Rhinovirus Growth in Nasal Polyp Organ Culture 51

Little information on the pathophysiology of rhinovirus infection of the respiratory tract is available. The mechanisms by which the symptoms associated with rhinoviral colds are produced and the events which initiate recovery from colds are not known. Since human rhinoviruses do not grow in subprimates, a practical animal model for studying rhinoviral disease is unavailable. Organ culture, an alternative system, has been tried using human fetal tissue 1 2 3 4 but this material is in short supply. The behavior of bovine rhinoviruses has been studied in bovine tracheal organ cultures by Reed and Boyde 5 .

This report describes the development of an organ culture system for growing rhinoviruses in human nasal polyps which are readily available from elective polypectomies. The technique provides a means for studying rhinovirus pathogenesis in human tissue.

Materials and methods. Cultures of nasal polyp fragments. Nasal polyps from patients undergoing elective polypectomy were placed in Hanks' balanced salt solution (HBSS) containing penicillin (100 units/ ml), streptomycin (100 μg/ml), and myco-statin (50 μg/ml) for transport to the laboratory. Within 24 hr of removal, polyps were rinsed with two changes of HBSS, and the mucosa was cut into small pieces approximately 2 mm on a side. Three to five fragments were placed in a screw-capped tube containing 1.0 ml of Leibowitz (L-15) medium [Grand Island Biological Company, Grand Island, New York] with 10% fetal calf serum, 100 units of penicillin, 100 μg of streptomycin, and 50 μg of mycostatin/ml. Tubes were incubated at 34° in a roller drum turning at 10 revolutions/hr. Medium was changed every 3 days until the fragments were infected or used in an experiment as a control.

Fragments which were floating in the medium were examined microscopically at 48 hr for evidence of ciliary motion on the surface.