RESPIRATORY SYNCYTIAL VIRUS AND HUMAN BRONCHIAL EPITHELIUM

Background: A suitable model for respiratory syncytial virus (RSV) inf ection has yet to be developed. Objective: To describe an in vitro mod el of human respiratory epithelium in primary cell culture linked with a computer microscope interface that allows evaluation and imaging of living RSV-infected respiratory epithelium. Design: A descriptive, co ntrolled study. Human bronchial cells were obtained from surgical samp les by elastase dissociation and replated on collagen gel membranes. A fter 7 to 10 days, cells were brought to air interface. Baseline sampl ing of cell fluid for cytokine production by enzyme-linked immunosorbe nt assay (interleukin [IL] Ip, IL-6, IL-8, and RANTES) and leukotriene C4 by radioimmunoassay was taken before treatment with RSV (n = 30) o r HEp-2 (human laryngeal carcinoma cells) control (n=25). Sampling was done at 4, 24, 72, and 120 hours thereafter. The infectious process w as monitored with a microscope (Zeiss UEM, Carl Zeiss Inc, Thornwood, NY) equipped with a camera (Newvicon, Dage Corporation, Stamford, Conn ). Images were either digitized using a computer (Macintosh Quadra 950 , Apple Computers Inc, Cupertino, Calif) equipped with a digitizing bo ard (Perceptics Corporation, Knoxville, Tenn) or were recorded on an S VHS videotape using a videocassette recorder (JVC, Elmwood Park, NJ). Results: Respiratory syncytial virus induced profound effects on the c iliated cells: ciliostasis, clumping, and loss of cilia from live cell s and sloughing of cells. Significant differences in the release of IL -6, IL-8, and RANTES (P<.03 for each cytokine) were noted in RSV-infec ted bronchial cultures by 24 hours with a peak at 72 hours. The IL-P a nd leukotriene C4 were not altered by RSV infection in bronchial cells . Conclusions: This model closely mirrors human RSV disease and afford s a unique opportunity to study interepithelial cell interactions, cyt okine responses from cells of different donors, and ciliary activity o f live cells undergoing RSV infection.