Plasma Levels Of sCD14 Research Articles

Interleukin-7 signalling defects in naive CD4+ T cells of HIV patients with CD4+ T-cell deficiency on antiretroviral therapy are associated with T-cell activation and senescence

To examine the relationship of defects in interleukin (IL)-7-induced naive CD4 T-cell homeostasis with residual immune activation and CD4 T-cell senescence in HIV patients receiving antiretroviral therapy (ART) who exhibit persistent CD4 T-cell deficiency. IL-7 induced proliferation of, and IL-7 receptor signalling in, total and naive CD4 T cells of HIV patients who had low (<350 cells/μl) or normal (>500 cells/μl) CD4 T-cell counts on ART was examined and related to markers of CD4 T-cell activation and senescence and innate immune activation. Total, naive (CD45RA CD27) and CD31 naive CD4 T cells from aviremic HIV patients (n=39) with nadir CD4 T-cell counts less than 100 cells/μl, who had received ART for a median time of 7 (range 1-11) years, were assessed for CD127 expression, proliferation (Ki67), signal transducer and activator of transcription 5 phosphorylation (pSTAT5) and CD127 modulation following IL-7 stimulation. Changes were related to proportions of CD4 T cells expressing HLA-DR or CD57 and plasma levels of sCD14, CXCL9 and CXCL10. Patients with CD4 T-cell deficiency exhibited lower expression of CD127 on total, naive and CD31 naive CD4 T cells. Downregulation of CD127 after culture with IL-7 correlated inversely with CD4 T-cell counts and directly with Ki67 expression. Induction of pSTAT5 in CD4 T-cell subsets was greater in patients with normal CD4 T-cell counts. CD127 expression correlated inversely with proportions of CD4CD57 T cells, and pSTAT5 induction correlated inversely with CD4 T-cell expression of HLA-DR and CD57. Defects of IL-7 signalling in HIV patients with persistent CD4 T-cell deficiency receiving ART are associated with CD4 T-cell activation and senescence.

Abstract P342: Macrophage Markers are Associated with Atherosclerotic Plaque and Distensibility in the Women’s Interagency HIV Study

Background: Atherosclerosis is characterized by infiltration of monocytes into the arterial wall, where they form atherosclerotic plaque. The inflammation pathways leading to cardiovascular disease through atherosclerosis may involve monocyte and macrophage activity in response to viral infection, including HIV and hepatitis C virus (HCV). We examined the association of three plasma markers of monocyte and macrophage activity, galectin-3 binding protein (Gal-3BP), soluble CD163 (sCD163), and soluble CD14 (sCD14), with subclinical atherosclerosis, in a subset of women participating in the Women’s Interagency HIV Study (WIHS). We hypothesized that higher levels are associated with greater disease. Methods: The WIHS is a longitudinal study of HIV-infected and -uninfected women from 6 U.S. sites. We analyzed 4 groups of 66 women each: HIV+/HCV+, HIV+/HCV-, HIV-/HCV+, and HIV-/HCV-, matched by age, race/ethnicity, and smoking status. Carotid artery B-mode ultrasound assessed two measures of subclinical atherosclerosis: distensibility (in 10 -6 *m 2 /N) and presence of atherosclerotic plaque (IMT &gt;1.5 mm). We created an inflammatory macrophage score (sum of the presence of plasma levels above the median for each marker, range 0-3) and assessed its independent cross-sectional association with subclinical CAD, using regression models with generalized estimating equations to take into account the matched design and controlling for known risk factors. We also assessed associations of Gal-3BP, sCD163, and sCD14 plasma levels individually with subclinical atherosclerosis. Results: 264 women were included (median age 46 [IQR 41-50], 62% black, 26% Hispanic, median distensibility 15.22 [IQR 11.05-21.76]). In models accounting for age, race/ethnicity, smoking, BMI, and CRP, higher macrophage scores were significantly associated with both a 1.5-fold greater odds of plaque (per elevated marker, 95% CI 1.06 to 2.09) and lower distensibility (β -1.40 units per marker, 95% CI -2.62 to -0.17). Gal-3BP alone was associated with both outcomes in adjusted analyses (OR plaque 1.51 per SD of Gal-3BP, 95% CI 1.01 to 2.26; β distensibility -1.48 units per SD, 95% CI -2.37 to -0.58). sCD163 was associated with a greater odds of plaque only (OR 1.90 per SD, 95% CI 1.16 to 3.12), while sCD14 was associated with lower distensibility (β -1.09 units per SD, 95% CI -2.14 to -0.03). When we stratified by HIV and HCV status, Gal-3BP levels were higher among HCV+ women than HCV- women (mean 12.4 vs. 8.6 μg/mL, p&lt;0.01), but did not differ by HIV status (mean 10.3 vs. 10.7 μg/mL, p=0.34). HIV+/HCV+ women had the highest levels of sCD163 and sCD14. Conclusions: Our data show that the macrophage inflammatory markers Gal-3BP, sCD163 and sCD14 are associated with subclinical carotid atherosclerosis in the setting of HIV and HCV infection. HCV infection may be more strongly associated with these markers than HIV infection.

Plasma sCD14 as a Biomarker to Predict Pulmonary Exacerbations in Cystic Fibrosis

BackgroundOne in four cystic fibrosis (CF) patients diagnosed with a pulmonary exacerbation will not recover their baseline lung function despite standard treatment. This highlights the importance of preventing such events. Clinical decision-making can be improved through a simple blood test that predicts individuals at elevated short-term risk of an exacerbation.MethodsWe obtained plasma samples from 30 stable CF patients from the St. Paul’s Hospital Adult CF Clinic (Vancouver, Canada). For 15 patients, an additional plasma sample was obtained during an exacerbation. Soluble CD14 (sCD14) and C-reactive protein (CRP) were quantified using ELISA kits. Myeloperoxidase (MPO), interleukin(IL)-6, IL-1β, monocyte chemoattractant protein-1 (MCP-1), vascular endothelial growth factor (VEGF), and granulocyte colony-stimulating factor (G-CSF) were quantified using Luminex™ immunoassays. Stable state biomarker levels were examined in their ability to predict individuals that would experience a pulmonary exacerbation requiring intravenous (IV) antibiotics within 4 months. Paired stable and exacerbation plasma biomarker levels were also compared.ResultssCD14 levels were significantly higher in patients that experienced a pulmonary exacerbation requiring IV antibiotics within 4 months (p = 0.001). sCD14 cut-off value of 1450 ng/mL was associated with an area under the curve of 0.91 (95% CI 0.83–0.99) for predicting an exacerbation within 4 months of a stable visit, with a sensitivity of 100% and specificity of 82%. Plasma sCD14 levels were significantly higher during exacerbations than during periods of clinical stability (p = 0.03).ConclusionsPlasma sCD14 is a promising biomarker for identifying CF patients who will exacerbate within 4 months of a stable visit but requires further study in larger, independent cohorts.

Decreases in colonic and systemic inflammation in chronic HIV infection after IL-7 administration.

Despite antiretroviral therapy (ART), some HIV-infected persons maintain lower than normal CD4+ T-cell counts in peripheral blood and in the gut mucosa. This incomplete immune restoration is associated with higher levels of immune activation manifested by high systemic levels of biomarkers, including sCD14 and D-dimer, that are independent predictors of morbidity and mortality in HIV infection. In this 12-week, single-arm, open-label study, we tested the efficacy of IL-7 adjunctive therapy on T-cell reconstitution in peripheral blood and gut mucosa in 23 ART suppressed HIV-infected patients with incomplete CD4+ T-cell recovery, using one cycle (consisting of three subcutaneous injections) of recombinant human IL-7 (r-hIL-7) at 20 µg/kg. IL-7 administration led to increases of both CD4+ and CD8+ T-cells in peripheral blood, and importantly an expansion of T-cells expressing the gut homing integrin α4β7. Participants who underwent rectosigmoid biopsies at study baseline and after treatment had T-cell increases in the gut mucosa measured by both flow cytometry and immunohistochemistry. IL-7 therapy also resulted in apparent improvement in gut barrier integrity as measured by decreased neutrophil infiltration in the rectosigmoid lamina propria 12 weeks after IL-7 administration. This was also accompanied by decreased TNF and increased FOXP3 expression in the lamina propria. Plasma levels of sCD14 and D-dimer, indicative of systemic inflammation, decreased after r-hIL-7. Increases of colonic mucosal T-cells correlated strongly with the decreased systemic levels of sCD14, the LPS coreceptor - a marker of monocyte activation. Furthermore, the proportion of inflammatory monocytes expressing CCR2 was decreased, as was the basal IL-1β production of peripheral blood monocytes. These data suggest that administration of r-hIL-7 improves the gut mucosal abnormalities of chronic HIV infection and attenuates the systemic inflammatory and coagulation abnormalities that have been linked to it.

Neuroprotective maraviroc monotherapy in simian immunodeficiency virus-infected macaques: reduced replicating and latent SIV in the brain.

Objective:HIV-associated neurocognitive deficits remain a challenge despite suppressive combined antiretroviral therapy. Given the association between HIV-induced central nervous system (CNS) disease and replication of HIV in immune-activated macrophages, CCR5 antagonists may attenuate CNS disease by modulating inflammatory signaling and by limiting viral replication.Design:To establish whether initiating CCR5 inhibition during early infection altered CNS disease progression, outcomes were compared between simian immunodeficiency virus (SIV)-infected macaques treated with maraviroc (MVC) versus untreated SIV-infected macaques.Methods:Six SIV-infected rhesus macaques were treated with MVC monotherapy for 5 months beginning 24 days postinoculation; 22 SIV-infected animals served as untreated controls. SIV RNA levels in plasma, cerobrospinal fluid, and brain, and CNS expression of TNFα and CCL2 were measured by qRT-PCR. Immunostaining for CD68 and amyloid precursor protein in the brain was measured by image analysis. Plasma sCD163 was measured by ELISA.Results:SIV RNA and proviral DNA levels in brain were markedly lower with MVC treatment, demonstrating CCR5 inhibition reduces CNS replication of SIV and may reduce the CNS latent viral reservoir. MVC treatment also lowered monocyte and macrophage activation, represented by CNS CD68 immunostaining and plasma sCD163 levels, and reduced both TNFα and CCL2 RNA expression in brain. Treatment also reduced axonal amyloid precursor protein immunostaining to levels present in uninfected animals, consistent with neuroprotection.Conclusion:CCR5 inhibitors may prevent neurologic disorders in HIV-infected individuals by reducing inflammation and by limiting viral replication in the brain. Furthermore, CCR5 inhibitors may reduce the latent viral reservoir in the CNS. Adding CCR5 inhibitors to combined antiretroviral regimens may offer multiple neuroprotective benefits.

Elevated sCD163 in plasma but not cerebrospinal fluid is a marker of neurocognitive impairment in HIV infection

Here we evaluated whether neurocognitive disorders in HIV-infected individuals on effective antiretroviral therapy (ART) are associated with persistent monocyte activation as indexed by levels of soluble CD163 (sCD163), shed by monocyte/macrophages. Chronically, HIV-infected individuals were examined at two consecutive visits median [interquartile range (IQR)] 16 (7-32) months apart. All patients were on ART and durably virologically suppressed (plasma HIV RNA <50 copies/ml) at all visits. Thirty-four age-matched HIV-seronegative patients were used as controls. A global deficit score (GDS) was calculated based on comprehensive neuropsychological assessment according to standard methods. Neuropsychological and medical data were used to assign neurocognitive status according to published guidelines for HIV-associated neurocognitive disorders (HAND) as follows: neuropsychologically normal (NP-nml), asymptomatic neuropsychological impairment (ANI) and minor neurocognitive disorder (MND). sCD163 in plasma and cerebrospinal fluid was measured using ELISA. GDS-impaired patients had higher plasma sCD163 than those who were not impaired [median (IQR) 1401 ng/ml (1057-2258) versus 955 ng/ml (586-1313); Wilcoxon P=0.028]. Patients with MND (N=6) had significantly higher plasma sCD163 than ANI (P=0.04) or NP-nml (P=0.02). Whereas plasma sCD163 levels dropped in patients who were stably GDS-unimpaired after the first visit (P<0.032), levels remained elevated in those who remained GDS-impaired (P=0.50). These findings are consistent with persistent monocyte/macrophage activation in neurophysiologically impaired HIV-infected individuals despite virally suppressive ART. Overall, these observations underscore the significance of monocyte/macrophage immune responses in HIV, persistent monocyte activation in HAND and the value of sCD163, as a plasma marker of neurocognitive impairment.

Soluble CD163, a Product of Monocyte/Macrophage Activation, Is Inversely Associated with Haemoglobin Levels in Placental Malaria

In Plasmodium falciparum malaria, activation of monocytes and macrophages (monocytes/macrophages) can result in the production of various inflammatory mediators that contribute to immunopathology. Soluble CD163 (sCD163) is a specific marker of monocyte/macrophage activation typically found at increased levels during various inflammatory conditions and can be associated with poor clinical outcomes. To better understand the relationships between levels of sCD163 and clinical parameters in women with placental malaria, we measured plasma sCD163 levels in maternal peripheral and placental blood compartments at delivery and determined their correlations with birth weight and maternal haemoglobin concentrations. sCD163 levels were negatively correlated with birth weight only in the placental compartment (r = −0.145, p = 0.03) and were inversely correlated with maternal haemoglobin concentrations, both in peripheral blood (r = −0.238, p = 0.0004) and in placental blood (r = −0.259, p = 0.0001). These inverse relationships suggest a potential role for monocyte/macrophage activation in the pathogenesis of malaria in pregnancy, particularly in relation to malaria-associated anaemia.

Microbial translocation and AIDS-associated lymphomas

In this issue of AIDS, Marks et al. [1] have reported significant associations between markers of microbial translocation and increased risk for non-Hodgkin’s lymphoma (NHL) in HIV-infected individuals. The authors examined prediagnostic blood samples from NHL and non-NHL HIV-infected individuals for different markers of microbial translocation. The results show that elevated plasma levels of sCD14 associated independently with 2.5-fold increased risk for NHL. The authors used Limulus Amebocyte Lysate Assay for measuring lipopolysaccharide (LPS). As plasma/serum contains substances that interfere with the assay, the authors measured percentage recovery of LPS from each sample after spiking it with LPS. Considering the samples from which they recovered the recommended (50–200) percentage of the spiked LPS, they found significant associations of the above-median values with increased (3.0-fold) risk for NHL. These results suggest, for the first time, an etiologic role of microbial translocation across gut mucosa in lymphomagenesis in HIV-infected individuals.

Increased CD163 expression is associated with acute-on-chronic hepatitis B liver failure

To assess CD163 expression in plasma and peripheral blood and analyze its association with disease in acute-on-chronic hepatitis B liver failure (ACHBLF) patients. A retrospective study was conducted from January 1, 2011 to January 1, 2012. Forty patients with ACHBLF (mean age 44.48 ± 12.28 years, range 18-69 years), 40 patients with chronic hepatitis B (CHB) (mean age 39.45 ± 12.22 years, range 21-57 years) and 20 age- and sex-matched healthy controls (mean age 38.35 ± 11.97 years, range 28-60 years) were included in this study. Flow cytometry was used to analyze the frequency of CD163+ peripheral blood mononuclear cells (PBMCs) and surface protein expression of CD163. Real-time transcription-polymerase chain reaction was performed to assess relative CD163 mRNA levels in PBMCs. Plasma soluble CD163 (sCD163) levels were measured by enzyme-linked immunosorbent assay. Clinical variables were also recorded. Comparisons between groups were analyzed by Kruskal-Wallis H test and Mann-Whitney U test. Statistical analyses were performed using SPSS 15.0 software and a P value < 0.05 was considered statistically significant. Flow cytometry showed that the population of CD163+ PBMCs was significantly greater in ACHBLF patients than in CHB patients and healthy controls (47.9645% ± 17.1542%, 32.0975% ± 11.0215% vs 17.9460% ± 6.3618%, P < 0.0001). However, there were no significant differences in mean fluorescence intensity of CD163+ PBMCs within the three groups (27.4975 ± 11.3731, 25.8140 ± 10.0649 vs 20.5050 ± 6.2437, P = 0.0514). CD163 mRNA expression in ACHBLF patients was significantly increased compared with CHB patients and healthy controls (1.41 × 10⁻² ± 2.18 × 10⁻², 5.10 × 10⁻³ ± 3.61 × 10⁻³ vs 37.0 × 10⁻⁴ ± 3.55 × 10⁻⁴, P = 0.02). Plasma sCD163 levels in patients with ACHBLF were significantly increased compared with CHB patients and healthy controls (4706.2175 ± 1681.1096 ng/mL, 1089.7160 ± 736.8395 ng/mL vs 435.9562 ± 440.8329 ng/mL, P < 0.0001). In ACHBLF patients, plasma sCD163 levels were significantly positively associated with model for end-stage liver disease scores (r = 0.5075, P = 0.008), hepatitis B virus-DNA (r = 0.6827, P < 0.0001), and negatively associated with prothrombin activity (r = -0.3348, P = 0.0347), but had no correlation with total bilirubin (r = 0.2551, P = 0.1122). Furthermore, sCD163 was obviously elevated in non-surviving patients compared with surviving patients with ACHBLF (5344.9080 ± 1589.5199 ng/mL vs 3641.7333 ± 1264.5228 ng/mL, P = 0.0321). CD163 and sCD163 may be related to disease severity and prognosis in ACHBLF patients.

Circulating levels of soluble MER in lupus reflect M2c activation of monocytes/macrophages, autoantibody specificities and disease activity.

IntroductionSystemic lupus erythematosus (SLE) is characterized by impaired efferocytosis and aberrant activation of innate immunity. We asked if shedding of MER receptor tyrosine kinase (MerTK) and AXL into soluble (s) ectodomains was related to immunological and clinical aspects of SLE.MethodsLevels of sMER and sAXL in the plasma of 107 SLE patients and 45 matched controls were measured by ELISA. In 40 consecutive SLE patients, we examined potential correlations between either sMER or sAXL and plasma levels of sCD163, a marker of M2 activation. All three soluble receptors were measured in supernatants of monocytes/macrophages cultured in various immunological conditions. Membrane expression of MerTK, AXL and CD163 was assessed by flow cytometry.ResultsBoth sMER and sAXL were associated with anti-chromatin and anti-phospholipid autoantibodies, and with hematological and renal involvement. However, sMER and sAXL did not significantly correlate with each other; sAXL correlated with growth arrest-specific 6 (Gas6), whereas sMER correlated with reduced free protein S (PROS) levels. Only sMER showed significant associations with lupus-specific anti-dsDNA, anti-Sm, anti-ribonucleoprotein (anti-RNP) and anti-Ro60 autoantibodies. Strong correlations with disease activity indices (Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), complement reduction, titer of circulating anti-dsDNA) were found for sMER, not for sAXL. Patients with active SLEDAI, nephritis, anti-dsDNA and anti-Ro60 positivity showed higher levels of sMER compared to controls. Levels of sMER, not sAXL, correlated with sCD163 levels, and these correlated with SLEDAI. Production of sMER and sCD163 occurred under “M2c” polarizing conditions, whereas sAXL was released upon type-I IFN exposure.ConclusionsAlterations in homeostasis of anti-inflammatory and efferocytic “M2c” monocytes/macrophages may have a role in immunopathogenesis of SLE.

The early Th17/Treg ratio predicts the immune activation set point in patients with primary HIV infection

BACKGROUND: Persistent systemic immune activation plays a central role in the pathogenesis of HIV disease. Impairment of the intestinal barrier and subsequent microbial translocation might be involved in chronic immune activation. Th17 cells are important in the maintenance of intact epithelium and host defense against extracellular pathogens. The ratio between the two closely related CD4 subsets Th17 and Tregs has been recently found to shrink with HIV/SIV disease progression. The aim of the study was to analyze, in patients with early primary HIV infection (PHI), the relationship between Th17/Treg ratio and the immune activation set point, known to predict disease progression. METHODS: 27 patients with early PHI were included in a prospective longitudinal study and followed-up for 6 months. T-cell activation and CD4+CD25+CD127lowFoxp3+ Treg frequency were assessed on fresh PBMC. Th17 cells were quantified by intracellular cytokine staining on sorted peripheral CD4 T cells stimulated with PMA/ionomycin for 5h. Correlations were assessed using spearman non-parametric tests. Plasma I-FABP, a marker of mucosal damages and soluble CD14 (sCD14) were measured by ELISA. RESULTS: A strong negative relationship was found at baseline between the Th17/Treg ratio and the proportion of activated CD8 T cells expressing CD38/HLA-DR (p=0.008) or Ki-67 (P=0.001). At baseline, Th17/Treg ratios also negatively correlated with sCD14 plasma levels (p=0.003). I-FABP levels, which were similar to controls at baseline, increased at month 6. The Th17/Treg ratio at baseline (but not the proportion of Th17 cells) negatively correlated with the frequency of HLA-DR+CD38+ or Ki-67+ CD8 T cells at month 6, defining the immune activation set point (p=0.02 and p=0.0005 respectively). sCD14 plasma levels were also found to predict the immune set point (p=0.02). CONCLUSION: Our data do not support early mucosal damages in PHI. However, the early Th17/Treg balance correlates with sCD14 levels and predicts the immune activation set point.

In vitro soluble CD30 levels in patients with chronic stable coronary artery disease.

The CD30 antigen seems to play a costimulatory role in maintaining the physiological balance between T-helper (Th)1/Th2 immune responses. In this study, plasma and in vitro soluble CD30 (sCD30) secretion was investigated in patients with coronary artery disease (CAD) as a plausible marker of dysregulated immune response.Twenty one patients with angiographically confirmed CAD and 31 healthy controls took part in this study. The levels of the activation marker sCD30 were determined in plasma and phytohaemagglutinin (PHA)-stimulated and unstimulated peripheral blood mononuclear cell cultures by ELISA. Plasma sCD30 levels did not differ significantly between the patients and controls. However, spontaneous sCD30 secretion was significantly lower in patients with CAD compared to controls (p < 0.001). The soluble CD30 levels were significantly increased in the supernatant of PHA-stimulated PBMCs compared to unstimulated cultures in both groups of patients and controls (p < 0.001). PHA-stimulated sCD30 secretion was found to be lower in patients compared to controls; however, the difference was not statistically significant. Plasma sCD30 levels were not statistically different in patients with chronic stable CAD, a well-known Th1-mediated disease, compared to controls; whereas decreased spontaneous and PHA-stimulated sCD30 secretion in patients with CAD might indicate the progressive shift towards a Th1 immune response.

In vitro soluble CD30 levels in patients with chronic stable coronary artery disease.

The CD30 antigen seems to play a costimulatory role in maintaining the physiological balance between T-helper (Th)1/Th2 immune responses. In this study, plasma and in vitro soluble CD30 (sCD30) secretion was investigated in patients with coronary artery disease (CAD) as a plausible marker of dysregulated immune response.Twenty one patients with angiographically confirmed CAD and 31 healthy controls took part in this study. The levels of the activation marker sCD30 were determined in plasma and phytohaemagglutinin (PHA)-stimulated and unstimulated peripheral blood mononuclear cell cultures by ELISA. Plasma sCD30 levels did not differ significantly between the patients and controls. However, spontaneous sCD30 secretion was significantly lower in patients with CAD compared to controls (p < 0.001). The soluble CD30 levels were significantly increased in the supernatant of PHA-stimulated PBMCs compared to unstimulated cultures in both groups of patients and controls (p < 0.001). PHA-stimulated sCD30 secretion was found to be lower in patients compared to controls; however, the difference was not statistically significant. Plasma sCD30 levels were not statistically different in patients with chronic stable CAD, a well-known Th1-mediated disease, compared to controls; whereas decreased spontaneous and PHA-stimulated sCD30 secretion in patients with CAD might indicate the progressive shift towards a Th1 immune response.

Plasma sCD14 Is a Biomarker Associated With Impaired Neurocognitive Test Performance in Attention and Learning Domains in HIV Infection

Mild forms of HIV-associated neurocognitive disorders (HAND) remain prevalent in the era of combination antiretroviral therapy (cART). Although elevated lipopolysaccharide (LPS) and immune activation are implicated in HAND pathogenesis, relationships of LPS and inflammatory markers to mild forms of HAND or impairment in specific cognitive domains are unknown. To examine these relationships, we compared plasma soluble CD14 (sCD14), CCL2, and LPS levels with neurocognitive test scores in a cART era cohort. We analyzed plasma from HIV+ subjects (n = 97) with nadir CD4 counts <300 and high frequency of hepatitis C virus coinfection and illicit drug use for relationships between sCD14, CCL2, and LPS levels and neurocognitive test scores. Plasma sCD14 levels were higher in subjects with test scores indicating global impairment (P = 0.007), particularly in attention and learning domains (P = 0.015 and P = 0.03, respectively), regardless of HAND diagnosis. Plasma sCD14 levels correlated inversely with global, attention, and learning T scores (P = 0.036, 0.047, and 0.007, respectively) and yielded higher area under receiver operating characteristic values for predicting impaired scores than single-marker models based on plasma or cerebrospinal fluid viral load or CD4 count (area under receiver operating characteristic values = 0.71, 0.81, and 0.71, respectively) and in 4-marker models based on plasma sCD14 and 3 conventional markers compared with the 3-marker models. Plasma sCD14 is a biomarker associated with impaired neurocognitive testing in attention and learning domains in HIV-infected individuals with advanced disease, suggesting involvement of cortical and limbic pathways by inflammatory processes in the cART era. Plasma sCD14 is a potential biomarker to monitor HAND progression and therapeutic responses.

Host Response to Translocated Microbial Products Predicts Outcomes of Patients With HBV or HCV Infection

Chronic infection with hepatitis B or C virus (HBV or HCV) is a leading cause of cirrhosis by unknown mechanisms of pathogenesis. Translocation of gut microbial products into the systemic circulation might increase because of increased intestinal permeability, bacterial overgrowth, or impaired clearance of microbial products by Kupffer cells. We investigated whether the extent and progression of liver disease in patients with chronic HBV or HCV infection are associated with microbial translocation and subsequent activation of monocytes. In a retrospective study, we analyzed data from 16 patients with minimal fibrosis, 68 with cirrhosis, and 67 uninfected volunteers. We analyzed plasma levels of soluble CD14 (sCD14), intestinal fatty acid binding protein, and interleukin-6 by enzyme-linked immunosorbent assay, and lipopolysaccharide (LPS) by the limulus amebocyte lysate assay, at presentation and after antiviral treatment. Compared with uninfected individuals, HCV- and HBV-infected individuals had higher plasma levels of LPS, intestinal fatty acid binding protein (indicating enterocyte death), sCD14 (produced upon LPS activation of monocytes), and interleukin-6. Portal hypertension, indicated by low platelet counts, was associated with enterocyte death (P=.045 at presentation, P<.0001 after therapy). Levels of sCD14 correlated with markers of hepatic inflammation (P=.02 for aspartate aminotransferase, P=.002 for ferritin) and fibrosis (P<.0001 for γ-glutamyl transpeptidase, P=.01 for alkaline phosphatase, P<.0001 for α-fetoprotein). Compared to subjects with minimal fibrosis, subjects with severe fibrosis at presentation had higher plasma levels of sCD14 (P=.01) and more hepatic CD14+ cells (P=.0002); each increased risk for disease progression (P=.0009 and P=.005, respectively). LPS-induced local and systemic inflammation is associated with cirrhosis and predicts progression to end-stage liver disease in patients with HBV or HCV infection.

In vitro and in vivo evidence for the role of elastase shedding of CD163 in human atherothrombosis

CD163 is a macrophage receptor for haemoglobin-haptoglobin (Hb-Hp) complexes, responsible for the clearance of haemoglobin. We hypothesized that production of soluble CD163 (sCD163) may be due to proleolytic shedding of membrane CD163 by neutrophil elastase, reported to be increased in culprit atherosclerotic plaques. We analysed the relationship between CD163 solubilization and elastase in vitro, in macrophage culture, ex vivo in human atherosclerotic plaque samples, and in vivo, in plasma of patients with coronary artery disease. Neutrophil elastase was shown to enhance CD163 shedding and to decrease the uptake of Hb-Hp complexes by cultured macrophages. In addition, cultured carotid endarterectomy samples showing features of intraplaque haemorrhage released more sCD163 and elastase/α1-antitrypsin (α1-AT) complexes than non-haemorrhagic plaques (n= 44). Plasma levels of sCD163 and neutrophil elastase (complexed with α1-AT) were measured in patients with an acute coronary syndrome (ACS, n= 42), stable angina pectoris (SAP, n= 28), or normal coronary angiograms without subclinical atherosclerosis (n= 21). Acute coronary syndrome patients had higher sCD163 and elastase/α1-AT complexes plasma concentrations than subjects without coronary atherosclerosis. Circulating sCD163 and elastase/α1-AT complexes were positively correlated in patients with ACS (r = 0.56, P< 0.0002) and SAP (r = 0.62, P< 0.0005). Our results suggest that neutrophil elastase promotes CD163 shedding, resulting in a decreased clearance of Hb by macrophages, which may favour plaque destabilization. This may be reflected by increased plasma levels of sCD163 and elastase/α1-AT complexes which are positively correlated in patients with coronary artery disease.

Reduction of HIV-1 innate immune activation by protease inhibitors (154.15)

Abstract HIV-1-associated innate immune activation is caused by viral replication and/or microbial substances that leak from the gut lumen into the circulation (microbial translocation). Consequences of the ensuing HIV-1-associated inflammation range from neurocognitive impairment to cardiovascular disease where macrophages play a central role. HIV-1 therapy is evaluated based on suppression of viremia and restoration of CD4 T cells, while the effects of therapy on innate immune activation are rarely considered. The current study assessed the effects of protease inhibitors on macrophage activation ex vivo and in vivo. Nelfinavir [NFV] and tipranavir [TPV] inhibited LPS activation of human macrophages ex vivo as measured by reduced secretion of LPS-binding protein soluble CD14 [sCD14] and pro-inflammatory cytokines IL-6 and TNF. Cytokine secretion was inhibited prior to transcription by modulation of toll-like receptor signaling pathways. In vivo, NFV-treated HIV-1-infected patients presented with significantly reduced monocyte/macrophage activation as measured by a greater reduction in sCD14 plasma levels compared to those treated with indinavir or ritonavir. These data suggest that anti-inflammatory effects of NFV or TPV may augment efficacy of HIV-1 treatment by targeting HIV-1-assocated innate immune activation. Delineation of cellular targets of NFV or TPV will lead to novel approaches to suppress innate immune activation in HIV-1, other infectious diseases or autoimmunity.

Role of the CD14 C(−260)T promoter polymorphism in determining the first clinical manifestation of coronary artery disease

Acute coronary syndromes (ACS) and chronic stable angina represent extremes of the clinical spectrum of coronary artery disease (CAD). It is unknown whether genetic determinants affect the first clinical manifestation of CAD. We evaluated the role of the C(-260)T polymorphism in the promoter of the CD14-receptor gene, an important mediator of the inflammatory response to lipopolysaccharide. CD14 C(-260)T polymorphism was assessed in 100 patients with an acute presentation of CAD (group 1), 66 patients with stable presentation (group 2) and 88 healthy people (group 3); all patients were whites. In addition, baseline sCD14 plasma levels, and interleukin-6 production by circulating monocytes after in-vitro stimulation with lipopolysaccharide (1 ng/ml) were assessed. T/T homozygosis was more frequent in group 1 (36%, P < 0.001 versus others). Interleukin-6 production was higher in T/T homozygotes (median 4092.4; range 387-10 582 pg/ml) than in C/T heterozygotes (median 2442, range 40.5-9625 pg/ml, P < 0.001) and C/C homozygotes (median 3277.5; range 374.4-6250 pg/ml, P < 0.001). At multivariate analysis, T/T homozygosis and interleukin-6 production were independent predictors of acute presentation of CAD. The present study shows that genetic factors that influence the reactivity of inflammatory cells may play a role in determining the first clinical presentation of CAD.

CD14 Promoter Polymorphism (− 159C→t) is Not Associated with Myocardial Infarction or Coronary Artery Disease in Patients with Assumed High Genetic Risk

Inflammation plays a major role in the pathogenesis of coronary artery disease (CAD) and myocardial infarction (MI). CD14 is the receptor for bacterial lipopolysaccharide in monocytes and mediates the production of proinflammatory cytokines. The promoter of the CD14 gene has a polymorphic site in position - 159 (C-->T) and T-homozygotes have been shown to express higher amounts of CD14 by some investigators. We and others have found an association of the T-allele with past MI in former studies, but reports in the literature are contradictory. We investigated a study group with an assumed high genetic risk by selecting 200 patients suffering from angiographically verified CAD or MI who were younger than 50 years or who had only one or no risk factor (hypertension, smoking, elevated body mass index, impaired glucose tolerance or elevated cholesterol levels). We used 252 healthy subjects as controls. Additionally, the levels of soluble (s) CD14 in plasma and amount of membranous (m) CD14 on the surface of monocytes were determined in different genotypes. We found no association of either genotype with CAD, extent of CAD, or a history of MI. No significant correlation was found after adjustment for vascular risk factors. In addition, no significant differences in the density of monocyte mCD14 or in plasma levels of sCD14 were detectable among the various genotypes. The assumed weak association of the TT-genotype of the CD14 promoter polymorphism with MI could not be not established in a well-defined group of young patients with a high genetic risk. The association of the polymorphism with expression of sCD14 or mCD14 was not confirmed.

Use of atorvastatin as an anti‐inflammatory treatment in Crohn's disease

Experimental and clinical investigations have revealed that statins can downregulate both acute and chronic inflammatory processes. Whether statins express anti-inflammatory activities in the treatment of Crohn's disease is unknown. Ten patients were given 80 mg atorvastatin once daily for 13 weeks and then followed up for 8 weeks after the treatment. The anti-inflammatory effects of statin were assessed by measuring levels of plasma C-reactive protein (CRP), soluble (s) CD14, tumour necrosis factor (TNF)-alpha, sTNFRI and II, CCL2 and 8 and the mucosal inflammation by faecal calprotectin. Circulating monocytes were subgrouped and their chemokine receptor expression of CCR2 and CX(3)CR1 were analysed. In 8 of 10 patients, atorvastatin treatment reduced CRP (P=0.008) and sTNFRII (P=0.064). A slight decrease in plasma levels of sCD14, TNF-alpha and sTNFRI was observed in 7/10 patients and faecal calprotectin was reduced in 8/10 patients. We also observed that the treatment diminished expression of CCR2 and CX(3)CR1 on monocyte populations (P=0.014). At the follow-up visit, 8 weeks after the atorvastatin treatment was terminated, CRP levels had returned to those seen before the treatment. Our findings imply that atorvastatin therapy reduces inflammation in patients with Crohn's disease and, therefore, encourage further investigations of statin-mediated protective effects in inflammatory bowel diseases.