Der vitamin B 12-stoffwechsel bei hämoblastosen : II. Die intravitale bindung (transport) der B 12-vitamine an die serumproteinfraktionen bei hämoblastosen

Abstract

After fractionation of serum proteins by paper electrophoresis the vitamin B 12 bound to the single fractions was estimated microbiologically. In healthy persons about 52% of the bound B 12 is attached to the α 1-globulin, 21% to the α 2-globulin and 16% to the albumin. (α 1-Globulin binds 3 times as much as α 2-globulin and albumin, 10 times as much as β-globulin and 28 times as much as γ-globulin). In cases of chronic myeloid leucaemia the amount of B 12 bound to α 1-globulin, albumin and α 2-globulin increases strongly in relation to the greatly increased vitamin B 12 concentration in the serum. There were no essential quantitative changes in the serum protein fractions in myeloid leucaemia. Compared with the amounts in healthy persons 19 times as much α 1-globulin-bound, 9 times as much α 2-globulinbound, II times as much albumin-bound B 12 has been ascertained. In patients with chronic myeloid leucaemia about 75% of the bound B 12 is attached to α 1-globulin and about 12% each to both α 2-globulin and albumin. During X-ray therapy the B 12 bound to the three fractions decreases in connection with the reduction of B 12 in the serum, without changing the percentage distribution, and then rises again in relapse.