Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.07.23.217703v1?rss=1 Authors: Wang, F.-S., Zhang, J.-Y., Wang, X., Xing, X., Xu, Z., Zhang, C., Song, J.-W., Fan, X., Xia, P., Fu, J.-L., Wang, S.-Y., Xu, R.-N., Dai, X.-P., Shi, L., Huang, L., Jiang, T.-J., Shi, M., Zhang, Y., Zumla, A., Maeurer, M., Bai, F. Abstract: In COVID-19 caused by SARS-CoV-2 infection, the relationship between disease severity and the host immune response is not fully understood. Here we performed single-cell RNA sequencing in peripheral blood samples of five healthy donors and 13 COVID-19 patients including moderate, severe and convalescent cases. Through determining the transcriptional profiles of immune cells, coupled with assembled T cell receptor and B cell receptor sequences, we analyzed the functional properties of immune cells. Most cell types in COVID-19 patients showed a strong interferon-alpha response, and an overall acute inflammatory response. Moreover, intensive expansion of highly cytotoxic effector T cell subsets, such as CD4+ Effector-GNLY (Granulysin), CD8+ Effector-GNLY and NKT CD160, was associated with convalescence in moderate patients. In severe patients, the immune landscape featured a deranged interferon response, profound immune exhaustion with skewed T cell receptor repertoire and broad T cell expansion. These findings illustrate the dynamic nature of immune responses during the disease progression. Copy rights belong to original authors. Visit the link for more info