BDNF as a biomarker for evaluating clinical response in allergic rhinitis patients undergoing allergen-specific...

The present study aimed to compare the correlation between serum brain-derived neurotrophic factor (BDNF) level and clinical, immunological parameters in patients receiving allergen-specific subcutaneous immunotherapy (SCIT) for 3 years duration.

Comparing serum BDNF levels in AR patients and healthy controls, the correlation between serum BDNF level and clinical parameters in AR patients was analyzed further. Immunological parameters, including total IgE, d1 sIgE and d2 sIgE, serum BDNF levels, and the clinical parameters were evaluated at the 4-time points that including before immunotherapy, the end of the 1st, 2nd, and 3rd year during the SCIT treatment for AR patients who received immunotherapy.

We found a significantly elevated expression level of serum BDNF levels in AR patients and it also showed a significant correlation with nasal symptom score that included itching score, nasal obstruction score, runny nose, total nasal symptom score, and peripheral parameters including eosinophil percent and eosinophil count. For AR patients who received immunotherapy, a good response was shown, the expression of serum BDNF levels showed a downward trend during 3 years of SCIT, and it significantly positively correlated with the improvement of nasal symptoms including nasal obstruction, nasal itching, and medicine score.

Serum BDNF level was associated with clinical severity in AR patients and clinical parameters in AR patients in SCIT duration, which should be considered as a response evaluation biomarker to monitor clinical efficacy in allergen-specific immunotherapy.