Sepsis is a leading cause of mortality in intensive care unit worldwide, it's accompanied by immune cell dysfunction induced by multiple factors. However, little is known about the specific alterations in immune cells in the dynamic pathogenesis of sepsis secondary to bacterial pneumonia. Here, we used single cell RNA sequencing (scRNA-seq) to profile peripheral blood mononuclear cells (PBMCs) in a healthy control and two patients with sepsis secondary to bacterial pneumonia, including acute, stable and recovery stage. We analyzed the quantity and function of immune cells. During disease course, interferon gamma response was upregulated; T/NK cell subtypes presented activation and exhaustion properties, which might be driven by monocytes through IL-1β signaling pathways; The proportion of plasma cells was increased, which might be driven by NK cells through IFN signaling pathways; Additionally, interferon gamma response was upregulated in sepsis secondary to pneumonia induced by SARS-COV-2 compared with that induced by influenza virus and bacteria.

As the largest salivary gland in oral cavity, the parotid gland plays an important role in initial digesting and lubricating food. The abnormal secretory function of the parotid gland can lead to dental caries and oral mucosal inflammation. In recent years, single-cell RNA sequencing (scRNA-seq) has been used to explore the heterogeneity and diversity of cells in various organs and tissues. However, the transcription profile of the human parotid gland at single-cell resolution has not been reported yet. In this study, we constructed the cell atlas of human parotid gland using the 10× Genomics platform. Characteristic gene analysis identified the biological functions of serous acinar cell populations in secreting digestive enzymes and antibacterial proteins. We revealed the specificity and similarity of the parotid gland compared to other digestive glands through comparative analyses of other published scRNA-seq data sets. We also identified the cell-specific expression of hub genes for Sjögren syndrome in the human parotid gland by integrating the results of genome-wide association studies and bulk RNA-seq, which highlighted the importance of immune cell dysfunction in parotid Sjögren syndrome pathogenesis.

Introduction:The incidence, mortality, and treatment costs of sepsis are high and, thus, present a major challenge for critical care medicine. Our previous studies suggest that intestinal metabolite granisetron has a potential therapeutic effect on sepsis. Granisetron is a clinically widely used antiemetic, which is safe, inexpensive, and reliable. However, its value in the treatment of sepsis remains unclear. This study aims to explore the efficacy and safety of granisetron in the treatment of sepsis.Methods and analysis:A single-center, single-blind, randomized, controlled clinical trial will be conducted on 154 patients with sepsis. Patients who meet sepsis 3.0 diagnostic criteria, aged ≥18 and ≤80 years, with PCT ≥ 2 ng/mL will be recruited. Patients will be randomized to receive intravenous granisetron 3 mg every 8 hours (n = 77) or an equal volume of normal saline (n = 77) for a treatment period of 4 days or to ICU discharge. The primary outcome is 28-day all-cause mortality. Secondary outcome measures include requirements for organ function support, changes of organ function, changes in infection biomarkers, changes in inflammatory and immune biomarkers, and the proportion of new organ failure. Adverse events and serious adverse events also will be observed closely.Ethics and dissemination:The study was approved by the Clinical Ethics Committee of Zhujiang Hospital of Southern Medical University (2018-ZZJHZX-009). The trial results will be disseminated at national and international conferences and through peer-reviewed journal.Trial registration:NCT03924518.URL: www.clinicaltrials.gov.Protocol date:1 May 2019. version 2.1.