No abstract

et al. (2020). Co-infections of SARS-CoV-2 with multiple common respiratory pathogens in infected patients. Sci China Life Sci 63, 606-609. https://doi.

Background: Tuberculosis (TB) continues to be a critical global health problem, which killed millions of lives each year. Certain circulating cell subsets are thought to differentially modulate the host immune response towards Mycobacterium tuberculosis (Mtb) infection, but the nature and function of these subsets is unclear. Methods: Peripheral blood mononuclear cells (PBMC) were isolated from healthy controls (HC), latent tuberculosis infection (LTBI) and active tuberculosis (TB) and then subjected to single-cell RNA sequencing (scRNA-seq) using 10 £ Genomics platform. Unsupervised clustering of the cells based on the gene expression profiles using the Seurat package and passed to tSNE for clustering visualization. Flow cytometry was used to validate the subsets identified by scRNA-Seq. Findings: Cluster analysis based on differential gene expression revealed both known and novel markers for all main PBMC cell types and delineated 29 cell subsets. By comparing the scRNA-seq datasets from HC, LTBI and TB, we found that infection changes the frequency of immune-cell subsets in TB. Specifically, we observed gradual depletion of a natural killer (NK) cell subset (CD3-CD7+GZMB+) from HC, to LTBI and TB. We further verified that the depletion of CD3-CD7+GZMB+ subset in TB and found an increase in this subset frequency after anti-TB treatment. Finally, we confirmed that changes in this subset frequency can distinguish patients with TB from LTBI and HC. Interpretation: We propose that the frequency of CD3-CD7+GZMB+ in peripheral blood could be used as a novel biomarker for distinguishing TB from LTBI and HC.

A novel, rapid and simple fluorescence resonance energy transfer (FRET) based Salmonella specific gene, invA, detection system was developed, in which quantum dots (QDs) and graphene oxide (GO) worked as fluorescent donor and quencher, respectively. By measuring the fluorescence intensity signal, the Salmonella specific invA gene could be sensitively and specifically detected with a limit of detection (LOD) of ∼4 nM of the invA gene in 20 min. The developed system has the potential to be used for Salmonella detection in food and environmental samples and further developed into a platform for detection of other bacterial pathogens.

19The ongoing SARS-CoV-2 outbreak has killed over twenty-one thousand and sickened over four 20 hundred thousand people worldwide, posing a great challenge to global public health. A sensitive and 21 accurate diagnosis method will substantially help to control disease expansion. Here, we developed a 22 chemiluminescence-immunoassay method based on the recombinant nucleocapsid antigen and the 23 magnetic beads for diagnosis of SARS-CoV-2 infections and surveillance of antibody changing pattern. : medRxiv preprint Serums from 29 healthy individuals, 51 tuberculosis patients, and 79 SARS-CoV-2 confirmed patients 25 were employed to evaluate the performance of this approach. Compared to the IgM testing, the IgG 26 testing was more reliable in which it identified 65 SARS-CoV-2 infections from the 79 confirmed 27 patients and only two false-positive cases from the 80 control group with a sensitivity and specificity 28 reaching 82.28% and 97.5%, respectively. However, only a slight difference (not statistically 29 significant) in the detected cases of SARS-CoV-2 infections was observed between the IgM and IgG 30 testing manner in patients at a different time of onset of disease. A performance comparison 31 between an ELISA kit using the same nucleocapsid antigen and our chemiluminescence method was 32 undertaken. The same false-positive cases were seen in both methods from the paired control group, 33 while ELISA kit can only detect half of the SARS-CoV-2 infections from paired SARS-CoV-2 confirmed 34 patients group than that of the chemiluminescence method, indicating a higher performance for the 35 chemiluminescence-immunoassay approach. Together, our studies provide a useful and valuable 36 serological testing tool for the diagnosis of SARS-CoV-2 infections in the community.37