cells and their ultrastructure. Berlin-Heidelberg-New York: Springer-Verlag 1973Google Scholar
  2. Huhn, D., Stich, W.: Fine structure of blood and bone marrow. Munich: J.F. Lehmann 1969Google Scholar
  3. Ruzicka, F.: Elektronenmikroskopische Hämatologie. Vienna-New York: Springer-Verlag 1976CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin-Heidelberg 1979

Authors and Affiliations

  • Herbert Begemann
    • 1
  • Johann Rastetter
    • 2
  1. 1.I. Medizinischen AbteilungStädtischen Krankenhauses München-SchwabingMünchenGermany
  2. 2.Abteilung für Hämatologie und Onkologie, I. Medizinische Klinik rechts der IsarTechnischen Universität MünchenGermany

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