Multi-omics integrated analysis reveals a specific phenotype of CD8+ T cell may contribute to immunothromosis via Th17 response in severe and critical COVID-19

T lymphocyte reduction and immunosenescence frequently occur in severe and critical coronavirus disease 2019 (COVID-19) patients, which may cause immunothrombosis and numerous sequelae. This study integrated analyzed multi-omics data from healthy donors, pneumonia, COVID-19 patients (mild & moderate, severe, and critical), and convalescences, including clinical, laboratory test, PBMC bulk RNA-seq, PBMC scRNA-seq and TCR-seq, BAL scRNA-seq, and lung proteome. We revealed that there are certain associations among T lymphocyte reduction, CD8+ T cell senescence, Th17 immune activation, and immunothrombosis. A specific phenotype (S. P.) CD8+ T cells were identified in severe and critical COVID-19 patients in both PBMC and BAL scRNA-seq, which showed highly TCR homology with terminal effector CD8+ T cells and senescent CD8+ T cells. Pseudotime analysis showed that the S. P. CD8+ T cells were located in the transition trajectory from mild to severe disease. Which may be activated by terminal effector CD8+ T cells or senescent CD8+ T cells, thereby promoting Th17 cell differentiation. This phenomenon was absent in healthy donors, mild and moderate COVID-19 patients, or convalescences. Our findings are an important reference for avoiding the conversion of patients with mild to severe diseases and provide insight into the future prevention and control of COVID-19 and its variants.

Primary culture of human malignant meningioma cells and its intracranial orthotopic transplantation in nude mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To obtain stable primary cultures of human malignant meningioma cells and establish an intracranial in-situ tumor model in nude mice.</p><p><b>METHODS</b>Ten surgical specimens of highly suspected malignant meningioma were obtained with postoperative pathological confirmation. Primary malignant meningioma cells were cultured from the tissues using a modified method and passaged. After identification with cell immunofluorescence, the cultured cells were inoculated into the right parietal lobe of 6 nude mice using stereotaxic apparatus and also transplanted subcutaneously in another 6 nude mice. The nude mice were executed after 6 weeks, and HE staining and immunohistochmistry were used to detect tumor growth and the invasion of the adjacent brain tissues.</p><p><b>RESULTS</b>The primary malignant meningioma cells were cultured successfully, and postoperative pathology reported anaplastic malignant meningioma. Cell immunofluorescence revealed positivity for vimentin and EMA in the cells, which showed a S-shaped growth curve in culture. Flow cytometry revealed a cell percentage in the Q3 area of (95.99∓2.58)%. Six weeks after transplantation, tumor nodules occurred in the subcutaneous tumor group, and the nude mice bearing the in situ tumor showed obvious body weight loss. The xenografts in both groups contained a mean of (36∓5.35)% cells expressing Ki-67, and the intracranial in situ tumor showed obvious invasion of the adjacent peripheral brain tissues.</p><p><b>CONCLUSION</b>We obtained stable primary cultures of malignant meningioma cells and successfully established a nude mouse model bearing in situ human malignant meningioma.</p>