High-level secretion of tumor necrosis factor-alpha contributes to hematopoietic failure in hairy cell leukemia [see comments]

Abstract Hairy cell leukemia (HCL) is frequently associated with severe pancytopenia. The authors detected high levels of tumor necrosis factor (TNF)-alpha in the bone marrow serum of patients with HCL and found anti-TNF-alpha neutralizing monoclonal antibodies (MoAbs) to be able to enhance hematopoiesis of HCL patients in in vitro colony assays. As potent producers of TNF-alpha, hairy cells could be identified, thus implicating the malignant population in the pathogenesis of hematopoietic failure due to inappropriate secretion of this cytokine.

Human interleukin 2: molecular biology, physiology and clinical possibilities.

Leukemic Colony-Forming Cells in Acute Myeloblastic Leukemia: Maturation Hierarchy and Growth Conditions

Despite their primitive morphological appearance, the majority of leukemic blasts in acute myeloblastic leukemia (AML) are end-stage, nonproliferating cells. Only a small subset of AML blasts are capable of a sufficient number of divisions to form colonies in semisolid medium [1, 2]. It has been suggested that these leukemic colony-forming cells (L-CFC) may act in vivo as progenitor cells to maintain the rest of the leukemic cell population [3, 4]. L-CFC share several properties with normal myeloid progenitor cells, including self-renewal potential and high thymidine suicide index [2, 3]. As in the case of normal myeloid progenitor cells (NMPC), colony growth of L-CFC from most patients req…

Hematopoietins: New Tools in the Treatment of Hematopoietic Insufficiency

The number of circulating blood cells and their function are regulated by a variety of peptide hormones, the so-called hematopoietic growth factors (HGFs) or hematopoietins. In a complex regulatory network of stimulating and inhibiting peptide hormones [1], the number of circulating blood cells is kept at a physiological level. Because many of these blood cells have a relatively short half-life, the bone marrow is in a state of constant active proliferation in order to produce the necessary blood cells. For instance, granulocytes are made at a rate of 5 × 107–10 × 107 cells/s. It is unclear whether additional, hematopoietin-independent regulatory mechanisms exist, which might be responsible…

Scientific Proceedings Second International Symposium on Cytostatic Drug Resistance