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Transformation of Megaloblasts to Normoblasts by cultivating Human Bone Marrow in Presence of Vitamin B12 and Vitamin B12-binding Protein


Callender and Lajtha1 observed that little or no conversion of megaloblasts to normoblasts occurred when pernicious anæmia marrow was cultivated in pernicious anæmia serum by itself or together with vitamin B12. However, if bone marrow is cultivated in pernicious anæmia serum containing vitamin B12 and normal gastric juice or in normal serum with vitamin B12 megaloblasts are partly converted into normoblasts within twenty-four hours. Swan et al. 2 did not find this influence of vitamin B12 and gastric juice, but Astaldi and Cardinali3 have recently confirmed the findings of Callender and Lajtha1.

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  1. 1

    Callender, S. T., and Lajtha, L. G., Blood, 6, 1234 (1951).

  2. 2

    Swan, H. T., Reisner, E. H., and Silverman, M., Blood, 10, 735 (1955).

  3. 3

    Astaldi, G., and Cardinali, G., “1 Europaisches Symposion Vitamin B12 und Intrinsic Factor”, pp. 341–360, Hamburg, 1956, (Ferdinand Enke Verlag, Stuttgart, 1956).

  4. 4

    Osgood, E. E., and Brawnlee, I. E., J. Amer. Med. Assoc., 108, 1793 (1937).

  5. 5

    Lajtha, L. G., J. Clin. Path., 5, 67 (1952).

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