LOCALIZATION OF HUMAN RHINOVIRUS REPLICATION IN THE UPPER RESPIRATORY-TRACT BY IN-SITU HYBRIDIZATION

To localize the sites and determine the extent of human rhinovirus (HR V) replication in the upper respiratory tract, biopsies of nasal and n asopharyngeal epithelia were collected from 26 HRV- or 7 sham-inoculat ed volunteers on days 1, 3, and 5 and on days 12, 20, or 33 after inoc ulation and analyzed by in situ hybridization, HRV-infected cells were detected on at least 1 day in 22 of the 23 HRV-infected subjects and in 1 of the 7 sham-inoculated subjects who developed a cold and had na sal secretions positive for a picornavirus by polymerase chain reactio n. Low numbers of in situ hybridization-positive ciliated cells were p resent in nasal biopsies, In the nasopharynx, most HRV-infected cells were ciliated, but infected nonciliated epithelial cells were also det ected, Our results indicate that HRV replicates in a very small propor tion of cells in the nasal epithelium and in both ciliated and noncili ated cells in the nasopharynx of experimentally infected humans.