Sepsis remains one of the leading causes of death globally, in spite of advanced developments in intensive care and better understandings of pathophysiology related to sepsis. There is no special treatment or drug available for sepsis, currently. Under normal circumstances, neutrophil is a major player in acute infection control. However, during sepsis, the migration abilities and antimicrobial functions of neutrophils are impaired, resulting in a dysregulated immune response. Recent studies have indeed demonstrated that blocking or reversing neutrophil migration and impaired antibacterial function can improve the outcomes in septic animal models. This article systemically synthesized information regarding related factors and signaling involved in the functions of neutrophils in sepsis. This review also discussed the possibility that neutrophils be used as a marker for specific diagnosis and/or prediction of the outcomes of sepsis.
Animals ; Neutrophils/physiology* ; Chemotaxis ; Chemotaxis, Leukocyte ; Sepsis ; Cell Movement

Human polymorphonuclear leukocytes (PMN) migrate into tissues in response to chemoattractants, yet it is not known whether this process alters the functional capabilities of the PMN. Using recombinant human interleukin-8 (rHIL-8, 100 ng/ml) as a stimulus, we compared a population of PMN that migrated through a polyvinylpyrrolidone-coated polycarbonate filter containing 8.0 microns diameter pores with PMN stimulated in suspension. PMN were analyzed by flow cytometry according to functional and phenotypic criteria. CD11b/CD16 expression was unaltered by chemotaxis. In contrast, chemotaxis enhanced phagocytosis of E. coli, independent of opsonization with IgG. Similarly, chemotaxis increased baseline hydrogen peroxide production. We conclude that the chemotactic motion of PMN "primes" the cell for increased oxidative burst activity and augments the ability of PMN to ingest bacteria. This increased functional capability is distinct from rHIL-8 stimulation and appears to be independent of complement-and Fc-receptor expression.
Antigens, CD/analysis ; Chemotaxis, Leukocyte/*physiology ; Escherichia coli/immunology ; Humans ; Neutrophils/physiology ; Phagocytosis/physiology ; Phenotype ; Receptors, IgG/analysis ; Respiratory Burst/physiology

The functional immaturity of PMNs is one of the major causes of overwhelming sepsis in newborns. In this study, we observed functions and surface markers of PMNs to investigate what causes the functional immaturity of PMNs in newborns. As results, the percentage of EA rosette forming PMNs (58.5 +/- 15.5%) and the chemotactic movement (0.14 +/- 0.09 mm) of cord blood PMNs were significantly lower than those of adult peripheral blood PMNs (70.8 +/- 9.9%, 0.60 +/- 0.34 mm). Cord blood PMNs showed decreased glass adherence and ADCC activity. The expression of Fc gamma RII or Fc gamma RIII was a little lower than those of adult peripheral blood PMNs, but the expression of Fc gamma RI (43.1 +/- 26.8%) was significantly higher than that of adult peripheral blood PMNs (3.2 +/- 1.8%). There was a significant difference in LFA-1 expression between EA rosette forming PMNs (92.9 +/- 9.1%) and EA rosette non-forming PMNs (25.6 +/- 22.6%). From these results, it is assumed that neonatal PMNs may consist of heterogeneous populations. And the relatively high percentage of EA rosette non-forming PMNs which express a low level of LFA-1 may be responsible for the functional immaturity of cord blood PMNs.
Antibody-Dependent Cell Cytotoxicity ; Cell Adhesion ; Chemotaxis, Leukocyte ; Fetal Blood/*cytology ; Human ; Lymphocyte Function-Associated Antigen-1/*physiology ; Neutrophils/*physiology ; Receptors, IgG/*physiology ; Rosette Formation

OBJECTIVETo study the effects of very late antigen(VLA) antagonist BIO-1211 on eosinophil chemotaxis, recruitment and mediator release.

METHODSEosinophil chemotaxis was induced by platelet activating factor(PAF) in vitro and eosinophil recruitment and release were determined in vivo.

RESULTVLA antagonist BIO-1211 inhibited eosinophil chemotaxis induced by PAF. The inhibitory rates at 4x10(-11), 4x10(-10), 4x10(-9) mol x L(-1) were 24.9%, 29.9%, and 31.3%, respectively. Pretreatment by BIO-1211 1, 3 and 10 mg x kg(-1) intraperitoneally inhibited the recruitment of eosinophils in PAF in the rat induced by Sephadex in a dose dependent manner. Inhibitory rates were 60.3%, 68.9%, and 72.9%(P<0.05), respectively. BIO-1211 did not inhibit eosinophil peroxidase(EPO) release from eosinophils.

CONCLUSIONBIO-1211 inhibits eosinophil chemotaxis and recruitment, alleviates local inflammation, and may represent a new type of drug for allergic diseases.

Animals ; Cell Movement ; drug effects ; Chemotaxis, Leukocyte ; drug effects ; Dose-Response Relationship, Drug ; Eosinophil Peroxidase ; Eosinophils ; drug effects ; physiology ; Integrin alpha4beta1 ; antagonists & inhibitors ; physiology ; Male ; Oligopeptides ; pharmacology ; Peroxidases ; secretion ; Platelet Activating Factor ; pharmacology ; Rats ; Rats, Sprague-Dawley

In order to study whether the endothelial cells (ECs) with lipid peroxidation induced by diamide can express and secrete macrophage inflammatory protein 1 alpha (MIP-1 alpha), the expression of MIP-1 alpha protein in the cells was detected by cell enzyme-linked immunosorbent assay (ELISA) and that of MIP-1 alpha mRNA was determined by cell in situ hybridization and nuclease S1 protection assay after the ECs were exposed to different concentrations of diamide for 4 h. The chemotactic activity of MIP-1 alpha was tested by micropore filter method using modified Boyden chambers. Cell ELISA showed that the expression of MIP-1 alpha protein in endothelial cells exposed to 1 mumol/L, 5 mumol/L and 10 mumol/L diamide was 1.9-fold, 2.3-fold and 1.7-fold respectively as much as that in the control cells, which was statistically significant by analysis of variance. In situ hybridization revealed that the mRNA expression of ECs treated with 1 mumol/L, 5 mumol/L and 10 mumol/L diamide was 1.3-fold, 3.0-fold and 1.7-fold as much as that in the control group, which had statistical significance (F = 188.93, P < 0.01). The mRNA expression in 5 mumol/L dimide treated ECs, measured by nuclease S1 protection assay, was 3.4-fold as much as that in the control group (t = 8.70, P < 0.05). Chemotactic response(99.50 +/- 4.31 microns) to the culture medium conditioned by 5 mumol/L diamide treated ECs, which was stronger than that(66.47 +/- 3.25 microns) conditioned by the ECs (F = 404.31, P < 0.05), was significantly decreased (F = 192.25, P < 0.05) after adding MIP-1 alpha antibody. It suggests that diamide, a lipid peroxidation inducer, could stimulate ECs to produce high level of MIP-1 alpha, and might play an important role in atherogenesis by promoting the migration of peripheral blood monocytes into arterial intima.
Cells, Cultured ; Chemokine CCL3 ; Chemokine CCL4 ; Chemotaxis, Leukocyte ; physiology ; Diamide ; pharmacology ; Endothelium, Vascular ; cytology ; metabolism ; Humans ; Lipid Peroxidation ; Macrophage Inflammatory Proteins ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Sulfhydryl Reagents ; pharmacology ; Umbilical Veins ; cytology

AIMTo study the inhibitory effect of ginkgolide B (BN52021) on the PAF induced changes of chemotaxis of murine peritoneal macrophages and the related polymerization of F-actin.

METHODSChemotaxis assays were performed using a modified 48-well Boyden chamber. Actin polymerization of murine peritoneal macrophages was analyzed by flow cytometry using a specific fluorescent stain.

RESULTSPeritoneal macrophages significantly migrated toward platelet-activating factor (PAF) through a micropore filter; however, in the presence of PAF receptor antagonist BN52021 (0.01 nmol x L(-1) -0.1 micromol x L(-1)), the migration was significantly inhibited. Moreover, BN52021 inhibited the actin polymerization of murine peritoneal macrophages induced by PAF in the presence of Ca2+, but not in Ca2+ -free medium.

CONCLUSIONThe results suggested that preventing polymerization of F-actin may be a pathway by BN52021 to inhibit the chemotaxis of macrophages, and this effect seems to be Ca2+ dependent. The data further indicated that inhibition of PAF induced macrophage chemotaxis is an important mechanism underlying the anti-inflammatory action of BN52021.

Actins ; metabolism ; Animals ; Chemotaxis, Leukocyte ; drug effects ; Diterpenes ; isolation & purification ; pharmacology ; Ginkgo biloba ; chemistry ; Ginkgolides ; Lactones ; isolation & purification ; pharmacology ; Macrophages, Peritoneal ; metabolism ; physiology ; Mice ; Mice, Inbred C57BL ; Plants, Medicinal ; chemistry ; Platelet Activating Factor ; antagonists & inhibitors

OBJECTIVETo investigate the effects of Musk glucoprotein on chemotaxis of Polymorphonuclear leukocytes(PMN).

METHODThe chemotaxis of PMN in abdominal cavity in rat induced by carboxymethyl cellulose(CMC) was used as an in vivo animal model and in in vitro it was evaluated by Boyden chamber. The concentration of cytosolic free Ca2+ was quantitated with the fluorescent Ca2+ indicator Fura-2.

RESULTThe water extract of Musk at dose of 5, 20, 80 mg.kg-1 (s.c.) significantly inhibited the chemotaxis of PMN in rat; Musk-1 at concentration of 1-100 micrograms.mL-1 can significantly inhibit the chemotaxis of rabbit PMN in vitro; Musk-1 at concentration of 1-100 micrograms.mL-1 can significantly inhibit the increase of cytosolic Ca2+ concentration in PMN of rat.

CONCLUSIONPart of mechanisms underlying antiinflammatory action of Musk is to inhibit the chemotaxis of PMN.

Animals ; Anti-Inflammatory Agents, Non-Steroidal ; pharmacology ; Calcium ; metabolism ; Chemotaxis, Leukocyte ; drug effects ; Fatty Acids, Monounsaturated ; chemistry ; pharmacology ; Female ; Glycoproteins ; isolation & purification ; pharmacology ; Male ; Materia Medica ; isolation & purification ; pharmacology ; Neutrophils ; metabolism ; physiology ; Rabbits ; Rats ; Rats, Wistar

Cells, Cultured ; Chemokine CCL4 ; Chemotaxis, Leukocyte ; drug effects ; Endothelial Cells ; cytology ; metabolism ; Homocysteine ; pharmacology ; Humans ; Macrophage Inflammatory Proteins ; biosynthesis ; genetics ; Monocytes ; physiology ; RNA, Messenger ; biosynthesis ; genetics ; Umbilical Veins ; cytology

In order to study whether the endothelial cells (ECs) with lipid peroxidation induced by diamide can express and secrete macrophage inflammatory protein 1 alpha (MIP-1 alpha), the expression of MIP-1 alpha protein in the cells was detected by cell enzyme-linked immunosorbent assay (ELISA) and that of MIP-1 alpha mRNA was determined by cell in situ hybridization and nuclease S1 protection assay after the ECs were exposed to different concentrations of diamide for 4 h. The chemotactic activity of MIP-1 alpha was tested by micropore filter method using modified Boyden chambers. Cell ELISA showed that the expression of MIP-1 alpha protein in endothelial cells exposed to 1 mumol/L, 5 mumol/L and 10 mumol/L diamide was 1.9-fold, 2.3-fold and 1.7-fold respectively as much as that in the control cells, which was statistically significant by analysis of variance. In situ hybridization revealed that the mRNA expression of ECs treated with 1 mumol/L, 5 mumol/L and 10 mumol/L diamide was 1.3-fold, 3.0-fold and 1.7-fold as much as that in the control group, which had statistical significance (F = 188.93, P < 0.01). The mRNA expression in 5 mumol/L dimide treated ECs, measured by nuclease S1 protection assay, was 3.4-fold as much as that in the control group (t = 8.70, P < 0.05). Chemotactic response(99.50 +/- 4.31 microns) to the culture medium conditioned by 5 mumol/L diamide treated ECs, which was stronger than that(66.47 +/- 3.25 microns) conditioned by the ECs (F = 404.31, P < 0.05), was significantly decreased (F = 192.25, P < 0.05) after adding MIP-1 alpha antibody. It suggests that diamide, a lipid peroxidation inducer, could stimulate ECs to produce high level of MIP-1 alpha, and might play an important role in atherogenesis by promoting the migration of peripheral blood monocytes into arterial intima.
Cells, Cultured ; Chemotaxis, Leukocyte/physiology ; Diamide/*pharmacology ; Endothelium, Vascular/cytology ; Endothelium, Vascular/*metabolism ; Lipid Peroxidation ; Macrophage Inflammatory Protein-1/*biosynthesis ; Macrophage Inflammatory Protein-1/genetics ; RNA, Messenger/biosynthesis ; RNA, Messenger/genetics ; Sulfhydryl Reagents/pharmacology ; Umbilical Veins/cytology

In this study, we observed that lysophosphatidylglycerol (LPG) completely inhibited a formyl peptide receptor like-1 (FPRL1) agonist (MMK-1)-stimulated chemotactic migration in human phagocytes, such as neutrophils and monocytes. LPG also dramatically inhibited IL-1beta production by another FPRL1 agonist serum amyloid A (SAA) in human phagocytes. However, LPG itself induced intracellular calcium increase and superoxide anion production in human phagocytes. Keeping in mind that phagocytes migration and IL-1beta production by FPRL1 are important for the induction of inflammatory response, our data suggest that LPG can be regarded as a useful material for the modulation of inflammatory response induced by FPRL1 activation.
Chemotaxis, Leukocyte/*drug effects ; Humans ; Interleukin-1beta/*biosynthesis ; Lysophospholipids/*pharmacology ; Monocytes/drug effects/immunology/metabolism/physiology ; Neutrophils/drug effects/immunology/metabolism/physiology ; Peptides/metabolism/pharmacology ; *Phagocytes/drug effects/immunology/metabolism/physiology ; Receptors, Formyl Peptide/*metabolism ; Receptors, Lipoxin/*metabolism ; Serum Amyloid A Protein/metabolism/pharmacology