Fig. 7: Confirmation of the protective effect of sMV@GEL against H1N1 viral aerosols by using the human respiratory tract model.

a Schematic diagram of the experimental design. We used the CT data from the volunteer and 3D printing technology to fabricate a realistic human nasal apparatus. Meanwhile, we cultured human lung organoids from the paracancerous tissue of a lung cancer patient. To imitate the human respiratory tract (HRT), we constructed an integrated HRT model by placing the lung organoids into a container with the following vents: one vent was connected to the nasal apparatus via a sterile tube, and the other was connected to a pump for providing respiratory airflow. b Full-view photograph of the integrated HRT model and magnified photographs of three important modules, showing the inhalation of the viral aerosols near the nasal apparatus (red frame), the airflow control by a pump (blue frame), and the lung organoids container for infection detection (green frame). c CLSM images showing FOXJ1 (ciliated cell marker), SCGB1A1 (club cell marker), P63 (basal cell marker), and SA (H1N1 receptor) expression in paracancerous tissue (upper) and lung organoids (lower). FOXJ1, SCGB1A1, and P63 were stained with corresponding antibodies and secondary Alexa Fluor® 647 fluorescent antibody, SA was stained with Cy3-SNL (red, false color). White: FITC-phalloidine stained cytoskeleton; Blue: DAPI stained cell nuclei. d Representative 3D reconstructed CLSM images of lung organoids in different groups after 24 h or 48 h of challenge with H1N1-CA07 aerosols. White: FITC-phalloidine stained cytoskeleton; Blue: DAPI stained cell nuclei. Green: the fluorescent antibody-stained N protein of H1N1-CA07. e Relative level of H1N1-CA07 mRNA in lung organoids of different groups after 24 h or 48 h of challenge with H1N1-CA07 aerosols. f Relative level of H1N1-PR8 mRNA in lung organoids of different groups after 24 h or 48 h of challenge with H1N1-PR8 aerosols. Data in e and f represent the means ± S.E.M., n = 3 biologically independent experiments. Statistical significance in e and f was tested with two-tailed unpaired t-test. All significant P-values are indicated. Source data are provided in the Source data file.