title: Suppression of Immunotherapy on Group 2 Innate Lymphoid Cells in Allergic Rhinitis.
abstract: BACKGROUND
  Group 2 innate lymphoid cells (ILC2s) are regarded as a novel population of lineage-negative cells that induce innate Type 2 responses by producing the critical Th2-type cytokines interleukin (IL)-5 and IL-13. ILC2s as key players in the development of allergic rhinitis (AR) have been proved, however, the effect of subcutaneous immunotherapy (SCIT) with dermatophagoides pteronyssinus extract (Der p-SCIT) on ILC2s in AR patients is not clear. This study aimed to investigate the response of ILC2s of peripheral blood in house dust mites (HDM)-sensitized Chinese patients with AR who received SCIT with Der P extract.
  
  
  METHODS
  Seven healthy controls without symptoms of AR who had negative reactions to any of the allergens from skin-prick testing, nine patients diagnosed with persistent AR according to the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines, and 24 AR patients who received Der p-SCIT for 1.0-3.5 years were recruited for the study. ILC2s in the peripheral blood were evaluated using flow cytometry. The severity of their symptoms of all participants was rated based on the Total 5 symptom score.
  
  
  RESULTS
  Among 40 participants, 9 AR patients were assigned to the untreated group, 24 AR patients receiving Der p-SCIT were assigned to the immunotherapy group, and 7 healthy controls without symptoms of AR were assigned to healthy control group. The mean Total 5 symptom score of immunotherapy group was significantly lower than that of untreated group (4.3 ± 1.4 vs. 10.1 ± 2.5, P< 0.001). Similarly, the levels of ILC2s in the peripheral blood of immunotherapy group were significantly reduced compared with that in untreated group (P < 0.001), but were not significantly different from healthy controls (P = 0.775). Further subgroup analysis based on the duration of SCIT therapy (1.0-2.0 years [SCIT1-2], 2.0-3.0 years [SCIT2-3], and 3.0-3.5 years [SCIT3-3.5]) showed that the percentage of ILC2s was not significantly different between SCIT1-2, SCIT2-3, and SCIT3-3.5groups (SCIT1-2 vs. SCIT2-3: P = 0.268; SCIT1-2vs. SCIT3-3.5: P = 0.635; and SCIT2-3 vs. SCIT3-3.5: P = 0.787).
  
  
  CONCLUSIONS
  The present study highlighted the suppression of Der p-SCIT on ILC2s in HDM-AR patients. ILC2s identified in peripheral blood can be used as an effective biomarker for Der p-SCIT.
authors.affiliation: Department of Otolaryngology Head and Neck Surgery; Department of Allergy, Beijing Tongren Hospital, Capital Medical University, Beijing 100730; Department of Otorhinolaryngology Head and Neck Surgery, The First Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang 150001, China.
authors.forename: Da-Chuan
authors.initials: DC
authors.lastname: Fan
authors.affiliation: Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing 100005, China.
authors.forename: Xiang-Dong
authors.initials: XD
authors.lastname: Wang
authors.affiliation: Department of Otolaryngology Head and Neck Surgery; Department of Allergy, Beijing Tongren Hospital, Capital Medical University, Beijing 100730; Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing 100005, China.
authors.forename: Cheng-Shuo
authors.initials: CS
authors.lastname: Wang
authors.affiliation: Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing 100005, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Otolaryngology Head and Neck Surgery; Department of Allergy, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
authors.forename: Fei-Fei
authors.initials: FF
authors.lastname: Cao
authors.affiliation: Department of Otolaryngology Head and Neck Surgery; Department of Allergy, Beijing Tongren Hospital, Capital Medical University, Beijing 100730; Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing 100005, China.
authors.forename: Luo
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D040002:Dermatophagoides pteronyssinus / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D018793:Interleukin-13 / Q000378:metabolism; D015848:Interleukin-5 / Q000378:metabolism; D008214:Lymphocytes / Q000276:immunology* / Q000378:metabolism; D008297:Male; D065631:Rhinitis, Allergic / Q000276:immunology* / Q000378:metabolism / Q000628:therapy*; D012882:Skin Tests; D063729:Sublingual Immunotherapy; D055815:Young Adult
chemical_list: D018793:Interleukin-13; D015848:Interleukin-5