Serum Levels Of CD163 Research Articles

IL-21 induction of CD4+ T cell differentiation into Th17 cells contributes to bleomycin-induced fibrosis in mice.

Systemic sclerosis (SSc) is a connective tissue disease characterized by fibrosis of the skin and internal organs. Th17 cells and interleukin-17 (also called IL-17A) have been found to be increased in peripheral blood and skin in patients with SSc. IL-21 is a potent inducer of Th17 differentiation that is produced by activated T cells, and whose relationship with Th17 cells in SSc is unclear. Here, using a bleomycin (BLM)-induced mouse model of skin fibrosis, we detected the frequency of CD4+/IL-17+ (Th17) cells, CD4+/IL-21+ T cells and IL-21+ Th17 cells in peripheral blood, skin and lungs, as well as the serum content of IL-17A and IL-21. In addition, we assessed the differentiation of CD4+ T cells cultured from these mice into Th17 cells in response to treatment with IL-21. Compared with the control mice, Th17 cell counts and IL-17A levels were significantly increased and correlated with inflammatory and fibrotic indices in the skin and lungs of the BLM-induced fibrosis mice. Moreover, serum levels of CD4+/IL-21+ T cells, IL-21+ Th17 cells, and IL-21 were significantly increased in these mice, and correlated positively with serum levels of Th17 cells. In vitro experiments showed that IL-21 treated CD4+ T cells derived from BLM-induced mice differentiated into Th17 cells. Our results indicate that Th17 cells and IL-17A contributes to inflammatory and fibrotic processes in the skin and lungs in a BLM-induced mouse model of SSc. Moreover, the expansion of the Th17 cell population may be subsequent to IL-21 promotion of the differentiation of CD4+ T cells in these mice.

Serum levels of CD163 and TWEAK in patients with pulmonary arterial hypertension

BackgroundInflammation may play a pivotal role in the pathogenesis of pulmonary arterial hypertension (PAH). We evaluated the concentrations of serum sTWEAK, its scavenger receptor sCD163 and sTWEAK/sCD163 ratio in patients with PAH. DesignThe study enrolled 26 stable patients with PAH confirmed by right heart catheterization and 24 healthy volunteers matched for age, sex and body weight. All patients underwent transthoracic echocardiography, cardiopulmonary exercise test, 6-min walk test, measurement of lung diffusing capacity for the carbon monoxide (DLCO) and venous blood tests. Concentrations of sTWEAK and sCD163 were determined using ELISA kits. ResultsThe PAH patients were characterized by significantly higher median serum sCD163 levels (1072 vs 890ng/ml, p=0.04) together with lower serum sTWEAK concentrations (200 vs 278.1pg/ml, p=0.003) comparing to control subjects. sTWEAK/sCD163 ratio was therefore significantly lower in PAH group (0.18 vs 0.33, p=0.0005). No correlation was found between sTWEAK and sCD163 concentrations in both groups. We observed statistically significant inverse correlation between peak VO2 consumption and sCD163 concentrations (r=−0.52, p<0.05) and positive with sTWEAK/sCD163 ratio (r=0.45, p<0.05) in PAH group. Moreover, sTWEAK/sCD163 ratio positively correlated with % of predicted values of DLCO (r=0.42, p<0.05). ConclusionsPatients with PAH present altered serum sTWEAK and sCD163 levels. The sTWEAK/sCD163 ratio appears to be a better indicator of the severity of PAH as compared to sTWEAK or sCD163 alone. The exact role of sCD163 or interaction between CD163 and sTWEAK in the initiation or progression of PAH as well as their potential prognostic significance remains to be established.

Soluble CD163 Is Associated With CD163 mRNA Expression in Adipose Tissue and With Insulin Sensitivity in Steady-State Condition but Not in Response to Calorie Restriction

Soluble CD163 (sCD163) was suggested as a biomarker of insulin sensitivity and CD163 mRNA expression representing macrophage content in adipose tissue (AT). The aim of this study was to investigate, in cross-sectional and prospective design, the relationship between sCD163 circulating levels and CD163 mRNA expression in adipose tissue and insulin sensitivity assessed by euglycemic-hyperinsulinemic clamp. Two cohorts of subjects were examined in the study. Cohort 1 included 42 women with a wide range of body mass index (17-48 kg/m(2)); cohort 2 included 27 obese women who followed a dietary intervention consisting of 1 month of a very low-calorie diet and 5 months of a weight-stabilization period. Serum levels of CD163 and mRNA expression of CD163 and CD68 in sc and visceral (visc) AT were determined, and insulin sensitivity [expressed as glucose disposal rate (GDR)] was measured in cohort 1. In cohort 2, serum levels of CD163, mRNA expressions of CD163, CD68, and CD163-shedding factors [TNF-α-converting enzyme (TACE) and tissue inhibitor of metalloproteinase (TIMP3)] in sc AT were examined and GDR was measured before and during dietary intervention. In cohort 1, circulating sCD163 correlated with CD163 mRNA levels in both sc and visc AT. sCD163 and CD163 mRNA expression in both fat depots correlated with GDR. In cohort 2, the diet-induced changes of sCD163 levels did not correlate with those of CD163, CD68, TACE, and TIMP3 mRNA levels. Although the pattern of the diet-induced change of sCD163 paralleled that of GDR, there was no correlation between the changes of these two variables. sCD163 correlates with CD163 mRNA expression in sc and visc AT and with whole-body insulin sensitivity in the steady-state condition. These associations are not observed with respect to the diet-induced changes during a weight-reducing hypocaloric diet.

Absolute Monocyte Count and Serum CD14 As Prognostic Markers In Chronic Lymphocytic Leukemia

IntroductionAlthough chronic lymphocytic leukemia (CLL) is a generally indolent malignancy, there is a spectrum of disease aggressiveness. Clinical and molecular prognostic markers are helpful for the clinician and for the patient, in terms of disease management and life planning. Additional prognostic markers can help with further risk stratification, especially for CLL patients with “low-risk” disease. The prognostic value of absolute monocyte count (AMC) has been evaluated in various malignancies, including CLL where elevated AMC at diagnosis was shown to be associated with rapid time to first therapy (TTT), and in one series, inferior overall survival (OS). The mechanism by which elevated AMC is associated with worse treatment free survival is not known. However, CD14, which is secreted by monocytes, improves in vitro CLL cell survival, and is found at high levels in the serum of CLL patients. We hypothesized that elevated AMC at the time of CLL diagnosis is associated with inferior survival and that elevated serum CD14 is associated with high AMC and worse survival. MethodsCLL patients followed at the Duke University and Durham VA Medical Centers and enrolled in an IRB approved protocol to collect clinical data and blood samples were evaluated. We selected patients for whom AMC was measured between three months prior to diagnosis to three months after diagnosis. We evaluated the correlation between AMC and TTT and OS, with AMC as a continuous and as a dichotomized variable. We also assessed the prognostic capability of AMC in relation to other clinical and molecular prognostic markers, such as Rai stage, race, interphase cytogenetics by FISH, CD38 and ZAP70 expression, and IGHV mutation status. We measured serum CD14 levels using an ELISA assay, and evaluated the correlation between CD14 levels and clinical outcomes or AMC. Cox proportional hazard models were used to evaluate time to event outcomes, Wilcoxon rank sum test and Kruskal-Wallis rank sum test were used to compare AMC to other prognostic markers, and Pearson's correlation test was used to compare continuous variables. ResultsFrom a cohort of over 600 CLL patients, we selected 222 patients with AMC measured ± three months from the date of diagnosis. AMC ranged from 0 to 7.63 cells/mL. With a median follow up of 5.2 years (range 0.1 – 18.2), 102 patients (46%) had been treated, and 59 patients (27%) died. This was not significantly different from the entire cohort. Higher AMC was significantly correlated with shorter TTT (p = 0.002, hazard ratio 1.37, 95% CI 1.12 – 1.68) and inferior OS (p = 0.017, hazard ratio 1.39, 95% CI 1.06 – 1.83). There was no significant difference in AMC in patients stratified by Rai stage, race, interphase cytogenetics, CD38 or ZAP70 expression, or IGHV mutation status. When combined with molecular prognostic markers (IGHV mutation status, CD38 and ZAP70 expression, and interphase cytogenetics) in multivariate models, AMC retained significant prognostic power for TTT and OS. The serum soluble CD14 levels were measured in CLL patients from this cohort, with a mean CD14 level of 2.3 ug/mL. The prognostic significance of serum CD14 and correlation with AMC will be presented. ConclusionsAbsolute monocyte count at the time of CLL diagnosis is associated with inferior clinical outcomes – both TTT and OS. These results confirm and extend other reports evaluating the prognostic significance of circulating monocytes in CLL. Our evaluation of serum CD14, a monocyte-derived secreted protein that promotes CLL cell viability, in concert with AMC may provide a possible explanation for the associations identified in this cohort of patients. As an easily measured clinical marker, AMC can be readily used and/or combined with other prognostic markers to improve risk stratification and patient counseling at the time of diagnosis. Disclosures:No relevant conflicts of interest to declare.

Fuzhengpaidu granule Regulates Immune Activation Molecules CD38 and human leukocyte antigen-D related on CD4+ and CD8+ T Cells in Patients with Acquired immunodeficiency syndrome/human immunodeficiency virus

ObjectiveTo evaluate the effect of Fuzhengpaidu granule (FZPDG) on immune activation molecules CD38 and human leukocyte antigen-D related (HLA-DR) on CD4+ and CD8+ cells in HIV/AIDS patients, and to explore the underlying mechanism of this therapy. MethodsPlasma changes in CD3+, CD4+, CD8+, CD3+CD4+CD38+, CD3+CD4+HLA-DR+, CD3+CD8+CD38+, and CD3+CD8+HLA-DR+ levels in HIV/AIDS patients treated with FZPDG for six months were examined by flow cytometry and compared with levels in healthy controls. ResultsThe clinical trial included 34 outpatients with HIV/AIDS. Before treatment, plasma levels of CD38+ and HLA-DR+ on CD4/CD8 cells were higher than those in 28 health controls (P<0.05). There were no significant changes in serum levels of CD3+, CD4+, and CD8+ T cells between pretreatment baseline versus after treatment, which were (82.85±5.41)%, 14.57±10.31% and (54.55±11.43)% before treatment and (79.15±8.21)%, (19.96±9.58)% and (56.36±11.67)% after treatment, respectively (P>0.05). Plasma levels of CD3+CD4+CD38+ and CD3+CD4+HLA-DR+ were (2.38±2.22)% and (7.84±5.49)% before treatment and (1.25±0.83)% and (2.59±1.01)% after treatment, respectively. Plasma levels of CD3+CD8+CD38+ and CD3+CD8+HLA-DR+ were (41.40±13.45)% and (17.78±11.29)% before treatment, which changed to (27.10±10.17)% and (3.80±2.39)% after treatment, respectively (P<0.05). ConclusionHIV/AIDS patients exhibited an immune activation profile following FZPDG treatment. A potential mechanism of action for FZPDG appears to lie in its ability to up-regulate CD38 and HLA-DR levels on CD4+ T cells, and down-regulate them on CD8+ cells, thereby modulating immune activation of CD4+ and CD8+ T cells.

Reduced expressions of Fas and Bcl-2 proteins in CD14+ monocytes and normal CD14 soluble levels in juvenile systemic lupus erythematosus

In order to evaluate Fas and Bcl-2 expressions in CD14+ monocytes, to measure soluble CD14 serum levels and to analyze the relationships with lupus nephritis and disease activity, we enrolled 41 patients with juvenile systemic lupus erythematosus (JSLE) and 27 healthy volunteers. Disease activity was determined by SLEDAI score. Peripheral monocytes were stained for CD14, Fas and Bcl-2 molecules, and cellular expressions were determined by flow cytometry. Soluble CD14 levels were measured by a quantitative ELISA kit. JSLE patients, those with active disease and those with nephritis, presented significantly reduced expressions of Fas and Bcl-2 proteins in CD14+ monocytes compared with healthy controls. Significant inverse correlations between percentages of CD14+Fas+ cells, SLEDAI score and anti-dsDNA antibodies were observed. JSLE patients had soluble CD14 levels similar to controls, although sCD14 levels positively correlated with ESR, but not with SLEDAI score. JSLE patients with nephritis also presented sCD14 levels similar to controls. In conclusion, the reduced expressions of Fas and Bcl-2 proteins in CD14+ monocytes from JSLE patients depict that monocyte apoptotic mechanisms may be important in lupus pathogenesis.

Serum and Tissue CD23, IL‐15, and FasL in Cow's‐Milk Protein–sensitive Enteropathy and in Coeliac Disease

The aim of the study was to explore pathogenesis and find new serum markers for cow's-milk-sensitive enteropathy (CMSE) and coeliac disease (CD). We assessed the intestinal expression and serum concentration of CD23, IL-15, and FasL. We hypothesised that the serum levels of CD23, a protein expressed in the lymphoid follicles, would be associated with lymphonodular hyperplasia (LNH), a feature characteristic of CMSE. We also presumed that interleukin (IL)-15 and FasL, functionally connected with proliferation and apoptosis of the intraepithelial lymphocytes (IELs), would relate with the increased numbers of IELs present in both CMSE and CD. Twenty-three children with CMSE, 20 with untreated CD, and 14 controls were studied for CD3, α/β- and γ/δ-expressing IELs, and for duodenal and ileal expression of CD23, FasL, and IL-15 by immunohistochemistry, and for serum concentration of sCD23, sFasL, and sIL-15 by enzyme-linked immunosorbent assay. There was a trend for increase in sCD23 serum levels in untreated CMSE and in CD (P = 0.074; P = 0.077). CD23 was expressed in the mucosal germinal centres, but sCD23 was not related to presence of LNH. In CMSE, there was a trend for increase in serum sFasL (P = 0.07) and high levels associated with LNH (P = 0.025) and correlated with the IEL numbers (P < 0.05). Mucosal high endothelial venules adjacent to lymphoid follicles showed an intensive FasL expression. Serum sCD23 shows a trend of increment in CMSE and CD, and in the latter, sCD23 level may provide information about the severity of villous atrophy. In CMSE, high serum sFasL indicates both LNH and an increase of IELs, suggesting importance of FasL-mediated mechanisms in the pathogenesis of these features characteristic of CMSE. Further studies are necessary to evaluate whether intensive FasL expression in mucosal high endothelial venules presents a regulatory element in mucosal immunity.

CD14 polymorphisms and serum CD14 levels through childhood: A role for gene methylation?

CD14 is a pattern-recognition receptor for environmental LPS, and engagement of the CD14-LPS complex activates innate host defense mechanisms. Single nucleotide polymorphisms (SNPs) in the CD14 gene have been associated with soluble CD14 (sCD14) levels, but inconsistencies between studies suggest the presence of regulatory mechanisms hitherto not well understood. We sought to investigate possible associations between CD14 SNPs and sCD14 levels at different time points in childhood (at birth [cord blood] and 2 and 10 years) and to explore whether these associations were related to CD14 gene methylation. Four SNPs, rs2569191 (-1145GA), rs5744455 (-550CT or -651CT), rs2569190 (-159CT or -260CT), and rs4914 in CD14 were genotyped in 762 children from the Environmental and Childhood Asthma study. Genotype frequencies were analyzed for association with sCD14 levels in 660 babies, 346 children at age 2 years, and 360 children at age 10 years. In a subgroup of 157 children with DNA available at both 2 and 10 years of age, CD14 methylation patterns were determined and analyzed against detected CD14 gene-sCD14 associations. rs2569191, rs5744455, and rs2569190 were associated with sCD14 levels at birth and 2 years, but only rs5744455 was associated with sCD14 levels at 10 years. CD14 methylation increased significantly from age 2 to 10 years, and the level of methylation was inversely correlated with sCD14 levels at 10 years. The reduced effect of CD14 polymorphisms on sCD14 levels from early to late childhood paralleled a small but significant increase in CD14 methylation during the same period.

Identification of Diagnostic Biomarkers for Infection in Premature Neonates

Infection is a leading cause of neonatal morbidity and mortality worldwide. Premature neonates are particularly susceptible to infection because of physiologic immaturity, comorbidity, and extraneous medical interventions. Additionally premature infants are at higher risk of progression to sepsis or severe sepsis, adverse outcomes, and antimicrobial toxicity. Currently initial diagnosis is based upon clinical suspicion accompanied by nonspecific clinical signs and is confirmed upon positive microbiologic culture results several days after institution of empiric therapy. There exists a significant need for rapid, objective, in vitro tests for diagnosis of infection in neonates who are experiencing clinical instability. We used immunoassays multiplexed on microarrays to identify differentially expressed serum proteins in clinically infected and non-infected neonates. Immunoassay arrays were effective for measurement of more than 100 cytokines in small volumes of serum available from neonates. Our analyses revealed significant alterations in levels of eight serum proteins in infected neonates that are associated with inflammation, coagulation, and fibrinolysis. Specifically P- and E-selectins, interleukin 2 soluble receptor alpha, interleukin 18, neutrophil elastase, urokinase plasminogen activator and its cognate receptor, and C-reactive protein were observed at statistically significant increased levels. Multivariate classifiers based on combinations of serum analytes exhibited better diagnostic specificity and sensitivity than single analytes. Multiplexed immunoassays of serum cytokines may have clinical utility as an adjunct for rapid diagnosis of infection and differentiation of etiologic agent in neonates with clinical decompensation.

Serum CD14 levels in poly traumatized and severely burned patients

Recently it has been demonstrated that the CD14 molecule which is expressed on monocytes and macrophages serves as a receptor for lipopolysaccharide (LPS) bound to LPS-binding protein (LBP) and thus mediates LPS-induced tumour necrosis factor (TNF) production. Here we report that CD14 is found as a soluble (s) molecule in serum. In healthy volunteers sCD14 levels (mean +/- s.e.m.) were 3.7 +/- 0.05 micrograms/ml (n = 30, 25-50 years of age) as determined by ELISA (detection limit 20 ng/ml serum) using two monoclonal antibodies in a sandwich technique. In polytraumatized patients (n = 16) significantly decreased levels (1.7 +/- 0.3) were detected immediately after the trauma, which increased to 4.9 +/- 0.3 micrograms/ml within the first 6 days post trauma. sCD14 remained elevated during the first 14 days post trauma in patients with the most severe injuries (injury severity score greater than 45 points), whereas a return to normal levels was observed in patients with an injury score of less than 45 points. In addition, the levels of the high-density lipoproteins that partially inactivate free endotoxin are significantly decreased post trauma. No correlation between parameters of inflammation (C3a and neopterin levels, leucocyte counts, amount of band cells), liver function and sCD14 levels was established. Comparable to polytraumatized patients, increased sCD14 serum levels were observed in five patients with burn trauma (burned area greater than 35%) within the second week post trauma when clinical signs of septicaemia were evident.

Study on clinical effect and mechanism of Jianpi Qingre Huayu Recipe (健脾清热化瘀方) in treating patients with gastric ulcer

To study the effects of Jianpi Qingre Huayu Recipe in curing gastric ulcer and to preliminarily probe into its pathogenic mechanism. Fifty patients with gastric ulcer of Pi -insufficiency and stasis-heat syndrome type were assigned to the treated group (30 patients) and the control group (20 patients). They were treated respectively with JQH and Ranitidine. At the same time, another group consisting of 20 healthy persons was set up for normal control. The clinical effect on gastroscopic figure and traditional Chinese medicine (TCM) syndrome were observed. Changes of T-cell subsets and interleukin-8 (IL-8) in serum as well as IL-8 in mucosa around the gastric ulcer were determined before and after treatment by flow cytometry and ELISA. Comparison of the total effective rate on gastroscopic figure in the treated group and the control group (86.7% vs 80.0%) showed insignificant difference, but the cure rate and markedly effective rate in the former (50.0% and 20.0%) was higher than that in the latter (40.0% and 15.0%) respectively. Comparison of the total effective rate on TCM syndrome in the treated group and in the control group (96.7% vs 70.0%) showed insignificant difference, but the cure rate and markedly effective rate in the former (63.3% and 23.3%) was higher than that in the latter (50.0% and 20.0%) respectively. Serum levels of CD3+, CD4+, CD8+ got restored to normal range in the treated group after treatment but it was not so in the control group. IL-8 level in gastric mucosa was improved in both groups but the improvement in the treated group was better. JQH could effectively treat gastric ulcer and partly reduce its recurrence through improving patients' immune function.

Association of CD14 Promoter Polymorphism with Otitis Media and Pneumococcal Vaccine Responses

Innate immunity is of particular importance for protection against infection during early life, when adaptive immune responses are immature. CD14 plays key roles in innate immunity, including in defense against pathogens associated with otitis media, a major pediatric health care issue. The T allele of the CD14 C-159T polymorphism has been associated with increased serum CD14 levels. Our objective was to investigate the hypothesis that the CD14 C-159T allele is protective against recurrent acute otitis media in children. The association between the CD14 promoter genotype and the number of acute otitis media episodes was evaluated both retrospectively and prospectively in a cohort of 300 children. Serotype-specific immunoglobulin G (IgG) antibody responses after pneumococcal vaccinations were examined according to CD14 genotype to compare immune responsiveness across genotypes. An age-dependent association was found: compared with that for CC homozygotes aged between 12 to 24 months, TT homozygotes had fewer episodes of acute otitis media (79 versus 41%, respectively; P = 0.004); this relationship was absent in older children. Additionally, TT homozygotes showed higher serotype-specific anti-pneumococcal IgG antibody levels. Our data suggest that genetic variation in CD14, a molecule at the interface of innate and adaptive immune responses, plays a key role in the defense against middle ear disease in childhood and in pneumococcal vaccine responsiveness. These findings are likely to be important to these and other immune-mediated outcomes in early life.

Association of CD14 Promoter Polymorphism with Otitis Media and Pneumococcal Vaccine Responses

Innate immunity is of particular importance for protection against infection during early life, when adaptive immune responses are immature. CD14 plays key roles in innate immunity, including in defense against pathogens associated with otitis media, a major pediatric health care issue. The T allele of the CD14 C-159T polymorphism has been associated with increased serum CD14 levels. Our objective was to investigate the hypothesis that the CD14 C-159T allele is protective against recurrent acute otitis media in children. The association between the CD14 promoter genotype and the number of acute otitis media episodes was evaluated both retrospectively and prospectively in a cohort of 300 children. Serotype-specific immunoglobulin G (IgG) antibody responses after pneumococcal vaccinations were examined according to CD14 genotype to compare immune responsiveness across genotypes. An age-dependent association was found: compared with that for CC homozygotes aged between 12 to 24 months, TT homozygotes had fewer episodes of acute otitis media (79 versus 41%, respectively; P = 0.004); this relationship was absent in older children. Additionally, TT homozygotes showed higher serotype-specific anti-pneumococcal IgG antibody levels. Our data suggest that genetic variation in CD14, a molecule at the interface of innate and adaptive immune responses, plays a key role in the defense against middle ear disease in childhood and in pneumococcal vaccine responsiveness. These findings are likely to be important to these and other immune-mediated outcomes in early life.

CD14 Promoter Polymorphisms in Atopic Families: Implications for Modulated Allergen-Specific Immunoglobulin E and G1 Responses

Background: CD14 promoter DNA sequence polymorphisms for the endotoxin receptor gene have been implicated in modulating allergen-specific immunoglobulin (Ig)E responses in randomly selected individuals with atopy. We sought to determine if a single nucleotide polymorphism in the CD14 promoter region is associated with atopy in atopic families, and to assess its influence on serum levels of CD14 and allergen-specific IgE and IgG1 responses. Methods: We screened 367 members of 91 Caucasian nuclear families with a history of asthma for pulmonary function by spirometry, including methacholine challenge to detect bronchial hyperreactivity, and atopy by serum total IgE and skin prick test to 14 allergens. The CD14 promoter single nucleotide polymorphism was analyzed in DNA isolated from peripheral blood mononuclear cells to identify C/C, C/T and T/T genotypes. Serum tests were done for soluble CD14 (sCD14) and dust mite-specific antibody (Der p 1-IgG1). Results: Serum sCD14 levels were not associated with clinical phenotypes (asthma, bronchial hyperreactivity or atopy). However, sCD14 levels were inversely related to both allergen-specific IgE and Der p 1-IgG1 production, but only among those with evidence of atopic sensitization. Linear regression analysis, accounting for random family effects, demonstrated a higher production of allergen-specific IgE or Der p 1-IgG1 associated with the T/T genotype and a lower level of specific IgE and IgG1 production associated with sCD14 levels. Conclusions: An element of the innate immune system (CD14) has profound effects upon modulating the acquired allergen-specific immunoglobulin responses among those with an inherited atopic predisposition.

Gene expression of interleukin 18 in unstimulated peripheral blood mononuclear cells of patients with alcoholic cirrhosis

BACKGROUNDMost patients with alcohol induced cirrhosis (AC) and chronic endotoxinaemia are not suffering from clinically evident systemic inflammatory reactions. This may be due to altered gene expression of cytokines, possibly...

Serum levels of CD14 in neonatal sepsis by Gram-positive and Gram-negative bacteria.

The purpose of this study is to measure soluble CD14 (sCD14) levels in sera from newborn with sepsis, to compare it with other markers, and to study its evolution in Gram-negative and Gram-positive sepsis. Forty normal newborns were included (26 were full term and 14 were preterm infants), 20 babies had a positive blood culture (11 Gram-positive and 9 Gram-negative) and 16 cases were suspected of having sepsis based on clinical and laboratory findings, but a negative blood culture. Interleukin-6 (IL-6), sCD14, and tumour necrosis factor-alpha (TNF alpha) were measured by enzyme immunoassay, and fibronectin (FN) and C-reactive protein (CRP) by radial immunodiffusion. Neonates with a positive blood culture had increased levels of sCD14 (3.20 +/- 1.26 micrograms ml-1, p < 0.001), CRP (69 +/- 46 micrograms ml-1, p < 0.001) and IL-6 (134 +/- 150 pg ml-1, p < 0.001), and decreased values of FN (12.3 +/- 6.6 mg ml-1, p < 0.001). TNF alpha levels were also high (160 +/- 37 pg ml-1), but this increase was not statistically significant. Newborn infants suspected of having sepsis but a negative blood culture had similar but milder abnormalities. Soluble CD14 levels correlated with CRP values; however, there was no correlation between sCD14, TNF alpha and IL-6. Neonates with sepsis by Gram-positive bacteria had lower sCD14 levels than patients with Gram-negative sepsis (2.63 +/- 1.2 versus 4.04 +/- 1.0 micrograms ml-1, p < 0.05). In conclusion, the sCD14 level is increased in newborn infants with sepsis, and this is higher in infections by Gram-negative bacteria, suggesting a different contribution of monocyte and macrophage cells. In contrast, IL-6, TNF alpha, CRP and FN values are similar in infections by Gram-positive and Gram-negative bacteria.

IFN-alpha-mediated suppression of low-affinity FC(epsilon) receptors on Peyer's patch lymphocytes and augmentation of soluble CD23: implications for IgE responses.

The ability of interleukin (IL)-6 or interferon-alpha (IFN-alpha) to regulate expression of low-affinity Fc(epsilon) receptor (CD23) and serum levels of CD23 was studied in benzylpenicilloyl-keyhole limpet hemocyanin-sensitized BALB/c mice at the peak of a hapten-specific immunoglobulin E (IgE) antibody-forming cell (AFC) response. These responses are analogous to those observed in human atopic disease. To induce peak IgE responses, mice were injected intraperitoneally with BPO-KLH (10 micrograms) in aluminum hydroxide gel (alum) on days 0, 21, and 42. On day 44, mice were injected subcutaneously with IL-6 (100-1000 U) or IFN-alpha (1000-10,000 U). On day 46, numbers of CD23+ lymphocytes in Peyer's patches (PP), mesenteric lymph nodes (MLN), and spleen and levels of soluble CD23 in serum were determined (flow microfluorimetry and enzyme-linked immunosorbent assay, confirmed by competition assay). Data are expressed as percent total cells or as optical density at 490 nm. IFN-alpha treatment strongly suppressed (up to 100%) numbers of CD23+ cells exclusively in PP (i.e., numbers of CD23+ cells in MLN and spleen were unchanged) whereas serum levels of soluble CD23 were dramatically increased (60%). IL-6 treatment had no effect on either numbers of CD23+ lymphocytes or on serum levels of soluble CD23. The data suggest that the mechanism(s) by which IFN-alpha, but not IL-6, regulates IgE responses involves suppression of CD23 expression on lymphocytes in PPs and supports a central role for these organs in regulation of IgE responses in vivo.