Macrophage cytostasis and T and B cell blastogenic transformation in mice treated with nystatin

Lipid rafts in T cell signalling and disease

Lipid rafts is a blanket term used to describe distinct areas in the plasma membrane rich in certain lipids and proteins and which are thought to perform diverse functions. A large number of studies report on lipid rafts having a key role in receptor signalling and activation of lymphocytes. In T cells, lipid raft involvement was demonstrated in the early steps during T cell receptor (TCR) stimulation. Interestingly, recent evidence has shown that signalling in these domains differs in T cells isolated from patients with autoimmune diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Here, we discuss these findings and explore the potential of lipid rafts as targets for the development of a new class of agents to downmodulate immune responses and for the treatment of autoimmune diseases.

Identification of novel pharmacological activities of an antifungal agent, nystatin, to promote dendritic cell maturation

As an unbiased functional screen to identify agents activating dendritic cells (DCs), we recently developed a DC-based biosensor system, in which a stable murine DC line XS106 was engineered to express the yellow fluorescent protein (YFP) gene under the control of the IL-1beta promoter. Here we report that nystatin (NYT), an antifungal drug of the family of polyene macrolide antibiotics, elevated YFP expression by the resulting XS106-pIL1-YFP DC biosensor clone in a dose-dependent fashion. With respect to the underlying mechanisms, NYT activated the NFkappaB p65 and c-Rel subunits in the parental XS106 DC line. Moreover, NYT dose-dependently increased the surface expression of major histocompatibility complex (MHC) class II (MHC II), CD40, CD54, CD80, and CD86 by murine bone marrow-derived DCs and triggered their robust production of IL-1beta, IL-6, IL-12, tumor necrosis factor alpha, and macrophage inflammatory protein-1alpha. Our results document previously unrecognized pharmacological activities of the most commonly used antifungal drug to promote DC maturation.

Studies on the action of nystatin on cultured rat myocardial cells and cell membranes, isolated rat hearts, and intact rats

The action of nystatin, a polyene antibiotic, was studied in rat myocardial cells, isolated rat hearts, and intact rats. Myocardial cells responded to 10 and 25 micrograms nystatin/ml with arrhythmias that could be minimized by elevated concentrations of K+ and Mg2+ or reversed by washing the cells. Similarly, the isolated heart responded to 100 micrograms nystatin/ml with arrhythmias that could be tempered by addition of elevated concentrations of K+ and Mg2+. The i.v. injection of the drug caused heart failure in intact animals at the 4-mg/kg dose level. At the subcellular level, nystatin made the myocardial cell membranes more rigid, as measured by electron spin resonance spectrometry. These findings indicate a parallel between physiocochemical changes caused by nystatin in the myocardial cell membrane and the biological changes caused by this drug in myocardial cells, isolated heart, and heart of the intact animal.