Elisa kit 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. The low molecular weight, let neopterin molecules rapidly pass the intravasal area, where it is releases in urine after glomerular filtration. The half life period in human bodies is only affected by renal excretion. So neopterin values reflect the totality of immunological processes for monocytes/macrophages and dendritic cells and can be seen as a general marker of immune activity. This characteristic feature of neopterin to reflect the different interactions of immunocompetent cells is the basis for the extraordinary status of measuring neopterin in immunological diagnosis. As a non-invasive method, urinary neopterin to creatinine ratio determination is also helpful in monitoring disease progression and the effects of therapies, as well.
Neopterin biosynthesis is closely associated with activation of the cellular immune system. Increased concentrations of neopterin were reported in patients with viral infections, suggesting that increased values may originate from the immune response of patients 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.
The determination of neopterin levels in human body fluids offers a useful and innovative tool to monitor
diseases associated with the activation of cell-mediated immunity.
Increasing neopterin levels in various infections precede the clinical manifestation and seroconversion.
Normally samples are not tested for all possible infections. Therefore, the measurement of neopterin in
blood donor samples is a useful tool in order to reduce the risk of infections via blood transfusion.
Other diagnostic applications for the determination of neopterin are:
- follow-up of traumatized ICU patients
- use as prognostic indication in HIV infections and malignant diseases
- early indication of complications in allograft recipients
- indication of disease activity in autoimmune diseases
- diagnosis of viral infections
- differential diagnosis of acute viral and bacterial infections
- diagnosis of tumour diseases
- follow-up control of chronic infections and monitoring of immunostimulatory therapy