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Introduction The inflammatory marker patterns of community-acquired Pneumonia (CAP) induced by different microorganisms in adult patients remained unclear. Objectives We aim to explore the inflammatory marker patterns of adult CAP patients induced by different pathogens. Methods Adult CAP patients with definite etiologies were enrolled from September 2010 to June 2012. They were divided into three groups according to the causative pathogens: typical bacteria, Mycoplasma pneumoniae (MP), and viruses. Twenty-seven cytokines and bactericidal/permeability-increasing protein (BPI) levels of serum collected within 7 days onset in these groups were compared. Results One hundred twenty-four cases were enrolled for serum detection and analysis, including 10 typical bacterial pneumonia patients, 56 cases with MP pneumonia and 58 with viral pneumonia. Three kinds (PDGF-BB, IP-10, RANTES) of 27 cytokines and BPI levels were significantly elevated in patients with acute pneumonia than healthy controls. Distinct inflammatory marker patterns were released by different pathogens: typical bacterial pneumonia patients had highest levels of BPI, IL-6, IL-8, IL-1rα; while patients caused by MP presented higher levels of PDGF-BB, IL-17A, G-CSF than those caused by viruses. Rhinovirus owned a higher inflammatory response level than the other viruses. The area under the curve (AUC) of PDGF-BB to differentiate MP and virus infection was biggest, which was 0.708. Conclusion Distinct inflammatory marker patterns were released by different pathogens during acute pneumonia. Significantly increased level of PDGF-BB was observed in acute pneumonia for the first time. It showed a better ability to differentiate MP and virus infection.

Background Antineutrophil cytoplasmic autoantibodies against neutrophil granule bactericidal/permeability-increasing protein (BPI-ANCA) has been found in many inflammatory diseases, such as COPD, which can reduce the killing effect of BPI on Gram-negative bacteria. This study was aimed to assess the clinical significance of BPI-ANCA detecting in COPD patients with Pseudomonas aeruginosa (P aeruginosa) colonization. Methods A total of 216 COPD patients with lung P aeruginosa colonization, 244 patients with P aeruginosa infection from June 2015 to June 2018, and 100 healthy individuals were included. Serum BPI-ANCA, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 and IL-1β levels were detected by ELISA, and the lung function of the patients was measured at stable clinical stages. Patients with COPD were grouped according to BPI-ANCA detection and GOLD criteria, and serum TNF-α, IL-6, and IL-1β levels and indices reflecting lung function were compared and analyzed between groups. Results Positive rate of BPI-ANCA in COPD patients with P aeruginosa colonization was 48.15%; and compared with BPI-ANCA(-) group, FEV1 %pred and FEV1 /FVC(%) in BPI-ANCA(+) patients were significantly decreased, while TNF-α, IL-6, and IL-1β levels were elevated. There were 31.73% and 36.54% BPI-ANCA(+) patients with severe and very severe airflow limitation, respectively, which was significantly higher than that in the BPI-ANCA(-) group. FEV1 %pred and FEV1 /FVC(%) were negatively correlated with TNF-α, IL-6, IL-1β, and NEU%. C-reactive protein (CRP) was negatively correlated with FEV1 %pred, yet not significantly correlated with FEV1 /FVC(%). Conclusion BPI-ANCA positivity is associated with inflammatory status in COPD patients with pulmonary P aeruginosa colonization and can be used as a potential biomarker assessing disease severity.

Objectives We investigated the association between autoantibodies against non-myeloperoxidase (MPO) neutrophil granule antigens and activity of Behcet's disease (BD). Methods We consecutively enrolled 51 BD patients. We assessed clinical data and BD activity using patients' index scores from the Behcet's Disease Current Activity Form and we performed tests for antibodies against proteinase 3 (PR3), MPO, bactericidal permeability increasing protein (BPI), cathepsin G, elastase, lactoferrin and lysozyme. Results The median patient index score was 2.0, and 56.9% of patients had active BD. In multivariate analysis of variables with significant correlations, only anti-lysozyme showed a significant correlation with BD activity (P = 0.002). In multivariate logistic regression analyses of variables, when patients were classified into groups according to the optimal cutoff levels of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and anti-lysozyme (ESR > 42.5 mm/h, CRP > 1.35 mg/L and anti-lysozyme > 2.95 IU/mL), the variable with independent predictive value was anti-lysozyme (odds ratio 8.384, P = 0.015). Conclusion Anti-lysozyme was significantly correlated with disease activity score and it was the only independent value to predict active disease in patients with BD. Furthermore, patients having anti-lysozyme levels ≥ 2.95 IU/mL had a significantly higher risk of having active BD than those who did not.

Vibrio splendidus, strain LGP32, is an oyster pathogen associated with the summer mortalities affecting the production of Crassostrea gigas oysters worldwide. Vibrio splendidus LGP32 was shown to resist to up to 10 µM Cg-Def defensin and Cg-BPI bactericidal permeability increasing protein, two antimicrobial peptides/proteins (AMPs) involved in C. gigas immunity. The resistance to both oyster Cg-Def and Cg-BPI and standard AMPs (polymyxin B, protegrin, human BPI) was dependent on the ompU gene. Indeed, upon ompU inactivation, minimal bactericidal concentrations decreased by up to fourfold. AMP resistance was restored upon ectopic expression of ompU. The susceptibility of bacterial membranes to AMP-induced damages was independent of the ompU-mediated AMP resistance. Besides its role in AMP resistance, ompU proved to be essential for the adherence of V. splendidus LGP32 to fibronectin. Interestingly, in vivo, ompU was identified as a major determinant of V. splendidus pathogenicity in oyster experimental infections. Indeed, the V. splendidus-induced oyster mortalities dropped from 56% to 11% upon ompU mutation (Kaplan-Meier survival curves, P < 0.01). Moreover, in co-infection assays, the ompU mutant was out competed by the wild-type strain with competitive indexes in the range of 0.1-0.2. From this study, ompU is required for virulence of V. splendidus. Contributing to AMP resistance, conferring adhesive properties to V. splendidus, and being essential for in vivo fitness, the OmpU porin appears as an essential effector of the C. gigas/V. splendidus interaction.

Cholesteryl ester transfer protein (CETP) plays an important role in plasma lipoprotein metabolism through its ability to transfer cholesteryl ester, triglyceride, and phospholipid between lipoproteins. CETP is a member of a gene family that also includes bactericidal/permeability-increasing protein (BPI). The crystal structure of BPI shows it to be composed of two domains that share a similar structural fold that includes an apolar ligand-binding pocket. As structurally important residues are conserved between BPI and CETP, it is thought that CETP and BPI may have a similar overall conformation. We have previously proposed a model of CETP structure based on the binding characteristics of anti-CETP monoclonal antibodies (mAbs). We now present a refined epitope map of CETP that has been adapted to a structural model of CETP that uses the atomic coordinates of BPI. Four epitopes composed of CETP residues 215-219, 219-223, 223-227, and 444-450, respectively, are predicted to be situated on the external surface of the central beta-sheet and a fifth epitope (residues 225-258) on an extended linker that connects the two domains of the molecule. Three other epitopes, residues 317-331, 360-366, and 393-410, would form part of the putative carboxy-terminal beta-barrel. The ability of the corresponding mAbs to compete for binding to CETP is consistent with the proximity of the respective epitopes in the model. These results thus provide experimental evidence that is consistent with CETP and BPI having similar surface topologies.

To examine the presence of bactericidal/permeability-increasing protein (BPI) in skin, which is an antibacterial protein, has cytotoxicity toward Gram-negative bacteria, and may have an important role against bacterial infection in the skin, immunohistochemical and biochemical analyses were performed. Anti-BPI/KLH Ab reacted with the cytoplasm of the inner root sheath cells of both human and rat hair follicles by immunohistochemical examination. A protein band in 10-M alkaline urea extracts of human scalp skin or 7-day-old rat skin reacted with an antibody against BPI conjugated with KLH (anti-BPI/KLH Ab). Purified skin BPI (sBPI) from rat was a single protein spot and reacted with both anti-BPI/KLH Ab and a commercially available monoclonal antibody against BPI (anti-BPI MoAb). Moreover, sBPI possessed inhibitory activity against LPS. Bactericidal/permeability-increasing protein mRNA was expressed not only in leukocytes but also in human scalp skin and cultured keratinocytes. These findings suggest that sBPI could exist in the inner root sheath cells of human and rat hair follicles, and might play a role as a barrier against anaerobic bacteria in the isthmus of hair follicles.

Background Surgery induces a process of wound healing, which has immunological and angiogenic aspects. Bactericidal/permeability-increasing protein (BPI) is found in azurophilic granules of human neutrophils, which is bactericidal and neutralizes lipo-polysaccharide (LPS). This may reduce postoperative infectious complications. In addition, BPI has been shown to be an inhibitor of angiogenesis. Methods A total of 18 patients with metastasized colorectal carcinoma to the liver were double blind randomized. The levels of the pro-angiogenic factors interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) and the angiogenesis inhibitor endostatin were investigated after liver surgery with perioperative administration of either rBPI21 or placebo. Results The highest IL-6 levels were found during the first 24 hr and reached peak levels already at 2 hr postoperatively in both groups. In both groups VEGF levels decreased sharply in the postoperative hours, returning to baseline levels in the days afterwards. In both groups, an immediate decrease in endostatin levels was observed which remained significantly low. RBPI21 transiently influenced IL-6 and VEGF. Conclusions RBPI21 only marginally affected IL-6 and VEGF levels. Surgery per se induced an immediate immune response (IL-6) and an immediate angiogenic response, reflected in an initial VEGF decrease and a longer lasting decrease of endostatin. These findings demonstrate the dynamics of tissue responses in the first phase of wound healing. J. Surg. Oncol. 2003;84:137–142. © 2003 Wiley-Liss, Inc.

Background: Endotoxin (lipopolysaccharide, LPS) up-regulates inducible nitric oxide synthase (iNOS) in blood vessels during septic shock. This promotes the production of nitric oxide (NO), leading to dilation of the vessels. The aim of the study was to investigate the effects of the LPS-binding endogenous antibiotic bactericidal/permeability-increasing protein (BPI) on the action of LPS on the blood vessels wall and to identify possible influence on underlying NO-related mechanisms. Methods: Isolated segments of rat thoracic aorta and cultured primary smooth muscle cells were incubated for 5–48 h in the presence of the following combinations of compounds: (a) LPS; (b) interleukin-1b (IL-1b); (c) BPI; (d) BPI π LPS; (e) BPI π IL-1b or (f) neither BPI, LPS nor IL-1b (control). After incubation of intact segments, we measured smooth muscle contraction in response to phenylephrine and accumulation of the NO end products nitrate and nitrite in surrounding medium. Western blot was used to assess the levels of inducible nitric oxide synthase (iNOS) in cultured cells.

Prestorage leucocyte reduction of red cell components prevents release of bactericidal permeability increasing protein and defensins. Fransen EJ, Rombout-Sestrienkova E, van Pampus EC, Buurman WA, Reutelingsperger CP, Maessen JG. Department of Cardiothoracic Surgery, University Hospital Maastricht, P. Debyelaan 25, PO Box 5800, 6202 AZ Maastricht, the Netherlands. efr@scpc.azm.nl BACKGROUND AND OBJECTIVES: In this study we examined whether prestorage leucocyte reduction prevents the accumulation of bioreactive substances in red cell units. MATERIALS AND METHODS: Measurements were performed in the supernatants of buffy-coat-depleted (standard red cells) and leucocyte-reduced (filtered red cells) red cell units. The effect of storage was evaluated by taking repetitive samples up to 35 days after donation. We determined the concentrations of polymorphonuclear neutrophil (PMN)-derived bactericidal permeability increasing protein (BPI), defensins and annexin A5. In addition, leucocyte counts (using nageotte chamber) were performed on days 0 and 35. RESULTS: During storage, the concentrations of BPI, defensins and annexin A5 in standard red cells gradually increased. However, in the filtered red cells BPI and defensins were found in only a few samples, whereas the annexin A5 concentration in these units did not change during storage. Haemolysis data in both types of red cell components were similar at all time-points, except prestorage. Significant correlations were found between the release of BPI, defensins and annexin A5 into red cell units and the loss of leucocytes during storage. CONCLUSIONS: PMNs lose their membrane integrity during cold storage and release their contents into red cell components. Prestorage leucocyte reduction of red cell components prevents the accumulation of BPI, defensins and annexin A5.

The neutrophil bactericidal/permeability-increasing protein (BPI) has both bactericidal and lipopolysaccharide-neutralizing activities. The present study suggests that BPI also plays an important role in phagocytosis of Escherichia coli by neutrophils through promotion of complement activation on the bacterial surface. Flow cytometric analysis indicated that fluorescein-labelled E. coli treated with BPI were phagocytosed in the presence of serum at two- to five-fold higher levels than phagocytosis of the bacteria without the treatment. In contrast, phagocytosis of the fluoresceined bacteria with or without treatment by BPI did not occur at all in the absence of serum. The phagocytosis stimulated by BPI and serum was dose-dependent. The effect of BPI on phagocytosis in the presence of serum was not observed on Gram-positive bacteria (Staphylococcus aureus). Interestingly, the complement C3b/iC3b fragments were deposited onto the bacterial surface also as a function of the BPI concentration under conditions similar to those for phagocytosis. Furthermore, the BPI-promoted phagocytosis was blocked completely by anti-C3 F(ab')(2) and partially by anti-complement receptor (CR) type 1 and/or anti-CR type 3. These findings suggest that BPI accelerates complement activation to opsonize bacteria with complement-derived fragments, leading to stimulation of phagocytosis by neutrophils via CR(s).

We evaluated the ability of an antimicrobial and endotoxin-neutralizing agent, the recombinant amino terminal fragment of bactericidal permeability-increasing protein (rBPI21), to decrease plasma endotoxin concentration and severity of clinical signs of canine parvovirus and to improve survival. This randomized, double-blinded, placebo-controlled clinical trial included 40 client-owned dogs and 9 normal puppies from a closed research colony. Dogs weighing >5 kg (11 lb) with fecal antigen-confirmed parvovirus and clinical signs of vomiting and diarrhea were randomly assigned to receive placebo or rBPI21 infusion over 6 hours. Plasma endotoxin concentration was measured at 0, 3, and 6 hours of infusion. Owners chose continued medical care with either the Veterinary Hospital of the University of Pennsylvania Internal Medicine Service or a local veterinarian. Telephone follow-up was conducted at 14 days. Surviving dogs were reevaluated at >30 days (recovered group), at which time plasma samples for measurement of endotoxin concentration were obtained. Plasma endotoxin concentrations were significantly higher in dogs with parvovirus than in normal or recovered dogs. Despite 90% survival, the rBPI21 treatment did not have a significant effect on outcome, duration of hospitalization, or plasma endotoxin concentrations. Treatment in a tertiary care hospital, however, significantly improved survival but resulted in a significantly increased duration of hospitalization. Endotoxemia occurs in dogs with parvovirus enteritis, but rBPI21 is not associated with improved survival.

Background/Aims: Major liver resection results in a high morbidity and mortality, and endotoxin plays a role in post-resection hepatic failure. Severe hepatic failure as seen in hepatitis and cirrhosis may be accompanied by hepatic encephalopathy and is characterized by a typical plasma amino acid pattern reflected by a decreased Fischer ratio. This study was performed to evaluate the plasma amino acid pattern in patients undergoing major liver surgery receiving placebo or the endotoxin-neutralizing agent bactericidal/permeability-increasing protein (rBPI(21)) Patients and methods: Forty-eight patients were randomized in this phase II, dose escalation, multicenter trial. Plasma amino acid profiles were determined preoperatively, and on the first (day 1) and third (day 3) postoperative day. Results. In the placebo group the Fischer ratio decreased significantly on both postoperative days. Administration of rBPI(21) also resulted in a decreased Fischer ratio on day 1, but not on day 3. Highly elevated alanine plasma levels were observed on day 1 in placebo-treated patients, whereas rBPI21 prevented this elevation. Plasma alanine levels on day 1 correlated with the duration of post-resection hepatic failure. Conclusions: Major liver resection results in a decreased Fischer ratio and a rise in plasma alanine levels. Plasma levels of alanine on the first postoperative day correlated with the duration of the post-resection hepatic failure. rBPI(21) improved the Fischer ratio and prevented the rise of plasma alanine levels.

Phase I pharmacokinetic and safety studies were conducted in healthy volunteers with rBPI21, a recombinant protein derived from the amino terminal domain of human bactericidal/permeability-increasing protein. rBPI21 was administered as a 30-minute infusion at doses of 0.25 to 4 mg/kg or as a 24- to 48-hour infusion at doses of 2 to 8 mg/kg. For the 30-minute infusions, the clearance of rBPI21 decreased with increasing dose from 8.4 mL/min/kg at 0.25 mg/kg to 3.3 mL/min/kg at 4 mg/kg. For rBPI21 infused over 24 to 48 hours the clearance was 10 to 11 mL/min/kg. The concentration-time profile of rBPI21 was well described by a three-compartmental model with parallel first-order and Michaelis-Menten (saturable) elimination. This model for the clearance of rBPI21 has been useful in estimating starting doses for therapeutic clinical trials.

Lipopolysaccharides (LPS, endotoxin) stimulate mononuclear cells to release cytokines which initiate endotoxic effects. Interaction of LPS at low concentrations with target cells is CD14-independent whereas at high LPS concentrations it is CD14-independent. Here, we demonstrate by resonance energy transfer (RET) technique that nonspecific, CD14-independent intercalation of LPS into membrane systems can be mediated by lipopolysaccharide-binding protein (LBP). It is proposed that in this pathway, LBP breaks down LPS aggregates, transports the smaller units to and inserts them into the phospholipid cell matrix. We furthermore show that LBP also mediates the intercalation of other negatively charged amphiphilic molecules. We propose a model explaining CD14-independent cell activation at high endotoxin concentrations.

This study was performed to clarify the mechanisms underlying post-resection changes in liver cell proliferation and metabolism. To assess the role of gut-derived endotoxaemia and endogenous cytokines in these changes, the effects of peri-operative treatment with either the lipopolysaccharide-neutralizing bactericidal/permeability-increasing protein or interleukin-1 receptor antagonist were investigated at 24 h after two-thirds hepatectomy in rats. Peri-operative treatment with either agent caused enhanced expression of proliferating cell nuclear antigen (PCNA) and reduced lipid accumulation. Activity of the hexose monophosphate shunt was significantly decreased after partial hepatectomy and restored by interleukin-1 receptor antagonist only. After partial hepatectomy, bile canalicular alkaline phosphatase activity was significantly increased in pericentral zones and redistributed to both bile canalicular and sinusoidal membranes of hepatocytes. These effects were not significantly influenced by either treatment. It is concluded that endotoxin restricts liver cell proliferation and leads to lipid accumulation following partial hepatectomy, and that interleukin-1 is a principal mediator in these processes. Furthermore, interleukin-1 mediates a repression of the pentose phosphate pathway. These changes may be of significance with respect to liver function, at least in the early phase after partial hepatectomy.