title: The Functional IgE-Blocking Factor Induced by Allergen-Specific Immunotherapy Correlates with IgG4 Antibodies and a Decrease of Symptoms in House Dust Mite-Allergic Children.
abstract: BACKGROUND
  At present, there are no validated biomarkers reflecting or predicting the clinical efficacy of allergen-specific immunotherapy (AIT) . We aimed to investigate the correlations between clinical and immunological responses of patients undergoing house dust mite (HDM) AIT.
  
  
  METHODS
  Sixty-nine children diagnosed with HDM allergic rhinitis and/or asthma received standardized Dermatophagoides pteronyssinus (Dp) subcutaneous AIT for 12 months. Twenty HDM-allergic children served as an open control group. Clinical symptom and medication scores were recorded and Dp-specific IgE, IgG4 and IgE-blocking factor were measured before AIT and after 4 and 12 months of AIT.
  
  
  RESULTS
  Symptom scores decreased after 4 months and continued to decrease during 12 months of AIT. No differences in medication scores were observed between AIT and the control group during the study period. Levels of Dp IgG4 increased after 4 months and correlated to symptom scores at 12 months (r = -0.296, p = 0.013) of AIT. The Dp IgE-blocking factor increased after 4 months of AIT, and correlated with symptom scores at 4 months (r = -0.307, p = 0.010) and 12 months (r = -0.288, p = 0.016) of AIT. A strong correlation between Dp IgE-blocking factor and Dp IgG4 during AIT (4 months: r = 0.680; 12 months: r = 0.636, both p < 0.0001) was observed. Patients with IgE-blocking factor ≥0.2 after 4 months of AIT showed lower symptom scores at 12 months of AIT (p = 0.0093).
  
  
  CONCLUSIONS
  Subcutaneous HDM AIT results in a decrease of allergic symptoms among HDM-allergic children. IgE-blocking activity increased after 4 months of AIT and correlated with clinical symptoms. A high IgE-blocking factor at an early stage of AIT is associated with fewer symptoms at a later stage of AIT.
authors.affiliation: Respiratory Department, The Affiliated Nanjing Children's Hospital of Nanjing Medical University, PR China.
authors.forename: Deyu
authors.initials: D
authors.lastname: Zhao
authors.forename: Xuxin
authors.initials: X
authors.lastname: Lai
authors.forename: Man
authors.initials: M
authors.lastname: Tian
authors.forename: Yanhe
authors.initials: Y
authors.lastname: Jiang
authors.forename: Yiwu
authors.initials: Y
authors.lastname: Zheng
authors.forename: Birgitte
authors.initials: B
authors.lastname: Gjesing
authors.forename: Nanshan
authors.initials: N
authors.lastname: Zhong
authors.forename: Michael D
authors.initials: MD
authors.lastname: Spangfort
mesh_terms: D000293:Adolescent; D000818:Animals; D039741:Antigens, Dermatophagoides / Q000276:immunology*; D001249:Asthma / Q000175:diagnosis / Q000276:immunology / Q000628:therapy; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003888:Desensitization, Immunologic / Q000379:methods; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000175:diagnosis / Q000276:immunology* / Q000628:therapy*; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D008297:Male; D011379:Prognosis; D039981:Pyroglyphidae / Q000276:immunology*; D065631:Rhinitis, Allergic / Q000175:diagnosis / Q000276:immunology / Q000628:therapy; D016896:Treatment Outcome
chemical_list: D039741:Antigens, Dermatophagoides; D007074:Immunoglobulin G; D007073:Immunoglobulin E