Neopterin in Clinical Use

A brief review is given on the value of neopterin determination as a biochemical marker for the in vivo activation state of cell-mediated immunity. In a broad spectrum of diseases which are recognized or supposed to involve activation of monocytes/macrophages by interferon gamma derived from activated T lymphocytes, the applicability and utility of this technically simple test for a variety of specific clinical questions have been demonstrated by a multitude of authors. Applications are e. g. early detection of immunological complications in recipients of allografts, monitoring of inflammatory flare-up in patients with autoimmune disorders, the management of patients with malignant tumours and the monitoring of the clinical course in individuals with various infections and particularly with the human immunodeficiency virus. By measuring levels of neopterin in body fluids, information on the actual state of cell~mediated immunity in vivo is obtained that is not easily achieved by other techniques.