title: Hematopoietic growth factors in human serum. erythroid burst-promoting activity in normal subjects and in patients with severe aplastic anemia.
abstract: The activity capable of promoting the growth of human erythroid burst-forming cells (BFU-E) in culture was measured in the sera from 39 patients with aplastic anemia (AA) and compared with similar activity in patients with various other hematologic disorders and 31 normal subjects. Burst-promoting activity (BPA) was determined by its ability to support erythroid burst growth from adherent cell-depleted normal human marrow cells. The results were expressed as the percentage of burst growth supported by test serum compared with cultures established in the presence of 20% test serum and 2.5% phytohemagglutinin-stimulated lymphocyte conditioned medium. The mean BPA level in normal serum was 18.5% (1.5 +/- SEM) and was not significantly different from BPA levels in patients with various forms of nonhypoplastic anemia or polycythemia (10.2% +/- 1.2%). In contrast, 15 of the 39 patients with AA had elevated BPA levels, ranging from 40.0% to 106.0%. These elevated levels did not correlate with serum erythropoietin or hematocrit values, white blood cell count, platelet count, time from diagnosis, or the presence or numbers of BFU-E in circulation. The BPA was shown not to be T cell growth factor (interleukin-2), and the effect was not blocked by the addition of cyclosporine to culture, consistent with a direct effect of this activity on BFU-E. When the 39 patients with AA were treated with antithymocyte globulin, 20 obtained a complete or partial remission. BPA levels determined from sera obtained before treatment did not correlate with response or duration of survival but did correlate with granulocyte-macrophage colony-stimulating activity (GM-CSA).(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000293:Adolescent; D000328:Adult; D000741:Anemia, Aplastic / Q000097:blood*; D001854:Bone Marrow Cells; D002648:Child; D002675:Child, Preschool; D003524:Cyclosporins / Q000494:pharmacology; D004921:Erythropoietin / Q000302:isolation & purification* / Q000502:physiology / Q000652:urine; D005260:Female; D006400:Hematocrit; D006412:Hematopoietic Stem Cells / Q000166:cytology; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000166:cytology / Q000187:drug effects; D010976:Platelet Count; D012016:Reference Values
chemical_list: D003524:Cyclosporins; D004921:Erythropoietin