L-Glutamic acid was shown to increase the stability of cells of the HL-60 line of human promyelocyte leukemia to the cytotoxic action of tumor necrosis factor alpha (TNF-alpha) due to the inhibition of apoptotic and NF-kappaB-activating cascades induced by this cytokine. At the same time, L-glutamic acid increases the TNF-alpha-mediated differentiating signal and the accompanying enhancement of the phosphatidylinositol-specific phospholipase C activity. Therefore, it is a promising agent for the reduction of total toxicity and inflammatory processes during treatment with TNF-alpha. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2005, vol. 31, no. 6; see also http://www.maik.ru.