A primary nasopharyngeal three-dimensional air-liquid interface cell culture model of the pseudostratified epithelium reveals differential donor- and cell type-specific susceptibility to Epstein-Barr virus infection.

Epstein-Barr virus (EBV) is a ubiquitous γ-herpesvirus with latent and lytic cycles. EBV replicates in the stratified epithelium but the nasopharynx is also composed of pseudostratified epithelium with distinct cell types. Latent infection is associated with nasopharyngeal carcinoma (NPC). Here, we show with nasopharyngeal conditionally reprogrammed cells cultured at the air-liquid interface that pseudostratified epithelial cells are susceptible to EBV infection. Donors varied in susceptibility to de novo EBV infection, but susceptible cultures also displayed differences with respect to pathogenesis. The cultures from one donor yielded lytic infection but cells from two other donors were positive for EBV-encoded EBERs and negative for other lytic infection markers. All cultures stained positive for the pseudostratified markers CK7, MUC5AC, α-tubulin in cilia, and the EBV epithelial cell receptor Ephrin receptor A2. To define EBV transcriptional programs by cell type and to elucidate latent/lytic infection-differential changes, we performed single cell RNA-sequencing on one EBV-infected culture that resulted in alignment with many EBV transcripts. EBV transcripts represented a small portion of the total transcriptome (~0.17%). All cell types in the pseudostratified epithelium had detectable EBV transcripts with suprabasal cells showing the highest number of reads aligning to many EBV genes. Several restriction factors (IRF1, MX1, STAT1, C18orf25) known to limit lytic infection were expressed at lower levels in the lytic subcluster. A third of the differentially-expressed genes in NPC tumors compared to an uninfected pseudostratified ALI culture overlapped with the differentially-expressed genes in the latent subcluster. A third of these commonly perturbed genes were specific to EBV infection and changed in the same direction. Collectively, these findings suggest that the pseudostratified epithelium could harbor EBV infection and that the pseudostratified infection model mirrors many of the transcriptional changes imposed by EBV infection in NPC.

A Nasopharyngeal Carcinoma Patient With COVID-19 Infection After Immunotherapy: A Case Report and Literature Review.

BACKGROUND/AIM: Novel coronavirus infection in a cancer patient treated with immunotherapy, requires high attention. CASE REPORT: Clinical and radiological data were obtained from the electronic medical record. Pharynx swab was tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA by reverse transcription-polymerase chain reaction (RT-PCR). The nasopharyngeal carcinoma patient developed fever on the third day after chemotherapy and immunotherapy. Laboratory examination showed lymphocytopenia. On the sixth day, chest computed tomography (CT) images showed bilateral scattered ground-glass opacities and reticulation. Pharynx swab was positive for SARS-CoV-2 nucleic acid and the patient was confirmed as having Coronavirus Disease 2019 (COVID-19). Unfortunately, despite aggressive treatment after the diagnosis of COVID-19, the patient died quickly. CONCLUSION: The patient with nasopharyngeal carcinoma in this case developed severe COVID-19 after receiving immunotherapy. For patients treated with immune checkpoint inhibitors (ICIs) in epidemic areas, the safety of ICIs in cancer patients infected with SARS-CoV-2 should be considered.