Molecular mechanisms of sulfasalazine-induced T-cell apoptosis - PubMed (original) (raw)

Sulfasalazine induces apoptosis in Jurkat T-lymphocytes. (A) Jurkat cells were incubated for 24 h with increasing concentrations of sulfasalazine, (B) or with 2.0 m

M

sulfasalazine for the indicated time periods. The percentage of apoptotic cells was determined by FACS analysis on the basis of their characteristic forward/sideward light scatter changes. Data are obtained from three independent experiments done in duplicate and are presented as mean and standard error of the mean (s.e.mean). (C) Sulfasalazine induces chromatin condensation. Jurkat cells were treated for 24 h with medium (control) or 2.0 m

M

sulfasalazine (SS), and examined under a fluorescence microscope after DAPI staining. Representative fields of one out of three independent experiments are shown. (D) Sulfasalazine induces DNA loss. Jurkat cells were treated for 24 h with (SS) or without (control) 2.0 m

M

sulfasalazine, stained with propidium iodide (PI), and analysed by flow cytometry. Numbers above the histogram markers indicate the percentage of apoptotic nuclei (broad hypodiploid peak) in a representative experiment out of four. (E) Sulfasalazine induces oligonucleosomal DNA fragmentation. Jurkat cells were treated for 24 h with medium (lane 2), 150 U ml−1 TNFα (lane 3), 1 m

M

(lane 4) or 2 m

M

sulfasalazine (lane 5). Genomic DNA was extracted and analysed on an ethidium bromide stained agarose gel. As molecular-weight marker a 100 bp DNA marker was used (lane 1). (F) Sulfasalazine induces phosphatidylserine exposure. Jurkat cells were treated with medium (control), or 2.0 m

M

sulfasalazine for 6 or 24 h as indicated. Cells were stained with FITC-conjugated annexin V and analysed by FACS. Numbers above the histogram markers indicate the percentage of apoptotic cells in a representative experiment out of four. Viability of (G) SW620 cells, a human colon carcinoma cell line, and (H) human primary synoviozytes is not affected by sulfasalazine. Cells were incubated with 2 m

M

sulfasalazine for the indicated time periods. Cell death was determined by trypan blue exclusion.