4-acetamido-4--isothiocyanatostilbene-2-2--disulfonic-acid and Leukemia

The Cl- transport characteristics of the human leukemic cell lines K562 and HL60, with erythroid and granulocytic phenotypic features, respectively, were investigated. Cl- effluxes were measured with 36Cl- under equilibrium conditions in both cell lines and were found to be three orders of magnitude slower than the unidirectional efflux of Cl- in normal erythrocytes. Induction of differentiation of the K562 cell line with hemin does not affect the rate of Cl- transport, while induction of the HL60 cell line with dimethyl sulfoxide results in a small decrease in the rate of Cl- transport. Cl- transport in both cell lines could be divided into two components. One component is inhibited by treatment with 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), displays counter-transport characteristics, and has a high energy of activation--all properties characteristic of the human erythrocyte-facilitated anion exchange system. The second component is insensitive to DIDS, is partially inhibited by furosemide, and has a low energy of activation.

Topics: 4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; Affinity Labels; Biological Transport, Active; Cell Differentiation; Cell Line; Chlorides; Chlorine; Dimethyl Sulfoxide; Furosemide; Hemin; Humans; In Vitro Techniques; Ion Channels; Leukemia; Potassium Radioisotopes; Radioisotopes; Sodium Radioisotopes