RATIONALE The reduction of neutrophil migration to the bacterial focus is associated with poor outcome in sepsis. OBJECTIVES The objective of this study was to identify soluble substances in the blood of septic mice that inhibit neutrophil migration. METHODS A pool of serum obtained from mice 2 hours after the induction of severe sepsis by cecal ligation and puncture inhibited the neutrophi...

A simple and reproducible method for the measurement of serum neutrophil clustering activity was developed. High clustering activity was found in 19/30 patients with active systemic lupus erythematosus (SLE), and 14/20 of those with severe disease flares. In contrast, 0/10 patients with quiescent SLE and 2/20 patients with rheumatoid arthritis had high neutrophil clustering activity. Particular...

We report a case of Wegener's granulomatosis (WG), with neutrophil accumulation in bronchoalveolar lavage fluid (BALF). Peripheral blood neutrophilia was present but the anti-neutrophil cytoplasmic antibody (ANCA) was negative. The serum and BALF levels of neutrophil-related cytokines, including interleukin (IL)-8, granulocyte colony-stimulating factor (G-CSF) and IL-1 beta, were increased, par...

The ability of highly purified human leukocytic pyrogen (LP) to stimulate neutrophil oxygen-dependent metabolism was studied. Human peripheral blood neutrophils exposed to leukocytic pyrogen in vitro demonstrated an increase in the percentage of neutrophils reducing nitroblue tetrazolium (NBT) dye and a marked stimulation of superoxide dismutase inhibitable reduction of ferricytochrome c. LP st...

Complement-mediated neutrophil activation appears to play an important role in ischemia-reperfusion (I/R) injury in a variety of tissues, including the heart, lung, and small bowel. The objective of this study was to determine whether inhibition of the alternative and classic complement cascades by administration of soluble complement receptor 1 (sCR1) prevents the increased neutrophil stiffnes...

Neutrophil infiltration constitutes the first step in wound healing, although their timely clearance by macrophage engulfment, or efferocytosis, is critical for efficient tissue repair. However, the specific mechanism for neutrophil clearance in wound healing remains undefined. Here we uncover a key role for CCN1 in neutrophil efferocytosis by acting as a bridging molecule that binds phosphatid...

To address the role of neutrophil elastase in pulmonary emphysema, neutrophil elastase-deficient mice and wild-type littermate controls were exposed to long-term cigarette smoke. Compared to wild-type littermates, mice that were deficient in neutrophil elastase were significantly protected (59%) from the development of emphysema. Previously, we demonstrated complete protection from emphysema in...

We have developed a mathematical model for the peripheral regulation of neutrophil production mediated by granulocyte colony-stimulating factor. We have used that model to show that the pattern of neutrophil oscillations in nine grey collies is consistent with the hypothesis that cyclical neutropenia is due to an oscillatory stem cell input to the neutrophil regulatory system, and not due to au...

BACKGROUND Inhaled antibiotics are commonly used in the treatment of cystic fibrosis lung disease. A previous study suggested neutrophil elastase activation by colistin in vitro. Here, we investigated direct effects of the commonly used antibiotics colistin and tobramycin on neutrophil elastase activity. METHODS Neutrophil elastase was measured spectrophotometrically. The antibiotics colistin...

Autophagy, an intracellular degradation and energy recycling mechanism, is emerging as an important regulator of immune responses. However, the role of autophagy in regulating neutrophil functions is not known. We investigated neutrophil biology using myeloid-specific autophagy-deficient mice and found that autophagy deficiency reduced neutrophil degranulation in vitro and in vivo. Mice with au...