The in Vitro Activity of Two Urinary Polypeptides Respect to G- and GM-CSF and IL3 on the Peripheral CFU of Normal and Leukemic Subjects

Abstract

We isolated two polypeptides on HPLC from the acetonic precipitate of the urine of normal subjects and of patients with untreated AML, APL and AMML. Before separation the quantity of the total urinary factor from leukemic patients was 50±10 mg/24h and from normal subjects was 10±5 mg. We tested the total polypeptidic extract and the two main fractions obtained on liquid cultures of the peripheral CFU of normal and leukemic subjects (AML, APL, CML and CMmL). Colony growth, cell morphology changes and the main cellular markers were examined at the beginning and at the 5th and 10th days of incubation in RPMI 1640 medium. Testing conditions were basal and as determined by the addition of the polypeptidic fractions, both alone and in association with trans-retinoic acid (t-RA) or thioproline (T). Simultaneously and under the same experimental conditions, we tested the activity of G- and GM-CSF and IL3. The results obtained prove the colony stimulating activity of the two fractions and of crude extract; they also prove the ability of such agents to modify the behavior in vitro of peripheral CFU. The urinary extracts are also able to stimulate a moderate differentiation of the elements and an increase both in fibroblasts and in adhesion molecules. We conclude that the dosage of growth factors in urine may be usefull as important marker in several hemopoietic pathological conditions or as a possible source of growth factors.