chondroitin-sulfates and Leukemia--Myeloid--Acute

Four patients with acute promyelocytic leukemia (APL) and clinical and laboratory manifestations of disseminated intravascular coagulation (DIC) were treated during induction chemotherapy with Org 10172 (Organon International), a low molecular weight heparinoid preparation. Plasma anti-Xa levels were maintained between 0.60 and 0.80 U/ml and anticoagulant activities, determined with a diluted activated partial thromboplastin time assay, ranged from 0.00 to 0.20 U/ml. Bleeding symptoms ceased and fibrinogen levels improved in the first week in all patients. In the second week, two patients developed bleeding as a result of primary fibrinolysis. It is concluded that Org 10172 may be useful in the treatment of patients with DIC. In patients with APL, inhibition of DIC will be insufficient to control all bleeding, since primary fibrinolysis may also occur.

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Chondroitin Sulfates; Cytarabine; Daunorubicin; Dermatan Sulfate; Disseminated Intravascular Coagulation; Drug Evaluation; Glycosaminoglycans; Heparinoids; Heparitin Sulfate; Humans; Leukemia, Myeloid, Acute; Middle Aged; Thioguanine; Time Factors

Reductions in glycosaminoglycan(s) (GAGs) have been reported during the process of leukemia cell differentiation. It has been suggested that GAG depletion may facilitate critical membrane interactions, perhaps by exposing membrane receptors to differentiation inducers. We have investigated the effects of enzymatic removal of HL-60 cell surface GAG on maturation events. Cells treated with chondroitin ABC lyase to remove surface chondroitin sulfate, which is the major GAG constituent, did not demonstrate altered binding affinity for the differentiation inducer, 12-O-tetradecanoylphorbol-13-acetate (TPA). Similarly, a complex membrane antigen associated with maturation, the chemotactic peptide receptor, was not perturbed. These GAG-depleted cells did not spontaneously mature or have altered sensitivity to a variety of inducers. Therefore, these results suggest that surface GAG depletion does not alter the availability of surface receptors associated with the induction process.

Topics: Cell Differentiation; Cell Membrane; Chondroitin Lyases; Chondroitin Sulfates; Glycosaminoglycans; Humans; Leukemia, Myeloid, Acute; N-Formylmethionine Leucyl-Phenylalanine; Phorbol 12,13-Dibutyrate; Phorbol Esters; Trypsin

A clone of natural killer (NK) cells (JTB18) was found to be ultrastructurally similar to peripheral blood large granular lymphocytes (LGL). These cells incorporated [35S]sulfate into cell-associated proteoglycan molecules, which were then isolated by CsCl density gradient centrifugation. As assessed by gel filtration chromatography, the native 35S-labeled proteoglycan and its beta-eliminated 35S-labeled glycosaminoglycans were of Mr approximately 200,000 and 50,000, respectively. The 35S-labeled proteoglycans were resistant to proteolysis, since their Mr were apparently not altered by incubation with either pronase or S. aureus V8 protease. The purified NK cell 35S-labeled proteoglycans were degraded by approximately 90% to 35S-labeled disaccharides with either chondroitinase ABC or AC. High performance liquid chromatographic analysis of the digests revealed these disaccharides to be composed entirely of chondroitin sulfate A (glucuronic acid----N-acetylgalactosamine-4SO4). Whole 35S-labeled cells incubated with chondroitinase ABC failed to release 35S-labeled disaccharides into the supernatant, and x-ray energy-dispersive analysis revealed that sulfur-containing molecules were present in the intracellular granules, thereby localizing the NK cell-associated proteoglycan primarily in the granules of the cell, rather than on the plasma membrane. The 35S-labeled cloned NK cells incubated for 30 min to 4 h with K562 tumor cell targets at a 0.5:1 ratio exocytosed a mean of 49% of the granular 35S-labeled proteoglycans during the first 60 min of the culture. Proteoglycan release was maximal with an effector/target cell ratio of 0.5:1 for JTB18:K562. Significant proteoglycan release from JTB18 NK cells was also obtained with other sensitive target cells such as REX, Molt4, and CEM, but not with cells such as KG1 and Laz156, which have been shown previously to be resistant to killing by this NK cell. Thus, protease-resistant intracellular proteoglycans with chondroitin sulfate A side chains are specifically exocytosed from the granules of human NK effector cells upon contact with sensitive targets, suggesting that these proteoglycans may be involved in the mechanism of cytotoxicity.

Topics: Cell Line; Chondroitin; Chondroitin Sulfates; Clone Cells; Cytoplasmic Granules; Cytotoxicity, Immunologic; Exocytosis; Humans; Killer Cells, Natural; Leukemia, Myeloid; Leukemia, Myeloid, Acute; Macromolecular Substances; Microscopy, Electron