Predictors and nomogram of in-hospital mortality in sepsis-induced myocardial injury: a retrospective cohort study.

BACKGROUND: Sepsis-induced myocardial injury (SIMI) is a common organ dysfunction and is associated with higher mortality in patients with sepsis. We aim to construct a nomogram prediction model to assess the 28-day mortality in patients with SIMI. . METHOD: We retrospectively extracted data from Medical Information Mart for Intensive Care (MIMIC-IV) open-source clinical database. SIMI was defined by Troponin T (higher than the 99th percentile of upper reference limit value) and patients with cardiovascular disease were excluded. A prediction model was constructed in the training cohort by backward stepwise Cox proportional hazards regression model. The concordance index (C-index), area under the receiver operating characteristics curve (AUC), net reclassification improvement (NRI), integrated discrimination improvement (IDI), calibration plotting and decision-curve analysis (DCA) were used to evaluate the nomogram. RESULTS: 1312 patients with sepsis were included in this study and 1037 (79%) of them presented with SIMI. The multivariate Cox regression analysis in all septic patients revealed that SIMI was independently associated with 28-day mortality of septic patients. The risk factors of diabetes, Apache II score, mechanical ventilation, vasoactive support, Troponin T and creatinine were included in the model and a nomogram was constructed based on the model. The C-index, AUC, NRI, IDI, calibration plotting and DCA showed that the performance of the nomogram was better than the single SOFA score and Troponin T. CONCLUSION: SIMI is related to the 28-day mortality of septic patients. The nomogram is a well-performed tool to predict accurately the 28-day mortality in patients with SIMI.

Interleukin-1ß Protection Against Experimental Sepsis in Mice.

The inflammatory response involving interleukin-1ß (IL-1ß) has been thought to play an important role in the development of late-phase sepsis. However, in this study, we wanted to explore the possibility of using IL-1ß to improve the prognosis of sepsis by triggering local differentiation of bone marrow cells (BMCs) into regulatory dendritic cells (DCs) in vivo, thereby reversing the immune paralysis in late-phase sepsis. Sepsis mouse models were induced by cecal ligation and puncture (CLP) and lethal Escherichia coli O18 infection. Mice were injected intraperitoneally with IL-1ß after CLP and after the lethal infection. Septic BMCs and liver immune cells were isolated at 0, 3, 6, 9, and 14 days post-CLP. BMCs and liver cells isolated from septic mice treated with IL-1ß were adoptively transferred into CLP mice. GFP+-C57BL/6 parabiosis models were established. Serum IL-1ß levels were determined by enzyme-linked immunosorbent assay (ELISA) kit, and the number, ratio, and phenotype of immune cells were observed by flow cytometry. IL-1ß treatment improved the survival of sepsis and increased the numbers of BMCs and liver immune cells in septic mice. Moreover, IL-1ß stimulation increased the number and the percentage of CD11c-CD45RBhigh DCs in septic BM and liver. Adoptive transfer of septic BMCs, liver immune cells, and CD11c-CD45RBhigh DCs treated with IL-1ß into CLP mice attenuated sepsis. IL-1ß triggered the redistribution of CD11c-CD45RBhigh DCs as well as BMCs in parabiosis models. IL-1ß protects against sepsis by stimulating local proliferation and differentiation of BMCs into CD11c-CD45RBhigh DCs at immune organs and non-immune organs.

High Mobility Group Protein 1 Reverses Immune System Paralysis in Late-Phase Sepsis.

High mobility group protein 1 (HMGB1) is considered to be the primary inflammatory factor triggering immune paralysis in late-phase sepsis. In this study, however, we wanted to explore the possibility of using HMGB1 to boost local differentiation of bone marrow cells (BMCs) into regulatory dendritic cells (DCs) in vivo, thereby inducing immune reversal in late-phase sepsis and improving the prognosis. For this purpose, sepsis was induced by cecal ligation and puncture (CLP). Mice were injected intraperitoneally with HMGB1 (10, 50, or 250 µg/kg of body weight) 7 days before CLP. BMCs and liver immune cells were isolated at 0, 3, 5, and 7 days post-CLP. Mice were intranasally infected with Pseudomonas aeruginosa 3 days post-CLP as a secondary pneumonia infection model. BMCs and liver cells isolated from septic mice pretreated with HMGB1 were adoptively transferred into CLP mice. GFP+-C57BL/6 and C3H/HeN-C3H/HeJ parabiosis models were established. We found that HMGB1 pretreatment improved the survival of sepsis and increased the numbers of BMCs and liver immune cells in CLP mice. Furthermore, HMGB1 stimulation improved survival in the secondary pneumonia infection model. HMGB1 increased the number as well as the percentage of CD11c- CD45RBhigh DCs in septic BM and liver. Adoptive transfer of septic cells pretreated with HMGB1 into CLP mice attenuated sepsis. HMGB1 enhanced the redistribution of CD11c- CD45RBhigh DCs through TLR4 signaling in parabiosis models. We conclude that HMGB1 triggers immune reversal through the mobilization, redistribution, and local immune differentiation of BMCs, thereby compensating for impaired immunity and leading to sufficient bacterial eradication.

Polysaccharides from Bupleurum Induce Immune Reversal in Late Sepsis.

BACKGROUND: Bupleurum chinense, a well-known Traditional Chinese Medicine, has been used for thousands of years in China. In this study, we would suggest that Bupleurum polysaccharides (BPS) could improve the prognosis of sepsis through its impact on redistribution of BMCs, which triggers immune reversal in late sepsis. METHODS: BALB/c mice were divided into five groups: sham burn group, burn plus P aeruginosa group, burn plus P aeruginosa with BPS (40 mg/kg, 100 mg/kg, and 250 mg/kg) treatment group, and they were sacrificed at post-burn day (PBD) 0, 3, 5, and 7. BMCs, liver cells, and dendritic cells (DCs) were harvested. Flow cytometry was used to determine the change of phenotypes of DCs and isolate these cells. Cytometric beads array was utilized to analyze the level of inflammatory factors. Cell therapy of BMCs, liver cells, and DCs was administrated to explore the protective role of regional organ immunity. RESULTS: BPS could decrease the lethality of burn sepsis in a dose-dependent fashion and increase both the percentage of CD11cCD45RB DCs in bone marrow (BM) and liver and the number of BMCs and liver cells significantly. Cell therapy of BMCs, liver cells, and CD11cCD45RB DCs at PBD7 could protect septic mice from sepsis. CONCLUSION: BPS has shown its potential in promoting the prognosis of post-burn sepsis through its effect on immune redistribution of BMCs, especially via differentiation of CD11cCD45RB DC cells in BM and nonimmune organs to induce immune reversal in late sepsis.