Conjunctival epithelial cells resist productive SARS-CoV-2 infection
Robert M. Jackson, Catherine F. Hatton, Jarmila Stremenova Spegarova, Μαρία Γεωργίου, Joseph Collin, Emily Stephenson, Bernard Verdon, Iram Haq, Rafiqul Hussain, Jonathan Coxhead, Hardeep-Singh Mudhar, Bart Wagner, Megan Hasoon, Tracey Davey, Paul Rooney, C. M. Anjam Khan, Chris Ward, Malcolm Brodlie, Muzlifah Haniffa, Sophie Hambleton, Lyle Armstrong, Francisco C. Figueiredo, Rachel Queen, C.J. Duncan, Majlinda Lako
Abstract
Conjunctival epithelial cells, which express viral-entry receptors angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine type 2 (TMPRSS2), constitute the largest exposed epithelium of the ocular surface tissue and may represent a relevant viral-entry route. To address this question, we generated an organotypic air-liquid-interface model of conjunctival epithelium, composed of basal, suprabasal, and superficial epithelial cells, and fibroblasts, which could be maintained successfully up to day 75 of differentiation. Using single-cell RNA sequencing (RNA-seq), with complementary imaging and virological assays, we observed that while all conjunctival cell types were permissive to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome expression, a productive infection did not ensue. The early innate immune response to SARS-CoV-2 infection in conjunctival cells was characterised by a robust autocrine and paracrine NF-κB activity, without activation of antiviral interferon signalling. Collectively, these data enrich our understanding of SARS-CoV-2 infection at the human ocular surface, with potential implications for the design of preventive strategies and conjunctival transplantation.