Single-cell transcriptional atlas of the Chinese horseshoe bat (Rhinolophus sinicus) provides insight into the cellular mechanisms which enable bats to be viral reservoirs

Bats are a major "viral reservoir" in nature and there is a great interest in not only the cell biology of their innate and adaptive immune systems, but also in the expression patterns of receptors used for cellular entry by viruses with potential cross-species transmission. To address this and other questions, we created a single-cell transcriptomic atlas of the Chinese horseshoe bat (Rhinolophus sinicus) which comprises 82,924 cells from 19 organs and tissues. This atlas provides a molecular characterization of numerous cell types from a variety of anatomical sites, and we used it to identify clusters of transcription features that define cell types across all of the surveyed organs. Analysis of viral entry receptor genes for known zoonotic viruses showed cell distribution patterns similar to that of humans, with higher expression levels in bat intestine epithelial cells. In terms of the immune system, CD8+ T cells are in high proportion with tissue-resident memory T cells, and long-lived effector memory nature killer (NK) T-like cells (KLRG1, GZMA and ITGA4 genes) are broadly distributed across the organs. Isolated lung primary bat pulmonary fibroblast (BPF) cells were used to evaluate innate immunity, and they showed a weak response to interferon {beta} and tumor necrosis factor- compared to their human counterparts, consistent with our transcriptional analysis. This compendium of transcriptome data provides a molecular foundation for understanding the cell identities, functions and cellular receptor characteristics for viral reservoirs and zoonotic transmission.

Rapid construction of stable cell lines which inducible express HA proteins from various influenza virus strains / 中华实验和临床病毒学杂志

Objective@#An innovative technique was established to rapidly construct various cell lines that could be induced to express multiple influenza A virus (IAV) proteins.@*Method@#The HA protein genes of multiple IAVs were cloned into the Cumate-induced expression system which was positioned between two PiggyBac transposon sites. These HA plasmids were transfected into the HEK293A cell line with the PiggyBac transposase plasmids. The transfected cells were screened with puromycin, and after that the corresponding virus proteins were induced with Cumate.@*Results@#The results of flow cytometry and Western blotting showed that the virus proteins were expressed in most of the cells in corresponding lines after the induction of Cumate.@*Conclusion@#Cell lines which were inducible to express IVA HA protein can be efficiently constructed by using the PiggyBac transposon system.