Hsu K H, Friedman H
J Natl Cancer Inst. 1983 May;70(5):965-9.
Friend erythroleukemia cells (FL cells) derived from DBA/2 mice may be induced to differentiate in vitro by addition of dimethyl sulfoxide (DMSO) to the culture medium. Transglutaminase (glutaminyl-peptide gamma-glutamyltransferase, EC 2.3.2.13) (TGase) activity was detected in the lysates of uninduced FL cells and was markedly increased in DMSO-treated cells. DMSO induced TGase activity of differentiating FL cells in a dose-dependent manner over the concentration range 0-280 mM. The increase in TGase activity was observed after 1 day's cultivation of the cells with 280 mM DMSO and continued to 4 days. Another differentiation inducing agent, butyric acid (1.4 mM), was as effective as DMSO in enhancing TGase activity in FL cells. Treatment of controls, a lymphoma cell line and mouse erythrocytes, with DMSO or butyric acid had no effect. These results suggest that the increase in TGase activity in DMSO- or butyric acid-treated FL cells may be related to cell differentiation.