Interferon production by human cells in vitro

Glutamine addiction in virus-infected mammalian cells: A target of the innate immune system?

Control of core cell metabolism is a key aspect of the evolutionary conflict between viruses and the host's defence mechanisms. From their side, the invading viruses press the accelerator on their host cell's glycolysis, fatty acid, and glutaminolytic metabolic processes among others. It is also well established that activation of innate immune system responses modulates facets of metabolism such as that of polyamine, cholesterol, tryptophan and many more. But what about glutamine, a proteogenic amino acid that is a crucial nutrient for multiple cellular biosynthetic processes? Although mammalian cells can normally synthesize glutamine de novo, it has been noted that infections with genetically and phylogenetically diverse viruses are followed by the acquisition of a dependency on supplies of exogenous glutamine i.e. "glutamine addiction". Here we present our novel hypothesis that glutamine metabolism is also a target of the innate immune system, possibly through the action of interferons, as part of the evolutionary conserved antiviral metabolic reprogramming.

Microtiter assay for interferon: microspectrophotometric quantitation of cytopathic effect

This report describes an accurate, reproducible, and efficient microassay for human interferon, using a dye-uptake method to quantitate cytopathogenicity. The antiviral activity was measured by using a Gilford 300-N microsepctrophotometer, with the automatic programmer, sampler, and data lister. Two hundred interferon samples, each in a final volume of 1.0 ml, may be analyzed and recorded in 45 min. The reproducibility of a laboratory reference interferon and the human international reference B 69/19 on two different cell lines, using the model Q Oxford sampler, was found to be excellent, with the standard error of the log10 geometric mean of both references +/- 0.04 to 0.06.