Leucocyte activation markers in clinical practice

Short-Term Effects of a New Bicarbonate/Lactate-Buffered and Conventional Peritoneal Dialysis Fluid on Peritoneal and Systemic Inflammation in CAPD Patients: A Randomized Controlled Study

Objectives

This study was designed to compare the local peritoneal and systemic inflammatory effects of a conventional lactate-based (Lac) peritoneal dialysis (PD) solution and a new biocompatible bicarbonate/lactate-based (Bic/ Lac) solution having low concentration of glucose degradation products.

Methods

26 stable, prevalent PD patients were enrolled in this prospective study. They sequentially underwent 3 months of therapy with the Lac solution and 3 months with the Bic/Lac solution in a randomized order. Flow cytometry was used to measure the expression of inflammatory molecules on peritoneal cells in overnight effluent collected at the end of each study period.

Results

21 patients successfully completed the study. Mean fluorescence intensity of human leukocyte antigen (HLA)-DR and CD14 expression by macrophages were not different between Lac and Bic/Lac. The peritoneal appearance rate of cancer antigen 125 (kU/minute) was 68 ± 37 with Lac and 133 ± 66 with Bic/Lac ( p < 0.001), and of interleukin (IL)-6 (ng/minute), 0.28 ± 0.2 with Lac and 0.18 ± 0.16 with Bic/Lac ( p = 0.014). HLA-DR macrophage expression and IL-6 peritoneal appearance rates did not correlate. Serum concentrations with Lac and Bic/Lac were, for IL-6, 3.49 ± 2.28 and 3.72 ± 2.46 ng/L ( p = 0.17), and for high-sensitivity C-reactive protein, 2.31 ± 2.98 and 2.71 ± 3.31 mg/L ( p = 0.32) respectively. The concentration of effluent macrophages (x106/L) with Lac was 1.6 ± 1.6 and with Bic/Lac 2.6 ± 3.3 ( p = 0.07).

Conclusions

We conclude that, although there was a significant reduction in peritoneal IL-6 in patients using Bic/ Lac solution, systemic levels of inflammatory markers did not differ between the two solutions and no changes were present in macrophage surface activation markers, suggesting perhaps a less important role of peritoneal macrophages in the intraperitoneal chronic inflammatory process. The number of effluent macrophages tended to be higher in patients using the Bic/Lac solution, possibly contributing to improved intraperitoneal defense.

The role of interleukin-18 in pancreatitis and pancreatic cancer

Originally described as an interferon (IFN)-γ-inducing factor, interleukin (IL)-18 has been reported to be involved in Th1 and Th2 immune responses, as well as in activation of NK cells and macrophages. There is convincing evidence that IL-18 plays an important role in various pathologies (i.e. inflammatory diseases, cancer, chronic obstructive pulmonary disease, Crohn's disease and others). Recently, IL-18 has also been shown to execute specific effects in pancreatic diseases, including acute and chronic pancreatitis, as well as pancreatic cancer. The aim of this study was to give a profound review of recent data on the role of IL-18 and its potential as a therapeutic target in pancreatic diseases. The existing data on this topic are in part controversial and will be discussed in detail. Future studies should aim to confirm and clarify the role of IL-18 in pancreatic diseases and unravel their molecular mechanisms.

Neutrophils as a Source of Chitinases and Chitinase-Like Proteins in Type 2 Diabetes

PURPOSE

The pathophysiological role of human chitinases and chitinase-like proteins (CLPs) is not fully understood. We aimed to determine the levels of neutrophil-derived chitotriosidase (CHIT1), acidic mammalian chitinase (AMCase) and chitinase 3-like protein 1 (YKL-40) in patients with type 2 diabetes (T2D) and verify their association with metabolic and clinical conditions of these patients.

METHODS

Neutrophils were obtained from the whole blood by gradient density centrifugation from 94 T2D patients and 40 control subjects. The activities of CHIT1 and AMCase as well as leukocyte elastase (LE) were measured fluorometrically and concentration of YKL-40 immunoenzymatically. Also, routine laboratory parameters in serum/plasma were determined by standard methods.

RESULTS

The levels of all three examined proteins were about 2-times higher in diabetic patients in comparison to control subjects. They were significantly correlated with the activity of LE and increased progressively across tertiles of LE activity. Moreover, the activities of CHIT1 and AMCase were significantly correlated with each other. Metabolic compensation of diabetes did not influence the levels of these proteins. In the subgroup of patients with inflammatory evidence only YKL-40 concentration was significantly higher compared to those without inflammation. The highest levels of all three proteins were observed in patients with macroangiopathies. Insulin therapy was associated with lower levels of examined proteins.

CONCLUSIONS

We revealed that neutrophils may be an important source of the increased levels of chitinases and CLPs in T2D, and these proteins may participate in inflammatory mechanisms in the course of the disease and consequent development of diabetic angiopathies.

Flow cytometric assessment of monocyte activation markers and circulating endothelial cells in patients with localized or metastatic breast cancer

BACKGROUND

Monocyte activation in cancer patients may be reflective of anticancer activity. However, studies indicate that recruitment of macrophages can actually promote tumor growth and angiogenesis. Assessment of other microenvironmental cells such as circulating endothelial cells (CECs) may provide additional information regarding disease progression. The objective of this study was to assess monocyte activation and CECs in breast cancer patients and determine the potential clinical relevance during disease progression.

METHODS

Patients (n = 41) with localized or metastatic breast cancer who were not currently receiving treatment were eligible for study inclusion. Peripheral blood was collected and analyzed by flow cytometry for monocyte activation (Leuko64 assay kit), and for CECs (CD146(+)CD45(-) phenotype).

RESULTS

Metastatic breast cancer patients demonstrated a higher monocyte CD64 index relative to normal donors and localized breast cancer patients (P < 0.05). Furthermore, breast cancer patients had a lower monocyte CD163 index relative to normal donors (P = 0.008). Localized breast cancer patients demonstrated higher levels of CD146(+)CD45(-) cells CECs relative to metastatic breast cancer patients and normal donors. Within the localized breast cancer population, levels of CD146(+)CD45(-) cells increased with disease stage (P < 0.05).

CONCLUSIONS

These results suggest that monocyte activation and CECs may play a role in breast cancer progression. We speculate that monocyte activation may reflect a reaction to metastatic cells and/or response to tissue damage caused by metastatic growth in distant organs. Furthermore, the observation that CECs increase with disease stage in localized breast cancer suggests that CECs could be a useful surrogate marker for disease progression in this patient population.

Modeling effect of the septic condition and trauma on C-reactive protein levels in children with sepsis: a retrospective study

Introduction

Sepsis is the main cause of morbidity and mortality in intensive care units and its early diagnosis is not straightforward. Many studies have evaluated the usefulness of various markers of infection, including C-reactive protein (CRP), which is the most accessible and widely used. CRP is of weak diagnostic value because of its low specificity; a better understanding of patterns of CRP levels associated with a particular form of infection may improve its usefulness as a sepsis marker. In the present article, we apply multilevel modeling techniques and mixed linear models to CRP-related data to assess the time course of CRP blood levels in association with clinical outcome in children with different septic conditions.

Methods

We performed a retrospective analysis of 99 patients with systemic inflammatory response syndrome, sepsis, or septic shock who were admitted to the Pediatric Critical Care Unit at the University Hospital, Brno. CRP blood levels were monitored for 10 days following the onset of the septic condition. The effect of different septic conditions and of the surgical or nonsurgical diagnosis on CRP blood levels was statistically analyzed using mixed linear models with a multilevel modeling approach.

Results

A significant effect of septic condition and diagnosis on the course of CRP levels was identified. In patients who did not progress to septic shock, CRP blood levels decreased rapidly after reaching peak values – in contrast to the values in patients with septic shock in whom CRP protein levels decreased slowly. Moreover, CRP levels in patients with a surgical diagnosis were higher than in patients with a nonsurgical condition. The magnitude of this additional elevation in surgical patients did not depend on the septic condition.

Conclusion

Understanding the pattern of change in levels of CRP associated with a particular condition may improve its diagnostic and prognostic value in children with sepsis.

Isolated head injury in children affects the neutrophil function and lymphocyte count

BACKGROUND

Outcomes of treatment of postinjury complications remain unsatisfactory and research continues into the impact of trauma on innate and acquired immunity. The aim of our study was to describe how head injury affects a child's immunity by measuring the neutrophil function and lymphocytes subsets.

METHODS

The peripheral blood of 16 children with head trauma (Glasgow Coma Score < or =9) was examined. The blood samples were collected on the first and on the seventh day after trauma. The production of reactive oxygen species (ROS), spontaneous and stimulated, the expression of CD11b, and the lymphocyte subpopulations were measured. The blood of healthy children was studied as control. The impact of endotracheal intubation on the examined parameters was analyzed as well.

RESULTS

Head trauma leads to the increase of leukocytosis; the total production of ROS by peripheral blood neutrophils does not change after head injury. Correction of the results according to the number of neutrophils revealed a significant decrease in ROS production by a single neutrophil. The expression of adhesion molecule CD11b did not change. Head injury in children causes the decrease of the total lymphocyte count, CD3, CD4, CD8, and natural killer cells count on both the first and the seventh postinjury day. On the seventh day the significant decrease of natural killer cells subset was observed. The CD4/CD8 ratio increased from 1.5 (the first day) to 2.5 (the seventh day). The intubation did not affect the examined parameters.

CONCLUSIONS

After head injury, total ROS production and adhesion molecule CD11b expression remained unchanged when compared with control. The study did not demonstrate evidence for neutrophil activation in patients with head injuries. The total lymphocyte count was found to be decreased and the composition of lymphocytes' subsets was deeply impaired.

Sustained activation of neutrophils in the course of Kawasaki disease: an association with matrix metalloproteinases

Kawasaki disease (KD) is an acute febrile syndrome of childhood, characterized by vasculitis of the medium-sized arteries. White blood cell counts and the inflammatory parameter C-reactive protein (CRP) are known to be elevated in the acute phase of the disease. In this study we investigated the course of inflammatory cell type-specific parameters in KD over a longer period of time. Plasma levels of human neutrophil elastase (HNE), matrix metalloproteinases-2 and -9 (MMP2, MMP9), and neutrophil gelatinase-associated lipocalin (NGAL), macrophage neopterin and CRP were measured. Plasma samples were collected in the acute, subacute and early convalescent stage, and three months after the onset of disease. Median CRP and neopterin normalized within two weeks. In contrast, six weeks and three months after onset of disease, levels of HNE were still elevated, with median values of 163 ng/ml and 156 ng/ml, respectively (control children median < 50 ng/ml; for all time-points P < 0.0001). Values of NGAL correlated with the levels of HNE (r = 0.39, P = 0.013). These results demonstrate a longer state of neutrophil activation in KD than was previously assumed. The potential relationship between this prolonged neutrophil activation, coronary artery lesion formation and their persistence, as well as the risk of premature atherosclerosis warrants further evaluation.

Balance of pro- and anti-inflammatory cytokines in liver surgery

Inflammatory response in surgery is associated with the release of cytokines. Many cytokines are produced by macrophages; therefore surgical injuries to the liver may have great influence on the release of cytokines. Ischemia creates tissue injury and may contribute to the cytokine release. A balanced ratio of pro- and anti-inflammatory cytokines is important for appropriate immune response; excessive inflammation or hypo-responsiveness can lead to post-operative complications. To determine the magnitude of the cytokine response caused by liver surgery and to evaluate the balance of pro- and anti-inflammatory cytokines released during the operation, we measured levels of tumor necrosis factor-alpha (TNFalpha), interleukin (IL)-1beta, IL-6 and IL-10 in 19 patients undergoing liver resection. The results showed a continuous rise of IL-6 and a transient elevation of IL-10. Levels of TNFalpha remained low; IL-1beta was not detected at any sampling time. We conclude that liver surgery induces cytokine response characterized predominantly by an early appearance of IL-6 and IL-10, the elevation of IL-6 may be mainly caused by splanchnic ischemia. The IL-6/IL-10 ratio could possibly reflect the balance of pro- and anti-inflammatory cytokines in liver surgery better than the TNFalpha/IL-10 ratio, which can well represent inflammatory status in sepsis.

Serum profiles of E-selectin, interleukin-10, and interleukin-6 and oxidative stress parameters in patients with acute pancreatitis and nonpancreatic acute abdominal pain

INTRODUCTION

Excessive inflammatory response is one of the major causes of early mortality in acute pancreatitis (AP).

AIM

To evaluate the serum profiles of E-selectin, interleukin (IL)-6, and IL-10 along with their correlation to the markers of oxidative stress and neutrophil activation in patients with AP and patients with nonpancreatic acute abdominal pain (NPAAP).

METHODOLOGY

This prospective clinical study included 56 patients with AP (28 with mild AP and 28 with severe AP) as well as 15 patients with NPAAP.

RESULTS

Serum concentrations of E-selectin, IL-10, and IL-6 and plasma concentrations of polymorphonuclear leukocyte elastase (determined on days 1-3, 5, and 10 after admission) were the highest in severe AP during the first 3 days and then declined. At day 10, the E-selectin level in severe AP was still higher than that in mild AP, and the IL-10 concentration increased again. There was no elevation in the E-selectin concentration in NPAAP patients, and IL-10 levels remained unchanged in mild AP. Oxidative stress, measured by serum malondialdehyde and 4-hydroxyalkenals levels, was the most pronounced in severe AP.

CONCLUSIONS

The serum E-selectin concentration is markedly elevated in severe AP and is less in mild AP but not in NPAAP. It may result from stimulation with different inflammatory mediators or indicate vascular endothelium injury mediated by oxidative stress, especially in the severe form of AP.

Human vs machine: evaluation of fluorescence micrographs

To enable high-throughput screening of molecular phenotypes, multi-parameter fluorescence microscopy is applied. Object of our study is lymphocytes which invade human tissue. One important basis for our collaborative project is the development of methods for automatic and accurate evaluation of fluorescence micrographs. As a part of this, we focus on the question of how to measure the accuracy of microscope image interpretation, by human experts or a computer system. Following standard practice we use methods motivated by receiver operator characteristics to discuss the accuracies of human experts and of neural network-based algorithms. For images of good quality the algorithms achieve the accuracy of the medium-skilled experts. In images with increased noise, the classifiers are outperformed by some of the experts. Furthermore, the neural network-based cell detection is much faster than the human experts.

A human model of platelet-leucocyte adhesive interactions during controlled ischaemia in patients with peripheral vascular disease

AIMS

In humans, little is known about the effects of platelet-leucocyte interactions on blood viscosity and microvascular perfusion. This study tested the hypotheses that (1) activation and interactions between platelets and leucocytes may have an impact on microvascular blood viscosity and perfusion in patients with stage II peripheral arterial occlusive disease, and (2) a powerful antiplatelet drug such as Clopidogrel might help to improve microvascular perfusion by reducing platelet-leucocyte activation and blood viscosity.

METHODS

Plasma concentrations of certain markers of leucocyte and platelet activation, in addition to low and high shear rate blood viscosity, were measured before and after a repeated exercise treadmill test. Functional parameters including maximum walking time, transcutaneous oxygen pressure, and half recovery time were also measured.

RESULTS

Blocking platelet activation only with a single dose of Clopidogrel (300 mg) did not improve microvascular blood viscosity and perfusion after repeated exercise, but a significant improvement in microvascular perfusion during controlled ischaemia and a lack of post exercise increase in low shear rate blood viscosity was achieved when both platelet and leucocyte activation were suppressed by a relatively longer treatment with Clopidogrel (four days).

CONCLUSIONS

Clopidogrel, by inhibiting platelet activation and aggregation, might also block the vicious cycle of leucocyte-platelet activation, thus improving the functioning of the microcirculation.

Azithromycin modulates neutrophil function and circulating inflammatory mediators in healthy human subjects

Effects on human neutrophils and circulating inflammatory mediators were studied in 12 volunteers who received azithromycin (500 mg/day, p.o.) for 3 days. Blood was taken 1 h before treatment, 2.5, 24 h and 28 days after the last dose. An initial neutrophil degranulating effect of azithromycin was reflected in rapid decreases in azurophilic granule enzyme activities in cells and corresponding increases in serum. The oxidative response to a particulate stimulus was also acutely enhanced. These actions were associated with high plasma and neutrophil drug concentrations. A continuous fall in chemokine and interleukin-6 serum concentrations, within the non-pathological range, accompanied a delayed down-regulation of the oxidative burst and an increase in apoptosis of neutrophils up to 28 days after the last azithromycin dose. Neutrophils isolated from blood at this time point still contained detectable drug concentrations. Acute neutrophil stimulation could facilitate antibacterial effects of azithromycin, while delayed, potentially anti-inflammatory activity may curtail deleterious inflammation.

Urinary bikunin determination provides insight into proteinase/proteinase inhibitor imbalance in patients with inflammatory diseases

Bikunin (BK) is a Kunitz-type proteinase inhibitor responsible for most of the antitryptic activity of urine and so is known as the urinary trypsin inhibitor. As its excretion increases in inflammatory conditions, it is often considered to be a positive acute phase protein (APP). However, the gene for BK is downregulated in inflammation. In human plasma the major part of BK is covalently linked through a glycosaminoglycan chain to one or two homologous peptide heavy chains, thus forming high molecular weight proteinase inhibitors called pre-alpha-inhibitor (PalphaI) and inter-alpha-inhibitor (IalphaI), respectively. The C-terminal parts of these heavy chains are very sensitive to proteolysis. Neutrophil proteinases in particular are able to release from IalphaI and PalphaI BK (M, about 25,000) which retains its antitryptic activity and is quickly excreted in urine. It was therefore an early supposition that the higher urinary excretion of BK occurring during inflammatory diseases should be, at least in some respect, related to a partial proteolysis of IalphaI and PalphaI. In this study we observed that BK, determined as antitryptic activity, was clearly increased in urine from 35 patients with inflammatory diseases varying in origin and severity (76.5 +/- 75.5 IU/g vs. reference value <10 IU/g creatinine). This increase seems mainly to be associated with polymorphonuclear leukocyte activation, monitored by human leukocyte elastase (HLE) determination rather than with the acute phase response assessed by C-reactive protein (CRP) measurement. For all the patients we found that the urinary levels of BK and serum concentration of intact IalphaI correlated inversely (r=-0.36; p=0.03), in agreement with the presumed precursor-product relationship linking IalphaI and BK. We also proved that urinary BK was significantly higher, and serum IalphaI was significantly lower, in samples with plasma HLE values above the reference: 90 microg/l. Taken together, our results demonstrate that BK, the urinary excretion of which is increased in inflammatory conditions, originates, at least partly, from IalphaI and PalphaI by proteolytic cleavage. Consequently, urinary BK determination provides information on the severity of systemic proteolysis occurring in inflammation. We also demonstrated that during inflammatory diseases IalphaI and PalphaI concentrations in serum are dependent on their increased utilization as well as on the regulation of their biosynthesis.

A neural classifier enabling high-throughput topological analysis of lymphocytes in tissue sections

A neural cell detection system (NCDS) for the automatic quantitation of fluorescent lymphocytes in tissue sections is presented in this paper. The system acquires visual knowledge from a set of training cell-image patches selected by a user. The trained system evaluates an image in 2 min calculating: the number, the positions, and the phenotypes of the fluorescent cells. For validation, the NCDS learning performance was tested by cross validation on digitized images of tissue sections obtained from inherently different types of tissue: diagnostic tissue sections across the human tonsil and across an inflammatory lymphocyte infiltrate of the human skeletal muscle. The NCDS detection results were compared with detection results from biomedical experts and were visually evaluated by our most experienced biomedical expert. Although the micrographs were noisy and the fluorescent cells varied in shape and size, the NCDS detected a minimum of 95% of the cells. In contrast, the cellular counts based on visual cell recognition of the experts were inconsistent and largely unreproducible for approximately 80% of the lymphocytes present in a visual field. The data indicate that the NCDS is rapid and delivers highly reproducible results and, therefore, enables high-throughput topological screening of lymphocytes in many types of tissue, e.g., as obtained by routine diagnostic biopsy procedures. High-throughput screening with the NCDS provides the platform for the quantitative analysis of the interrelationship between tissue environment, cellular phenotype, and cellular topology.

Concentration of leukocyte elastase in plasma and polymorphonuclear neutrophil extracts in type 2 diabetes

The concentration of leukocyte elastase/alpha1-proteinase inhibitor complexes in plasma and polymorphonuclear neutrophil extracts, and plasma trypsin inhibitory capacity were determined in 88 patients with type 2 diabetes and 47 control subjects. Higher values of these variables were found in patients as compared to controls (p < 0.001). The concentration of elastase was higher in obese patients than in lean ones (p < 0.05 for plasma, p < 0.01 for polymorphonuclear leukocytes). Only leukocyte elastase levels were significantly higher in the group with both micro- and macroangiopathy in comparison to the group with microangiopathy (p < 0.01) or macroangiopathy (p < 0.05) alone. Poor short-term glycaemic control was associated with higher elastase concentration in plasma and neutrophils (p < 0.05). The present study demonstrates that measurements of plasma polymorphonuclear neutrophil elastase level can be considered as a marker of development of diabetic angiopathy.