BURST-PROMOTING ACTIVITY (BPA) WITHOUT ERYTHROPOIETIN (EP) ACTIVITY IN SERA OF APLASTIC-ANEMIA PATIENTS FRACTIONATED BY CHROMATOFOCUSING COLUMN

  • 1 January 1982
    • journal article
    • research article
    • Vol. 10  (10) , 844-851
Abstract
A chromatofocusing column was used to separate burst-promoting activity (BPA) and erythropoietin (Ep) acivity in sera from patients with aplastic anemia. A fraction containing a considerable level of BPA without Ep activity was found at .apprx. pH 5.0. Another fraction at lower pH contained both activities. This is the 1st report of the existence of a fraction with BPA but without Ep activity in sera from aplasia patients. In trying to measure BPA in sera and urine, a new assay procedure was which involved counting the number of erythroid bursts in normal human marrow cell cultures initiated with test samples to which 1-2 U of standard Ep were added 5-6 days later. Separation of BPA from Ep activity in patients sera was also attempted by Sephadex G-100, but this was unsuccessful due to the presence of inhibitors to burst formation. In urine sepration, BPA and Ep activities were eluted in the same fraction. Sephadex G-100 chromatography indicated separation of BPA from Ep activity, however, this may have been due to the presence of inhibitor(s). The peaks of both activities apparently coincided with a urine preparation containing no inhibitors was tested.