Effect of steroid treatment on the migration behaviour of neutrophils in patients with early rheumatoid arthritis

Phagocyte dysfunction in polymyalgia rheumatica and other age-related, chronic, inflammatory conditions

This study was conducted to evaluate phagocyte function in patients with age-related chronic inflammatory conditions. It included 95 patients with PMR, 17 with GCA, 40 with EORA, and 25 age-matched HCs. Serum IL-8 was determined with a bead array. The chemotactic capacity, phagocytic ability, and oxidative burst activity of circulating leukocytes were determined with flow cytometry kits. Patients with active chronic inflammatory diseases showed a significant increase in circulating levels of IL-8 that remained elevated in patients with PMR or EORA, despite treatment. No correlation was found between circulating IL-8 and the migratory capacity of neutrophils. Neutrophils from patients with active EORA without stimulus and after fMLP stimuli showed a higher capacity to migrate than those of the HCs (P=0.033). The phagocytic activity of granulocytes in the patients with GCA was significantly higher than in the HCs and the patients with PMR or EORA (P<0.05). The percentage and MFI of phagocytes that produce ROIs when stimulated with Escherichia coli was significantly reduced in neutrophils and monocytes from the patients with age-restricted inflammatory conditions. We concluded that the effector functions of phagocytes, determined to be chemotaxis, phagocytosis, and oxidative burst, are deregulated in age-restricted inflammatory disorders and may have a pathogenic role.

Evaluation of the function of polymorphonuclear neutrophilic leukocytes in healthy dogs given a high dose of methylprednisolone sodium succinate

OBJECTIVE

To evaluate effects of a high dose of methylprednisolone sodium succinate (MPSS) on function of polymorphonuclear neutrophilic leukocytes (PMNs) in dogs.

ANIMALS

7 healthy male Beagles (body weight, 10.5 to 15 kg; age, 2 to 4 years).

PROCEDURES

All dogs were treated by IV administration of a high dose of MPSS (30 mg/kg). Additional doses of MPSS (15 mg/kg) were administered IV at 2 and 6 hours and then at 6-hour intervals until 48 hours after the initial dose. Blood samples were collected before and 1, 2, 4, 7, and 14 days after completion of the MPSS administrations and used for evaluation of PMN functions. Isolated PMNs were used for assessment of functions, such as adhesion, migration, phagocytosis, and oxidative burst.

RESULTS

On days 1, 2, and 4 after completion of MPSS administration, there was a decrease in PMN expression of adhesion markers such as CD11b and CD18. There was a decrease in the phagocytotic ability of PMNs on days 1, 2, and 7 after completion of MPSS administration, with a reduction in the oxidative burst of PMNs detected on day 7. No significant changes were identified for migration. All functional changes returned to their pretreatment values by 14 days after completion of MPSS treatment.

CONCLUSIONS AND CLINICAL RELEVANCE

Treatment with a high dose of MPSS suppressed PMN functions in dogs. Analysis of these results suggested that treatment with a high dose of MPSS can suppress some of the major functions of PMNs for at least 7 days.

Chimerical anti-TNF-alpha, infliximab, inhibits neutrophil chemotaxis and production of reactive oxygen species by blocking the priming effect of mononuclear cells on neutrophils

Clinical experience with anti-tumor necrosis factor alpha (anti-TNF-alpha) agents implies that these agents can cause a rapid onset amelioration of the symptoms and laboratory parameters in some inflammatory diseases. Precise explanation of this fast antiinflammatory action is not known. The aim of our study is to investigate the direct and indirect effects of anti-TNF agents on the chemotaxis and reactive oxygen species (ROS) production of neutrophils. For this purpose, isolated neutrophil cultures (INCs) and mixed leukocyte cultures were prepared from the venous blood of healthy subjects. Those cultures were separated to different groups according to the presence of anti-TNF or the stimulation of phytohemagglutinin (PHA). In this study, anti-TNF treatment did not change the migration ability of neutrophils in INCs. However, we established that chimerical anti-TNF-alpha, infliximab, inhibits neutrophil chemotaxis and production of ROS by blocking the priming effect of PHA-stimulated circulating mononuclear cells. These results may explain, at least partly, the rapid onset antiinflammatory actions of these agents observed in clinical practice.

Impaired blood polymorphonuclear leukocyte migration and infection risk in severe trauma

OBJECTIVES

We investigated the association of impaired blood polymorphonuclear leukocyte (PMN) migration with the incidence of bacterial infections in patients with severe trauma.

METHOD

Twenty-six intensive-care patients with different injury severity scores were enrolled in a prospective study. PMN migration was measured daily using 300 microl fresh whole blood in a membrane filter assay. Migration was evaluated in an automated image analyzer that recorded numbers and distribution of the immigrant PMNs within a filter. The relevant parameter was the percentage of PMNs that migrated from the blood samples into the filters upon f-Met-Leu-Phe stimulation.

RESULTS

Nine patients developed posttraumatic infections verified microbiologically. These patients showed a reduced PMN migratory capacity in comparison with the 17 patients without infections. A migrating portion of six per cent or less at least three days in succession preceded infections by one to 19 days and indicated infection in eight true positive versus three false positive cases, and 14 true negative versus one false negative case, i.e. specificity was 82.3% and sensitivity 88.8%, p=0.0008. Trauma severity had no influence on PMN migration.

CONCLUSIONS

Trauma patients with impaired PMN migration are at risk for bacterial infections. Whole-blood migration tests can define the infection risk and thus may be useful predictive markers for infections.

Chemotactic properties of ICAM-1 and PECAM-1 on neutrophil granulocytes in ulcerative colitis: effects of prednisolone and mesalazine

BACKGROUND

ICAM-1 seems to exhibit effects other than passive leucocyte/endothelial interaction.

AIM

To investigate the attracting properties of selected adhesion molecules, assessing the influence of the two major anti-inflammatory drugs in ulcerative colitis, prednisolone and mesalazine.

METHODS

Circulating neutrophils (11 ulcerative colitis, 15 controls) were assessed in microchemotaxis chambers by the leading front technique, using physiologically relevant concentrations of ICAM-1 (0.005-5000 pM), PECAM-1 (0.001-1000 nM), and P-selectin (0.01-100 nM). Neutrophils pre-incubated with prednisolone (10(-8)-10(-4) M) or mesalazine (0.65-10. 4 nM) were assessed towards ICAM-1.

RESULTS

Migration of neutrophils towards ICAM-1 showed a bell-shaped curve with a maximum at 5 pM (migration: 37.7 microm; P<0.001), whereas PECAM-1 attracted neutrophils equally in the range of 0.1-10 nM (25.0 microm; P<0.001). P-selectin had no cell-attracting effect. No differences were detected between cells from ulcerative colitis patients and controls. Pre-treatment with prednisolone decreased the cell attracting effect of ICAM-1 in a dose-dependent manner to 72% of the basal migration (P<0.001). Conversely, prednisolone showed a pro-chemokinetic effect by increasing the spontaneous locomotion of neutrophils by 40% (P<0.001).

CONCLUSIONS

Specific chemotactic properties were observed for ICAM-1 and PECAM-1. Prednisolone exhibited a dual effect in inhibiting the ICAM-1-mediated migration and stimulating the general locomotion of neutrophils.