Defective production of interleukin-1 beta in patients with type 2 diabetes mellitus: Restoration by proper glycemic control.

The underlying immune defect of susceptibility in diabetes mellitus type 2 to infections remains unknown. The qualitative changes in cytokine biosynthesis by circulating mononuclear cells (PBMCs) and its modulation by glycemic control were investigated. PBMCs were isolated from 39 patients and 25 controls. They were stimulated with purified ligands and heat-killed bacteria in the absence/presence of glucose and NLPR3 inflammasome ligands. Experiments were repeated after 3 and 6months. Cytokine production was measured in cell supernatants; pro-interleukin(IL)-1 ß was measured in cell lysates. Gene expression of IL-1ß and activity of caspase-1 were measured as well. Adequate release of interleukin (IL)-1ß was found in 42.9% of patients compared to 90% of controls (p: 0.0001). This was related with down-regulation of the NLRP3 inflammasome since gene expression of IL-1ß remained unaltered whereas both the ratio of IL-1ß to the intracellular pro-IL-1ß and the activity of caspase-1 was lower in patients than controls. Addition of glucose did not modify defective IL-1ß production. IL-6 production was increased after stimulation with Pam3Cys, phytohemagglutinin and C. albicans. After proper glycemic control, release of IL-1ß was increased and of IL-6 decreased; cells of patients with improved glycemic control responded better to LPS stimulation under increased concentrations of glucose. It is concluded that diabetes type 2 is characterized by defective production of IL-1ß from circulating monocytes due to impaired activation of the NLRP3 inflammasome and increased production of the anti-inflammatory IL-6. Defects are restored with proper glycemic control.

Activation of NLRP3 Inflammasome in Inflammatory Bowel Disease: Differences Between Crohn's Disease and Ulcerative Colitis.

BACKGROUND: NLRP3 inflammasome is a multimolecular cytosol complex that, when activated, contributes to the cleavage of pro-interleukin (IL)-1ß to IL-1ß. AIMS: To investigate NLRP3 inflammasome activation in inflammatory bowel disease. METHODS: Peripheral blood mononuclear cells from Crohn's disease (CD), ulcerative colitis (UC) patients and controls were stimulated with LPS in the absence or presence of MSU. After incubation, concentrations of IL-1ß, IL-6, and TNFα were measured in cell supernatants and concentration of pro-IL-1ß was measured in cell lysates. NLRP3 activation was defined as more than 30% increase in IL-1ß production after MSU addition. In separate experiments, PBMCs were lysed for RNA isolation transcripts of IL-1ß, TNFα, NLRP3, and CASP1 were measured by RT-PCR. DNA was isolated from CD patients for ATG16L1 gene genotyping. RESULTS: NLRP3 inflammasome was activated in 60% of CD patients compared to 28.6% of controls (p = 0.042); no significant difference was detected between UC and controls. Among UC patients, NLRP3 activation was associated (p = 0.008) with long-standing disease (>1.5 years). IL-1ß levels were significantly higher in CD patents in comparison with controls (p = 0.032). No difference was detected in the levels of IL-6, TNFα, pro-IL-1ß and in the numbers IL-1ß, TNFα, NLRP3, and CASP1 transcripts among groups. IL-1ß production was similar between carriers of wild-type and of SNP alleles of the rs2241880. CONCLUSIONS: NLRP3 inflammasome is activated in CD patients and in UC patients with long-standing disease.

Interactions of Klebsiella pneumoniae with the innate immune system vary in relation to clone and resistance phenotype.

Apart from inadequate antimicrobial treatment, specific virulence factors contribute to the high attributable mortality of infections caused by multidrug-resistant (MDR) Klebsiella pneumoniae. We explored the roles of MDR and clones as virulence determinants of K. pneumoniae and their interaction with innate immunity. Twenty isolates were studied and characterized by resistance phenotype and multilocus sequence type (MLST). Human peripheral blood mononuclear cells (PBMCs) were stimulated for the production of proinflammatory cytokines by live and heat-killed isolates and plasmid DNA; modulation by cellular pathway inhibitors was explored. Survival of 30 mice was recorded after intraperitoneal challenge with susceptible and K. pneumoniae carbapenemase (KPC)-producing isolates. Splenocytes of mice were stimulated for the production of pro- and anti-inflammatory cytokines. Isolates were divided into different patterns of production of tumor necrosis factor alpha (TNF-α) and interleukin-1ß (IL-1ß) poststimulation in relation to both the MLST clone and resistance phenotype. The sequence type 383 (ST383) clone producing Verona integron-encoded metallo-ß-lactamase (VIM) stimulated high production of both TNF-α and IL-1ß. Clone ST17 producing KPC elicited low TNF-α production; this was reversed by Toll-like receptor 9 (TLR9) antagonists, indicating an effect of plasmid DNA. This isolate was linked with early death of mice compared to high-TNF-α-producing isolates. We conclude that KPC-producing isolates seem to be highly virulent in a low-TNF-α-release environment, suggesting an immunoparalysis induction mechanism. KPC plasmids may directly contribute to the immune system stimulation.

A Four-Probiotics Regimen Reduces Postoperative Complications After Colorectal Surgery: A Randomized, Double-Blind, Placebo-Controlled Study.

BACKGROUND: Heterogeneous results of published studies led to conduct a randomized clinical trial to assess the efficacy of a new formulation of four probiotics as prophylaxis for complications after colorectal surgery. METHODS: A double-blind, placebo-controlled randomized study was conducted enrolling patients undergoing colorectal surgery for cancer. Capsules of placebo or of a formulation containing Lactobacillus acidophilus, L. p lantarum, Bifidobacterium lactis and Saccharomyces boulardii were administered starting one day before operation and continuing for another 15 days postoperatively. Patients were followed up for 30 days with the development of postoperative complications as the primary outcome. Gene expression and serum levels of cytokines were measured on postoperative day 4 ( www.clinicaltrials.gov NCT02313519). RESULTS: The study was prematurely stopped after enrolment due to efficacy in the primary outcome. Administration of probiotics significantly decreased the rate of all postoperative major complication (28.6 vs. 48.8 % of the placebo arm, p 0.010, odds ratio 0.42). Major benefit was found in the reduction of the rate of postoperative pneumonia (2.4 vs. 11.3 %, p 0.029), of surgical site infections (7.1 vs. 20.0 %, p 0.020) and of anastomotic leakage (1.2 vs. 8.8 %, p 0.031). The time until hospital discharge was shortened as well. Gene expression of SOCS3 was positively related with gene expression of TNF and of circulating IL-6 in the probiotic group but not in the placebo group. CONCLUSIONS: The studied probiotic formulation significantly decreased the risk of postoperative complications, namely mechanical ventilation, infections and anastomotic leakage. Modulation of the gene expression of SOCS3 is one suggested mechanism ( www.clinicaltrials.gov NCT02313519).

Immunomodulatory intervention with interferon-γ in Escherichia coli pyelonephritis.

PURPOSE: We investigated the efficacy of recombinant human interferon-γ in experimental pyelonephritis due to Escherichia coli. MATERIALS AND METHODS: Pyelonephritis was induced by intrapelvic inoculation of bacteria after ureteral ligation in 38 rabbits assigned to 1 of 3 groups, including group 1-16 controls, group 2-14 rabbits treated with intravenous recombinant human interferon-γ and group 3-8 rabbits treated with intravenous recombinant human interferon-γ plus amikacin. Bacterial counts, cytokines and malondialdehyde were measured in blood. Peripheral blood mononuclear cells were isolated to measure TNFα transcripts, cytokine stimulation and apoptosis. Survival was recorded, and the tissue bacterial load and myeloperoxidase activity were measured after sacrifice. RESULTS: The mortality rate in groups 1, 2 and 3 was 66.7%, 25% and 12.5%, respectively. The circulating bacterial count and tissue bacterial load were less in group 2 than in group 1. Circulating malondialdehyde negatively correlated with the bacterial load of the spleen. Although the number of TNFα transcripts in circulating peripheral blood mononuclear cells did not differ, peripheral blood mononuclear cells isolated from group 2 at 48 hours produced much greater concentrations of tumor necrosis factor-α after stimulation with Pam3Cys. In parallel, the apoptosis rate of circulating monocytes was increased in group 2 at 48 hours. Lung myeloperoxidase activity at 24 hours, serving as indirect evidence of neutrophil infiltration, was decreased in group 2. CONCLUSIONS: Recombinant human interferon-γ administration prolonged survival in rabbits with experimental E. coli urosepsis. Its action was probably related to increased bacterial phagocytosis after modulation of oxidant status and reversal of monocyte immunoparalysis.

Intravenous paracetamol as an antipyretic and analgesic medication: the significance of drug metabolism.

One prospective, open-label, non-randomized study was conducted in 100 patients to define the antipyretic and analgesic effect of a new intravenous formulation of 1 g of paracetamol; 71 received paracetamol for the management of fever and 29 received paracetamol for pain relief after abdominal surgery or for neoplastic pain. Serial follow-up measurements of core temperature and of pain intensity were done for 6 h. Additional rescue medications were recorded for 5 days. Blood was sampled for the measurement of free paracetamol (APAP) and of glucuronide-APAP and N-sulfate-APAP by an HPLC assay. Defervescence, defined as core temperature below or equal to 37.1°C, was achieved in 52 patients (73.2%) within a median time of 3 h. Patients failing to become afebrile with the first dose of paracetamol became afebrile when administered other agents as rescue medications. Analgesia was achieved in 25 patients (86.4%) within a median time of 2 h. Serum levels of glucuronide-APAP were greater among non-responders to paracetamol. The presented results suggest that the intravenous formulation of paracetamol is clinically effective depending on drug metabolism.

Pre-treatment with low-dose endotoxin prolongs survival from experimental lethal endotoxic shock: Benefit for lethal peritonitis by Escherichia coli.

Although LPS tolerance is well-characterized, it remains unknown if it is achieved even with single doses of lipopolysaccharide (LPS) and if it offers protection against lethal bacterial infections. To this end, C57B6 mice were assigned to groups A (sham); B (saline i.p followed after 24h by i.p 30mg/kg LPS); and C (3mg/kg LPS i.p followed after 24h by i.p 30mg/kg LPS). Survival was monitored and animals were sacrificed early after lethal challenge for measurement of tumour necrosis factor-alpha (TNFα) in serum; isolation of splenocytes and cytokine stimulation; and flow-cytometry for apoptosis and TREM-1. Experiments were repeated with mice infected i.p by Escherichia coli after challenging with saline or LPS. Mortality of group B was 72.2% compared with 38.9% of group C (p: 0.020). Serum TNFα of group C was lower than group B. Expression of TREM-1 of group C on monocytes/neutrophils was greater than group B. Release of TNFα, of IFNγ and of IL-17 from splenocytes of group C was lower than group B and the opposite happened for IL-10 showing evidence of cellular reprogramming. In parallel, apoptosis of circulating lymphocytes and of splenocytes of group C was greater compared with group B. Pre-treatment of mice challenged by E. coli with low dose LPS led to 0% mortality compared with 90% of saline pre-treated mice; in these mice, splenocytes improved over-time their capacity for release of IFNγ. It is concluded that single low doses of LPS lead to early reprogramming of the innate immune response and prolong survival after lethal E. coli challenge.

Kinetics of circulating immunoglobulin M in sepsis: relationship with final outcome.

INTRODUCTION: The aim of this study was to investigate the kinetics of immunoglobulin M (IgM) during the different stages of sepsis. METHODS: In this prospective multicenter study, blood sampling for IgM measurement was done within the first 24 hours from diagnosis in 332 critically ill patients; in 83 patients this was repeated upon progression to more severe stages. Among these 83 patients, 30 patients with severe sepsis progressed into shock and IgM was monitored daily for seven consecutive days. Peripheral blood mononuclear cells (PBMCs) were isolated from 55 patients and stimulated for IgM production. RESULTS: Serum IgM was decreased in septic shock compared to patients with systemic inflammatory response syndrome (SIRS) and patients with severe sepsis. Paired comparisons at distinct time points of the sepsis course showed that IgM was decreased only when patients deteriorated from severe sepsis to septic shock. Serial measurements in these patients, beginning from the early start of vasopressors, showed that the distribution of IgM over time was significantly greater for survivors than for non-survivors. Production of IgM by PBMCs was significantly lower at all stages of sepsis compared with healthy controls. CONCLUSIONS: Specific changes of circulating IgM occur when patients with severe sepsis progress into septic shock. The distribution of IgM is lower among non-survivors.

Risk assessment in sepsis: a new prognostication rule by APACHE II score and serum soluble urokinase plasminogen activator receptor.

INTRODUCTION: Early risk assessment is the mainstay of management of patients with sepsis. APACHE II is the gold standard prognostic stratification system. A prediction rule that aimed to improve prognostication by APACHE II with the application of serum suPAR (soluble urokinase plasminogen activator receptor) is developed. METHODS: A prospective study cohort enrolled 1914 patients with sepsis including 62.2% with sepsis and 37.8% with severe sepsis/septic shock. Serum suPAR was measured in samples drawn after diagnosis by an enzyme-immunoabsorbent assay; in 367 patients sequential measurements were performed. After ROC analysis and multivariate logistic regression analysis a prediction rule for risk was developed. The rule was validated in a double-blind fashion by an independent confirmation cohort of 196 sepsis patients, predominantly severe sepsis/septic shock patients, from Sweden. RESULTS: Serum suPAR remained stable within survivors and non-survivors for 10 days. Regression analysis showed that APACHE II ≥ 17 and suPAR ≥ 12 ng/ml were independently associated with unfavorable outcome. Four strata of risk were identified: i) APACHE II <17 and suPAR <12 ng/ml with mortality 5.5%; ii) APACHE II < 17 and suPAR ≥ 12 ng/ml with mortality 17.4%; iii) APACHE II ≥ 17 and suPAR <12 ng/ml with mortality 37.4%; and iv) APACHE II ≥ 17 and suPAR ≥ 12 ng/ml with mortality 51.7%. This prediction rule was confirmed by the Swedish cohort. CONCLUSIONS: A novel prediction rule with four levels of risk in sepsis based on APACHE II score and serum suPAR is proposed. Prognostication by this rule is confirmed by an independent cohort.

Early increase of serum angiopoietin-2 are associated with early progression to death in experimental injury.

Severe trauma induces systemic inflammatory response syndrome (SIRS) through the release of proinflammatory mediators. Angiopoietin-2 (Ang-2) is over-produced in sepsis and leads to dysfunction of endothelial cells and subsequent multiple organ dysfunction. In order to define the role of Ang-2 in lethal injury, 45 rabbits were studied; eight were administered anesthesia; 11 were sham-operated and 26 were subject to femoral injury. Concentrations of Ang-2, malondialdehyde (MDA), tumor necrosis factor-alpha (TNFα) and endotoxins (LPS) were determined in serum and of Ang-2 in tissues; vital signs and overall survival were recorded. Bacterial growth was quantitatively assessed in liver, spleen and lung of animal that died. Survival of injured animals was shorter than sham operated ones. Serum concentrations of Ang-2 at 4 h was greater among animals where death supervened early, i.e. within 48 h after injury than among rabbits that died later. That was also the case for systolic, diastolic and mean arterial pressures. Serum MDA and TNFα and tissue bacterial growth did not differ between rabbits that died early and rabbits that died late. Serum LPS remained below the limit of detection. These results suggest that circulating Ang-2 participates in the pathogenesis of SIRS after injury connected with early haemodynamic instability.

Inhibition of caspase-1 activation in Gram-negative sepsis and experimental endotoxemia.

INTRODUCTION: Down-regulation of ex-vivo cytokine production is a specific feature in patients with sepsis. Cytokine downregulation was studied focusing on caspase-1 activation and conversion of pro-interleukin-1ß into interleukin-1ß (IL-1ß). METHODS: Peripheral blood mononuclear cells were isolated from a) 92 patients with sepsis mainly of Gram-negative etiology; b) 34 healthy volunteers; and c) 5 healthy individuals enrolled in an experimental endotoxemia study. Cytokine stimulation was assessed in vitro after stimulation with a variety of microbial stimuli. RESULTS: Inhibition of IL-1ß in sepsis was more profound than tumour necrosis factor (TNF). Down-regulation of IL-1ß response could not be entirely explained by the moderate inhibition of transcription. We investigated inflammasome activation and found that in patients with sepsis, both pro-caspase-1 and activated caspase-1 were markedly decreased. Blocking caspase-1 inhibited the release of IL-1ß in healthy volunteers, an effect that was lost in septic patients. Finally, urate crystals, which specifically induce the NLPR3 inflammasome activation, induced significant IL-1ß production in healthy controls but not in patients with sepsis. These findings were complemented by inhibition of caspase-1 autocleavage as early as two hours after lipopolysaccharide exposure in volunteers. CONCLUSIONS: These data demonstrate that the inhibition of caspase-1 and defective IL-1 ß production is an important immunological feature in sepsis.

Host response biomarker in sepsis: suPAR detection.

Recent studies of our group have shown that suPAR may complement APACHE II score for risk assessment in sepsis. suPAR may be measured in serum of patients by an enzyme immunosorbent assay developed by Virogates (suPARnostic™). Production of suPAR from circulating neutrophils and monocytes may be assessed after isolation of neutrophils and monocytes and ex vivo culture. This is followed by measurement of suPAR in culture supernatants.

Pre-treatment with probiotics prolongs survival after experimental infection by multidrug-resistant Pseudomonas aeruginosa in rodents: an effect on sepsis-induced immunosuppression.

Based on several randomised clinical studies indicating benefit from oral probiotic intake for the prevention of hospital-acquired infections in critically ill patients, this study aimed to explain the mechanism of action of probiotics for the prevention of lethal experimental infection by multidrug-resistant (MDR) Pseudomonas aeruginosa. Experiments using an Escherichia coli strain susceptible to all antimicrobials were also conducted. C57BL/6 mice were pre-treated intraperitoneally with sterile water for injection or Lactobacillus plantarum. Survival was recorded and mice were sacrificed for measurement of apoptosis and tissue bacterial overgrowth and for isolation and culture of splenocytes for cytokine production. Experiments were repeated after pre-treatment with a commercial preparation of four probiotics (L. plantarum, Lactobacillus acidophilus, Saccharomyces boulardii and Bifidobacterium lactis; LactoLevure(®)). Peripheral blood mononuclear cells (PBMCs) of healthy volunteers were stimulated by heat-killed P. aeruginosa following pre-treatment with medium or probiotics. Pre-treatment with L. plantarum significantly prolonged survival after challenge by either MDR P. aeruginosa (66.7% vs. 31.3%; P=0.026) or E. coli (56.0% vs. 12.0%, P=0.003). Survival benefit was even more pronounced when mice were pre-treated with LactoLevure(®). Tissue bacterial outgrowth and apoptosis of white blood cells and splenocytes were not altered. TNFα and IL-10 production by splenocytes of mice pre-treated with probiotic was increased and IFNγ production was decreased. Pre-treatment with LactoLevure(®) restored production of IL-17. Stimulation of human PBMCs after probiotic pre-treatment was accompanied by reduced gene expression of SOCS3. The results suggest that the protective effect of probiotics is mediated through prevention of sepsis-induced immunosuppression.

NK and NKT Cell Depletion Alters the Outcome of Experimental Pneumococcal Pneumonia: Relationship with Regulation of Interferon-γ Production.

Background. Natural killer (NK) and natural killer T (NKT) cells contribute to the innate host defense but their role in bacterial sepsis remains controversial. Methods. C57BL/6 mice were infected intratracheally with 5 × 10(5) cfu of Streptococcus pneumoniae. Animals were divided into sham group (Sham); pretreated with isotype control antibody (CON) group; pretreated with anti-asialo GM1 antibody (NKd) group; and pretreated with anti-CD1d monoclonal antibody (NKTd) group before bacterial challenge. Serum and tissue samples were analyzed for bacterial load, cytokine levels, splenocyte apoptosis rates, and cell characteristics by flow cytometry. Splenocyte miRNA expression was also analyzed and survival was assessed. Results. NK cell depletion prolonged survival. Upon inhibition of NKT cell activation, spleen NK (CD3-/NK1.1+) cells increased compared to all other groups. Inhibition of NKT cell activation led to higher bacterial loads and increased levels of serum and splenocyte IFN-γ. Splenocyte miRNA analysis showed that miR-200c and miR-29a were downregulated, while miR-125a-5p was upregulated, in anti-CD1d treated animals. These changes were moderate after NK cell depletion. Conclusions. NK cells appear to contribute to mortality in pneumococcal pneumonia. Inhibition of NKT cell activation resulted in an increase in spleen NK (CD3-/NK1.1+) cells and a higher IFN-γ production, while altering splenocyte miRNA expression.

Proinflammatory cytokine responses in patients with psoriasis.

BACKGROUND: Psoriasis is one of the most common, immune-mediated, chronic inflammatory skin diseases. Proinflammatory cytokines play an important pathogenetic role at a local level. OBJECTIVE: To assess whether the proinflammatory cytokines IL-1ß, IL-6, IL-17, IL-22 and TNF-α are released systemically during psoriasis. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from 30 patients with psoriasis and 30 healthy volunteers. Cytokine production was assessed in supernatants using an enzyme immunoassay after stimulation of PBMCs with microbial stimuli. In addition, flow cytometry was used to determine the subsets of monocytes involved and the intracellular TNF-α production in monocytes. RESULTS: IL-17 levels were significantly higher in the supernatants of PBMCs from psoriatic patients after stimulation with phytohemagglutinin. TNF-α production was also significantly higher in cells from psoriatic patients after stimulation with all stimuli, as compared with health volunteers. Similar changes were not found for the other cytokines. A statistically significant difference was observed between patients and controls for inflammatory CD14(+)/CD16(+) monocytes (p<0.0001) and patrolling CD14-/CD16(+) monocytes. CONCLUSION: Hyper-production of TNF-α is documented in psoriasis. These results support the concept that there is a systemic, proinflammatory component in psoriasis.

Function of blood monocytes among patients with orofacial infections.

Few data are available on the significance of the integrity of the innate immune system among patients with orofacial infections. This was assessed in the present study. Peripheral blood mononuclear cells (PBMCs) were isolated from 23 patients with orofacial infections before surgical debridement and from 12 healthy volunteers. PBMCs were stimulated with bacterial endotoxin (LPS) and with Pam3Cys. Concentrations of interleukin (IL)-1ß, IL-6 and tumor necrosis factor-alpha (TNFα) were estimated in supernatants by an enzyme immunoassay. Concentrations of estimated cytokines released from PBMCs of healthy volunteers and of patients did not differ. Intensity of cytokine release after stimulation was related with the time until complete resolution of the infection (p: 0.046). It is concluded that adequate functions of blood monocytes are associated with favorable outcome after surgery for orofacial abscesses. It seems, however, that impairment of monocyte function predisposes to infection persistence.

Role of tumor necrosis factor gene single nucleotide polymorphisms in the natural course of 2009 influenza A H1N1 virus infection.

OBJECTIVES: To identify the role of single nucleotide polymorphisms (SNPs) of the tumor necrosis factor (TNF) gene in the natural course of 2009 influenza A H1N1 virus infection. METHODS: Genomic DNA was isolated from 109 patients with an H1N1 infection and from 108 healthy volunteers. SNPs of the TNF gene were assessed after electrophoresis of the digested PCR products by restriction enzymes. RESULTS: The frequency of the -238 A allele was significantly greater among patients than among controls. Viral pneumonia developed in 20 of 96 non-carriers of at least one -238 A allele (20.8%) and in seven of 13 carriers of at least one -238 A allele (53.8%, p=0.016). Logistic regression analysis showed that the most important factors associated with the development of pneumonia were the presence of an underlying disease (p=0.021, odds ratio (OR) 3.08) and the carriage of at least one -238 A allele (p=0.041, OR 3.74). Gene transcripts of the TNF gene were greater among non-carriers of the -238 A allele than among carriers of the -238 A allele. CONCLUSIONS: The -238 A SNP allele of the TNF gene imposes on the course of 2009 H1N1 virus infection and is an independent risk factor for pneumonia.

Enhanced interleukin-1ß production of PBMCs from patients with gout after stimulation with Toll-like receptor-2 ligands and urate crystals.

INTRODUCTION: Monosodium urate monohydrate (MSU) crystals synergize with various toll-like receptor (TLR) ligands to induce cytokine production via activation of the NOD-like receptor (NLR) family, pyrin domain-containing 3 (NLPR3) inflammasome. This has been demonstrated in vitro using human cell lines or monocytes of healthy volunteers. In the present study, we have investigated the effect of MSU crystals and of their combination with TLR ligands in peripheral blood mononuclear cells (PBMC) of patients with gout. METHODS: PBMCs from 18 patients with primary gout and 12 healthy donors were exposed to MSU crystals in the presence or absence of saturated fatty acid C18:0 (free fatty acid, TLR2 ligand), palmitoyl-3-cystein (Pam3Cys, TLR1/2 ligand) and fibroblast stimulating factor-1 (FSL-1, TLR 2/6 ligand). Production of IL-1ß, IL-6, IL-8, IL-17 and tumor necrosis factor alpha (TNFα) was determined by ELISA. mRNA transcripts of IL-1ß were measured by real-time PCR. RESULTS: MSU crystals alone failed to induce IL-1ß, IL-6 or TNFα in both patients and control groups, but a stronger synergy between MSU/Pam3Cys and MSU/C18:0 for the induction of IL-1ß was found in patients with gout compared to healthy controls. IL-6, but not IL-8, followed the kinetics of IL-1ß. No production of the neutrophil-recruiting IL-17 was detectable after stimulation of the patients' PBMCs with MSU in both the presence or absence of TLR ligands. No change of gene transcripts of IL-1ß after stimulation with MSU and Pam3Cys or with MSU and C18:0 was found. A positive correlation was found between synergy in IL-1ß production from PBMCs of patients between C18:0 and MSU crystals, as well as the annual number of attacks of acute gouty arthritis (rs: +0.649, P: 0.022). CONCLUSIONS: The synergy between MSU crystals and TLR-2 ligands is more prominent in patients with gout than in controls. This is likely mediated by the enhanced maturation of pro-IL-1ß into IL-1ß.

Early changes of procalcitonin may advise about prognosis and appropriateness of antimicrobial therapy in sepsis.

PURPOSE: The objective of this study is to define if early changes of procalcitonin (PCT) may inform about prognosis and appropriateness of administered therapy in sepsis. METHODS: A prospective multicenter observational study was conducted in 289 patients. Blood samples were drawn on day 1, that is, within less than 24 hours from advent of signs of sepsis, and on days 3, 7, and 10. Procalcitonin was estimated in serum by the ultrasensitive Kryptor assay (BRAHMS GmbH, Hennigsdorf, Germany). Patients were divided into the following 2 groups according to the type of change of PCT: group 1, where PCT on day 3 was decreased by more than 30% or was below 0.25 ng/mL, and group 2, where PCT on day 3 was either increased above 0.25 ng/mL or decreased less than 30%. RESULTS: Death occurred in 12.3% of patients of group 1 and in 29.9% of those of group 2 (P < .0001). Odds ratio for death of patients of group 1 was 0.328. Odds ratio for the administration of inappropriate antimicrobials of patients of group 2 was 2.519 (P = .003). CONCLUSIONS: Changes of serum PCT within the first 48 hours reflect the benefit or not of the administered antimicrobial therapy. Serial PCT measurements should be used in clinical practice to guide administration of appropriate antimicrobials.

Effect of the novel influenza A (H1N1) virus in the human immune system.

BACKGROUND: The pandemic by the novel H1N1 virus has created the need to study any probable effects of that infection in the immune system of the host. METHODOLOGY/PRINCIPAL FINDINGS: Blood was sampled within the first two days of the presentation of signs of infection from 10 healthy volunteers; from 18 cases of flu-like syndrome; and from 31 cases of infection by H1N1 confirmed by reverse RT-PCR. Absolute counts of subtypes of monocytes and of lymphocytes were determined after staining with monoclonal antibodies and analysis by flow cytometry. Peripheral blood mononuclear cells (PBMCs) were isolated from patients and stimulated with various bacterial stimuli. Concentrations of tumour necrosis factor-alpha, interleukin (IL)-1beta, IL-6, IL-18, interferon (FN)-alpha and of IFN-gamma were estimated in supernatants by an enzyme immunoassay. Infection by H1N1 was accompanied by an increase of monocytes. PBMCs of patients evoked strong cytokine production after stimulation with most of bacterial stimuli. Defective cytokine responses were shown in response to stimulation with phytohemagglutin and with heat-killed Streptococcus pneumoniae. Adaptive immune responses of H1N1-infected patients were characterized by decreases of CD4-lymphocytes and of B-lymphocytes and by increase of T-regulatory lymphocytes (Tregs). CONCLUSIONS/SIGNIFICANCE: Infection by the H1N1 virus is accompanied by a characteristic impairment of the innate immune responses characterized by defective cytokine responses to S.pneumoniae. Alterations of the adaptive immune responses are predominated by increase of Tregs. These findings signify a predisposition for pneumococcal infections after infection by H1N1 influenza.