Analysis of membrane antigens on neutrophils from patients with sepsis.

The aim of the present study was to assess changes of cell membrane antigens on neutrophils in septic patients. Expression levels of neutrophil membrane antigens were measured employing a FACS calibur flow cytometer with several fluorescence-labeled monoclonal antibodies. Expression levels of the CD14 antigen were higher in patients with sepsis than in healthy individuals. In particular, the expression levels of CD14 increased in patients complicated by septic shock. Expression levels of TLR-4 were higher in patients with sepsis or septic shock than in healthy individuals. Expression levels of CD11b and CD16 were lower in patients with sepsis or septic shock than in healthy individuals and were even lower in those complicated by septic shock. Expression levels of neutrophil membrane antigens in patients with sepsis markedly changed in the acute phase. However, these levels tended to return to those of healthy individuals in the convalescing phase. Analyses of the surface antigens on neutrophils strongly involved in biological defense or tissue injury are informative for understanding the pathology of sepsis and for conducting therapy targeting neutrophils in the future.

Downregulation of immunomodulator gene expression in LPS-stimulated human polymorphonuclear leukocytes by the proton pump inhibitor lansoprazole.

Lansoprazole (LPZ) has anti-inflammatory activity and repairs cells damaged by phagocytic cells. In the present study, we evaluated the effects of LPZ on gene expression, especially that of immunomodulator genes, in human polymorphonuclear leukocytes (PMNs) activated by lipopolysaccharide (LPS). Several concentrations of LPZ (final concentrations, 0-10 microg/ml) were added to the PMNs (1 x 10(6) cells/ml), which were stimulated with LPS (100 ng/ml) and incubated at 37 degrees C for 1 or 3 h. When LPS-stimulated PMNs were treated with LPZ at >or=5.0 microg/ml for 1 h, mRNA expression levels of CXCR1/2 and TNFalpha were suppressed in a dose-dependent manner. The gene expression level of CD14 was also downregulated by LPZ at >or=0.1 microg/ml, with expression suppressed to 50% by 10 microg/ml LPZ. However, LPZ at 0.01-5.0 microg/ml had no significant effect on the expression of TLR-4 or CD11b/CD18 mRNA. LPZ at 10 microg/ml downregulated the levels of these mRNAs to 80% and 50%, respectively. On the other hand, when the reaction period was extended to 3 h with the same conditions, all mRNA expression levels were downregulated by >or=0.01 microg/ml LPZ, in a dose-dependent manner. LPZ may suppress the biological functions of PMNs, such as chemotaxis and inflammatory chemokine production.

Destructive pulmonary embolism in a patient with community-acquired staphylococcal bacteremia.

We report a 17-year-old man with destructive pulmonary embolism caused by Staphylococcus aureus bacteremia. The patient was not immunocompromised and had neither underlying diseases nor risk factors, such as concomitant influenza viral infection, which exacerbate staphylococcal infections. The rapid and extensive progression of pulmonary involvement in all lung fields make this a rare case; there have been few reports in the literature describing a similar radiographic appearance in patients with community-acquired staphylococcal bacteremia. In-vitro studies did not demonstrate the production of enterotoxins or toxic shock syndrome toxin 1 (TSST-1) by the isolated strain, but genetic analysis detected Panton-Valentine leukocidine gene from the strain. Subsequent empyema with bilateral pneumothorax was prolonged because of superinfection with both methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. Optional surgical treatments, including thoracostomy and thoracopneumoplasty, finally improved his condition.