Neutrophils In Children Research Articles

Features of the neutrophil granulocyte phenotype in children with infectious mononucleosis

The course of infectious diseases caused by viruses, and their common outcome is determined by the activity of the inflammatory reaction which occurs both at the local and systemic levels. However, the features of neutrophil functions during inflammatory reaction are virtually unknown in the patients with infectious mononucleosis (IM), caused by Epstein–Barr virus (EBV). Hence, the aim of our study was to evaluate some characteristics of phenotypic spectrum of blood neutrophils in children with IM. Patients and methods. We examined 84 children aged 3 to 11 years with EBV infection with moderate or severe clinical course of the disease. All patients exhibited a positive test for EBV DNA in blood lymphocytes and appropriate serological markers of acute EBV infection. The control group consisted of 40 conditionally healthy children at the similar age range. The study of neutrophil phenotype was carried out by flow cytometry using direct immunofluorescence of whole peripheral blood samples. A study of the neutrophil phenotype with a combination of two functional antigens (CD64 and CD32) has revealed that in children with IM, regardless of age, the main fraction of blood neutrophils are double-negative cells, whereas in healthy children it consists of CD64-CD32+ neutrophils. The main fraction of neutrophils in the paired combination of CD64 and CD11b antigens in sick children aged 3-6 and 7-11 years was similar to the healthy controls (CD64-CD11b+), but with a change in the content of minor cell fractions. The number of CD64-CD15+ neutrophils (main fraction of cells in healthy children) proved to be significantly reduced in the IM patients of both age groups. However, we have revealed a marked increase in the level of double-negative cells for the CD64 and CD15 antigens. At the same time, the content of double-negative neutrophils for these markers was also increased in IM children of both age groups. The cells with CD11b-CD15+ and CD11b+CD15+ phenotypes comprised the main fractions in IM, as studied by a paired combination of CD11b and CD15 antigens; in healthy children – only CD11b+CD15+ neutrophils are detected. The phenotypic changes of neutrophils during IM suggest a decreased migratory ability of cells with high activity of proinflammatory functions. The established ontogenetic features of the neutrophil phenotype are significantly changed in the children with IM, probably, due to specific immunopathogenesis of the viral infection. The detected changes in phenotypic composition of neutrophils associated with IM may be caused both by the features of protective reaction of innate immune cells and pathogenic effects of the virus itself upon blood neutrophils.

Age-related changes in the parameters of cellular immunity, the activity of intracellular lymphocyte dehydrogenases and functional activity of neutrophils in children with Gaucher disease

Age-related changes in the parameters of cellular immunity, the activity of intracellular lymphocyte dehydrogenases and functional activity of neutrophils in children with Gaucher disease

ВОЗРАСТНЫЕ ОСОБЕННОСТИ ФОРМИРОВАНИЯ ВНЕКЛЕТОЧНЫХ ЛОВУШЕК НЕЙТРОФИЛОВ У ЗДОРОВЫХ ЛИЦ И БОЛЬНЫХ ТУБЕРКУЛЁЗОМ

Abstracts. Introduction. Forming a neutrophil extracellular trap (NET) from DNA (NETosis) is considered as a potentially significant marker in the diagnosis of tuberculosis. However, there is practically a lack of data regarding the age-related differences in forming extracellular traps in research publications. Aim. To determine the age-related differences of NETosis in healthy individuals and in tuberculosis (TB) patients. Materials and Methods. The ability of neutrophils to form extracellular traps was investigated in 4 groups: 1) 4-7-year-old children diagnosed with the primary tuberculosis complex, who fell ill within Omsk region; 2) healthy and uninfected children at the same age; 3) adults with tuberculosis, and 4) adults without tuberculosis. For this purpose, isolated fractions of neutrophils from peripheral blood of the groups under research were stimulated with a mixture of bacteria (probiotic) for 30 minutes. In the hanging-drop preparation, we analyzed the proportion of neutrophil extracellular traps and cells in the state of various motility degrees. Results and Discussion. Age-related differences in the ability of neutrophils to form extracellular traps were characterized by a more pronounced response of neutrophils to the NETosis stimulant in children in the control group in comparison with neutrophils isolated from blood in the group of healthy adult volunteers: Neutrophils of children (Me=16.1; Q1=12.8; Q3=18.3) were statistically significantly more intense (p=0.0002) than those of adults (Me=8.6; Q1=7.1; Q3=10.5) and formed filamentous NETs. In the groups of pediatric and adult pulmonary TB patients, the response of neutrophils to the NETosis stimulant was diametrically opposite. Neutrophils of children with primary tuberculosis complex, as of those in the control group, predominantly formed filamentous NETs, but in greater amounts, while neutrophils of adults with infiltrative or focal form and with at most 2 segments involved mainly formed cloudy NETs, whereas filamentous NETs prevailed for the adults in the control group after stimulation. At the same time, proportion of cloudy NETs did not exceed 5% in healthy children and healthy adults. Comparing the findings of our study with literature data, we hypothesized that, most likely, there is a greater increase in PAD4 expression and more pronounced histone H3 citrullination in children’s neutrophils than in those of adults. Conclusions. Our findings indicate more pronounced ex vivo processes induced by NETosis stimulator in both groups of children (healthy individuals and TB patients) as compared to adults in the respective groups, which should be considered by the researchers interpreting the findings of the ability of neutrophils to form extracellular traps in tuberculosis.

Dysfunctions of Neutrophils in the Peripheral Blood of Children with Cystic Fibrosis.

Dysfunction of neutrophils in patients with cystic fibrosis (CF) is best characterized in bronchoalveolar lavage (BAL), whereas peripheral blood neutrophils are less examined, and the results are contradictory, especially in younger populations. Therefore, this work aimed to study functional and phenotypic changes in circulating neutrophils in children with CF. The study included 19 CF children (5-17 years) and 14 corresponding age-matched healthy children. Isolated neutrophils were cultured either alone or with different stimuli. Several functions were studied: apoptosis, NET-osis, phagocytosis, and production of reactive oxygen species (ROS), neutrophil elastase (NE), and 11 cytokines. In addition, the expression of 20 molecules involved in different functions of neutrophils was evaluated by using flow cytometry. CF neutrophils showed reduced apoptosis and lower production of NE and IL-18 compared to the healthy controls, whereas IL-8 was augmented. All of these functions were further potentiated after neutrophil stimulation, which included higher ROS production and the up-regulation of CD11b and IL-10 expression. NET-osis was higher only when neutrophils from moderate-severe CF were treated with Pseudomonas aeruginosa, and the process correlated with forced expiratory volume in the first second (FEV1). Phagocytosis was not significantly changed. In conclusion, circulating neutrophils from children with CF showed fewer impaired changes in phenotype than in function. Functional abnormalities, which were already present at the baseline levels in neutrophils, depended on the type of stimuli that mimicked different activation states of these cells at the site of infection.

DNA Hypomethylation Is Associated with Increased Inflammation in Peripheral Blood Neutrophils of Children with Autism Spectrum Disorder: Understanding the Role of Ubiquitous Pollutant Di(2-ethylhexyl) Phthalate.

Autism spectrum disorder (ASD) is a multidimensional disorder in which environmental, immune, and genetic factors act in concert to play a crucial role. ASD is characterized by social interaction/communication impairments and stereotypical behavioral patterns. Epigenetic modifications are known to regulate genetic expression through various mechanisms. One such mechanism is DNA methylation, which is regulated by DNA methyltransferases (DNMTs). DNMT transfers methyl groups onto the fifth carbon atom of the cytosine nucleotide, thus converting it into 5-methylcytosine (5mC) in the promoter region of the DNA. Disruptions in methylation patterns of DNA are usually associated with modulation of genetic expression. Environmental pollutants such as the plasticizer Di(2-ethylhexyl) phthalate (DEHP) have been reported to affect epigenetic mechanisms; however, whether DEHP modulates DNMT1 expression, DNA methylation, and inflammatory mediators in the neutrophils of ASD subjects has not previously been investigated. Hence, this investigation focused on the role of DNMT1 and overall DNA methylation in relation to inflammatory mediators (CCR2, MCP-1) in the neutrophils of children with ASD and typically developing healthy children (TDC). Further, the effect of DEHP on overall DNA methylation, DNMT1, CCR2, and MCP-1 in the neutrophils was explored. Our results show that the neutrophils of ASD subjects have diminished DNMT1 expression, which is associated with hypomethylation of DNA and increased inflammatory mediators such as CCR2 and MCP-1. DEHP further causes downregulation of DNMT1 expression in the neutrophils of ASD subjects, probably through oxidative inflammation, as antioxidant treatment led to reversal of a DEHP-induced reduction in DNMT1. These data highlight the importance of the environmental pollutant DEHP in the modification of epigenetic machinery such as DNA methylation in the neutrophils of ASD subjects.

Нетозобразующая способность нейтрофилов у детей с латентной туберкулезной инфекцией при положительной пробе с аллергеном туберкулезным рекомбинантным

Publications on the role of neutrophils in tuberculosis are contradictory. The potentially versatile role of neutrophils in the pathogenesis of tuberculosis confirms that the participation of granulocytes in tuberculosis infection is important. Patients and methods. The prospective single-center study included 24 patients with latent tuberculosis infection at the time of the first positive test for the tuberculosis recombinant allergen in the absence of radiological changes and 29 children who made up the control group according to the results of the annual tuberculin diagnostics, with a negative reaction to the tuberculosis allergen with 2TE. In the formed groups, the netosis-forming ability of an isolated fraction of neutrophils of peripheral venous blood was determined in vitro using an original technique developed by members of the author's team Results. Neutrophils of children in the study groups demonstrated different levels of netosis-forming ability, and in the group with latent tuberculosis infection, the non-forming ability of neutrophils was higher in comparison with the control group. Neutrophils of both groups formed mainly filamentous traps. In the preparation of a group of children with latent tuberculosis infection, after stimulation of granulocytes with a probiotic, there was a decrease (p = 0.0011) in the percentage of hypoactivated neutrophils relative to the control group. Conclusions. Changes in the proinflammatory and antimicrobial properties of neutrophils can become one of the markers that allow us to assess the dynamics of localization of tuberculosis. Key words: children, latent tuberculosis infection, neutrophil extracellular traps, neutrophil non-forming ability, tuberculosis

Dysregulated Nrf2 signaling in response to di(2-ethylhexyl) phthalate in neutrophils of children with autism

Autism spectrum disorder (ASD) is characterized by constellation of impaired behaviors that include deficits in social interaction/communication and the presence of restricted/repetitive behavioral patterns. Both genetic component and environmental factors are thought to play a key role in the initiation and progression of ASD. Several environmental factors such as heavy metals and plasticizers are known to affect the progression of ASD. One of the most common pollutants in the environment today is di-2-ethylhexyl phthalate (DEHP). DEHP is utilized as a plasticizer in several household and office materials which range from medical devices to plastic toys. Children usually get exposed to DEHP at an early age through use of plastic toys and other plastic materials. Nuclear factor erythroid 2 (NFE2)-relatedfactor-2 (Nrf2) is a master redox regulator as it controls transcription of several antioxidant genes. DEHP has been reported to cause dysregulation in Nrf2 signaling in vitro/in vivo and ASD subjects also exhibit oxidant-antioxidant imbalance.Therefore, this study attempted to delineate the effect of DEHP on Nrf2 signaling in neutrophils of ASD and typically developing healthy children (TDC) in vitro. Our data display that neutrophils of ASD subjects have dysregulated Nrf2 and hemeoxygenase-1 (HO-1) expression as compared to TDC subjects. DEHP treatment leads to elevation of oxidant stress in neutrophils of both ASD and TDC subjects, however TDC neutrophils have better antioxidant response to mitigate oxidative stress. This is depicted by enhancement of Nrf2/HO-1 signaling in TDC neutrophils in response to DEHP whereas ASD neutrophils fail to do so. These results suggest that plasticizer, DEHP may cause further dysregulation in Nrf2 signaling which may promote progression of ASD.

Гранулоцитарно-макрофагальный колониестимулирующий фактор: перспективы использования у детей с инфекционным мононуклеозом

Objective. To analyze the production of active oxygen species (AOS) by peripheral blood neutrophils in children with infectious mononucleosis (IM) after their exposure to granulocyte-macrophage colony-stimulating factor (GM-CSF) in vitro. Patients and methods. We examined 78 children aged 3 to 11 years in the acute period of IM (including 47 children aged 3–6 years and 31 children aged 7–11 years). The control group comprised 40 healthy children matched for age. Luminoldependent chemiluminescence (CL) of peripheral blood neutrophils was assessed using the method of De Sole et al. The following CL parameters were measured: time to reach the maximum (Tmax), maximum value (Imax), and the area (S) under the chemiluminescent curve. Results. Children with IM (from both age groups) demonstrated lower spontaneous lucigenin-dependent chemiluminescence of neutrophils than controls: Tmax (p < 0.001 and p = 0.036, respectively), Imax (p = 0.024 and p = 0.025), and S (p = 0.01). Incubation of neutrophils with GM-CSF caused changes in luminol-dependent chemiluminescence only in children with MI from both age groups: Tmax decreased, whereas Imax and S increased. IM patients aged 7–11 years were found to have higher levels of chemiluminescence of neutrophils exposed to GM-CSF in vitro than IM patients aged 3–6 years (Tmax (p < 0.001) and SGM-CSF/Ssp. (p = 0.024)). Conclusion. Our findings suggest that GM-CSF can increase functional activity of neutrophils. This might facilitate adaptive immunity at periphery. Key words: infectious mononucleosis, neutrophilic granulocytes, chemiluminescence of neutrophils, granulocyte-macrophage colony stimulating factor

PB1858 THE RESULTS OF THE COLONY‐FORMING ABILITY‘S DETERMINATION OF THE BONE MARROW IN CHILDREN WITH NEUTROPENIA

Background:Primary neutropenia is a rare hematological condition, mostly common in childhood. Neutropenic syndrome is heterogenous and may be a consequence of myelopoietic disorder in bone marrow, redistribution of neutrophils between the wall and circulating cell pools, enhanced destruction of granulocytes, and combination of these mechanisms. In this regard, the options for neutropenic conditions in children are very numerous. Determination of the pathogenetic mechanism of the development of neutropenia is possible only with a deep laboratory examination and is necessary to determine the tactics of patient‘s management. A cultural method of bone marrow's colony‐forming ability‘s assessing is one of the modern diagnostic approaches for cytopenias.Aims:Assessment the significance of the results of the bone marrow colony‐forming ability‘s determining at primary neutropenia in children.Methods:The results of laboratory tests of 10 patients examined for neutropenia were analyzed. The criterion of the diagnosis was considered an absolute decrease in the number of neutrophils in children over the age of 1 year ‐ less than 1,5 thousand in 1 μl of blood. The median of the age of patients was 9.5 (2.5‐17), among them there were 7 boys and 3 girls. To exclude system blood diseases, standard cytological and cytogenetic studies of the bone marrow were performed. The determination of the proliferative potential and differentiation capacity of the bone marrow was carried out by counting the number of granulocyte‐marcophagal‐erythrocyte‐megakaryocytic (CFU‐GEMM, normal 0‐8), granulocyte (CFU‐G, normal 7‐35), macrophage (CFU‐M, normal 1 ‐18), eosinophilic (CFU‐Eoz, norm 0‐22) and erythroid colonies (CFU‐Er, normal 20‐74) in a 14‐day culture. For this purpose, 0.2‐0.4 x 105 myelokaryocytes were introduced into the methylcellulose‐based medium (MethoCult H, StemCell Technologies). The number of formed colonies was considered as equal to the quantity of the corresponding colony‐forming units in the analyzed sample.Results:At the time of the examination, the number of leukocytes in the peripheral blood was 3.4 ± 1.3x103/μl, and the absolute neutrophil content was 969 ± 871.3/μl. Depending on the results of the bone marrow‘s colony‐forming ability patients were divided into 2 groups ‐ with normal and reduced CFU‐G content. In 7 out of 10 patients with neutropenia, a reduced content of granulocyte progenitor cells in the bone marrow was detected: the number of CFU‐G was 2‐6, the number of the remaining CFU was in the normal range (CFU‐GEMM ‐ 0‐5, CFU‐M ‐ 11‐40, CFU‐Er 3‐56, CFU‐Eoz 0‐15). The lowest absolute neutrophil content per unit of peripheral blood‘s volume (170‐1325 in 1 μl, median ‐ 920) was recorded at patients of this group. In case of dynamic observation, infectious complications of various localization and severity were registered, which, along with antibacterial drugs, required the administration of a granulocyte colony‐stimulating factor (G‐CSF). The use of G‐CSF was accompanied by a pronounced positive effect.In the remaining cases (3 out of 10 patients), the bone‐marrow colony‐forming ability was within the normal range (CFU‐G ‐ 12‐36, CFU‐M ‐ 18‐46, CFU‐Er ‐ 10‐56, CFU‐Eoz ‐ 2 ‐ 5). In the peripheral blood of these patients the absolute number of neutrophils was moderately reduced (1000‐1840 in 1 μl, median ‐ 1650). Upon further observation of this patients, indications for G‐CSF and severe infectious diseases were not observed.Summary/Conclusion:Assessment of the results of bone marrow‘s cultural research allows to predict primary neutropenia‘s course and administrate pathogenic therapy.

FEATURES OF PATHOGENESIS, THE ROLE OF OXIDATIVE STRESS, ANTIOXIDANT SYSTEM, AND THE FUNCTIONAL STATUS OF NEUTROPHILS IN CHILDREN WITH COMMUNITY-ACQUIRED PNEUMONIA

The review presents data on the incidence rate, features of pathogenesis, antioxidant status, and functional and metabolic activity of neutrophils in children with community-acquired pneumonia.

Modeling Transcriptional Rewiring in Neutrophils Through the Course of Treated Juvenile Idiopathic Arthritis

Neutrophils in children with the polyarticular form of juvenile idiopathic arthritis (JIA) display abnormal transcriptional patterns linked to fundamental metabolic derangements. In this study, we sought to determine the effects of therapy on mRNA and miRNA expression networks in polyarticular JIA. Using exon and miRNA microarrays, we studied children with untreated active JIA (ADU, n = 35), children with active disease on therapy with methotrexate ± etanercept (ADT, n = 26), and children with inactive disease also on therapy (ID, n = 14). We compared the results to findings from healthy control children (HC, n = 35). We found substantial re-ordering of mRNA and miRNA expression networks after the initiation of therapy. Each disease state was associated with a distinct transcriptional profile, with the ADT state differing the most from HC, and ID more strongly resembling HC. Changes at the mRNA level were mirrored in changes in miRNA expression patterns. The analysis of the expression dynamics from differentially expressed genes across three disease states indicated that therapeutic response is a complex process. This process does not simply involve genes slowly correcting in a linear fashion over time. Computational modeling of miRNA and transcription factor (TF) co-regulatory networks demonstrated that combinational regulation of miRNA and TF might play an important role in dynamic transcriptome changes.

IL-5Rα expression on airway neutrophils in children with treatment-refractory asthma

IL-5Rα expression on airway neutrophils in children with treatment-refractory asthma

THE FEATURES OF ZINC METABOLISM IN CHILDREN DEPENDING ON DIFFERENT ENVIRONMENTAL LIVING CONDITIONS

The article presents a study of zinc concentrations in serum and neutrophils in children living in ecologically unfavourable regions. The results of the study have shown that the children from polluted regions have a deficiency of zinc in neutrophils and in serum. Such deficiency is an informative indicator of cellular metabolism and disorders caused by exogenous pollutants

ANALISIS PERBEDAAN JUMLAH NEUTROFIL ANTARA ANAK DOWN SYNDROME DAN ANAK SEHAT - Studi Pada SLB-C Widya Bhakti Semarang dan Mi Mirfa’ul Ulum

Background: Down syndrome (DS) is a congenital disorder caused by abnormalities of chromosome 21, resulting in migration defect of neutrophils, specifically in GCF as a marker of increasing periodontal infection. This study aimed to analyze the difference in neutrophil numbers between down syndrome and healthy children.Method: This research was an analytic observational with cross sectional design, and divided into two groups. The control group is consisted of healthy children and the other is consisted of down syndrome children. GCF was taken using paper point number 45-50 for 30 seconds, then it smeared into object glass and painted with giemsa staining. Observations was done by light microscopy with 1000 times magnification.Result: The result of studies with p<0.05 was indicating a significant difference of neutrophil numbers between children with down syndrome and the healthy group.Conclusion: This study concluded that there was a difference in neutrophil numbers due to the migration defect of neutrophils in children with down syndrome, that can cause proneness to periodontal infections.

The functional status of neutrophils in children with morbidity of chronic adenoiditis

Neutrophils have recently been attracting significant attention, due to appearance of new information on functional heterogeneity of this cell population that significantly determines pathways and features of pathological process. Objective: to determine morphological and functional features of neutrophils and structure of pharyngeal tonsil in children with adenoiditis and otitis media with effusion. Materials and Methods: In 38 children aged 3 to 7 years (25 - with uncomplicated chronic adenoiditis, 13 - with adenoiditis complicated with secretory otitis media) activity of acid and alkaline phosphatases and activity of cationic proteins was determined in peripheral blood neutrophils by cytochemical methods; NBT test was performed. Relative area of follicles, diffuse lymphoid tissue, blood vessels, fibrous tissue, as well as the presence and composition of intraepithelial infiltration, type of surface epithelium was evaluated on histological specimens of biopsies obtained during adenotomy (10 - in patients with uncomplicated chronic adenoiditis, 13 - with chronic adenoiditis complicated with secretory otitis media). Results: Decrease of the relative area of follicles (p = 0.04) as well as decline of the activity of acid phosphatase in the blood neutrophils [0.26 (0.22, 0.32) vs 0.32 (0.28; 0.36); p = 0.03] was observed during complicated course of chronic adenoiditis compared to uncomplicated form of the disease. Activity of oxygen-dependent mechanisms of cytotoxicity of peripheral blood neutrophils, assessed in NBT-test, did not differ between children with complicated and uncomplicated course of chronic adenoiditis. Conclusion: Reduced neutrophil acid phosphatase activity with intact ability to generate reactive oxygen species may be one of the causative factors of chronic adenoiditis, subepithelial morphological rearrangements in lymphoid tissue and development of exudative otitis media.

Effects of malnutrition on oxidative burst functions and infection episodes in children with acute lymphoblastic leukemia

The aim of this study was to determine the effect of malnutrition on oxidative burst functions (OBF) of neutrophils in children with acute lymphoblastic leukemia (ALL). Twenty-eight patients with ALL and thirty healthy controls were enrolled to the study. Thirteen patients with ALL were found to have malnutrition. While neutrophil OBF of ALL patients without malnutrition were studied both before induction chemotherapy and 3months after, the same functions in ALL patients with malnutrition were studied both before induction chemotherapy and when the nutritional status improved. Control group were studied at admission and 3months later. The OBF of ALL patients with and without malnutrition before induction chemotherapy were found to be significantly lower than the control group (P=0.009), whereas the OBF were found to be similar in both patient groups with ALL (P=0.27). The median infection episode rate and the duration of antibiotics therapy during the study period were similar in both patient groups with ALL. The repeated OBF of both patient groups with ALL were shown to increase to similar values with the control group in the third month of chemotherapy (P=0.002). The median infection episode rate during the first month of chemotherapy was shown to decrease significantly during the third month of chemotherapy in both patient with ALL groups (P<0.001). We have not been able to demonstrate an overt effect of malnutrition on OBF. However, our results still need to be verified via further larger scaled studies of OBF in leukemic children with and without malnutrition.

Failure of regulation results in an amplified oxidation burst by neutrophils in children with primary nephrotic syndrome

The mechanism responsible for proteinuria in non-genetic idiopathic nephrotic syndrome (iNS) is unknown. Animal models suggest an effect of free radicals on podocytes, and indirect evidence in humans confirm this implication. We determined the oxidative burst by blood CD15+ polymorphonucleates (PMN) utilizing the 5-(and-6)-carboxy-2',7'-dichlorofluorescin diacetate (DCF-DA) fluorescence assay in 38 children with iNS. Results were compared with PMN from normal subjects and patients with renal pathologies considered traditionally to be models of oxidative stress [six anti-neutrophil cytoplasmic autoantibody (ANCA) vasculitis, seven post-infectious glomerulonephritis]. Radicals of oxygen (ROS) production was finally determined in a patient with immunodeficiency, polyendocrinopathy, enteropathy X-linked (IPEX) and in seven iNS children after treatment with Rituximab. Results demonstrated a 10-fold increase of ROS production by resting PMN in iNS compared to normal PMN. When PMN were separated from other cells, ROS increased significantly in all conditions while a near-normal production was restored by adding autologous cells and/or supernatants in controls, vasculitis and post-infectious glomerulonephritis but not in iNS. Results indicated that the oxidative burst was regulated by soluble factors and that this regulatory circuit was altered in iNS. PMN obtained from a child with IPEX produced 100 times more ROS during exacerbation of clinical symptoms and restored to a near normal-level in remission. Rituximab decreased ROS production by 60%. In conclusion, our study shows that oxidant production is increased in iNS for an imbalance between PMN and other blood cells. Regulatory T cells (Tregs) and CD20 are probably involved in this regulation. Overall, our observations reinforce the concept that oxidants deriving from PMN are implicated in iNS.

Glucocorticoid receptor mRNA levels are selectively decreased in neutrophils of children with sepsis

ObjectiveCorticosteroids are used in sepsis treatment to benefit outcome. However, discussion remains on which patients will benefit from treatment. Inter-individual variations in cortisol sensitivity, mediated through the glucocorticoid receptor, might play a role in the observed differences. Our aim was to study changes in mRNA levels of three glucocorticoid receptor splice variants in neutrophils of children with sepsis.Patients and designTwenty-three children admitted to the pediatric intensive care unit with sepsis or septic shock were included. Neutrophils were isolated at days 0, 3 and 7, and after recovery (>3 months). mRNA levels of the glucocorticoid receptor splice variants GR-α (determining most of the cortisol effect), GR-P (increasing GR-α effect) and GR-β (inhibitor of GR-α) were measured quantitatively.Main resultsNeutrophils from sepsis patients showed decreased levels of glucocorticoid receptor mRNA of the GR-α and GR-P splice variants on day 0 compared to after recovery. GR-α and GR-P mRNA levels showed a gradual recovery on days 3 and 7 and normalized after recovery. GR-β mRNA levels did not change significantly during sepsis. GR expression was negatively correlated to interleukin-6 (a measure of disease severity, r = −0.60, P = 0.009).ConclusionsChildren with sepsis or septic shock showed a transient depression of glucocorticoid receptor mRNA in their neutrophils. This feature may represent a tissue-specific adaptation during sepsis leading to increased cortisol resistance of neutrophils. Our study adds to understanding the mechanism of cortisol sensitivity in immune cells. Future treatment strategies, aiming at timing and tissue specific regulation of glucocorticoids, might benefit patients with sepsis or septic shock.

Increased nitric oxide production by neutrophils in early stage of Kawasaki disease

Recent observations suggested that nitric oxide (NO) has a role in triggering the early endothelial dysfunction in Kawasaki disease (KD). We investigated the amount of NO in conjunction with reactive oxygen species (ROS) produced by neutrophils in children with acute KD by a newly developed flow cytometric analysis. Forty children with acute KD (n = 14), non-KD febrile disease (n = 14), and afebrile control (n = 12) were enrolled (age, 3 to 88 months). Neutrophils in KD produced significantly higher amount of NO compared to others (p < 0.05). With regard to ROS, significant increase was not only found in KD but also in non-KD febrile children (p < 0.05 and p < 0.01, respectively). In KD patients, the amount of NO produced by neutrophils decreased after immunoglobulin (IVIG) treatment, while there was no significant change in ROS production. The amount of NO in KD patients also correlated well with the days from the onset. One patient who developed coronary arterial lesion showed the highest value of NO. In conclusion, neutrophils in acute KD generate both NO and ROS considerably, while NO production is exclusive in the early stage of KD before IVIG treatment. Abnormal immune system in KD might be characterized by an overproduction of NO, whereas the role of NO in endothelial damage remains to be elucidated.

Effect of cardiopulmonary bypass on CD11/CD18 expression of neutrophils in children undergoing cardiac surgery

To investigate the changes in perioperative expression level of CD11/CD18 of neutrophils in children undergoing cardiac surgery with cardiopulmonary bypass (CPB). Thirty children patients with congenital heart disease underwent cardiac surgery with CPB (CPB group) and the control group consisted of 20 children who received thoracic or general surgery without CPB. Blood samples were drawn at the following time points: pre-surgery, 15 min after onset of CPB, immediately after CPB, 2 h after surgery and on the 1st, 2nd, 3rd postoperative day. D11/CD18 expression on neutrophils and serum concentration of IL-6 and IL-8 were analyzed by flow cytometry and enzyme-linked immunosorbent assay, respectively. In CPB group plasma levels of IL-6 and IL-8 increased significantly and peaked at 2 h after initiation of CPB (P<0.05), and descended to the after-anesthesia level at 3rd day after operation. In non-CPB group there was a similar trend of changes in IL-6 and IL-8, but to a much lesser extent. The level of CD11b/CD18 in CPB group began to increase significantly and peaked at 15 min after initiation of CPB (P <0.05), and descended to the after-anesthesia level at 2 h after operation. There was no significant changes of CD11b/CD18 in control group (P >0.05). No significant differences were detected at any time points with respect to expression of CD11a/CD18 and CD11c/CD18 in both groups (P >0.05). CPB surgery of children can cause increasing of the CD11b/CD18 expression level of neutrophil but has no significant effect on CD11a/CD18 and CD11c/CD18. CD11b/CD18 may play an important role in the systemic inflammation induced by CPB.