Maturation of Megaloblasts in Bone Marrow Cultures

Abstract

Investigating the effect of folic acid upon the maturation of megaloblasts, we used a modified bone-marrow culture method of Osgood. During our experiments we saw megaloblasts ripen not only in media containing folic acid, but also in those which contained only the prescribed Osgood medium (65 per cent Gey solution and 35 per cent serum obtained from placental vein). Supposing that the placental serum might contain certain substances responsible for cell growth, in the next stage of our experiment we used normal adult serum instead of the placental one. To our surprise we found that megaloblasts ripen even in these conditions. (At the beginning, the megaloblast ratio of all nucleated red blood corpuscles was 50 per cent, 48 hours later only 8 per cent.) In the third stage of our experiments we further modified Osgood's method and used sera obtained from patients suffering from pernicious anæmia. We had every reason to suppose that normal serum might contain the anti-anæmic factor, which is absent in pernicious anæmia sera. Hence, we put the bone marrow simultaneously into vessels containing normal, and others containing pernicious anæmia sera, both prepared under the same conditions as above. The surprising result was that megaloblasts ripened in the pernicious anæmia medium too, although to a lesser extent. (Example: decrease of the relative number of the megaloblasts in 48 hours from 50 to 18 per cent.)