Monitoring of tumor necrosis factor therapy with neopterin.

As neopterin is only secreted by stimulated macrophages, serum neopterin levels are an important marker for cellular immunity. Daily determinations of serum neopterin were performed in five patients with advanced colorectal carcinoma receiving a therapy with tumor necrosis factor (TNF). 24 h after every TNF infusion a significant, but only short-lasting increase of neopterin was observed. This effect was dependent on the applicated TNF dose. These results prove that determinations of serum neopterin levels are a helpful parameter for monitoring an immunomodulating therapy with TNF.