Virus- and Interferon Alpha-Induced Transcriptomes of Cells from the Microbat Myotis daubentonii

Hölzer, Martin; Schoen, Andreas; Wulle, Julia; Müller, Marcel A.; Drosten, Christian; Marz, Manja; Weber, Friedemann

Not all these genes are known as pure virus responders. Therefore, we verified our findings by RT-qPCR for the strongest early virus responders (IFNB1, CCL4, IFNL3, CH25H, STEAP4) and compared with the human system. Although being a late responder, CH25H (cholesterol 25-hydroxylase) is included because it is a powerful, broad-spectrum virus inhibitor. Human A549 and MyDauNi cells were infected with Clone 13, treated with IFN, or left untreated, and samples were taken 6 and 24 h later. Moreover, to exclude any potential cross talk by virus-triggered IFN, we kept in parallel cells under the JAK/STAT signaling inhibitor Ruxolitinib. In both the human and the Myotis cells, Ruxolitinib expectedly inhibited STAT1 phosphorylation and upregulation of the prototypical IFN-dependent ISG Mx1 ( Figure S7 ). The RT-qPCR data shown in Figure 5 demonstrate that IFNB1, CCL4, IFNL3, and CH25A are exclusively virus induced with no stimulation whatsoever by IFN. (Of note, a downmodulation of IFNB1 at 24 h post infection was detected by RT-qPCR but not by the less sensitive NGS [see Figure 2 ].) This was true for both the human and the M. daubentonii cells, indicating a conserved behavior. STEAP4 (six transmembrane epithelial antigen of prostate), by contrast, was identified as a virus-only response gene in M. daubentonii cells but unresponsive to both IFN and Clone 13 in human cells.