Serum lactoferrin level as a serologic biomarker for allergic rhinitis

P>Background Allergic rhinitis (AR) is a very common disease and a risk factor for allergic asthma. The discovery of new biomarkers for the early detection of AR would improve the clinical outcomes and reduce socio-economic burden. We sought to identify a novel serologic marker for detection of AR using a proteomic approach. Methods To identify the proteins involved in AR, comparative proteomics was applied using nasal lavage fluids (NLFs) taken before and after a nasal provocation test (NPT) with Dermatophagoides pteronyssinus (Dpt) in a subject with AR sensitized to Dpt. The clinical relevance of the identified proteins was evaluated by ELISA using NLFs and sera from the three study groups: Dpt-sensitive AR; asymptomatic Dpt-sensitive controls; and non-atopic healthy controls. The sensitivities and specificities of the candidate proteins for predicting AR were determined using receiver operating characteristic (ROC) curves. Results In proteomic analysis, lactoferrin expression was up-regulated after NPT. The validation study using ELISA showed a significantly lower serum lactoferrin level in the AR group than those of the other two groups (P < 0.05, respectively). To discriminate between subjects with or without AR, the optimal serum cut-off level of lactoferrin was set at < 307 ng/mL using the ROC curve. The sensitivity and specificity for predicting AR were 81.4% and 58%. When combined with serum Dpt-specific IgE level, the sensitivity and specificity for predicting AR were 76.7% and 79.2%. Conclusion These results suggest that the serum lactoferrin level is associated with the phenotype of Dpt-sensitive AR, and in combination with the serum Dpt-specific IgE level, may be a potential serologic marker for early detection of AR. Cite this as: G.-S. Choi, S.-Y. Shin, J.-H. Kim, H.-Y. Lee, N. S. Palikhe, Y.-M. Ye, S.-H. Kim and H.-S. Park, Clinical & Experimental Allergy, 2010 (40) 403-410.