In vitro susceptibility to rhinovirus infection is greater for bronchial than for nasal airway epithelial cells in human subjects.

BACKGROUND: Human rhinoviruses (HRVs) characteristically cause upper respiratory tract infection, but they also infect the lower airways, causing acute bronchitis and exacerbating asthma. OBJECTIVE: Our purpose was to study ex vivo the differences in the response to HRV infection of nasal and bronchial epithelial cultures from the same healthy and asthmatic individuals using conditions favoring development of fully differentiated, pseudostratified mucociliary epithelium. METHODS: Cells from the inferior turbinates and bronchial tree of 5 healthy and 6 asthmatic individuals were cultured at an air-liquid interface. Cultures were infected with HRV-16, and after 48 hours, the degree of infection was measured. RESULTS: Baseline median transepithelial resistance was lower in human bronchial epithelial (HBE) cell cultures than in human nasal epithelial (HNE) cell cultures (195 Omega.cm2 [95% CI, 164-252] vs 366 Omega.cm2 [95% CI, 234-408], respectively; P < .01). Virus replicated more easily in HBE cells than in HNE cells based on virus shedding in apical wash (log tissue culture infective dose of 50%/0.1 mL = 2.0 [95% CI, 1.0-2.5] vs 0.5 [95% CI, 0.5-1.5], P < .01) and on a 20- to 30-fold greater viral load and number of infected cells in HBE cell cultures than in HNE cell cultures. The increases in expression of RANTES and double-stranded RNA-dependent protein kinase were greater in HBE cell cultures than in HNE cell cultures, as were the concentrations of IL-8, IL-1alpha, RANTES, and IP-10 in basolateral medium. However, no significant differences between asthmatic and healthy subjects (including IFN-beta1 expression) were found. CONCLUSIONS: Differentiated nasal epithelial cells might have mechanisms of increased resistance to rhinovirus infection compared with bronchial epithelial cells. We could not confirm previous reports of increased susceptibility to HRV infection in epithelial cells from asthmatic subjects.

Polarized cultures of human airway epithelium from nasal scrapings and bronchial brushings.

Airway epithelial cultures are generally derived from tracheas postmortem or from surgical specimens of nasal polyps or turbinates. Scrapings of the mucosal surface have been little used as starting material for cultures because of their low yield of epithelial cells and their contamination with mucous secretions, blood, and underlying connective tissue. For the first time, we report that human airway epithelial cells obtained from nasal scrapings or bronchial brushings can be grown in culture to produce polarized cell sheets suitable for studies of vectorial transport.