Soluble CD14 receptor expression and monocyte heterogeneity but not the C-260T CD14 genotype are associated with severe acute pancreatitis

OBJECTIVE: Soluble CD14 is derived from a membrane glycoprotein, and it enhances endothelial cytokine responses to lipopolysaccharide. We studied the role of soluble CD14 in the pathogenesis of the systemic inflammatory response associated with acute pancreatitis, to determine whether altered expression was due to a functional C-260T polymorphism in the CD14 promoter gene or altered monocyte heterogeneity. DESIGN: Prospective case-matched study. SETTING: Tertiary pancreatic treatment unit in the United Kingdom. SUBJECTS: Patients with pancreatitis and controls. INTERVENTIONS: DNA from 117 patients with pancreatitis (34 severe) and 263 controls underwent CD14 genotyping using restriction fragment length polymorphism-polymerase chain reaction. MEASUREMENTS AND MAIN RESULTS: Peripheral venous blood samples at 24 and 72 hrs after the onset of abdominal pain were analyzed for sCD14 levels. Isolated peripheral blood mononuclear cells were phenotyped for CD14/CD16 receptor expression using immunofluorescence flow cytometry. Disease severity was assessed using Atlanta criteria, Acute Physiology Scores, and C-reactive protein.Soluble CD14 levels were higher in severe (24-hr median, 66.6 ng/mL; 72-hr median, 72.2 ng/mL) compared with mild attacks (24-hr median, 50.7 ng/mL; 72-hr median, 49.7 ng/mL, p < .001), although the latter was similar to controls (median, 51 ng/mL). Furthermore, soluble CD14 levels correlated with Acute Physiology Scores (p < .001) and C-reactive protein (p = .01).Peripheral blood mononuclear cells CD14++ (p = .008), CD14+/16+ (p = .003), and CD16++ (p = .015) receptor densities were all increased in severe attacks at 24 hrs. Early CD14+/16+ receptor density correlated with sCD14 (p < .001), Acute Physiology Scores (p < .001), and C-reactive protein (p = 0.006). The CD14 genotype prevalence in acute pancreatitis was similar to controls and failed to correlate with any variables studied. CONCLUSIONS: Increased soluble CD14 expression is associated with the systemic inflammatory response to acute pancreatitis and an expansion of the proinflammatory CD14+/CD16+ monocyte subset. Its targeted disruption may afford some benefit in preventing the development of systemic complications.     

Elevated plasmatic level of soluble IL-7 receptor is associated with increased mortality in septic shock patients

Purpose

Adjunctive immunoadjuvant therapies are now proposed in the treatment of septic patients that develop immune dysfunctions. However, a prerequisite is to identify patients at high risk of death that would benefit from such therapy. Knowing that rhIL-7 is a putative candidate for septic shock treatment, we evaluated the association between increased plasmatic level of soluble CD127 (sCD127, IL-7 receptor alpha chain) and mortality after septic shock.

Methods

sCD127 plasmatic level was measured in 70 septic shock patients sampled at day 1–2 (D1) and day 3–4 (D3) after the onset of shock and 41 healthy volunteers.

Results

Compared with survivors, non-survivors presented with significantly higher sCD127 concentrations at D1 and D3 (p < 0.001 and p = 0.002). At D1, the area under the receiver operating characteristic curve for sCD127 level association with mortality was 0.846 (p < 0.0001). Kaplan–Meier survival curves illustrated that mortality was significantly different after stratification based on D1 sCD127 level (log rank test, hazard ratio 9.10, p < 0.0001). This association was preserved in multivariate logistic regression analysis including clinical confounders (age, SAPS II and SOFA scores, odds ratio 12.71, p = 0.003). Importantly, patient stratification on both D1 sCD127 value and SAPS II score improved this predictive capacity (log rank test, p = 0.0001).

Conclusions

Increased sCD127 plasmatic level enables the identification of a group of septic shock patients at high risk of death. After confirmation in a larger cohort, this biomarker may be of interest for patient stratification in future clinical trials.     

Serum alanine aminotransferase is correlated with hematocrit in healthy human subjects

Abstract

Background. Serum alanine aminotransferase (ALT) activity is a widely-used surrogate marker for liver injury. However, mild elevation of serum ALT is frequently observed in apparently healthy individuals, making it sometimes challenging to interpret whether this laboratory abnormality is medically benign or serious. To obtain a better understanding of the factors influencing ALT levels, we examined the relation between ALT and a number of anthropometric and biochemistry measurements in humans. Methods. We assessed the associations of ALT with hematocrit (HCT) in 1,200 apparently healthy adults from an Amish population. Multivariate analyses were carried out to determine whether observed associations were independent of other factors known to modulate ALT and HCT, including body mass index (BMI) and sex. The correlation detected in the Amish was then replicated in an independent population sample (N = 9,842) from the National Health and Nutrition Examination Survey (NHANES) III. Results. ALT levels were positively correlated with HCT (r = 0.33, p < 0.0001) in both Amish and NHANES III. The magnitude of association was unchanged after adjustment for BMI, but was reduced by age/sex adjustment to r = 0.18 (p < 0.0001) and r = 0.17 (p < 0.0001) in the Amish and NHANES populations, respectively. HCT accounts for about 3% of the population variation in ALT, which is smaller than the contributions of gender and BMI, but larger than individual blood pressure and cholesterol components. Conclusions. We observed a correlation between ALT and HCT, suggesting that HCT may be a newly identified modulator of ALT in humans.     

Human monocyte CD163 expression inversely correlates with soluble CD163 plasma levels

BACKGROUND: CD163 is a monocyte/macrophage-restricted receptor involved in the clearance of hemoglobin-haptoglobin complexes and regulation of inflammatory processes. CD163 is shed from the cell surface and exists as a soluble form in plasma (sCD163). Monocyte CD163 and sCD163 are potential diagnostic tools in variety of disease states. METHODS: We determined the relation between plasma sCD163 levels by enzyme-linked immunosorbent assay, membrane expressions of CD163, CD64, and CD14 on blood monocytes by flow cytometry, and monocyte counts in 129 random blood samples. RESULTS: A strong inverse correlation was found between membrane CD163 expression and sCD163 levels (r = -0.65, P < 0.001). Monocyte CD163 expression and SCD163 levels did not correlate with the monocyte absolute count. CONCLUSIONS: The inverse relation between monocyte surface CD163 expression and sCD163 levels in human blood suggests that plasma sCD163 is derived from circulating monocytes, in addition to an unknown component from tissue macrophages. The lack of correlation with the absolute monocyte number suggests that such a balance is driven by the functional state of monocytes, rather than simply by numerical changes in circulating cells. We propose that further clinical evaluations of CD163 as a diagnostic parameter should include simultaneous measurements of soluble and cell-bound forms of this antigen.     

A functional promoter polymorphism in monocyte chemoattractant protein-1 is associated with increased susceptibility to pulmonary tuberculosis

We examined the distribution of single nucleotide polymorphisms (SNPs) in nitric oxide synthase 2A, monocyte chemoattractant protein-1 (MCP-1), regulated on activation, normal T cell expressed and secreted, and macrophage inflammatory protein-1alpha genes in tuberculosis patients and healthy controls from Mexico. The odds of developing tuberculosis were 2.3- and 5.4-fold higher in carriers of MCP-1 genotypes AG and GG than in homozygous AA. Cases of homozygous GG had the highest plasma levels of MCP-1 and the lowest plasma levels of IL-12p40, and these values were negatively correlated. Furthermore, stimulation of monocytes from healthy carriers of the genotype GG with Mycobacterium tuberculosis antigens yielded higher MCP-1 and lower IL-12p40 concentrations than parallel experiments with monocytes from homozygous AA. Addition of anti-MCP-1 increased IL-12p40 levels in cultures of M. tuberculosis-stimulated monocytes from homozygous GG, and addition of exogenous MCP-1 reduced IL-12p40 production by M. tuberculosis-stimulated monocytes from homozygous AA. Furthermore, we could replicate our results in Korean subjects, in whom the odds of developing tuberculosis were 2.8- and 6.9-fold higher in carriers of MCP-1 genotypes AG and GG than in homozygous AA. Our findings suggest that persons bearing the MCP-1 genotype GG produce high concentrations of MCP-1, which inhibits production of IL-12p40 in response to M. tuberculosis and increases the likelihood that M. tuberculosis infection will progress to active pulmonary tuberculosis.     

Asymptomatic alanine aminotransferase elevations with therapeutic doses of acetaminophen

While acetaminophen overdose has been recognized as a cause of alanine aminotransferase (ALT) elevations for over 40 years, recent studies have reported asymptomatic ALT elevations in research subjects who are administered with therapeutic doses (4 g/d or less) of acetaminophen for more than 4 days. While the clinical course of these elevations is not completely defined, available evidence suggests that even in high risk groups the elevations are not accompanied by evidence of hepatic dysfunction and that resolve if treatment is continued. Toxicologists should consider therapeutic acetaminophen use as a cause of ALT elevation. Further study of the mechanism of ALT elevations may provide new insight into other causes of drug-induced liver injury and hepatic adaptation.     

Source of increased serum aspartate and alanine aminotransferase: cycloheximide effect on carbon tetrachloride hepatotoxicity

Repeated doses of the protein synthesis inhibitor cycloheximide prevented the increases in rat liver mitochondrial and cytosolic aspartate aminotransferase, in alanine aminotransferase and in protein content observed 24 h after a single carbon tetrachloride injection. Serum aminotransferase activity increases induced by carbon tetrachloride were also decreased as much as 75.7% with cycloheximide. Increased synthesis is, therefore, suggested as an important and sometimes major source of increased serum aminotransferases in hepatocellular injury. This effect of cycloheximide lends support to the hypothesis that the liver enzyme increases after CCl4 are probably due to increased synthesis, in addition to the classically held mechanisms of leakage from necrotic or damaged hepatocytes. This explanation of the mechanisms of release of aminotransferases in rat liver injury would clarify many clinical observations if the same phenomenon were to occur in humans in response to hepatic injury. These data suggest that increased serum aminotransferase activities represent a healing, in addition to a degenerative, process.     

Asymptomatic alanine aminotransferase elevations with therapeutic doses of acetaminophen

While acetaminophen overdose has been recognized as a cause of alanine aminotransferase (ALT) elevations for over 40 years, recent studies have reported asymptomatic ALT elevations in research subjects who are administered with therapeutic doses (4 g/d or less) of acetaminophen for more than 4 days. While the clinical course of these elevations is not completely defined, available evidence suggests that even in high risk groups the elevations are not accompanied by evidence of hepatic dysfunction and that resolve if treatment is continued. Toxicologists should consider therapeutic acetaminophen use as a cause of ALT elevation. Further study of the mechanism of ALT elevations may provide new insight into other causes of drug-induced liver injury and hepatic adaptation.     

Circulating C-type natriuretic peptide is increased in orthotopic cardiac transplant recipients and associated with cardiac allograft vasculopathy

C-type natriuretic peptide (CNP) is a potent, endothelial-derived relaxant and growth-inhibitory factor. Accelerated vascular disease is an important cause of morbidity in cardiac transplant recipients, and endothelial dysfunction is now well recognized in patients with cardiovascular disease. CNP has not previously been investigated following cardiac transplantation. We therefore studied plasma levels of immunoreactive CNP in patients early and late after heart transplantation, compared with levels in healthy subjects. We measured CNP in extracted human plasma using an antibody against human CNP-(1-22). CNP levels were significantly elevated in 13 cardiac recipients 2 weeks post-transplant [2.64+/-0.26 pmol/l (mean+/-S.E.M.)] compared with those in the normal healthy subjects (0.62+/-0.04 pmol/l; n=20, P<0.001). Plasma levels of CNP were also significantly elevated in a second group of established cardiac transplant recipients (1.15+/-0.07 pmol/l; n=46) studied 1-13 years post-transplant when compared with the healthy subjects (P<0.001). In the group studied later after transplantation, CNP levels were significantly associated with systolic blood pressure (P<0.05) and were higher in patients with angiographic post-transplant coronary artery disease (P=0.032). In conclusion, these findings clearly demonstrate that CNP is elevated soon after cardiac transplantation and remains raised in patients even several years post-transplant. CNP may be important as a circulating or local hormone involved in vascular contractile function and in the pathophysiology of cardiac allograft vasculopathy following heart transplantation.     

Innate recognition of bacteria in human milk is mediated by a milk-derived highly expressed pattern recognition receptor, soluble CD14

Little is known about innate immunity to bacteria after birth in the hitherto sterile fetal intestine. Breast-feeding has long been associated with a lower incidence of gastrointestinal infections and inflammatory and allergic diseases. We found in human breast milk a 48-kD polypeptide, which we confirmed by mass spectrometry and sequencing to be a soluble form of the bacterial pattern recognition receptor CD14 (sCD14). Milk sCD14 (m-sCD14) concentrations were up to 20-fold higher than serum sCD14 from nonpregnant, pregnant, or lactating women. In contrast, lipopolysaccharide (LPS)-binding protein was at very low levels. Mammary epithelial cells produced 48-kD sCD14. m-sCD14 mediated activation by LPS and whole bacteria of CD14 negative cells, including intestinal epithelial cells, resulting in release of innate immune response molecules. m-sCD14 was undetectable in the infant formulas and commercial (cows') milk tested, although it was present in bovine colostrum. These findings indicate a sentinel role for sCD14 in human milk during bacterial colonization of the gut, and suggest that m-sCD14 may be involved in modulating local innate and adaptive immune responses, thus controlling homeostasis in the neonatal intestine.     

可溶性白细胞分化抗原14在脓毒症中的研究进展

脓毒症、严重脓毒症和脓毒症休克是急诊科经常处理的疾病,有很高的病死率,早期诊断是提高生存率的关键因素之一。近几年,降钙素原被用作诊断脓毒症患者的生物学标记物,尽管它与感染密切相关,但是特异性有限,在发生全身炎症反应综合征时会升高。可溶性白细胞分化抗原14(sCD14-st,又称presepsin)是一种存在于单核细胞/巨噬细胞中的糖蛋白。初步报道显示脓毒症患者体内的sCD14-st水平比健康者体内的sCD14-st显著升高。     

外周血单核细胞膜CD14表达预测脓毒症患者预后的研究

目的 通过对脓毒症患者外周血单核细胞膜CD14表达的动态观察,探讨CD14表达的动态监测在脓毒症预后预测中的作用.方法 对32例成人脓毒症患者外周血单核细胞膜CD14进行动态检测,并与20名健康志愿者进行对照.在脓毒症确诊后的第1天、第3天、第7天及第14天用流式细胞术进行外周血单核细胞膜CD14的检测,采用Cellquest软件分析有核细胞中CD14阳性率(CD14%),CD14平均荧光强度(CD14MFI),同时进行白细胞计数(WBC),并计算CD14指数(CD14IND,CD14%×CD14MFI×WBC).结果 有核细胞中CD14%,CD14MFI,CD14IND明显低于健康对照组.脓毒症患者中死亡组CD14%、CD14MFI、CD14IND均低于存活组.以CD14%≤1.20,CD14MFI≤35.94,CD14IND≤4.40作为脓毒症患者预后预测的临界值,其敏感性和特异性分别为80.0%和90.9%,90.0%和90.9%,90.0%和95.5%.结论 外周血单核细胞膜CD14的表达与脓毒症患者预后密切相关.动态监测CD14可预测脓毒症患者的预后.     

Circulating oxidized low-density lipoprotein is increased in hypertension

Oxidized low-density lipoprotein (OxLDL) and autoantibodies to OxLDL (aOxLDL) are implicated in the development of atherosclerosis. The objective of this study was to determine the importance of these factors in hypertension, a major risk factor for atherosclerosis. Samples were obtained from 111 men with established hypertension (diastolic pressure >95 mmHg) from the Swedish component of an ongoing hypertension study (European Lacidipine study on Atherosclerosis, ELSA) and from 75 normotensive control men, who were from a Swedish population-screening programme (diastolic pressure <80 mmHg). The presence of carotid atherosclerosis and the intima-media thicknesses were determined by ultrasonography. A monoclonal antibody to OxLDL, EO6, was used to determine oxidation epitopes in LDL. aOxLDL of IgG and IgM subclass were tested by ELISA against OxLDL. Hypertensive men had increased OxLDL levels compared with normotensives ( P =0.002), whereas autoantibodies tested were largely similar between groups. There was no association between the antibodies tested, or OxLDL and carotid atherosclerosis. Age was not associated with OxLDL or aOxLDL measurements. Taken together, our findings indicate that OxLDL is elevated in hypertensive men, which may predispose to atherosclerosis in hypertension. In contrast, aOxLDL levels were unchanged and the role of aOxLDL may depend on disease stage and/or type.     

脊髓半切伤大鼠血清谷丙转氨酶和谷草转氨酶活性变化的研究

目的:探讨大鼠血清谷丙转氨酶(ALT)和谷草转氨酶(AST)的活性变化与脊髓半切伤严重程度的关系。方法:测定30只大鼠脊髓半切伤急性期和恢复期血清中ALT和AST的水平以及10只对照组大鼠血清的ALT和AST的浓度。结果:脊髓半切伤大鼠急性期血清中ALT,AST活性分别为(51.01±11.08)和(56.08±20.12)nkat/L明显高于假手术组急性期活性犤(36.01±8.79),(30.57±12.98)nkat/L,t=1.32,0.56,P<0.01犦。脊髓半切伤大鼠急性期比恢复期血清中ALT和AST活性犤48.05±18.06),(51.09±11.08)nkat/L犦明显升高。结论:ALT,AST在脊髓半切伤急性期呈反应性升高,与脊髓损伤严重程度呈正相关。     

脑梗塞患者血清可溶性CD14水平的初步观察

目的　通过检测脑梗塞患者血清可溶性CD14 (sCD14 )水平,研究缺血性脑血管病患者外周血单核细胞的活化状态。方法　收集脑梗塞患者和正常人血清,用单多抗双夹心ELISA法检测血清sCD14含量并进行统计分析。结果　脑梗塞患者血清sCD14水平较同年龄正常人显著升高(P <0. 0 0 1) ,其中感染组、未感染组血清sCD14含量较正常人均显著升高(P值分别为0 .0 0 1和0 . 0 11) ;而感染组与未感染组之间血清sCD14含量无显著性差异(P =0 .175 ) ;血清sCD14含量与白细胞数无显著相关性(P =0. 17)。结论　脑梗塞患者血清sCD14水平升高,提示其外周血单核细胞处于活化状态,但与是否存在感染无明显相关性。     

冠心病患者sCD14血清水平检测的临床意义

目的探讨血清可溶性CD14(sCD14)水平在监测冠心病病情及其与冠状动脉病变程度的关系。方法168例冠心病患者,按临床诊断分为三组:急性心肌梗死(AMI)60例、不稳定型心绞痛(UAP)58例、稳定型心绞痛(SAP)50例和对照组55例。用酶联免疫吸附试验检测各组血清sCD14的水平,并比较各组间的差异。对冠心病患者的外周血白细胞总数变化及其与血清sCD14水平进行直线相关分析。结果AMI组、UAP组及SAP组的血清sCD14水平比对照组高(P＜0．05);AMI组、UAP组sCD14水平和SAP组相比,其值增加明显;AMI组和UAP组结果相似;冠心病患者sCD14水平与外周血白细胞总数变化呈正相关。结论sCD14可能是冠状动脉粥样硬化的标志,参与了冠心病的发病过程,其值与冠状动脉病变程度密切相关。