Dimethyl sulfoxide induces programmed cell death and reversible G1 arrest in the cell cycle of human lymphoid pre-T cell line.

In human B- and T-differentiated lymphoid cell lines DMSO was found to arrest the proliferation at the G1 stage of the cell cycle, without any detectable differentiation and DMSO itself was found to prevent apoptosis. Programmed cell death, or apoptosis, is now thought to be an important regulatory process in normal hemopoiesis and in the lymphoid system this program is started in the immune process such as autoreactive T-cell elimination in the thymus, and antigen-driven B-cell selection in the terminal centre. For this purpose, we have analysed the effect of DMSO using undifferentiated pre-B (KM-3) and pre-T (RPMI-8402) human lymphoid cells. Results obtained by multiparametric analyses show that DMSO affect only the pre-T cell line inducing a reversible G1 arrest of the cell cycle with a significant presence of apoptotic cells and modification of terminal transferase (TdT) expression. Pre-B cell line is resistant to DMSO treatment. These data provide evidence of a new model for the study of the selective cell type depending effect of DMSO in the immune system.