Integrin-mediated adhesive properties of neutrophils are reduced by hyperbaric oxygen therapy in patients with chronic non-healing wound.

In recent years, several studies suggested that the ability of hyperbaric oxygen therapy (HBOT) to promote healing in patients with diabetic ulcers and chronic wounds is due to the reduction of inflammatory cytokines and to a significant decrease in neutrophils recruitment to the damaged area. α4 and ß2 integrins are receptors mediating the neutrophil adhesion to the endothelium and the comprehension of the effects of hyperbaric oxygenation on their expression and functions in neutrophils could be of great importance for the design of novel therapeutic protocols focused on anti-inflammatory agents. In this study, the α4 and ß2 integrins' expression and functions have been evaluated in human primary neutrophils obtained from patients with chronic non-healing wounds and undergoing a prolonged HBOT (150 kPa per 90 minutes). The effect of a peptidomimetic α4ß1 integrin antagonist has been also analyzed under these conditions. A statistically significant decrease (68%) in ß2 integrin expression on neutrophils was observed during the treatment with HBO and maintained one month after the last treatment, while α4 integrin levels remained unchanged. However, cell adhesion function of both neutrophilic integrins α4ß1 and ß2 was significantly reduced 70 and 67%, respectively), but α4ß1 integrin was still sensitive to antagonist inhibition in the presence of fibronectin, suggesting that a combined therapy between HBOT and integrin antagonists could have greater antinflammatory efficacy.

Long term outcome of eight patients with type 1 Leukocyte Adhesion Deficiency (LAD-1): Not only infections, but high risk of autoimmune complications.

Leukocyte Adhesion Deficiency type 1 (LAD-1) is a rare primary immunodeficiency due to mutations in the gene encoding for the common ß-chain of the ß2 integrin family (CD18). Herein, we describe clinical manifestations and long-term complications of eight LAD-1 patients. Four LAD-1 patients were treated with hematopoietic stem cell transplantation (HSCT), while the remaining four, including two with moderate LAD-1 deficiency, received continuous antibiotic prophylaxis. Untreated patients presented numerous infections and autoimmune manifestations. In particular, two of them developed renal and intestinal autoimmune diseases, despite the expression of Beta-2 integrin was partially conserved. Other two LAD-1 patients developed type 1 diabetes and autoimmune cytopenia after HSCT, suggesting that HSCT is effective for preventing infections in LAD-1, but does not prevent the risk of the autoimmune complications.

Necrotizing Ulcer After BCG Vaccination in a Girl With Leukocyte-adhesion Deficiency Type 1.

Leukocyte-adhesion deficiency-1 is a recessively inherited disorder associated with recurrent bacterial infections, severe periodontitis, peripheral leukocytosis, and impaired wound healing. We diagnosed moderate-type leukocyte-adhesion deficiency-1 in a 7-year-old girl who developed a necrotizing ulcer after Bacillus Calmette-Guerin vaccination. The patient showed moderate expression of CD18 in neutrophils with a homozygous splice mutation with c.41_c.58+2dup20 of ITGB2 and experienced recurrent severe infections complicated with systemic lupus erythematosus. She received hematopoietic stem cell transplantation from a matched elder brother with heterozygous mutation of ITGB2, and has since remained free of infection and systemic lupus erythematosus symptoms without immunosuppression therapy.

Kindlin 3 (FERMT3) is associated with unstable atherosclerotic plaques, anti-inflammatory type II macrophages and upregulation of beta-2 integrins in all major arterial beds.

BACKGROUND: Kindlins (FERMT) are cytoplasmic proteins required for integrin (ITG) activation, leukocyte transmigration, platelet aggregation and thrombosis. Characterization of kindlins and their association with atherosclerotic plaques in human(s) is lacking. METHODS AND RESULTS: Exploratory microarray (MA) was first performed followed by selective quantitative validation of robustly expressed genes with qRT-PCR low-density array (LDA). In LDA, ITGA1 (1.30-fold, p = 0.041) and ITGB3 (1.37-fold, p = 0.036) were upregulated in whole blood samples of patients with coronary artery disease (CAD) compared to healthy controls. In arterial plaques, both robustly expressed transcript variants of FERMT3 (MA: 5.90- and 3.4-fold; LDA: 3.99-fold, p < 0.0001 for all) and ITGB2 (MA: 4.81- and 4.92-fold; LDA: 5.29-fold, p < 0.0001 for all) were upregulated while FERMT2 was downregulated (MA: -1.61-fold; LDA: -2.88-fold, p < 0.0001 for both). The other integrins (ITGA1, ITGAV, ITGB3, ITGB5) were downregulated. All these results were replicated in at least one arterial bed. The latter FERMT3 transcript variant associated with unstable plaques (p = 0.0004). FERMT3 correlated with M2 macrophage markers and in hierarchical cluster analysis clustered with inflammatory and macrophage markers, while FERMT2 correlated with SMC-rich plaque markers and clustered with SMC markers. In confocal immunofluorescence analysis, FERMT3 protein colocalized with abundant CD68-positive cells of monocytic origin in the atherosclerotic plaques, while co-localization of FERMT3 with HHF35 indicative of smooth muscle cells was low. CONCLUSIONS: Kindlin-3 (FERMT3) is upregulated in atherosclerotic, especially unstable plaques, mainly in cells of monocytic origin and of M2 type. Simultaneous upregulation of ITGB2 suggests a synergistic effect on leukocyte adherence and transmigration into the vessel wall.

Exposure to Leishmania braziliensis triggers neutrophil activation and apoptosis.

BACKGROUND: Neutrophils are the first line of defense against invading pathogens and are rapidly recruited to the sites of Leishmania inoculation. During Leishmania braziliensis infection, depletion of inflammatory cells significantly increases the parasite load whereas co-inoculation of neutrophils plus L. braziliensis had an opposite effect. Moreover, the co-culture of infected macrophages and neutrophils also induced parasite killing leading us to ask how neutrophils alone respond to an L. braziliensis exposure. Herein we focused on understanding the interaction between neutrophils and L. braziliensis, exploring cell activation and apoptotic fate. METHODS AND FINDINGS: Inoculation of serum-opsonized L. braziliensis promastigotes in mice induced neutrophil accumulation in vivo, peaking at 24 h. In vitro, exposure of thyoglycollate-elicited inflammatory or bone marrow neutrophils to L. braziliensis modulated the expression of surface molecules such as CD18 and CD62L, and induced the oxidative burst. Using mCherry-expressing L. braziliensis, we determined that such effects were mainly observed in infected and not in bystander cells. Neutrophil activation following contact with L. braziliensis was also confirmed by the release of TNF-α and neutrophil elastase. Lastly, neutrophils infected with L. braziliensis but not with L. major displayed markers of early apoptosis. CONCLUSIONS: We show that L. braziliensis induces neutrophil recruitment in vivo and that neutrophils exposed to the parasite in vitro respond through activation and release of inflammatory mediators. This outcome may impact on parasite elimination, particularly at the early stages of infection.

Expression of CD11b as an adhesion molecule on neutrophils in children with Kawasaki disease.

Inflammation of blood vessels is a characteristic feature of Kawasaki disease. Neutrophils play a key role in the inflammatory responses where movement of neutrophils toward the site of inflammation depends on CD11b/CD18 expression as adhesion molecules on these cells. The purpose of this study was to investigate CD11b/CD18 expression in patients with Kawasaki disease upon diagnosis and after treatment.The study included 20 children with Kawasaki disease aged from 3 months to 8 years. Mean fluorescence intensity of CD11b levels on diagnosis and at 1-2 and 6 weeks after intravenous immunoglobulin (IVIG) therapy was measured in these patients. Level of CD11b was measured in age-matched healthy children and febrile children (each 21) as negative and positive controls, respectively.Mean fluorescence intensity of CD11b in Kawasaki patients was lower than that of the control groups before and after 1-2 weeks of IVIG therapy. There were no significant differences in CD11b in Kawasaki patients either with aneurysm or without aneurysm. The CD11b levels at the diagnosis time and after treatment with IVIG in our patients with Kawasaki were lower than the control groups.

Modulation of Beta2 and Beta3 integrins in experimental colitis induced by iodoacetamide and enteropathogenic E. coli.

Integrins can modulate the infiltration of inflammatory cells and the secretion of various inflammatory mediators, essential players in the pathogenesis of colitis. This study explores the role of beta2 and beta3 integrin signaling and their possible role in experimental colitis. A total of 160 adult male Sprague-Dawly rats were divided into 4 equal groups: methylcellulose, bacteria, iodoacetamide and iodoacetamide plus bacteria. Clinical symptoms and signs of colitis were checked daily and colonic tissues were biopsied on days 3, 14, 28, and 56 post induction. Histological studies along with histochemical analysis and polymerase chain reaction of beta2, beta3 and alphavbeta3 were performed according to standard procedures. The symptoms and signs were consistent with previously reported data on active colitis. The highest expression of beta3 integrin was in the combined treatment mostly on platelets, endothelial and inflammatory cells. In the same group, the expression of alphavbeta3 integrin complex reached the highest score after 56 days in all colonic layers. Beta2 integrin expression showed a 3-4-fold increase in the combined treatment group at all time points and kept increasing till day 56. It was mostly expressed in the mucosa and submucosa. In addition, the expression of both αvβ3 and αiiβ3 integrins was also elevated 2- to 10-fold, respectively, in the same colitis groups throughout the duration of the experiment. In conclusion, the combined treatment of IA and Enteropathogenic E. coli led to a significant upregulation of all the tested integrins throughout the experimental duration. Such upregulation of integrins could have contributed to the increase and chronicity of inflammation.

Impedimetric immunosensor for the detection of circulating pro-inflammatory monocytes as infection markers.

Circulating blood monocytes belong to the first line of defense against pathogens and inflammation. Monocytes can be divided into three populations defined by the expression of the cell surface molecules, CD 14 and CD 16. The CD 14(++) CD 16(-) cells, called "classical" monocytes, represent 85% to 95% of the total monocytes in a healthy person whereas CD 14(-) CD 16(+), called "proinflammatory" monocytes, are found in greater numbers in the blood of patients with acute inflammation and infectious diseases. This increase in the concentration of proinflammatory monocytes can be a good indicator of an infectious state. This study presents an immunosensor based on impedance detection for specific cell trapping of classical and proinflammatory monocytes. The grafting of specific antibodies (CD 14 or CD 16) was based on the use of mixed SAM associated with protein G. Each step of the functionalization was characterized by electrochemical methods, quartz crystal microbalance and atomic force microscopy. Faradaic electrochemical impedance spectroscopy and voltametric analysis confirmed the success of the modification process with a surface coverage reaching 92% for the antibody layer. The increase in the deposited mass at each step of the modification process confirmed this results revealing that one protein G in two was bound to an antibody. The cell trapping capacity, evaluated by the variation in the film resistance using non-faradaic impedance spectroscopy revealed that the cell trapping is selective, depending on the specific antibody grafted and quantitative with the range of detection being 1000 to 30,000 infected cells. This range of detection is consistent with the application targeted.

Comparison of innate immune responses and somatotropic axis components of Holstein and Montbéliarde-sired crossbred dairy cows during the transition period.

Objectives were to compare parameters related to innate immune responses and somatotropic axis of Holstein (HO) and Montbéliarde (MO)-sired crossbred cows during the transition from late gestation to early lactation. Cows (40 HO and 47 MO-sired crossbred) were enrolled in the study 45d before expected calving date (study d 0=calving). Polymorphonuclear leukocytes (PMNL) isolated from blood samples collected weekly from study d -7 to 21 and on study d 42 were used for determination of percentage of PMNL positive for phagocytosis (PA+) and oxidative burst (OB+), intensity of PA and OB, percentage of PMNL expressing CD18 (CD18+) and L-selectin (LS+), and intensity of CD18 and LS expression. Blood was sampled weekly from study d -7 to 14 and on study d 28, 42, and 56 for determination of insulin, growth hormone (GH), leptin, and insulin-like growth factor (IGF)-1 concentrations. Blood sampled weekly from study d -14 to 21 and on study d 42 was used to determine cortisol concentration. Liver biopsies were performed on study d -14, 7, 14, and 28 for determination of mRNA expression for insulin receptor B (IRB), total GH receptor (GHRtot), GHR variant 1A (GHR1A), and IGF-1. Data were analyzed by ANOVA for repeated measures or by ANOVA using the GLM procedure of SAS (SAS Institute Inc., Cary, NC). Intensity of CD18 expression was greater in PMNL from crossbred cows compared with PMNL from HO cows [1,482.1 ± 82.3 vs. 1,286.6 ± 69.8 geometric mean fluorescence intensity (GMFI)]. Furthermore, among HO cows, the percentage of PA+ PMNL on study d -7 (64.4 ± 5.2%) tended to be greater than on study d 0 (57.1 ± 5.1%), but no differences in percentage of PA+ PMNL between study d -7 and 0 were observed in crossbred cows. Similarly, intensity of PA in PA+ PMNL from HO cows decreased from study d -7 to 0 (4,750.6 ± 1,217.0 vs. 1,964.7 ± 1,227.9 GMFI), but no changes in intensity of PA in PA+ PMNL from crossbred cows were observed. On study d 0, intensity of PA tended to be reduced in PA+ PMNL from HO cows compared with PA+ PMNL from crossbred cows (1,964.7 ± 1,227.9 vs. 4,688.1 ± 1,271.8 GMFI). Concentrations of GH (7.4 ± 0.4 vs. 5.1 ± 0.4 ng/mL) and cortisol (9.5 ± 0.8 vs. 7.1 ± 0.8 ng/mL) were greater for HO than for crossbred cows. Crossbred cows had improved innate immune responses compared with HO cows, as determined by a lack of decrease in intensity of PA on the day of calving, which may result in improved health. Furthermore, HO cows appeared to be less sensitive to the negative feedback of IGF-1 on GH secretion because cows from both breeds had similar IGF-1 concentrations but MO-sired crossbred cows had greater GH concentrations.

Long-term leukocyte filtration should be avoided during extracorporeal circulation.

Filtration during extracorporeal circulation (ECC) not only removes but also activates leukocytes; therefore, long-term leukocyte filtration may cause adverse effects. In the present study, we tested this hypothesis by priming ECC with 300 mL of canine blood and examining filtration effects in 3 groups (n = 6 each) during 60 min ECC. In the control group (Group C) blood was filtrated with an arterial filter for 60 min; in long-term (Group L) and short-term (Group S) groups, blood was filtrated with a leukocyte filter for 60 and 5 min. We found that about 90% of leukocytes were removed after 5 min of filtration in both Groups L and S. Although leukocyte count continued to reduce, mean fluorescent intensities of CD11/CD18, free hemoglobin, and neutrophil elastase increased in Group L and were higher than those in Groups C and S at 60 min. Leukocyte rupture, cytoplasmic leakage, and circulating naked nuclei were also found in Group L. The data support our hypothesis that long-term filtration can induce inflammation and lead to leukocyte destruction.

Increased frequency and clinical significance of myeloid-derived suppressor cells in human colorectal carcinoma.

AIM: To investigate the frequency and clinical significance of the myeloid-derived suppressor cells (MDSC) in human colorectal carcinoma (CRC). METHODS: Samples of peripheral blood and tumor tissue from 49 CRC patients were analyzed. Mononuclear cells were isolated by Ficoll-Hypaque density gradient centrifugation and were subjected to a flow cytometry-based immunophenotypic analysis. RESULTS: A considerable increase in the percentage of CD33⁺HLA-DR⁻ MDSCs was observed in the peripheral blood (1.89% ± 0.75%) and tumor tissues (2.99% ± 1.29%) of CRC patients as compared with that in the peripheral blood of healthy controls (0.54% ± 0.35%). This expanded CD33⁺HLA-DR⁻ subset exhibited immature myeloid cell markers, but not lineage markers, and showed up-regulation of CD18/CD11b expression as compared with the MDSCs from healthy donors. Further studies showed that the MDSC proportion in CRC peripheral blood was correlated with nodal metastasis(P = 0.023), whereas that in tumor tissues was correlated with nodal/distant metastasis (P = 0.016/P = 0.047) and tumor stage (P = 0.028), suggesting the involvement of MDSCs in CRC tumor development. CONCLUSION: Characterization of MDSCs in CRC suggests the clinical significance of circulating and tumor-infiltrating MDSCs and may provide new insights into the CRC immunotherapy targeting MDSCs.

Clinical profile of leukocyte adhesion deficiency type I.

Leukocyte adhesion deficiency type I (LAD-I) is a rare, inherited immunodeficiency with defect in the recruitment of leukocyte to the site of inflammation. Patients with severe LAD-I have absent or markedly reduced expression of CD18 and CD11. Here we report clinical profile of 7 cases of LAD-I diagnosed at our center over a period of 3 years. Recurrent skin and mucous membrane infections were the major presenting manifestations. All children had a history of delayed cord separation.

Label-free proteomics reveals decreased expression of CD18 and AKNA in peripheral CD4+ T cells from patients with Vogt-Koyanagi-Harada syndrome.

Vogt-Koyanagi-Harada (VKH) syndrome is a systemic autoimmune disease. CD4(+) T cells have been shown to be involved in autoimmune diseases including VKH syndrome. To screen aberrantly expressed membrane proteins in CD4(+) T cell from patients with active VKH syndrome, blood samples were taken from five patients with active VKH syndrome and five healthy individuals. A label-free quantitative proteomic strategy was used to identify the differently expressed proteins between the two groups. The results revealed that the expression of 102 peptides was significantly altered (p<0.05) between two groups and matched amino acid sequences of proteins deposited in the international protein index (ipi.HUMAN.v3.36.fasta). The identified peptides corresponded to 64 proteins, in which 30 showed more than a 1.5-fold difference between the two groups. The decreased expression of CD18 and AKNA transcription factor (AKNA), both being three-fold lower than controls in expression identified by the label-free method, was further confirmed in an additional group of five active VKH patients and six normal individuals using the Western blot technique. A significantly decreased expression of CD18 and AKNA suggests a role for both proteins in the pathogenesis of this syndrome.

Delay of migrating leukocytes by the basement membrane deposited by endothelial cells in long-term culture.

We investigated the migration of human leukocytes through endothelial cells (EC), and particularly their underlying basement membrane (BM). EC were cultured for 20days on 3µm-pore filters or collagen gels to form a distinct BM, and then treated with tumour necrosis factor-α, interleukin-1ß or interferon-γ. Neutrophil migration through the cytokine-treated EC and BM was delayed for 20-day compared to 4-day cultures. The BM alone obstructed chemotaxis of neutrophils, and if fresh EC were briefly cultured on stripped BM, there was again a hold-up in migration. In studies with lymphocytes and monocytes, we could detect little hold-up of migration for 20-day versus 4-day cultures, in either the filter- or gel-based models. Direct microscopic observations showed that BM also held-up neutrophil migration under conditions of flow. Treatment of upper and/or lower compartments of filters with antibodies against integrins, showed that neutrophil migration through the endothelial monolayer was dependent on ß(2)-integrins, but not ß1- or ß(3)-integrins. Migration from the subendothelial compartment was supported by ß1- and ß(2)-integrins for all cultures, but blockade of ß(3)-integrin only inhibited migration effectively for 20-day cultures. Flow cytometry indicated that there was no net increase in expression of ß1- or ß3-integrins during neutrophil migration, and that their specific subendothelial function was likely dependent on turnover of integrins during migration. These studies show that BM is a distinct barrier to migration of human neutrophils, and that ß(3)-integrins are particularly important in crossing this barrier. The lesser effect of BM on lymphocytes and monocytes supports the concept that crossing the BM is a separate, leukocyte-specific, regulated step in migration.

Interactive inhibitory effects of formoterol and montelukast on activated human neutrophils.

The research question addressed in the current study was: do formoterol (1 and 10 nM) and montelukast (2 µM) possess interactive inhibitory effects on activated human neutrophils, particularly in relation to alterations in cyclic AMP and cytosolic Ca²(+) fluxes? Isolated human blood neutrophils were activated with the chemoattractant N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP) (1 µM) in combination with cytochalasin B (CB; 3 µM). Fura-2-acetoxymethyl ester-based spectrofluorimetry, lucigenin-enhanced chemiluminescence, colorimetric and flow cytometric procedures were used to measure cytosolic Ca²(+) fluxes, production of superoxide, elastase release and beta-2 integrin (CR3) expression, respectively, while cyclic AMP and leukotriene (LT)B4 were assayed using competitive binding ELISA procedures. Activation of the cells with fMLP/CB resulted in abrupt and sustained increases in cytosolic Ca²(+), as well as release of elastase and production of superoxide and LTB4, and expression of CR3, all of which were attenuated by formoterol and montelukast individually, and especially by the combination of these agents. These anti-inflammatory effects of each agent, as well as the combination, were associated with significant increases in cyclic AMP. The findings of the current study may explain the efficacy of montelukast and formoterol when used in combination with inhaled corticosteroids in the treatment of severe asthma, possibly by controlling neutrophil-driven inflammation of the airways.

Periodontal inflammation and bone loss in aged mice.

BACKGROUND AND OBJECTIVE: Young mice do not develop measurable periodontal bone loss, unless heavily infected with human periodontal pathogens. However, mice with a genetically altered immune system are unable to control their own oral flora and develop periodontitis early in life. Based on the potential of the indigenous oral microbiota to cause periodontitis, we hypothesized that normal mice may ultimately develop inflammatory periodontal bone loss, i.e. as a function of age. If confirmed, this could serve as an aging model of chronic periodontitis. MATERIAL AND METHODS: Periodontal bone levels were measured as the distance from the cementoenamel junction to the alveolar bone crest in young mice (8-10 wk of age), old mice (>or= 18 mo of age) and mice of intermediate ages. Differential expression of inflammatory mediators in the gingivae of young and old mice was determined by quantitative real-time PCR. RESULTS: In comparison with young mice, old mice displayed significantly (p < 0.05) increased periodontal bone loss, accompanied by elevated expression of proinflammatory cytokines (interleukin-1 beta, tumor necrosis factor alpha and interleukin-17A) and innate immune receptors involved in the induction or amplification of inflammation (Toll-like receptor 2, CD14, CD11b, CD18, complement C5a receptor and triggering receptor expressed on myeloid cells 3). CONCLUSION: Mice develop naturally induced periodontal bone loss as a function of age. This aging model of periodontitis represents a genuinely chronic model to study mechanisms of periodontal tissue destruction.

Assessment of zona pellucida glycoprotein and integrin transcript contents in porcine oocytes.

Using reverse transcription and real-time quantitative PCR analysis we evaluated the transcript levels of integrins (alphaL, alphaM, beta1, and beta6), CD9 and CD18 antigens as well as zona pellucida glycoproteins (pZP1, pZP2, pZP3 and pZP3alpha) in oocytes isolated from puberal gilts (n=20) and multiparous sows (n=20). We found significantly (p<0.05) higher transcript contents of alphaL, alphaM, beta1, and beta integrins, CD9 antigen, and pZP2 and pZP3 in puberal gilt oocytes compared to multiparous sow oocytes. Our results suggest that a decrease in the level of oocyte transcripts encoding essential proteins involved in oocyte fertilization may be associated with increased porcine female age.

Epithelial bone marrow cells in patients with advanced esophageal squamous cell carcinoma.

The aim of the current study was to examine epithelial cells in the bone marrow and peripheral blood of patients with various stages of esophageal squamous cell cancer prior to surgical treatment and to analyze the prognostic significance of these carcinoma cells deposits to the stage of the disease and applied surgical therapy. Thirty-two patients (25 men and 7 women), and 5 healthy bone marrow donors serving as controls were studied. Bone marrow samples were evaluated by light microscopy and examined by flow cytofluorometry. Cells were phenotypically analyzed for the antigens CD45- and CD18+ and/or EMA+. Results are presented as the number of cells revealing the investigated phenotype per 10 (5)analyzed cells. CD18 was expressed in the bone marrow cells of 15 of the 32 (47%) patients and EMA in 20/32 (62%), but not in peripheral blood. In 13 of the 32 pts (41%), co-expression of CD18 and EMA was observed. Patients with the proportion of marrow erythroblasts below 15% had higher numbers of CD18+ and EMA+ cells and there was a negative correlation between the number of erythroblasts and EMA+ cells (r=0.54, p=0.01). In patients with esophageal cancer and anemia, the number of EMA+ cells was higher (p=0.05) and the percentage of erythropoietic cells in the bone marrow was lower (p=0.01). In conclusion, flow cytofluorometry using anti-cytokeratin and anti-EMA antibodies may be useful in evaluating microdeposits of esophageal squamous cells in bone marrow. A dysfunctioning erythropoietic system causing anemia can be a first signal for the presence of malignant cell microdeposits in the marrow of patients with esophageal carcinoma.

[Changes of neutrophil functions after cardiopulmonary bypass: experiment with dogs].

OBJECTIVE: To investigate if increase of adhesion function and capability to destroy and decrease of phagocytosis of neutrophils occur after cardiopulmonary bypass (CPB). METHODS: 12 mongrel dogs were randomly divided into two equal groups: CPB group, weaned from CPB after 100 min of CPB; and sham group standing for 100 min without CPB. All dogs were observed for another 4 hrs. Blood samples were collected from the femoral vein before heparinization and by the end of experiment to measure the white blood cell count and classification, and expression of CD11b and CD18. Tissue samples of the right and left lungs were collected before heparinization and by the end of experiment. The expression of CD11b/CD18 in neutrophils, myeloperoxidase (MPO) activities in lung tissue, and pulmonary function were determined to access the adhesion function of neutrophils and the injuries to tissues. The phagocytotic activities, the release of MPO and the generation of oxygen free radical induced by IL-8 were surveyed to access the immune function of neutrophils. RESULTS: The fluorescence level of CD11b of the neutrophils in the CPB group was (2675 +/- 479) and the fluorescence level of CD18 of the neutrophils was (1574 +/- 262), both significantly higher than those before heparinization and those of the sham group (all P < 0.05). Four hours after CPB, the MPO activity of lung tissue of the CPB group was (55.02 +/- 21.04 U/100 g wet tissue), significantly higher than those before heparinization and that of the sham group (both P < 0.05); the ratios of PaO2/FiO2 of the CPB group was (319 +/- 79), significantly lower than those before heparinization and that of the sham group (both P < 0.05). Transmission electron microscopic examination revealed tentacle protrusion on the neutrophil in the CPB group, while the neutrophils were intact in the sham group. Contrary to the increase of adhere function, the numbers of neutrophil with phagocytic function of the CPB group was 35% +/- 11%, significantly lower than that of the sham group (74% +/- 9%, P < 0.01) the number of bacteria phagocytized by neutrophils per ml blood of the CPB group was (1484 +/- 238 ), significantly lower than that of the sham group (3106 +/- 714). There were no differences in the accumulated points of MPO in neutrophils, release of MPO, and generation of oxygen free radical between these 2 groups. CONCLUSION: CPB causes neutrophil function disorder, including increase of adhesion function and reduction of phagocytic function.

Prognostic value of phagocytic activity of neutrophils and monocytes in sepsis. Correlation to CD64 and CD14 antigen expression.

The role of the phagocytic function of monocytes and neutrophils in sepsis has been poorly investigated. The present study evaluated the impact of the phagocytic activity of neutrophils and monocytes on the outcome of patients with severe sepsis. Thirty-one patients and 30 healthy individuals were enrolled in the study. The phagocytic activity of monocytes and neutrophils was evaluated during 24 h after admission and the results were correlated to the expression of CD64 on neutrophils and monocytes, CD14 antigen on monocytes, the Simplified Acute Physiology Score II and the patients' survival. A reduced phagocytic activity of neutrophils during the first 24 h after admission was a negative predictor for survival. Increased expression of CD64 antigen on polymorphonuclear cells (PMNs) and monocytes was favourably correlated to the patients' survival. In multivariate analysis the phagocytic activity of PMNs was the only independent predictor factor for survival. Patients with PMN phagocytic activity <37% had lower expression of CD64 on monocytes and PMNs and worse outcome, while those with phagocytic activity >37% had higher expression of CD64 on monocytes and PMNs and better outcome. Reduced phagocytic activity of neutrophils may represent a state of neutrophil inactivation similar to that previously described for monocytes during the compensatory anti-inflammatory response.