Antimycoplasma Properties and Application in Cell Culture of of the biological reagent Mynox

Mycoplasma contamination of cell cultures is a serious and widespread problem. Contaminated cultures are frequently discarded or the contamination ignored since treatment with standard antibiotics is undesirable, time-consuming, and an ineffective means to eliminate mycoplasmas. Minerva Biolabs developed an innovative methode based on the biological reagent Mynox. A single treatment over one passage led to complete removal of viable Mycoplasma hyorhinis cells from various adherent cell lines, and Mycoplasma orale was removed from nonadherent human T-lymphoid cell lines by a single treatment. This effect was monitored by a DNA fluorescence test, an enzyme-linked immunosorbent assay, and two different PCR methods. Disintegration of the mycoplasma membranes as observed by electron microscopy indicated the mode of action of Mynox. Disintegration is obviously due to a physicochemical interaction of the membrane-active Mynox with the outer part of the lipid membrane bilayer, which causes permeability changes and at higher concentrations leads finally to disintegration of the mycoplasma membrane system. The low cytotoxicity of Mynox for mammalian cells permits specific inactivation of mycoplasmas without significant deleterious effects on cell metabolism and the proliferation rate in cell culture. A fast and simple method for complete and permanent inactivation of mycoplasmas in mammalian monolayer and suspension cell cultures is described.