Establishment of well-differentiated camelid airway cultures to study Middle East respiratory syndrome coronavirus

Gultom, M.; Kratzel, A.; Portmann, J.; Stalder, H.; Baetzner, A. C.; Gantenbein, H.; Gurtner, C.; Ebert, N.; Posthaus, H.; Zanolari, P.; Pfaender, S.; Thiel, V.; Dijkman, R.

doi:10.1101/2021.11.10.468038

bioRxiv · 10.1101/2021.11.10.468038

Establishment of well-differentiated camelid airway cultures to study Middle East respiratory syndrome coronavirus

Gultom, M.·Kratzel, A.·Portmann, J.·Stalder, H.·Baetzner, A. C.·Gantenbein, H.·Gurtner, C.·Ebert, N.·Posthaus, H.·Zanolari, P.·Pfaender, S.·Thiel, V.·Dijkman, R.

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Abstract

In 2012, Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in Saudi Arabia and was mostly associated with severe respiratory illness in humans. Dromedary camels are the zoonotic reservoir for MERS-CoV. To investigate the biology of MERS-CoV in camelids, we developed a well-differentiated airway epithelial cell (AEC) culture model for Llama glama and Camelus bactrianus. Histological characterization revealed progressive epithelial cellular differentiation with well-resemblance to autologous ex vivo tissues. We demonstrate that MERS-CoV displays a divergent cell tropism and replication kinetics profile in both AEC models. Furthermore, we observed that in the camelid AEC models MERS-CoV replication can be inhibited by both type I and III interferons (IFNs). In conclusion, we successfully established camelid AEC cultures that recapitulate the in vivo airway epithelium and reflect MERS-CoV infection in vivo. In combination with human AEC cultures, this system allows detailed characterization of the molecular basis of MERS-CoV cross-species transmission in respiratory epithelium.

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Gultom, M., Kratzel, A., Portmann, J., Stalder, H., Baetzner, A. C., Gantenbein, H., Gurtner, C., Ebert, N., Posthaus, H., Zanolari, P., Pfaender, S., Thiel, V., Dijkman, R.. 2021-11-10. Establishment of well-differentiated camelid airway cultures to study Middle East respiratory syndrome coronavirus. https://doi.org/10.1101/2021.11.10.468038

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