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.
Department of Medicine, University of California, San Francisco, Calif., USA.
Nilceia
N
Lopez-Souza
Silvio
S
Favoreto
Hofer
H
Wong
Theresa
T
Ward
Shigeo
S
Yagi
David
D
Schnurr
Walter E
WE
Finkbeiner
Gregory M
GM
Dolganov
Jonathan H
JH
Widdicombe
Homer A
HA
Boushey
Pedro C
PC
Avila
D000328:Adult; D001249:Asthma / Q000276:immunology / Q000821:virology*; D001980:Bronchi / Q000276:immunology / Q000821:virology*; D002478:Cells, Cultured; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D005260:Female; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009296:Nasal Cavity / Q000276:immunology / Q000821:virology*; D010850:Picornaviridae Infections / Q000276:immunology*; D020545:Respiratory Mucosa / Q000276:immunology / Q000821:virology*; D012229:Rhinovirus; D014779:Virus Replication
D016207:Cytokines; D018799:Intercellular Adhesion Molecule-1