Neopterin
Neopterin is a low molecular weight molecule belonging to the chemical group known as pteridines. It is synthesised by cellular immune reaction of macrophages and dendritic cells upon stimulation with the cytokine interferon-g and as a consequence released. Neopterin has a higher stability in body fluids which makes the sample handling and measurement easier compared to other cytokines. Neopterin biosynthesis is closely associated with activation of the cellular immune system. Increased concentrations of neopterin were reported in individuals with viral infections, suggesting that increased values may originate from the immune response of individuals directed against virally infected cells. It was shown that antigenic stimulation of human peripheral blood mononuclear cells leads to neopterin release into cell culture medium and that human macrophages produce neopterin in vitro when stimulated by interferon gamma.
