Sublingual immunotherapy may affect serum neopterin: preliminary findings.

Neopterin is a protein produced by monocytes/macrophages. It has been considered a biomarker of immune activation in several disorders. However, there are few studies in allergic rhinitis (AR). This study evaluated the serum neopterin levels in patients with pollen-induced AR or treated with sublingual immunotherapy (SLIT) and in healthy subjects.146 subjects (70 males, median age 30.5 years): 56 with moderate-severe persistent AR, 40 with AR and successfully treated with 2 year SLIT, and 50 healthy controls were consecutively evaluated outside the pollen season. A skin prick test and blood sampling for assessing serum neopterin levels were performed in all subjects.SLIT-treated patients had lower neopterin levels than untreated patients and healthy subjects (respectively p=0.012 and p=0.0001).Neopterin is a biomarker for immune activation, SLIT may affect serum neopterin probably as a consequence of Treg response to SLIT.