Biopterin level in peripheral blood cells as a marker for hemopoietic cell proliferation during leukemia and polycythemia vera.

Using the Crithidia assay 3.0 ng biopterin/ml blood was found, of which one third was present in the plasma. The erythrocyte fraction comprised 1.7 ng and the buffy coat 0.33 ng. After Ficoll separation 0.050 ng were found in the lymphocyte layer of 1 ml blood. During blast crisis of chronic myelocytic leukemias increased amounts of biopterin were found in the erythrocyte fraction and in the buffy coat. The high biopterin concentration per unit of protein in the white cell fraction indicated the presence of blasts. In Polycythemia vera increased amounts of biopterin in both the red cell fraction and in the buffy coat were also found but the percentage distribution within total cellular biopterin was markedly shifted toward the erythrocyte fraction. In cases of chronic and acute lymphocytic leukemias the low amounts of biopterin in the red cell fraction agreed with the current view of partial extinction of the erythropoietic line. The isolated lymphoblasts were characterized by high biopterin concentrations per unit of protein. During remission the biopterin patterns approached normal levels.