Utility of urinary presepsin in the diagnosis of pyelonephritis: a cross-sectional study.

BACKGROUND: Presepsin is produced during the phagocytosis of bacteria by granulocytes. Presepsin increases at the site of infection; however, the significance of urinary presepsin in pyelonephritis is unknown. This study aimed to evaluate whether measuring urinary presepsin can distinguish between pyelonephritis and nonpyelonephritis. METHODS: A cross-sectional study of patients with suspected pyelonephritis was conducted. Urinary presepsin at admission was compared between the pyelonephritis and nonpyelonephritis groups using the Mann-Whitney test. The predictive accuracy of urinary presepsin for diagnosing pyelonephritis was evaluated by the area under the receiver operating characteristics (ROC) analysis curve. RESULTS: A total of 35 eligible participants were included in the pyelonephritis group and 25 in the nonpyelonephritis group. The median urinary presepsin level was 2232.0 (interquartile range [IQR], 1029.0-3907.0) pg/mL in the pyelonephritis group and 1348.0 (IQR, 614.5-2304.8) pg/mL in the nonpyelonephritis group. Urinary presepsin concentrations were significantly higher in the pyelonephritis group than in the nonpyelonephritis group (P = 0.023). ROC analysis of urinary presepsin revealed a cutoff value of 3650 pg/mL to distinguish between the pyelonephritis and nonpyelonephritis groups. Sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio for the diagnosis of pyelonephritis were 0.40 (95% confidence interval [CI], 0.24-0.58), 0.96 (95% CI, 0.79-1.00), 0.93 (95% CI, 0.68-1.00), 0.52 (95% CI, 0.37-0.68), 9.60 (95% CI, 1.35-68.23), and 0.62 (95% CI, 0.47-0.83), respectively. CONCLUSIONS: The measurement of urinary presepsin is useful in differentiating pyelonephritis from other diseases.

Nonclassical Monocytes (CD14dimCD16+) Are Associated With Carotid Intima-Media Thickness Progression for Men but Not Women: The Multi-Ethnic Study of Atherosclerosis-Brief Report.

[Figure: see text].

Glucocorticoid treatment in patients with newly diagnosed immune thrombocytopenia switches CD14++ CD16+ intermediate monocytes from a pro-inflammatory to an anti-inflammatory phenotype.

Immune thrombocytopenia (ITP) is thought to result from an aberrant adaptive autoimmune response, involving autoantibodies, B and T lymphocytes, directed at platelets and megakaryocytes. Previous reports have demonstrated skewed CD4+ T-helper subset distribution and enhanced production of pro-inflammatory cytokines such as interleukin 17A and interferon gamma. The role of monocytes (MCs) in ITP is less widely described, but innate immune cells have a role in shaping CD4+ T-cell phenotypes. Glucocorticoids (GCs) are commonly used for first-line ITP treatment and modulate a broad range of immune cells including T cells and MCs. Using multiparameter flow cytometry analysis, we demonstrate the expansion of intermediate MCs (CD14++ CD16+ ) in untreated patients with newly diagnosed ITP, with these cells displaying a pro-inflammatory phenotype, characterised by enhanced expression of CD64 and CD80. After 2 weeks of prednisolone treatment (1 mg/kg daily), the proportion of intermediate MCs reduced, with enhanced expression of the anti-inflammatory markers CD206 and CD163. Healthy control MCs were distinctly different than MCs from patients with ITP before and after GC treatment. Furthermore, the GC-induced phenotype was not observed in patients with chronic ITP receiving thrombopoietin receptor agonists. These data suggest a role of MCs in ITP pathogenesis and clinical response to GC therapy.

Increased proportion and altered properties of intermediate monocytes in the peripheral blood of patients with lower risk Myelodysplastic Syndrome.

Immune deregulation has a critical role in the pathogenesis of lower risk myelodysplastic syndromes (MDS). The cells of the macrophage/monocyte lineage have been reported to contribute to the inflammatory process in MDS through impaired phagocytosis of the apoptotic hemopoietic cells and abnormal production of cytokines. In the present study we assessed the number of peripheral blood (PB) monocyte subsets, namely the classical CD14bright/CD16-, intermediate CD14bright/CD16+ and non-classical CD14dim/CD16+ cells, in patients with lower risk (low/intermediate-I) MDS (n = 32). We also assessed the production of tumor necrosis factor (TNF)α by patient PB monocytes in response to immune stimulus as well as their transcriptome profile. Compared to age- and sex-matched healthy individuals (n = 19), MDS patients had significantly lower number of classical and increased number of intermediate monocytes. Patient intermediate monocytes displayed increased production of TNFα following stimulation with lipopolysaccharide, compared to healthy individuals. Transcriptional profiling comparison of CD16+ monocytes from patients and controls revealed 43 differentially expressed genes mostly associated with biological pathways/processes relevant to hemopoiesis, immune signaling and cell adhesion. These data provide evidence for the first-time that distinct monocyte subsets display abnormal quantitative and functional characteristics in lower risk MDS substantiating their role in the immune deregulation associated with the disease.

Ethanol modulates the effector functions of human monocyte-derived macrophages in response to Paracoccidioides brasiliensis yeast cells.

We aimed to investigate the effects of ethanol and its metabolites (ß-hydroxybutyrate and sodium acetate) in the effector functions of macrophages in response to Paracoccidioides brasiliensis yeast cells and to determine their influence in the development of the adaptive response. Purified peripheral blood monocytes were differentiated into macrophages and were treated with ethanol, ß-hydroxybutyrate, and sodium acetate, and stimulated with P. brasiliensis yeast cells and evaluated for their phenotypic characteristics, functional activity, and capability to induce T cells activation/differentiation. We found that the ethanol treatment diminished the expression of HLA-AB, HLA-DR, CD80, and CD86, modulating the expression of dectin-1, as well as Syk phosphorylation. The ethanol treatment increased the phagocytic activity, expression of CD206, and IL-10 production; however, reduced ROS production, fungicidal activity, caspase-1 cleavage, and IL-1ß and IL-6 production. Our data also showed that the presence of ethanol reduced the differentiation of Th1 and Th17 cells and increased the frequency of Th2 cells. Our results indicated that ethanol exposure could suppress effector function of macrophages, possibly leading to the polarization of M2 macrophages. The ethanol modulates the expression of costimulatory and antigen-presentation molecules and interferes with the NLRP3 inflammasome. Altogether, these alterations affect the development of the adaptive response, decreasing the frequency of IL-17, IL-22, and IFN- γ producing cells, and increasing the frequency of IL-4 producing cells. Therefore, exposure to ethanol can impair the capability of macrophages to exert their effector functions and activate the acquired response related to resistance to P. brasiliensis infection.

Tracheal aspirate presepsin: a promising biomarker in early onset neonatal pneumonia.

The early recognition and management of early-onset neonatal pneumonia is a challenge facing intensivists. Presepsin is an emerging immunologic and inflammatory biomarker that has been used for early non-culture-based detection of infection. We aimed to clarify the potential of presepsin assessed in tracheal aspirate of newborns to identify pneumonia. This prospective case - control study was conducted on 60 intubated neonates: Thirty neonates with pneumonia diagnosed according to clinical, radiological, and laboratory criteria as pneumonia group and thirty age and sex-matched intubated neonates without pneumonia as a control group. All neonates underwent full clinical evaluation and laboratory investigations. Plasma and tracheal aspirate presepsin was determined on the first day of life. The means of tracheal aspirate and plasma presepsin and CRP (525.55 ± 94.62 pg/mL, 670.95 ± 120.38 pg/mL and 26.4 ± 11.2 mg/L, respectively) were significantly higher in pneumonia group than control group (252.51 ± 104.95 pg/mL, 553.79 ± 117.48 pg/mL, 15.1 ± 3.1 mg/L, respectively) (p < .001 each). Receiver operating characteristic curve analysis for tracheal aspirate and plasma presepsin and CRP levels for the prediction of early-onset neonatal pneumonia was designed. Sensitivity was 86.6, 70 and 56.7%, respectively, while specificity was 90, 73.3, 53.3%, respectively, at a cut-off point of 385 pg/mL, 605 pg/mL and 36 mg/L, respectively [area under the curve (AUC) = 0.97, 0.74 and 0.51, respectively, p < .001, .001 and .44, repectively]. In conclusion, tracheal aspirate presepsin is increased in early-onset neonatal pneumonia and outperformed other plasma biomarkers in diagnosing neonatal pneumonia.

Adipose tissue macrophage burden, systemic inflammation, and insulin resistance.

Adipose tissue inflammation, as defined by macrophage accumulation, is proposed to cause insulin resistance and systemic inflammation. Because the strength of this relationship for humans is unclear, we tested whether adipose tissue macrophage (ATM) burden is correlated with these health indicators. Using immunohistochemistry, we measured abdominal subcutaneous CD68+ (total ATM), CD14+ (proinflammatory/M1), and CD206+ (anti-inflammatory/M2) ATM in 97 volunteers (BMI 20-38 kg/m2, in addition to body composition, adipocyte size, homeostasis model assessment of insulin resistance, ADIPO-IR, adipose tissue insulin resistance measured by palmitate, plasma lipids, TNF, and IL-6 concentrations. There were several significant univariate correlations between metabolic parameters to IL-6 and ATM per 100 adipocytes, but not ATM per gram tissue; adipocyte size was a confounding variable. We used matching strategies and multivariate regression analyses to investigate the relationships between ATM and inflammatory/metabolic parameters independent of adipocyte size. Matching approaches revealed that the groups discordant for CD206 but concordant for adipocyte size had significantly different fasting insulin and IL-6 concentrations. However, groups discordant for adipocyte size but concordent for ATM differeded in that visceral fat, plasma triglyceride, glucose, and TNF concentrations were greater in those with large adipocytes. Multivariate regression analysis indicated that indexes of insulin resistance and fasting triglycerides were predicted by body composition; the predictive value of ATM per 100 adipocytes or per gram tissue was variable between males and females. We conclude that the relationship between ATM burden and metabolic/inflammatory variables is confounded by adipocyte size/body composition and that ATM do not predict insulin resistance, systemic inflammation, or dyslipidemia. ATM may primarily play a role in tissue remodeling rather than in metabolic pathology.

Epigenetic basis for monocyte dysfunction in patients with severe alcoholic hepatitis.

BACKGROUND & AIMS: Severe forms of alcohol-related liver disease are associated with increased susceptibility to infections which are associated with poor prognosis. The cellular and molecular mechanisms responsible for this altered host defense are incompletely understood. METHODS: We performed whole blood phenotypic analysis and ex vivo stimulation with various pathogen-associated molecular patterns (PAMPs). We included 34 patients with alcohol-related cirrhosis (18 of whom had biopsy-proven severe alcoholic hepatitis [sAH]), 12 healthy controls and 11 patients with chronic alcohol consumption without significant liver disease. We also evaluated the transcriptomic (RNA-seq) and chromatin accessibility (ATAC-seq) profiles of CD14+ monocytes from a subset of patients. RESULTS: Circulating monocytes and conventional dendritic cells (DCs) from patients with sAH displayed complex alterations characterized by increased expression of both activating and inhibitory surface markers and an impaired pro-inflammatory response upon stimulation with PAMPs representative of gram-negative bacteria (lipopolysaccharide, Pam3CSK4) or fungal pathogens (Zymosan). Their decreased ability to produce more than 1 cytokine (polyfunctionality) upon PAMP stimulation correlated with the risk of developing infection at 28 days or mortality at 90 days. The presence of acute-on-chronic liver failure in patients with sAH did not significantly modify the immune profile of monocytes and DCs. Moreover, CD14+ monocytes of patients with sAH displayed altered transcriptional and epigenomic profiles characterized by downregulation of key innate immune and metabolic pathways and upregulation of important immunomodulatory factors. CONCLUSIONS: In patients with sAH, the altered transcriptional program and functional properties of monocytes that contribute to patients' susceptibility to infection have strong epigenetic determinants. LAY SUMMARY: Patients with severe alcoholic hepatitis are at increased risk of infections, which contribute to the poor prognosis associated with the disease. Herein, we show that epigenetic determinants underly the immune cell dysfunction and inappropriate responses to pathogens that are associated with severe alcoholic hepatitis.

CD14+ CD16+ monocytes are involved in daratumumab-mediated myeloma cells killing and in anti-CD47 therapeutic strategy.

A deep elucidation of the mechanisms of action of anti-CD38 monoclonal antibodies (mAbs), such as daratumumab (DARA), is required to identify patients with multiple myeloma (MM) who are more responsive to this treatment. In the present study, an autologous ex vivo approach was established, focussing on the role of the monocytes in the anti CD38-mediated killing of MM cells. In bone marrow (BM) samples from 29 patients with MM, we found that the ratio between monocytes (CD14+ ) and MM cells (CD138+ ) influences the response to DARA. Further, the exposure of the BM samples to DARA is followed by the formation of a CD138+ CD14+ double-positive (DP) population, that quantitatively correlates with the anti-MM cells killing. These effects were dependent on the presence of a CD14+ CD16+ monocyte subset and on high CD16 expression levels. Lastly, the addition of a mAb neutralising the CD47/signal-regulatory protein α (SIRPα) axis was able to increase the killing mediated by DARA. The effects were observed only in coincidence with high CD14+ :CD138+ ratio, with a significant presence of the DP population and were correlated with CD16 expression. In conclusion, the present study underlines the critical role of the CD16+ monocytes in DARA anti-MM killing effects and gives a rationale to test the combination of an anti-CD47 mAb with anti-CD38 mAbs.

Antibody combinations for optimized staining of macrophages in human lung tumours.

The analysis of tumour-associated macrophages (TAMs) has a high potential to predict cancer recurrence and response to immunotherapy. However, the heterogeneity of TAMs poses a challenge for quantitative and qualitative measurements. Here, we critically evaluated by immunohistochemistry and flow cytometry two commonly used pan-macrophage markers (CD14 and CD68) as well as some suggested markers for tumour-promoting M2 macrophages (CD163, CD204, CD206 and CD209) in human non-small cell lung cancer (NSCLC). Tumour, non-cancerous lung tissue and blood were investigated. For immunohistochemistry, CD68 was confirmed to be a useful pan-macrophage marker although careful selection of antibody was found to be critical. The widely used anti-CD68 antibody clone KP-1 stains both macrophages and neutrophils, which is problematic for TAM quantification because lung tumours contain many neutrophils. For TAM counting in tumour sections, we recommend combined labelling of CD68 with a cell membrane marker such as CD14, CD163 or CD206. In flow cytometry, the commonly used combination of CD14 and HLA-DR was found to not be optimal because some TAMs do not express CD14. Instead, combined staining of CD68 and HLA-DR is preferable to gate all TAMs. Concerning macrophage phenotypic markers, the scavenger receptor CD163 was found to be expressed by a substantial fraction (50%-86%) of TAMs with a large patient-to-patient variation. Approximately 50% of TAMs were positive for CD206. Surprisingly, there was no clear overlap between CD163 and CD206 positivity, and three distinct TAM sub-populations were identified in NSCLC tumours: CD163+ CD206+ , CD163+ CD206- and CD163- CD206- . This work should help develop macrophage-based prognostic tools for cancer.

The alarmin S100A9 hampers osteoclast differentiation from human circulating precursors by reducing the expression of RANK.

The alarmin S100A8/A9 is implicated in sterile inflammation-induced bone resorption and has been shown to increase the bone-resorptive capacity of mature osteoclasts. Here, we investigated the effects of S100A9 on osteoclast differentiation from human CD14+ circulating precursors. Hereto, human CD14+ monocytes were isolated and differentiated toward osteoclasts with M-CSF and receptor activator of NF-κB (RANK) ligand (RANKL) in the presence or absence of S100A9. Tartrate-resistant acid phosphatase staining showed that exposure to S100A9 during monocyte-to-osteoclast differentiation strongly decreased the numbers of multinucleated osteoclasts. This was underlined by a decreased resorption of a hydroxyapatite-like coating. The thus differentiated cells showed a high mRNA and protein production of proinflammatory factors after 16 h of exposure. In contrast, at d 4, the cells showed a decreased production of the osteoclast-promoting protein TNF-α. Interestingly, S100A9 exposure during the first 16 h of culture only was sufficient to reduce osteoclastogenesis. Using fluorescently labeled RANKL, we showed that, within this time frame, S100A9 inhibited the M-CSF-mediated induction of RANK. Chromatin immunoprecipitation showed that this was associated with changes in various histone marks at the epigenetic level. This S100A9-induced reduction in RANK was in part recovered by blocking TNF-α but not IL-1. Together, our data show that S100A9 impedes monocyte-to-osteoclast differentiation, probably via a reduction in RANK expression.-Di Ceglie, I., Blom, A. B., Davar, R., Logie, C., Martens, J. H. A., Habibi, E., Böttcher, L.-M., Roth, J., Vogl, T., Goodyear, C. S., van der Kraan, P. M., van Lent, P. L., van den Bosch, M. H. The alarmin S100A9 hampers osteoclast differentiation from human circulating precursors by reducing the expression of RANK.

Human Monocyte Heterogeneity as Revealed by High-Dimensional Mass Cytometry.

Objective- Three distinct human monocyte subsets have been identified based on the surface marker expression of CD14 and CD16. We hypothesized that monocytes were likely more heterogeneous in composition. Approach and Results- We used the high dimensionality of mass cytometry together with the FlowSOM clustering algorithm to accurately identify and define monocyte subsets in blood of healthy human subjects and those with coronary artery disease (CAD). To study the behavior and functionality of the newly defined monocyte subsets, we performed RNA sequencing, transwell migration, and efferocytosis assays. Here, we identify 8 human monocyte subsets based on their surface marker phenotype. We found that 3 of these subsets fall within the CD16+ nonclassical monocyte population and 4 subsets belong to the CD14+ classical monocytes, illustrating significant monocyte heterogeneity in humans. As nonclassical monocytes are important in modulating atherosclerosis in mice, we studied the functions of our 3 newly identified nonclassical monocytes in subjects with CAD. We found a marked expansion of a Slan+CXCR6+ nonclassical monocyte subset in CAD subjects, which was positively correlated with CAD severity. This nonclassical subset can migrate towards CXCL16 and shows an increased efferocytosis capacity, indicating it may play an atheroprotective role. Conclusions- Our data demonstrate that human nonclassical monocytes are a heterogeneous population, existing of several subsets with functional differences. These subsets have changed frequencies in the setting of severe CAD. Understanding how these newly identified subsets modulate CAD will be important for CAD-based therapies that target myeloid cells.

An analysis of monocytes and dendritic cells differentiated from human peripheral blood monocyte-derived induced pluripotent stem cells.

Dendritic cell-based immunotherapy, which uses a patient's own immune cells, can be used for cancer treatment and allergy control, such as autoimmune disease and rejection associated with transplantation. However, these treatments create a burden on patients due to repeated blood collection. We used cell biological analysis of monocytes with few mutations obtained from minimal blood collection for genome recombination. Next, we established human peripheral blood monocyte-derived induced pluripotent stem cells (iPSCs) using a commercial vector and standard culture method. We found that when established iPSCs were induced to differentiate, monocytes showed phagocytic properties and expressed CD14 and CX3CR1. Further, the generated dendritic cells (DCs) expressed CCL17 and highly expressed HLA-DR following the addition of the mite antigen. Taken together, these data show that monocyte-derived iPS cells can be used to differentiate into monocytes and DCs. In addition, the use of these cells can be applied to the pathological analysis of dendritic cell therapy and monocyte diseases.

Accessible Telemedicine Diagnostics with ELISA in a 3D Printed Pipette Tip.

We report herein a novel pipet-based "ELISA in a tip" as a new versatile diagnostic tool featuring better sensitivity, shorter incubation time, accessibility, and low sample and reagent volumes compared to traditional ELISA. Capture and analysis of data by a cell phone facilitates electronic delivery of results to health care providers. Pipette tips were designed and 3D printed as adapters to fit most commercial 50-200 µL pipettes. Capture antibodies (Ab1) are immobilized on the inner walls of the pipet tip, which serves as the assay compartment where samples and reagents are moved in and out by pipetting. Signals are generated using colorimetric or chemiluminescent (CL) reagents and can be quantified using a cell phone, CCD camera, or plate reader. We utilized pipet-tip ELISA to detect four cancer biomarker proteins with detection limits similar to or lower than microplate ELISAs at 25% assay cost and time. Recoveries of these proteins from spiked human serum were 85-115% or better, depending slightly on detection mode. Using CCD camera quantification of CL with femto-luminol reagent gave limits of detection (LOD) as low as 0.5 pg/mL. Patient samples (13) were assayed for 3 biomarker proteins with results well correlated to conventional ELISA and an established microfluidic electrochemical immunoassay.

Alterations in bacterial communities, SCFA and biomarkers in an elderly HIV-positive and HIV-negative population in western Mexico.

BACKGROUND: The study of stool microbiota has taken great relevance in the last years, given its role in the maintenance of the intestinal metabolic, physiological, and immunological homeostasis, as well as, its effect over HIV biomarkers levels such as CD4/CD8 ratio, high sensitivity C-Reactive Protein (hs-CRP), related to poor outcomes (rapid progression to AIDS). Several efforts have been made to characterize the gut microbiome. In HIV infection, most of the studies report the presence of a dysbiotic pattern; however, few of them have made an approach in elderly HIV-positive subjects despite the fact that nowadays this subgroup is rising. In this study, we compared the composition of faecal microbiota, Short Chain Fatty Acids (SCFAs), and systemic biomarkers between elderly HIV-positive and HIV-negative subjects. METHODS: A cross-sectional study with 18 HIV-negative controls and 20 HIV-positive patients. The quantification of Bacteroidetes, Firmicutes, Proteobacteria, Actinobacteria, Lactobacillus, Enterobacteriaceae, Bifidobacterium, Escherichia coli, Clostridium leptum, Clostridium coccoides was performed in faecal samples by qPCR. The analysis was performed by calculating the ΔCq of each microorganism using 16S rDNA as a reference gene. Faecal SCFAs were measured by HPLC. The hs-CRP and sCD14 were performed by ELISA. RESULTS: An increase in the Firmicutes/Bacteroidetes ratio, coupled with a significant increase in the proteobacteria phylum was detected in HIV-positive subjects. In contrast, a decrease in the Clostridium leptum group was observed. Nevertheless, these elderly HIV-positive patients showed higher levels of total SCFAs mainly by an augmented propionic acid values, compared to HIV-negative subjects. Whereas high levels of hs-CRP were positively correlated with sCD14 in the HIV-positive group. CONCLUSIONS: Alterations in bacterial communities reveals a dysbiotic state related to an unbalance of faecal SCFAs. Therefore, these intestinal conditions might drive an increase of poor prognostic biomarkers in elderly HIV-positive subjects.

Presepsin as a diagnostic marker of sepsis in children and adolescents: a systemic review and meta-analysis.

BACKGROUND: Early diagnosis of sepsis in pediatric patients is vital but remains a major challenge. Previous studies showed that presepsin is potentially a reliable diagnostic biomarker for sepsis in adult and neonates. However, there is no pooled analysis of its efficacy as a diagnostic biomarker for sepsis in children. The aims of the present meta-analysis were to assess the overall diagnostic accuracy of presepsin in pediatric sepsis and compare it to those for C-reactive protein (CRP) and procalcitonin (PCT). METHODS: A systematic literature search was performed in Medline/Pubmed, Embase, the Cochrane Library, and ISI Web of Science to identify relevant studies reporting the diagnostic accuracy of presepsin in patients with pediatric sepsis. Sensitivities and specificities were pooled by bivariate meta-analysis. Heterogeneity was evaluated by χ2 test. RESULTS: We identified 129 studies in total. Most were disqualified on the basis of their titles/abstracts and duplication. Four studies were included in the final analysis. They comprised 308 patients aged between 1 mo and 18 y. The pooled diagnostic sensitivity and specificity of presepsin were 0.94 (95% confidence interval [CI]: 0.74-0.99) and 0.71 (95% CI: 0.35-0.92), respectively. The pooled diagnostic odds ratio, positive likelihood ratio (LR), and negative LR of presepsin were 32.87 (95% CI: 2.12-510.09), 3.24 (95% CI, 1.14-12.38), and 0.08 (95% CI, 0.01-0.74), respectively. Heterogeneity was found in both sensitivity (χ2 = 11.17; P = 0.011) and specificity (χ2 = 65.78; P < 0.001). No threshold effect was identified among the studies (r = - 0.938). The pooled sensitivity of presepsin (0.94) was higher than that of CRP (0.51) and PCT (0.76), whereas the overall specificity of presepsin (0.71) was lower than that of CRP (0.81) and PCT (0.76). The AUC of presepsin (0.925) was higher than that of CRP (0.715) and PCT (0.820). CONCLUSION: Currently available evidence indicates that presepsin has higher sensitivity and diagnostic accuracy, but lower specificity, than PCT or CRP in detecting sepsis in children. However, these results must be carefully interpreted as the number of studies included was small and the studies were statistically heterogeneous.

Immune Modifications in Fetal Membranes Overlying the Cervix Precede Parturition in Humans.

In humans, parturition is currently viewed as an intrauterine outbreak of inflammation, accompanied by a massive release of proinflammatory cytokines at the maternal-fetal interface that comprises the maternal decidua, placenta, and fetal membranes. At term, fetal membranes overlying the cervix, the future site of rupture, show altered morphology and are termed the zone of altered morphology (ZAM). These alterations occur in normal fetal membranes during late pregnancy, in preparation for labor. In this study, transcriptome, flow cytometry, electron microscopy, and immunohistochemistry analyses collectively highlight a local shift in gene expression and lymphocyte activation in the ZAM. Just before labor, we show that highly polymorphic HLA-A, -B, and -C determinants of fetal origin are selectively exposed in the ZAM to the maternal immune system. A graft rejection-like program occurs in the ZAM, which involves 1) the activation of cytotoxic decidual NK cells, and 2) the decline of decidual immunotolerant M2-like macrophages. Comparison with a prior cohort of fetal membranes shows that acute inflammation only takes place after these first steps of immune modifications. Our results therefore strongly argue in favor of local immune remodeling at the onset of parturition.

Transcriptional Classification and Functional Characterization of Human Airway Macrophage and Dendritic Cell Subsets.

The respiratory system is a complex network of many cell types, including subsets of macrophages and dendritic cells that work together to maintain steady-state respiration. Owing to limitations in acquiring cells from healthy human lung, these subsets remain poorly characterized transcriptionally and phenotypically. We set out to systematically identify these subsets in human airways by developing a schema of isolating large numbers of cells by whole-lung bronchoalveolar lavage. Six subsets of phagocytic APC (HLA-DR+) were consistently observed. Aside from alveolar macrophages, subsets of Langerin+, BDCA1-CD14+, BDCA1+CD14+, BDCA1+CD14-, and BDCA1-CD14- cells were identified. These subsets varied in their ability to internalize Escherichia coli, Staphylococcus aureus, and Bacillus anthracis particles. All subsets were more efficient at internalizing S. aureus and B. anthracis compared with E. coli Alveolar macrophages and CD14+ cells were overall more efficient at particle internalization compared with the four other populations. Subsets were further separated into two groups based on their inherent capacities to upregulate surface CD83, CD86, and CCR7 expression levels. Whole-genome transcriptional profiling revealed a clade of "true dendritic cells" consisting of Langerin+, BDCA1+CD14+, and BDCA1+CD14- cells. The dendritic cell clade was distinct from a macrophage/monocyte clade, as supported by higher mRNA expression levels of several dendritic cell-associated genes, including CD1, FLT3, CX3CR1, and CCR6 Each clade, and each member of both clades, was discerned by specific upregulated genes, which can serve as markers for future studies in healthy and diseased states.

Human Monocyte Subsets Are Transcriptionally and Functionally Altered in Aging in Response to Pattern Recognition Receptor Agonists.

Age-related alterations in immunity have been linked to increased incidence of infections and decreased responses to vaccines in the aging population. Human peripheral blood monocytes are known to promote Ag presentation and antiviral activities; however, the impact of aging on monocyte functions remains an open question. We present an in-depth global analysis examining the impact of aging on classical (CD14+CD16-), intermediate (CD14+CD16+), and nonclassical (CD14dimCD16+) monocytes. Monocytes sorted from nonfrail healthy adults (21-40 y) and old (≥65 y) individuals were analyzed after stimulation with TLR4, TLR7/8, and retinoic acid-inducible gene I agonists. Our data showed that under nonstimulated conditions, monocyte subsets did not reveal significant age-related alternations; however, agonist stimulated-monocytes from adults and old subjects did show differences at the transcriptional and functional levels. These alternations in many immune-related transcripts and biological processes resulted in reduced production of IFN-α, IFN-γ, IL-1ß, CCL20, and CCL8, and higher expression of CX3CR1 in monocytes from old subjects. Our findings represent a comprehensive analysis of the influence of human aging on pattern recognition receptors signaling and monocyte functions, and have implications for strategies to enhance the immune response in the context of infection and immunization.

Flow Cytometry Characterization of Cerebrospinal Fluid Monocytes in Patients With Postoperative Cognitive Dysfunction: A Pilot Study.

Animal models suggest postoperative cognitive dysfunction may be caused by brain monocyte influx. To study this in humans, we developed a flow cytometry panel to profile cerebrospinal fluid (CSF) samples collected before and after major noncardiac surgery in 5 patients ≥60 years of age who developed postoperative cognitive dysfunction and 5 matched controls who did not. We detected 12,654 ± 4895 cells/10 mL of CSF sample (mean ± SD). Patients who developed postoperative cognitive dysfunction showed an increased CSF monocyte/lymphocyte ratio and monocyte chemoattractant protein 1 receptor downregulation on CSF monocytes 24 hours after surgery. These pilot data demonstrate that CSF flow cytometry can be used to study mechanisms of postoperative neurocognitive dysfunction.