Type III interferons are critical host factors that determine susceptibility to Influenza A viral infection in allergic nasal mucosa.

BACKGROUND: Allergic respiratory conditions have been associated with increased susceptibility to viral infection due to impaired interferon (IFN)-related immune responses, but the mechanisms for reinforcement of mucosal immunity against viral infection in allergic diseases are largely unknown. OBJECTIVES: To determine whether IFN induction would be impaired in allergic nasal mucosa and to identify whether higher loads of influenza A virus (IAV) in allergic nasal mucosa could be controlled with IFN treatment. METHODS: Influenza A virus mRNA, viral titres and IFN expression were compared in IAV-infected normal human nasal epithelial (NHNE, N = 10) and allergic rhinitis nasal epithelial (ARNE, N = 10) cells. We used in vivo model of allergic rhinitis (BALB/c mice, N = 10) and human nasal mucosa from healthy volunteers (N = 72) and allergic rhinitis patients (N = 29) to assess the induction of IFNs after IAV infection. RESULTS: Influenza A virus mRNA levels and viral titres were significantly higher in ARNE compared with NHNE cells. IFN-ß and IFN-λs were induced in NHNE and ARNE cells up to 3 days after IAV infection. Interestingly, induction of IFN-λs mRNA levels and the amount of secreted proteins were considerably lower in ARNE cells. The mean IFN-λs mRNA level was also significantly lower in the nasal mucosa of AR patients, and we found that recombinant IFN-λ treatment attenuated viral mRNA levels and viral titres in IAV-infected ARNE cells. In vivoAR mouse exhibited higher viral load after IAV infection, but intranasal inoculation of IFN-λ completely decreased IAV protein expression and viral titre in nasal mucosa of IAV-infected AR mouse. CONCLUSION: Higher susceptibility of the allergic nasal mucosa to IAV may depend on impairment of type III IFN induction, and type III IFN is a key mechanistic link between higher viral loads and control of IAV infection in allergic nasal mucosa.

Changes of nasal function after temperature-controlled radiofrequency tissue volume reduction for the turbinate.

OBJECTIVES: Temperature-controlled and temperature-monitored radiofrequency tissue volume reduction (RFTVR) for the turbinate is a new treatment modality for nasal obstruction secondary to turbinate hypertrophy. We compared the nasal functions after the treatment ofRFTVR and laser vaporizing turbinoplasty (LVT) using subjective symptom scores and objective tests. STUDY DESIGN: Prospective, randomized clinical trial. METHODS: Twenty-four patients with nasal obstruction secondary to inferior turbinate hypertrophy were prospectively evaluated from March 1999 to October 1999 at Seoul National University Hospital (Seoul, Korea). Sixteen patients were treated with RFTVR, and eight patients with LVT. The preoperative and postoperative nasal functions were investigated by visual analogue scale of symptoms, butanol threshold test, saccharine test, acoustic rhinometry, rhinomanometry, and ciliary beat frequency. RESULTS: At 8 weeks postoperatively, the severity and the frequency of nasal obstruction improved subjectively in 81.3% and 93.8% of RFTVR group and in 87.5% and 87.5% of LVT group, respectively. Significant improvement of nasal symptoms began from 2 to 3 days after the operation in the RFTVR group, whereas there was significant improvement of nasal symptoms at 8 weeks after operation in the LVT group. However, objective nasal functions including nasal volume and total nasal resistance were significantly improved at 8 weeks after surgery in both groups. Among patients reporting symptoms of hyposmia, 55.6% of RFTVR group and 63.6% of LVT group showed improved olfaction. Saccharin transit time and ciliary beat frequency were preserved after RFTVR CONCLUSION: RFTVR for the turbinate may be useful as an alternative approach for the treatment of chronic turbinate hypertrophy.