Neopterin as a marker of cellular immunological response

Abstract

Neopterin is a pyrazino-pyrimidine compound that belongs to the pteridine group. It is known to be a biochemical marker associated with cell-mediated immunity. It is produced by human monocytes/macrophages and dendritic cells from guanosine triphosphate (GTP) upon stimulation with interferon gamma (IFNγ), which is released by activated limphocytes Th. Neopterin is a very important clinic parameter, though the physiological role has not been exactly definited thus far. The level of neopterin reflects the stage of activation of the cellular immune system, which is important in the pathogenesis and progression of various diseases. Measuring its concentration in body fluids is used in many different areas of modern medicine, such as infectious disease, gastroenterology, transplantology and transfusiology, rheumatology or oncology. In neurological, cardio-vascular and autoimmune diseases, cell-mediated immunity is also activated, which is proved by the elevated level of this marker. Measurements of neopterin concentrations are also helpful in monitoring the therapy of patients infected with the HIV virus or treated by using immunomudulating therapy. As a result of measuring levels of neopterin in patients with neoplasms of digestive tract, increased concentration was proved, but it is not routinely used in everyday clinic practice.

Neopterin levels and Kyn/Trp ratios were significantly increased in dengue virus patients and subsequently decreased after recovery

“…shown to be associated with longer fever duration and the severity of inflammation (Chan et al, 2006), our results indicate a strong correlation of neopterin and Kyn/Trp ratio over a period of nearly 10 days, starting from the time of first diagnosis at the hospital until convalescence. Neopterin is produced by activated monocytes, macrophages, and DCs upon stimulation by IFN-g and has been a useful marker for cellular immune activation (Michalak et al 2017) and for monitoring infectious disease activity during treatment. Elevated neopterin levels have been associated with various infectious diseases including viral infections and cancers (Chan et al, 2006;Sucher et al, 2010;Widner et al, 2002).…”

Age associated microbiome modulation and its association with systemic inflammation in a Rhesus Macaque Model

“…Increases in IL-6, IFNγ, and TNFα are expected as these are known inflammatory cytokines that act on a systemic level, promoting chronic inflammation that’s associated with age (25). Increased CRP and neopterin are indicative of an increased systemic immune activation inflammatory state in older animals (26, 27). Neopterin, a metabolite of GTP, is produced in macrophages upon stimulation by IFNg released by activated T cells indicating an ongoing immune system activation and inflammatory response in the older animals.…”

Diverse Responses of Neurons and Monocytes to Titanium Dioxide Nanoparticle Exposure

“…Although not routinely used in daily clinical practice, activation of cell-mediated immunity is demonstrated by high neopterin levels in neurological, cardio-vascular, malignant and autoimmune diseases. [71,72,73] In addition, measurements of neopterin concentrations are helpful in monitoring the immune modulating therapy of patients. [73] However, no toxicity has been reported due to endogenous overexpression of neopterin.…”

“…[71,72,73] In addition, measurements of neopterin concentrations are helpful in monitoring the immune modulating therapy of patients. [73] However, no toxicity has been reported due to endogenous overexpression of neopterin. In our study, it was tested whether neopterin, which is synthesized by the activated macrophages, had an antioxidant effect in the environment without macrophages.…”