Abstract
Background
From December 2019 to February 2020, 2019 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a serious outbreak of coronavirus disease 2019 (COVID-19) in ...Wuhan, China. Related clinical features are needed.
Methods
We reviewed 69 patients who were hospitalized in Union hospital in Wuhan between 16 January and 29 January 2020. All patients were confirmed to be infected with SARS-CoV-2, and the final date of follow-up was 4 February 2020.
Results
The median age of 69 enrolled patients was 42.0 years (interquartile range 35.0–62.0), and 32 patients (46%) were men. The most common symptoms were fever (60 87%), cough (38 55%), and fatigue (29 42%). Most patients received antiviral therapy (66 98.5% of 67 patients) and antibiotic therapy (66 98.5% of 67 patients). As of 4 February 2020, 18 (26.9%) of 67 patients had been discharged, and 5 patients had died, with a mortality rate of 7.5%. According to the lowest SpO2 during admission, cases were divided into the SpO2 ≥ 90% group (n = 55) and the SpO2 < 90% group (n = 14). All 5 deaths occurred in the SpO2 < 90% group. Compared with SpO2 ≥ 90% group, patients of the SpO2 < 90% group were older and showed more comorbidities and higher plasma levels of interleukin (IL) 6, IL10, lactate dehydrogenase, and C reactive protein. Arbidol treatment showed tendency to improve the discharging rate and decrease the mortality rate.
Conclusions
COVID-19 appears to show frequent fever, dry cough, and increase of inflammatory cytokines, and induced a mortality rate of 7.5%. Older patients or those with underlying comorbidities are at higher risk of death.
In this retrospective case series that included 69 adults in Wuhan, 29% of patients showed dyspnea and 20% of cases showed SpO2 < 90%. Patients with SpO2 < 90% had a significantly higher risk of death. Abidol showed initial therapeutic effect.
Interleukin-10 (IL-10) is a critical cytokine used by immune cells to suppress inflammation. Paradoxically, immune cell-derived IL-10 can drive insulin resistance in obesity by suppressing adipocyte ...energy expenditure and thermogenesis. However, the source of IL-10 necessary for the suppression of adipocyte thermogenesis is unknown. We show here that CD4+Foxp3+ regulatory T cells (Tregs) are a substantial source of IL-10 and that Treg-derived IL-10 can suppress adipocyte beiging. Unexpectedly, Treg-specific loss of IL-10 resulted in increased insulin sensitivity and reduced obesity in high-fat diet-fed male mice. Mechanistically, we determined that Treg-specific loss of the transcription factor Blimp-1, a driver of IL-10 expression by Tregs, phenocopied the Treg-specific IL-10-deficient mice. Loss of Blimp-1 expression in Tregs resulted in reduced ST2+KLRG1+, IL-10-secreting Tregs, particularly in the white adipose tissue. Blimp-1-deficient mice were protected from glucose intolerance, insulin resistance, and diet-induced obesity, through increased white adipose tissue browning. Taken together, our data show that Blimp-1-regulated IL-10 secretion by Tregs represses white adipose tissue beiging to maintain adipose tissue homeostasis.
Acute lung injury (ALI) initiates protective responses involving genes downstream of the Nrf2 (Nfe2l2) transcription factor, including heme oxygenase-1 (HO-1), which stimulates mitochondrial ...biogenesis and related anti-inflammatory processes. We examined mitochondrial biogenesis during Staphylococcus aureus pneumonia in mice and the effect of Nrf2 deficiency on lung mitochondrial biogenesis and resolution of lung inflammation. S. aureus pneumonia established by nasal insufflation of live bacteria was studied in mitochondrial reporter (mt-COX8-GFP) mice, wild-type (WT) mice, and Nrf2−/− mice. Bronchoalveolar lavage, wet/dry ratios, real-time RT-PCR and Western analysis, immunohistochemistry, and fluorescence microscopy were performed on the lung at 0, 6, 24, and 48h. The mice survived S. aureus inoculations at 5×108 CFU despite diffuse lung inflammation and edema, but the Nrf2−/− lung showed increased ALI. In mt-COX8-GFP mice, mitochondrial fluorescence was enhanced in bronchial and alveolar type II (AT2) epithelial cells. WT mice displayed rapid HO-1 upregulation and lower proinflammatory TNF-α, IL-1β, and CCL2 and, especially in AT2 cells, higher anti-inflammatory IL-10 and suppressor of cytokine signaling-3 than Nrf2−/− mice. In the alveolar region, WT but not Nrf2−/− mice showed strongly induced nuclear respiratory factor-1, PGC-1α, mitochondrial transcription factor-A, SOD2, Bnip3, mtDNA copy number, and citrate synthase. These findings indicate that S. aureus pneumonia induces Nrf2-dependent mitochondrial biogenesis in the alveolar region, mainly in AT2 cells. Absence of Nrf2 suppresses the alveolar transcriptional network for mitochondrial biogenesis and anti-inflammation, which worsens ALI. The findings link redox activation of mitochondrial biogenesis to ALI resolution.
► Staphylococcus aureus pneumonia induces alveolar mitochondrial biogenesis in mice. Nrf2−/− mice show impaired lung mitochondrial biogenesis compared to WT mice. ► Type II cells are a main site of Nrf2-regulated alveolar mitochondrial biogenesis. ► Nrf2−/− mice have low type II cell anti-inflammatory IL-10 and SOCS3 responses. ► Nrf2 links alveolar mitochondrial biogenesis to local IL-10 and SOCS3 synthesis.
Lung epithelial cells can influence immune responses to airway allergens. Airway epithelial cells also undergo apoptosis after encountering environmental allergens; yet, relatively little is known ...about how these are cleared, and their effect on airway inflammation. Here we show that airway epithelial cells efficiently engulf apoptotic epithelial cells and secrete anti-inflammatory cytokines, dependent upon intracellular signalling by the small GTPase Rac1. Inducible deletion of Rac1 expression specifically in airway epithelial cells in a mouse model resulted in defective engulfment by epithelial cells and aberrant anti-inflammatory cytokine production. Intranasal priming and challenge of these mice with house dust mite extract or ovalbumin as allergens led to exacerbated inflammation, augmented Th2 cytokines and airway hyper-responsiveness, with decreased interleukin (IL)-10 in bronchial lavages. Rac1-deficient epithelial cells produced much higher IL-33 upon allergen or apoptotic cell encounter, with increased numbers of nuocyte-like cells. Administration of exogenous IL-10 'rescued' the airway inflammation phenotype in Rac1-deficient mice, with decreased IL-33. Collectively, these genetic and functional studies suggest a new role for Rac1-dependent engulfment by airway epithelial cells and in establishing the anti-inflammatory environment, and that defects in cell clearance in the airways could contribute to inflammatory responses towards common allergens.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
BACKGROUND CD4+CD25+ regulatory T cells (Tregs) are important for the maintenance of immune homeostasis by virtue of their ability to control T-cell proliferation in the peripheral blood (PB). We ...recently demonstrated that the prevalence of Tregs is decreased, whereas that of Th17 cells is increased, in the PB and decidua samples of patients with unexplained recurrent miscarriage (RM). In this study, we investigated whether the cytokine production of Th17 cells can be suppressed by the Tregs and elucidated the mechanism by which Tregs exert this suppressive effect. METHODS Flow cytometry was used to analyze the surface phenotype and cytokine production of Th17 cells in the PB of women with unexplained RM (n = 17) and healthy women in early stages of pregnancy who underwent elective abortion (n = 20). The suppressive ability of Tregs on Th17 cells was assessed in in vitro co-cultures and transwell experiments. The amount of secreted interleukin-17 (IL-17) in the supernatants was measured by enzyme-linked immunosorbent assay (ELISA). The inhibitory activity of transforming growth factor-β (TGF-β) and IL-10 on IL-17 expression in CD4+ T cells was assessed using ELISA. RESULTS The proportions of IL-17-positive CD4+ T cells, CC chemokine receptor type 6 (CCR6)-positive CD4+ T cells and CCR6 expression of IL-17-positive CD4+ T cells were higher in the PB samples of patients with unexplained RM than in PB of healthy control subjects. In vitro, Tregs could inhibit the expression of IL-17; more Th17 cells were inhibited in the control group than in the unexplained RM group. High-dose TGF-β inhibited the expression of IL-17, whereas IL-10 inhibited IL-17 expression in a dose-dependent manner. CONCLUSIONS IL-17 expression can be inhibited by Tregs. The suppressive activity of Tregs on Th17 cells was decreased in patients with unexplained RM. The ability of Tregs to suppress cytokine secretion might be effected by a cell–cell contact. TGF-β and IL-10 could inhibit the expression of IL-17.
Non-typhoidal Salmonella serotypes (NTS) cause a self-limited gastroenteritis in immunocompetent individuals, while children with severe Plasmodium falciparum malaria can develop a life-threatening ...disseminated infection. This co-infection is a major source of child mortality in sub-Saharan Africa. However, the mechanisms by which malaria contributes to increased risk of NTS bacteremia are incompletely understood. Here, we report that in a mouse co-infection model, malaria parasite infection blunts inflammatory responses to NTS, leading to decreased inflammatory pathology and increased systemic bacterial colonization. Blunting of NTS-induced inflammatory responses required induction of IL-10 by the parasites. In the absence of malaria parasite infection, administration of recombinant IL-10 together with induction of anemia had an additive effect on systemic bacterial colonization. Mice that were conditionally deficient for either myeloid cell IL-10 production or myeloid cell expression of IL-10 receptor were better able to control systemic Salmonella infection, suggesting that phagocytic cells are both producers and targets of malaria parasite-induced IL-10. Thus, IL-10 produced during the immune response to malaria increases susceptibility to disseminated NTS infection by suppressing the ability of myeloid cells, most likely macrophages, to control bacterial infection.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Antiparasite responses are associated with the recruitment of monocytes that differentiate to macrophages and dendritic cells at the site of infection. Although classically activated monocytic cells ...are assumed to be the major source of TNF and NO during Trypanosoma brucei brucei infection, their cellular origin remains unclear. In this study, we show that bone marrow-derived monocytes accumulate and differentiate to TNF/inducible NO synthase-producing dendritic cells (TIP-DCs) in the spleen, liver, and lymph nodes of T. brucei brucei-infected mice. Although TIP-DCs have been shown to play a beneficial role in the elimination of several intracellular pathogens, we report that TIP-DCs, as a major source of TNF and NO in inflamed organs, could contribute actively to tissue damage during the chronic stage of T. brucei brucei infection. In addition, the absence of IL-10 leads to enhanced differentiation of monocytes to TIP-DCs, resulting in exacerbated pathogenicity and early death of the host. Finally, we demonstrate that sustained production of IL-10 following IL-10 gene delivery treatment with an adeno-associated viral vector to chronically infected mice limits the differentiation of monocytes to TIP-DCs and protects the host from tissue damage.
Abstract Implanted synthetic substrates for the regeneration of cardiovascular tissues are exposed to mechanical forces that induce local deformation. Circulating inflammatory cells, actively ...participating in the healing process, will be subjected to strain once recruited. We investigated the effect of deformation on human peripheral blood mononuclear cells (hPBMCs) adherent onto a scaffold, with respect to macrophage polarization towards an inflammatory (M1) and reparative (M2) phenotype and to early tissue formation. HPBMCs were seeded onto poly-ε-caprolactone bisurea strips and subjected to 0%, 7% and 12% cyclic strain for up to one week. After 1 day, cells subjected to 7% deformation showed upregulated expression of pro and anti-inflammatory chemokines, such as MCP-1 and IL10. Immunostaining revealed presence of inflammatory macrophages in all groups, while immunoregulatory macrophages were detected mainly in the 0 and 7% groups and increased significantly over time. Biochemical assays indicated deposition of sulphated glycosaminoglycans and collagen after 7 days in both strained and unstrained samples. These results suggest that 7% cyclic strain applied to hPBMCs adherent on a scaffold modulates their polarization towards reparative macrophages and allows for early synthesis of extracellular matrix components, required to promote further cell adhesion and proliferation and to bind immunoregulatory cytokines.
Macrophages respond to LPS by the rapid activation of proinflammatory cytokines that serve to initiate host defense against microbial invasion. To prevent injury to the host from excess production of ...these cytokines, IL-10 is up-regulated to feedback inhibit the proinflammatory response. However, the molecular events responsible for LPS-induced up-regulation of IL-10 remain to be elucidated. In this study, we provide evidence that production of and signaling by type I IFN is required for LPS-induced IL-10 up-regulation. In addition, we demonstrate that defect in type I IFN production and signaling results in a trend toward LPS-mediated superinduction of proinflammatory genes and cytokines in bone marrow-derived macrophages. Our findings suggest a novel anti-inflammatory role for the type I IFN production and signaling pathway in regulating LPS response in bone marrow-derived macrophages.
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