Direct stimulation of cytokines (IL-1 beta, TNF-alpha, IL-6, IL-2, IFN-gamma and GM-CSF) in whole blood. I. Comparison with isolated PBMC stimulation

Blood leucocyte cytokine production after LPS stimulation at different concentrations of glucose and/or insulin

BACKGROUND

Previous studies have indicated that alterations in blood glucose and/or insulin levels modify the inflammatory response. The purpose of this study was to elucidate whether increased levels of glucose and/or insulin influence the activation pattern of blood leucocytes and their production of cytokines in vitro.

METHODS

Venous blood was obtained from eight healthy male volunteers after an overnight fast. Glucose and/or insulin were added to aliquots of whole blood to increase the blood glucose concentration by 5 or 20 mmol/l and/or the insulin concentration by 6 or 30 nmol/l, respectively, before stimulation with E. coli lipopolysaccharide (LPS) at concentrations of 10, 100 or 1000 ng/ml. The samples were subsequently incubated at 37 degrees C for 6 h before cytokine measurements. After centrifugation the levels of interleukins (IL)-1beta, IL-6, IL-8, IL-10 and tumour necrosis factor (TNF)-alpha were measured in plasma using enzyme-linked immuno-sorbent assays. The results were compared with cytokine levels in parallel control samples to which only identical amounts of LPS were added.

RESULTS

The LPS-stimulated production of IL-1beta was significantly reduced by on average 26% in samples to which glucose 20 mmol/l was added; addition of insulin and/or glucose 5 mmol/l had no apparent effect on the IL-1beta production at any LPS concentration. The levels of IL-6, IL-8, IL-10 and TNF-alpha were not manifestly altered by addition of glucose and/or insulin at any LPS concentration.

CONCLUSION

A substantial increase in blood glucose concentration changed the IL-1beta production, but not the production of other cytokines, in response to LPS stimulation.

Bacillus anthracis peptidoglycan stimulates an inflammatory response in monocytes through the p38 mitogen-activated protein kinase pathway

We hypothesized that the peptidoglycan component of B. anthracis may play a critical role in morbidity and mortality associated with inhalation anthrax. To explore this issue, we purified the peptidoglycan component of the bacterial cell wall and studied the response of human peripheral blood cells. The purified B. anthracis peptidoglycan was free of non-covalently bound protein but contained a complex set of amino acids probably arising from the stem peptide. The peptidoglycan contained a polysaccharide that was removed by mild acid treatment, and the biological activity remained with the peptidoglycan and not the polysaccharide. The biological activity of the peptidoglycan was sensitive to lysozyme but not other hydrolytic enzymes, showing that the activity resides in the peptidoglycan component and not bacterial DNA, RNA or protein. B. anthracis peptidoglycan stimulated monocytes to produce primarily TNFα; neutrophils and lymphocytes did not respond. Peptidoglycan stimulated monocyte p38 mitogen-activated protein kinase and p38 activity was required for TNFα production by the cells. We conclude that peptidoglycan in B. anthracis is biologically active, that it stimulates a proinflammatory response in monocytes, and uses the p38 kinase signal transduction pathway to do so. Given the high bacterial burden in pulmonary anthrax, these findings suggest that the inflammatory events associated with peptidoglycan may play an important role in anthrax pathogenesis.

In vitro and ex vivo anti-inflammatory activity of quercetin in healthy volunteers

OBJECTIVE

Quercetin, a commonly occurring flavonoid and well known antioxidant, has been suggested to possess other beneficial activities. The present study investigated the possible anti-inflammatory effects of physiologically attainable quercetin concentrations.

METHODS

The effects of quercetin were tested in vitro, i.e., added to blood in the test tube, and ex vivo and in vivo, i.e., in blood taken after 4 wk of administration of quercetin in an intervention study.

RESULTS

Quercetin dose-dependently inhibited in vitro lipopolysaccharide-induced tumor necrosis factor-alpha production in the blood of healthy volunteers. At a concentration of 1 muM, quercetin caused a 23% reduction. The in vitro lipopolysaccharide-induced interleukin-10 production remained unaffected by quercetin. A 4-wk quercetin intervention resulted in a significant increase in plasma quercetin concentration. The supplementation also increased total plasma antioxidant status but did not affect glutathione, vitamin C, and uric acid plasma concentrations. Basal and ex vivo lipopolysaccharide-induced tumor necrosis factor-alpha levels were not altered by the intervention.

CONCLUSION

The present study shows that quercetin increases antioxidant capacity in vivo and displays anti-inflammatory effects in vitro, but not in vivo or ex vivo, in the blood of healthy volunteers. This lack of effect is probably due to their low cytokine and high antioxidant levels at baseline, indicating that neither inflammation nor oxidative stress is present. Only in people with increased levels of inflammation and oxidative stress, e.g., patients with a disease of which the pathology is associated with these two processes, might antioxidant supplementation be fruitful.

Thalidomide suppressed IL-1beta while enhancing TNF-alpha and IL-10, when cells in whole blood were stimulated with lipopolysaccharide

Thalidomide is used to treat erythema nodosum leprosum (ENL). The events that precipitate this inflammatory reaction, which may occur in multibacillary leprosy patients, and the mechanism by which thalidomide arrest ENL, are not known. Thalidomide's ability to inhibit tumor necrosis factor alpha (TNF-alpha) in vitro has been proposed as a partial explanation of its effective treatment of ENL. In in vitro assays, thalidomide can enhance or suppress TNF-alpha. This is dependent on the stimulant used to evoke TNF-alpha; the procedure used to isolate the mononuclear cells from blood, and the predominant mononuclear cell type in the culture. To avoid artifacts that may occur during isolation of mononuclear cells from blood, we stimulated normal human blood with LPS and evaluated the effect of thalidomide and dexamethasone on TNF-alpha, and other inflammatory cytokines and biomarkers. Thalidomide suppressed interleukin 1 beta (IL-1beta) (p = 0.007), and it enhanced TNF-alpha (p = 0.007) and interleukin 10 (IL-10) (p = 0.031). Dexamethasone enhanced IL-10 (p = 0.013) and suppressed IL-1beta, TNF-alpha, interleukin 6 (IL-6), and interleukin 8 (IL-8) (p = 0.013). The two drugs did not suppress: C-reactive protein (CRP), Ig-superfamily cell-adhesion molecule 1 (ICAM 1), tumor necrosis factor receptor 1 (TNFR1), tumor necrosis factor receptor 2 (TNFR2), or amyloid A. In vitro and in vivo evidence is accumulating that TNF-alpha is not the primary cytokine targeted by thalidomide in ENL and other inflammatory conditions.

Low- versus high-baseline epinephrine output shapes opposite innate cytokine profiles: presence of Lewis- and Fischer-like neurohormonal immune phenotypes in humans?

Immunogenetic mechanisms operating within the immune system are known to influence cytokine profiles and disease susceptibility. Yet the role of the individual's neurohormonal background in these processes remains undefined. Hormonal imbalances are documented in immune-related diseases, but it is unclear whether this represents a secondary phenomenon or a primary "defect" related to specific neurohormonal immune phenotype(s). We report that in a large subpopulation of healthy humans the baseline epinephrine output (but not cortisol and sex steroid hormones) correlated inversely with proinflammatory and positively with anti-inflammatory cytokine production. Thus, low vs high epinephrine excretors had a 2- to 5-fold higher TNF-alpha and IL-12 production but 2-fold lower IL-10 production induced by LPS ex vivo. In alternative settings, we found low baseline levels and profoundly blunted stress-induced epinephrine responses but high TNF-alpha levels in Lewis vs Fischer inbred rats. Additionally, isoproterenol, a beta adrenoreceptor agonist suppressed LPS-induced TNF-alpha production, with more pronounced effect in Lewis than in Fischer rats. In human monocytes, epinephrine and the beta(2) adrenoreceptor agonist fenoterol potently inhibited LPS-induced TNF-alpha and IL-12, but stimulated IL-10 production. The order of potency for hormones able to inhibit IL-12 production ex vivo was: epinephrine > norepinephrine > or = 1,25-(OH)(2) vitamin D(3) > hydrocortisone. This indicates that baseline epinephrine conditions cytokine responsiveness and through this mechanism intrinsic hypo- or hyperactive adrenal medullas in some individuals may shape opposite cytokine profiles. Since Lewis and Fischer rats have opposite susceptibility to experimental immunological diseases, this suggests that the parallel human phenotypes could be linked to differing responsiveness and susceptibility to infections and immune/inflammatory-related conditions.

Antinociception occurs with a reversal in alpha 2-adrenoceptor regulation of TNF production by peripheral monocytes/macrophages from pro- to anti-inflammatory

Tumor necrosis factor-alpha (TNF) plays a role in neuropathic pain. During neuropathic pain development in the chronic constriction injury model, elevated TNF levels in the brain occur in association with enhanced alpha 2-adrenoceptor inhibition of norepinephrine release. alpha 2-Adrenoceptors are also located on peripheral macrophage where they normally function as pro-inflammatory, since they increase the production of the cytokine TNF, a proximal mediator of inflammation. How the central increase in TNF affects peripheral alpha 2-adrenoceptor function was investigated. Male, Sprague-Dawley rats had four loose ligatures placed around the right sciatic nerve. Thermal hyperalgesia was determined by comparing hind paw withdrawal latencies between chronic constriction injury and sham-operated rats. Chronic constriction injury increased TNF immunoreactivity at the lesion and the hippocampus. Amitriptyline, an antidepressant that is used as an analgesic, was intraperitoneally administered (10 mg/kg) starting simultaneous with ligature placement (day-0) or at days-4 or -6 post-surgery. Amitriptyline treatment initiated at day-0 or day-4 post-ligature placement alleviated hyperalgesia. When initiated at day-0, amitriptyline prevented increased TNF immunoreactivity in the hippocampus and at the lesion. A peripheral inflammatory response, macrophage production of TNF, was also assessed in the current study. Lipopolysaccharide (LPS)-stimulated production of TNF by whole blood cells and peritoneal macrophages was determined following activation of the alpha 2-adrenoceptor in vitro. alpha 2-Adrenoceptor regulation of TNF production from peripheral immune-effector cells reversed from potentiation in controls to inhibition in chronic constriction injured rats. This effect is accelerated with amitriptyline treatment initiated at day-0 or day-4 post-ligature placement. Amitriptyline treatment initiated day-6 post-ligature placement did not alleviate hyperalgesia and prevented the switch from potentiation to inhibition in alpha 2-adrenoceptor regulation of TNF production. Recombinant rat TNF i.c.v. microinfusion reproduces the response of peripheral macrophages from rats with chronic constriction injury. A reversal in peripheral alpha 2-adrenoceptor regulation of TNF production from pro- to anti-inflammatory is associated with effective alleviation of thermal hyperalgesia. Thus, alpha 2-adrenoceptor regulation of peripheral TNF production may serve as a potential biomarker to evaluate therapeutic regimens.

Measurement of cytokine production using whole blood

Whole blood (WB) ex vivo stimulation assays are useful for measuring cytokine responses due to the easy access of samples from healthy donors and patients and the minimal processing of the sample required. Because the assay mimics the natural environment, WB culture may be the best milieu in which to study cell activation and cytokine production in vitro. Whole blood stimulation has been used to investigate the cellular responsiveness to a variety of stimuli, including bacterial endotoxin (LPS), antigens, allergens, and antibiotics. Various clinical uses of whole blood stimulation assays have been suggested, including the assessment of autoimmune diseases, the monitoring of drug and vaccine efficacy, and immunotoxicity. Thus, whole blood cell culture may be useful in studying the biological effects of potential allergenic and/or antigenic substances or drugs on immune cell activation and cytokine secretion.

Cytokine release in HR-HPV(+) women without and with cervical dysplasia (CIN II and III) or carcinoma, compared with HR-HPV(-) controls

Aims. We investigated the effect of HR-HPV infection on the capacity of the cytokine network in whole blood cultures during carcinogenesis of cervical carcinoma. Methods. Thirty-nine women with moderate dysplasia, severe dysplasia, cervical carcinoma, or without dysplasia formed the study group. The control group consisted of 10 HR-HPV-negative women without CIN. Whole blood cultures were stimulated with phytohemagglutinin (PHA) and concentrations of tumour necrosis factor α (TNFα), interferon γ (IFNγ), interleukin 2 (IL-2), interleukin 12 (IL-12), interleukin 4 (IL-4), and interleukin 10 (IL-10) were determined by ELISAs. Results. A significant increase in cytokine release was detected in HR-HPV-positive women without dysplasia. In women with cervical cancer, release of IFNγ and IL-12 was of the same magnitude as in HR-HPV-positive women without clinical manifestations. Most Th1-type/Th2-type ratios decreased form CIN II to CIN III, and increased from CIN III to invasive carcinoma. Conclusions. (1) Infection with HR-HPV without expression of cervical dysplasia induces activation of the cytokine network. (2) Increases in ratios of Th1-type to Th2-type cytokines at the stage of cervical carcinoma were found by comparison with stage CIN III. (3) Significant changes in the kinetics of cytokine release to a Th2-type immune response in blood of women with cervical dysplasia occurred progressively from CIN II to CIN III.

Monocytic, Th1 and th2 cytokine alterations in the pathophysiology of schizophrenia

A growing body of evidence suggests that changes in the serum levels and cellular production of various cytokines are associated with the immunological abnormalities of schizophrenia. Several studies have examined alterations in T helper type 1 (Th1) and T helper type 2 (Th2) cytokines in schizophrenia. We explored monocytic, Th1 and Th2 cytokines in 43 schizophrenia patients and 50 normal controls. The mitogen-induced production of tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), IL-4, gamma-interferon (IFN-gamma) and IL-2 was measured with enzyme-linked immunosorbent assays before and after antipsychotic treatment. IL-6 and TNF-alpha production by schizophrenic patients was significantly higher than by normal controls, while IL-2, IL-4 and IFN-gamma production was significantly lower in schizophrenic patients. After 6 weeks of antipsychotic treatment, IL-6 and TNF-alpha production was significantly decreased, while IL-4, IFN-gamma and IL-2 productions were not significantly changed. Our results suggest that increased monocytic cytokines and decreased Th1 and Th2 cytokines may be associated with the immunopathogenesis of acute psychotic schizophrenia, and that antipsychotics may play an important role in immune response by decreasing elevated monocytic cytokines.

Immunologic activity of schistosomal and bacterial TLR2 ligands in Gabonese children

Schistosomes carry lipid moieties that interact with the immune system. To understand the consequence of interactions in terms of polarizing the cytokine profiles, the effect of two Toll-like receptor-2 (TLR2) activating schistosomal lipid fractions was studied on whole blood from Gabonese children living in a schistosomiasis endemic area. One fraction contained lysophosphatidylserine [monoacylglycerophosphoserine (lysoGPSer)] plus diacylphosphatidylserine [diacylglycerophosphoserine (GPSer)] while the other contained lysoGPSer and only a trace of GPSer. The effect of these schistosomal lipid fractions was compared with the known bacterial TLR2 ligands PAM3CSK4 and MALP-2. PAM3CSK4 and MALP-2 had preferential IL-10-activating capacities, while the fraction containing lysoGPSer plus GPSer had a strong TNF-alpha-inducing capacity. The fraction containing lysoGPSer was neutral with respect to pro- vs. anti-inflammatory effects. When Th1 and Th2 cytokines were analysed, the schistosomal lipid fraction containing lysoGPSer plus GPSer showed a stronger Th2 response compared to PAM3CSK4, MALP-2 and lysoGPSer alone. Therefore, the study indicates that not only TLR2 ligands derived from bacteria or from parasites can generate distinct cytokine profiles but also that the composition of lipid entities reaching the immune system can be important in leading to different immune outcomes. This information may be important for exploitation of immune modulatory molecules.

Differences in cytokines between non-suicidal patients and suicidal patients in major depression

Several studies have shown that there is an imbalance between pro-inflammatory and anti-inflammatory cytokines in major depressive disorder (MDD). However, little is known about the role of cytokines in suicide. In the present study, amounts of IL-6, IL-2, IFN-gamma, IL-4, and TGF-beta1 produced by mitogen-stimulated whole blood were measured in 36 MDD patients who had recently attempted suicide, 33 non-suicidal MDD patients, and 40 normal controls. The severity of depression symptoms and suicidal behaviors was evaluated using Hamilton's depression rating scale (HDRS), the Lethality Suicide Attempt Rating Scale (LSARS), and the Risk-Rescue Rating (RRR). Non-suicidal MDD patients had significantly higher IL-6 production than suicidal MDD patients and normal controls (p<0.001). Suicidal MDD patients had significantly lower IL-2 compared with non-suicidal patients and normal controls (p<0.001). Both MDD groups, with or without attempted suicide, had significantly lower IFN-gamma and IL-4 and higher TGF-beta1 production. HDRS scores had significant positive correlations with IL-6, IFN-gamma, and the Th1/Th2 ratio and significant negative correlations with IL-4 in non-suicidal depression patients (p<0.005); however, these correlations did not hold true for suicidal patients. Suicidal MDD patients had no significant correlations between the LSARS or RRR scores and cytokine release. Our findings suggest that the immune response has distinct differences between non-suicidal patients and suicidal patients. Non-suicidal MDD may be associated with increased IL-6 production and a Th1/Th2 imbalance with a shift to Th1, while suicidal MDD may be associated with decreased IL-2.

Probiotic, as well as conventional yogurt, can enhance the stimulated production of proinflammatory cytokines

BACKGROUND

Lactic acid bacteria have been shown to stimulate the secretion of cytokines by lymphocytes and monocytes in a strain-dependent manner. Therefore, in this study, the effect of a daily intake of probiotic yogurt on cytokine production in young healthy women was compared with that of a conventional product.

METHODS

For 2 weeks each, subjects consumed 100 g, then 200 g of either a probiotic or a conventional, commercially available yogurt, both containing Lactobacillus bulgaricus and Streptococcus thermophilus with additional Lactobacillus casei DN 114 001 in the probiotic product. Cytokine production in blood culture following stimulation with phytohaemmaglutinin and lipopolysaccharide was measured using Cytometric Bead Array and enzyme-linked immunosorbent assay.

RESULTS

Stimulated production of tumour necrosis factor-alpha increased significantly following consumption of conventional or probiotic yogurt (+63% and +24% compared with baseline, respectively, P < 0.001). There was also a significantly higher production of interleukin (IL)-1beta in the conventional (+40%, P = 0.006) and of interferon gamma in the probiotic group (+108%, P < 0.05). IL-10 decreased following consumption of the probiotic product, but increased significantly after intake cessation (+129%, P < 0.001). No significant differences in cytokine responses between the conventional and the probiotic yogurt were observed.

CONCLUSION

Both conventional and probiotic yogurt enhanced the stimulated production of pro-inflammatory cytokines.

Imbalance between pro-inflammatory and anti-inflammatory cytokines in bipolar disorder

BACKGROUND

The role of cytokines in bipolar disorder is still controversial. Although a few studies have found alterations of cytokines in bipolar disorder, their findings were inconsistent. The aim of this study was to determine whether the cytokines are involved in the pathophysiology of bipolar disorder.

METHODS

A total of 37 manic patients with bipolar disorder and 74 control subjects were recruited. The mitogen-induced production of tumor necrosis factor (TNF)-alpha, interleukin-6 (IL-6), IL-4, interferon (IFN)-gamma, and IL-2 was measured using quantitative sandwich ELISA at the time of admission and 6 weeks after mood stabilizer treatment.

RESULTS

IL-6 and TNF-alpha production of bipolar manic patients was significantly higher than those of normal controls, while IL-4 values of the patients were significantly lower than normal controls. IL-6/IL-4, TNF-alpha/IL-4, IL-2/IL-4, and IFN-gamma/IL-4 ratios were significantly higher in bipolar manic patients than in normal controls. After 6 weeks of treatment, the levels of IL-6 significantly decreased compared with baseline.

LIMITATIONS

The effect of various types of mood stabilizers on cytokine production should be considered.

CONCLUSIONS

These findings suggest that the increased activity of pro-inflammatory cytokines and an imbalance between pro-inflammatory and anti-inflammatory cytokines may play a role in the pathophysiology of bipolar disorder.

Effects of galactooligosaccharide and long-chain fructooligosaccharide supplementation during pregnancy on maternal and neonatal microbiota and immunity--a randomized, double-blind, placebo-controlled study

BACKGROUND

Galactooligosaccharides (GOS) and long-chain fructooligosaccharides (lcFOS) proliferate bifidobacteria in infant gut microbiota. However, it is not known how GOS and FOS influence the microbiota of pregnant women and whether a potential prebiotic effect is transferred to the offspring.

OBJECTIVES

We aimed to test how supplementation with GOS and lcFOS (GOS/lcFOS) in the last trimester of pregnancy affects maternal and neonatal gut microbiota. Variables of fetal immunity were assessed as a secondary outcome.

DESIGN

In a randomized, double-blind, placebo-controlled pilot study, 48 pregnant women were supplemented 3 times/d with 3 g GOS/lcFOS (at a ratio of 9:1) or maltodextrin (placebo) from week 25 of gestation until delivery. Percentages of bifidobacteria and lactobacilli within total bacterial counts were detected by fluorescent in situ hybridization and quantitative polymerase chain reaction in maternal and neonatal (days 5, 20, and approximately 182) stool samples. Variables of fetal immunity were assessed in cord blood by using flow cytometry and cytokine multiplex-array analysis.

RESULTS

The proportions of bifidobacteria in the maternal gut were significantly higher in the supplemented group than in the placebo group (21.0% and 12.4%, respectively; P = 0.026); the proportion of lactobacilli did not differ between the groups. In neonates, bifidobacteria and lactobacilli percentages, diversity and similarity indexes, and fetal immune parameters did not differ significantly between the 2 groups. Mother-neonate similarity indexes of bifidobacteria decreased over time.

CONCLUSIONS

GOS/lcFOS supplementation has a bifidogenic effect on maternal gut microbiota that is not transferred to neonates. The increased maternal bifidobacteria did not affect fetal immunity as measured by a comprehensive examination of cord blood immunity variables.

A comparison of ex vivo cytokine production in venous and capillary blood

We performed a randomized study of the immunological effects of an early measles vaccine given at 4.5 months of age and aimed to obtain venous samples from the infants at baseline and 6 weeks later. If this was not feasible, a capillary sample was obtained. We analysed baseline samples from the first 50 children enrolled in the study to investigate the potential differences in ex vivo cytokine production between venous blood and capillary blood. We also obtained paired venous and capillary blood samples from 11 adult volunteers. Whole blood was stimulated with lipopolysaccharide (LPS) [a Toll-like receptor (TLR)-4 ligand], (S)-(2, 3-bis (palmitoyloxy)-(2-RS)-propyl)-N-palmitoyl-(R)-Cys-(S)-Ser-(S)-Lys4-OH, trihydrochloride (PAM3Cys) (a TLR-2 ligand), phytohaemagglutinin (PHA) or purified protein derivative (PPD). Cytokine concentrations in the supernatants were assessed by a multiplexed assay and were compared between venous and capillary samples in both infants and adults. The production of both the pro- and the anti-inflammatory cytokines, tumour necrosis factor (TNF)-alpha and interleukin (IL)-10, was higher in cultures of capillary blood compared with venous blood. This was found in non-stimulated control samples as well as in blood stimulated with PAM3Cys and PPD. Adults produced more IL-5 in venous blood than in capillary blood upon PHA stimulation. We found no other difference in the levels of IL-5 or IFN-gamma between venous and capillary blood. In capillary blood we found sex differences in response to PHA but this was not the case in venous blood. We found significant differences in the production of cytokines between venous and capillary blood. Such differences should be taken into account when setting up immuno-epidemiological studies.

EFFECTS OF CD14-159 C/T POLYMORPHISM ON CD14 EXPRESSION AND THE BALANCE BETWEEN PROINFLAMMATORY AND ANTI-INFLAMMATORY CYTOKINES IN WHOLE BLOOD CULTURE

CD14 is an important receptor of innate immunity. When CD14 is anchored by ligands to LPS, peptidoglycans, or lipoteichoic acid, it can result in either proinflammatory or anti-inflammatory responses. To determine whether CD14-159 C/T polymorphism is associated with CD14 expression and the balance of proinflammatory and anti-inflammatory responses, we studied 118 healthy ethnic Han Chinese using a whole blood culture model. The CD14-159 C/T polymorphism was determined by polymerase chain reaction and subsequent HaeIII restriction enzyme digestion of the polymerase chain reaction products. Meanwhile, CD14 mRNA expression in leukocytes and the levels of soluble CD14, TNF-alpha, IL-6, and IL-10 were also determined in the supernatants. Among the 118 individuals, there were 40 TT homozygotes, 62 heterozygotes, and 16 subjects homozygous for C allele. After LPS stimulation, the levels of CD14 mRNA expression in TT and TC genotypes were significantly higher than in CC homozygotes (P = 0.017), and soluble CD14 levels were also higher than in CC genotypes (P = 0.008). In addition, TT homozygotes had the highest LPS-stimulated TNF-alpha, IL-6 production (P = 0.044, P = 0.004), and the lowest IL-10 release (P = 0.003). In conclusion, CD14-159 C/T polymorphism is correlated with CD14 expression and may thus influence the balance of proinflammatory and anti-inflammatory responses in ethnic Han Chinese. These results suggest that CD14-159 C/T polymorphism might partly explain the difference in predisposition to develop complications of infectious diseases in different patients and may provide a therapeutic target for sepsis intervention strategies.

Cytokine imbalance in the pathophysiology of major depressive disorder

OBJECTIVE

A substantial body of evidence indicates that dysregulation of the immune system is associated with Major Depressive Disorder (MDD). Because most cytokines have pleiotropic effects, we measured various subsets of cytokines to examine the association between immune response and MDD.

METHODS

Forty-eight hospitalized MDD patients and 63 normal controls were recruited. We measured in vitro monocytic (IL-6 and tumor necrosis factor (TNF)-alpha), Th1 (interferon (IFN)-gamma and interleukin (IL)-2), Th2 (IL-4), and Treg (transforming growth factor (TGF)-beta1) cytokine production as well as IL-2/IL-4 and IFN-gamma/IL-4 ratios for both groups. Depressive symptoms were assessed by Hamilton Depression Rating Scale. Patients were evaluated before and after 6 weeks of antidepressant treatment.

RESULTS

At admission, IL-6, TNF-alpha, TGF-beta1 production, and IFN-gamma/IL-4 ratio were significantly higher, whereas IFN-gamma, IL-2, and IL-4 were significantly lower in MDD patients. After treatment, IL-6 and TGF-beta1 production were significantly lower than before treatment.

CONCLUSION

We suggest that activation of monocytic proinflammatory cytokines, and inhibition of both Th1 and Th2 cytokines may be associated with immunological dysregulation in MDD. TGF-beta1 may be associated with the regulation of monocytic cytokines as well as Th1 and Th2 cytokines in MDD.

Immunomodulatory effect of exo-polysaccharides from submerged cultured Cordyceps sinensis: enhancement of cytokine synthesis, CD11b expression, and phagocytosis

Cordyceps sinensis is widely used as a traditional medicine for treatment of a wide variety of diseases or to maintain health. The immunomodulatory activity of polysaccharides prepared from submerged cultured C. sinensis BCRC36421 was investigated in human peripheral blood. Results demonstrated that Fr. A (exo-polysaccharides, 0.025 approximately 0.1 mg/ml) induced the production of tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-6, and IL-10 dose-dependently. Fr. A, as low as 0.025 mg/ml, could significantly augment surface expression of CD11b in monocytes and polymorphonuclear neutrophils. Functional assay revealed that Fr. A (0.05 mg/ml) also elevated phagocytosis in monocytes and PMN. On the other hand, Fr. B (intracellular polysaccharides) only moderately induced TNF-alpha release, CD11b expression, and phagocytosis at the same concentrations. Our results indicate that the immunomodulatory components of submerged cultured C. sinensis mainly reside in the culture filtrate.

Stimulated production of interleukin-8 covaries with psychosocial risk factors for inflammatory disease among middle-aged community volunteers

A growing literature suggests that psychosocial factors, such as chronic stress and depression, are associated with increased vulnerability to inflammatory disease; however, the mechanisms of this effect remain unclear. One possibility is that these psychosocial characteristics are associated with activation of innate inflammatory pathways. Here, we explore relationships between a range of psychosocial risk factors for inflammatory disease and a measure of inflammatory potential, lipopolysaccharide-induced production of the monocyte-derived proinflammatory cytokines/chemokines interleukin (IL)-1beta, IL-6, TNF-alpha, and IL-8 among a community sample of 183 healthy adults aged 30-54 years. After controlling for demographic factors, health behavior practices, blood pressure, and white blood cell count, hierarchical regression analyses revealed a positive relationship between production of IL-8 and symptoms of depression, trait negative affect, and perceived stress. In contrast, there was an inverse relationship between IL-8 production and perceived social support. Relationships between IL-8 and symptoms of depression and perceived stress were attributable primarily to dispositional differences in NA. The relationship between negative affect measures and IL-8 was independent of social support. Although there were significant univariate associations between higher IL-6 production and symptoms of depression and less social support, these relationships did not withstand adjustment for demographic controls. There were no significant associations between IL-1beta or TNF-alpha and any of the psychosocial parameters. Our findings suggest that individuals at greater psychosocial risk for the development of inflammatory diseases, including cardiovascular disease, also show greater stimulated production of the proinflammatory chemokine, IL-8. Further exploration of this potential psychophysiological pathway is warranted.

In Vitro Restoration of Post-Operatively Decreased IFN-Gamma Levels After Cardiac Surgery and Its Effect on Pro- and Anti-Inflammatory Mediators

BACKGROUND

A decreased synthesis of interferon gamma (IFN-gamma) by TH 1 lymphocytes after cardiac operations with cardiopulmonary bypass (CPB) is part of the inflammatory response to local operative and systemic traumas. The consequences of this mechanism on the release of pro- and anti-inflammatory cytokines remain unclear. To evaluate the role of IFN-gamma, we added recombinant IFN-gamma to peripheral blood mononuclear cells (PBMCs) on the first post-operative day in an attempt to restore pre-operative values and then measured the release of pro- and anti-inflammatory cytokines in vitro.

METHODS

PBMCs of 10 patients scheduled for elective coronary artery bypass grafting (CABG) were obtained pre-operatively (d0) and on the first (d1) and third (d3) post-operative days. The release of IL-6, IL-8, TNF-alpha, IFN-gamma, IL-10, IL-2, and IL-4 was studied after stimulation (48 h) with PHA (phytohemagglutinin) and LPS (lipopolysaccharide) in the absence or presence of recombinant human IFN-gamma.

RESULTS

Endogenous IFN-gamma synthesis was suppressed on d1. Adding exogenous IFN-gamma restored IFN-gamma levels to normal on d1 and doubled IFN-gamma levels on d0 and d3. The addition of IFN-gamma increased TNF-alpha levels up to 250% on d1 and IL-2 synthesis by 75% on d1 and d3; the IL-2 levels, however, were still significantly depressed. The addition of recombinant IFN-gamma did not affect the synthesis of IL-6, IL-8, IL-10, and IL-4.

CONCLUSIONS

Contrary to our expectations, the in vitro release of IL-6 and IL-8 as well as IL-10 and IL-4 was not influenced by the addition of IFN-gamma. However, TNF-alpha production in isolated PBMC cultures increased significantly on the first post-operative day. This may indicate a hyper-reactivity of PBMCs to IFN-gamma and suggests that the decrease in IFN-gamma synthesis might prevent an excessive stimulation of the non-specific immune system by high TNF-alpha levels after cardiac surgery.

The effect of CD14-c159T genotypes on the cytokine response to endotoxin by peripheral blood mononuclear cells from asthmatic children

BACKGROUND

A C-T polymorphism at position 159 in the promoter of CD14 (C-159T) modulates the cellular response to endotoxin and significantly influences total IgE levels. The effect of this genetic variant on the cytokine response of the inflammatory cells is incompletely understood.

OBJECTIVE

To investigate the effects of CD14-C159T genotypes on the response to endotoxin by peripheral blood mononuclear cells (PBMCs) in children with asthma.

METHODS

The PBMCs from asthmatic children with the TT (n = 11) and CC (n = 11) genotypes at the CD14 promoter were cultured in the presence of endotoxin, 100 ng/mL; concanavalin A, 10 microg/mL; or medium alone. Concentrations of soluble CD14 (sCD14), interleukin (IL) 1beta, IL-4, IL-10, IL-12, IL-13, interferon-gamma, and transforming growth factor beta were determined in culture supernatants by enzyme-linked immunosorbent assay, and the transcriptional differences were evaluated using reverse-transcriptase polymerase chain reaction.

RESULTS

Under unstimulated conditions, children with the TT genotype produced higher levels of sCD14 into the culture supernatant compared with children with the CC genotype (P = .03, Mann Whitney U test). Both IL-10 and IL-1beta concentrations were significantly higher in culture supernatants of children with the TT genotype after endotoxin stimulation (P = .02 and P = .009, respectively, by analysis of covariance [ANCOVA]). Messenger RNA expression was consistent with the results of protein concentration for IL-10 and sCD14. Concanavalin A stimulation resulted in lower levels of IL-4 in children with the TT genotype (P = .02, ANCOVA).

CONCLUSION

The genotype at the CD14 promoter C159T locus may significantly influence the cytokine response of PBMCs obtained from asthmatic children. Differences in IL-10 and IL-4 production by alternative genotypes may contribute to the observed genotype effect on total IgE.

Antidepressants suppress production of the Th1 cytokine interferon-gamma, independent of monoamine transporter blockade

In this study, antidepressants with selectivity for the noradrenaline transporter (reboxetine and desipramine), or the serotonin transporter (fluoxetine and clomipramine) were examined in terms of their ability to promote an anti-inflammatory cytokine phenotype in human blood. In addition, we examined the ability of trimipramine; a tricyclic antidepressant that is devoid of monoamine reuptake inhibitory properties on cytokine production. Lipopolysaccharide (LPS) was used to stimulate monocyte-derived pro-inflammatory (IL-1beta, TNF-alpha, IL-12) and anti-inflammatory (IL-10) cytokines, whilst concanavalin A (Con A) was used to stimulate T-cell (Th(1): IFN-gamma and Th(2/3): IL-10) cytokines. All of the antidepressants suppressed IFN-gamma production in the 10-50 microM concentration range, irrespective of their preference for serotonin or noradrenaline transporters. This suppression of IFN-gamma production was paralleled by reduced T-cell proliferation, therefore we suggest that the ability of antidepressants to suppress IFN-gamma production may be related to their anti-proliferative properties. The fact that trimipramine also suppressed IFN-gamma production and T-cell proliferation indicates that these immunomodulatory actions of antidepressants are most likely unrelated to inhibition of monoamine reuptake. Interestingly, exposure to a lower concentration (1 microM) of the antidepressants tended to increase T-cell-derived IL-10 production, with significant effects elicited by the noradrenaline reuptake inhibitors reboxetine and desipramine. In contrast to the robust actions of antidepressants on T-cell derived cytokine production, they failed to induce any consistent change in LPS-induced monocyte cytokine production. Overall, our results indicate that IFN-gamma producing T-cells (Th(1) cells) are the major target for the immunomodulatory actions of antidepressants, and provide evidence questioning the relationship between the monoaminergic reuptake properties of antidepressants and their immunomodulatory effects. The potential clinical significance of the anti-inflammatory actions of antidepressants is discussed.

Randomized clinical trial on cognitive therapy for depression in women with metastatic breast cancer: Psychological and immunological effects

Objective:Depression is particularly prevalent in patients with advanced cancer. Cognitive therapy (CT) is an empirically supported treatment for depression in the general population. However, efficacy remains to be demonstrated in patients with advanced cancer. A prior controlled trial of CT in a group format showed improvements in depression, mood disturbance, and self-esteem; however, these effects were not maintained over time. Studies examining the efficacy of individual format CT interventions that may ensure more long-term maintenance of benefits are necessary. This study assessed the efficacy of CT for depression administered individually in women with metastatic breast cancer and its effect on immune function.

Method: Forty-five women were randomly assigned to either individual CT or to a waiting-list control (WLC) condition. CT was composed of eight weekly sessions of CT and three booster sessions administered at 3-week intervals following the end of treatment.

Results: Patients treated with CT had significantly lower scores on the Hamilton Depression Rating Scale at posttreatment compared to untreated patients. Pooled data from both groups indicated significant reductions of depressive symptoms from pre- to posttreatment, as well as reduction of associated symptoms including anxiety, fatigue, and insomnia symptoms. These effects were well sustained at the 3- and 6-month follow-up evaluations. CT for depression did not appear to have a significant impact on immune functioning.

Significance of results: Findings of this study support the efficacy of CT for depression in this population and suggest that the administration of individual and booster sessions after treatment termination may be instrumental in sustaining the treatment effects over time.

Effects of hyperglycemia, hyperinsulinemia, and hyperosmolarity on neutrophil apoptosis

BACKGROUND

Hyperglycemia is an independent risk factor for increased mortality of critically ill surgical patients, but despite the recognized clinical benefits of early insulin treatment, there is a lack of understanding of the cellular and molecular mechanisms behind this phenomenon. We hypothesized that polymorphonuclear neutrophils, the first line of the innate immune defense system, suffer from altered apoptotic turnover when exposed to hyperglycemic conditions, ultimately decreasing the number of viable cells active at a site of infection.

METHODS

Venous blood samples were drawn from 10 volunteers and incubated for 0.5 or 24 h in a 1:10 dilution with RPMI 1640 medium at various glucose and insulin concentrations. Mannitol was used to control for increased osmolarity. In addition, all samples were incubated either with low-dose lipopolysaccharide (LPS) (1 ng/mL) or without LPS. Neutrophils were extracted using Ficoll-Hypaque density centrifugation and stained with annexin V and propidium iodide. Fluorescence was detected by flow cytometry and analyzed using CellQuest software.

RESULTS

The mean percentage of apoptotic neutrophils after 24 h of incubation at physiologic glucose concentrations (100 mg/dL) was 42.2 +/- 4.1%; exposure to low-dose LPS decreased this number to 18.4 +/- 2.5% (p < 0.01). Neither the exposure to low (10 mg/dL) nor increasingly high (200 or 400 mg/dL) glucose concentrations altered these percentages significantly. Exposing whole blood to increasing osmolarity (addition of 5.5 mM and 16.5 mM mannitol to simulate 200 and 400 mg/dL glucose) led to a mean absolute reduction of the percentage of apoptotic neutrophils to 34.6 +/- 3.6% (+5.5 mOsm; p < 0.05) and 32.3 +/- 4.5% (16.5 mOsm; p < 0.01), respectively.

CONCLUSIONS

The ability of neutrophils to enter their apoptotic program in cultured whole blood withstands short-term changes in glucose and insulin concentrations. Neither hyperglycemia nor hypoglycemia led to a significant alteration of the apoptotic turnover of these cells, suggesting that the increased rate of infectious complications in short-term hyperglycemic critically ill patients may not be traced to increased apoptosis of neutrophils. However, isolated hyperosmolarity reduces neutrophil apoptosis, an observation that may warrant future investigation.

Polymyxin B-conjugated alpha 2-macroglobulin as an adjunctive therapy to sepsis: Modes of action and impact on lethality

A drug targeting both the inflammatory initiators (lipopolysaccharide; LPS) and mediators [tumor necrosis factor-alpha (TNF-alpha)] should have advantage over a "single-factor targeting strategy" in sepsis prevention trials. We have prepared conjugates of polymyxin B (PMB) and the cytokine binding protein alpha2-macroglobulin (A2M). The conjugate binds TNF-alpha as well as LPS as studied by electrophoresis and phase partitioning. Compared with free PMB, the conjugate is nontoxic to cells and does not affect the viability of human monocytes. The A2M-PMB conjugate binds to the A2M receptor (CD91/low-density lipoprotein receptor-related protein 1) with affinity similar to that of the nonmodified protein. Fluorescein isothiocyanate-labeled LPS in the presence of A2M-PMB is rapidly transported into fibroblasts for degradation via receptor-mediated endocytosis. In vitro, A2M-PMB demonstrated inhibition of LPS-induced secretion of TNF-alpha from isolated monocytes as well as in the whole blood assay. The efficacy of the drug was tested in mice after induction of acute inflammation (LPS model) and after induction of a polymicrobial sepsis by cecal ligation and puncture (CLP) model. Treatment of mice with A2M-PMB up to 250 microg/g body weight was not toxic to the animal. When the drug was administered 30 min before or 30 min after the LPS challenge, a survival rate of 90 and 70%, respectively, was obtained compared with the placebo control group (5%). A2M-PMB also protected mice after induction of polymicrobial sepsis when administered 30 min before CLP. These results support our hypothesis that A2M-PMB acts as a polyvalent drug to target different host mediators as well as sepsis inducer at the same time.

Sensitive and Quantitative Measurement of Gene Expression Directly from a Small Amount of Whole Blood

Background: Accurate and precise quantification of mRNA in whole blood is made difficult by gene expression changes during blood processing, and by variations and biases introduced by sample preparations. We sought to develop a quantitative whole-blood mRNA assay that eliminates blood purification, RNA isolation, reverse transcription, and target amplification while providing high-quality data in an easy assay format.

Methods: We performed single- and multiplex gene expression analysis with multiple hybridization probes to capture mRNA directly from blood lysate and used branched DNA to amplify the signal. The 96-well plate singleplex assay uses chemiluminescence detection, and the multiplex assay combines Luminex-encoded beads with fluorescent detection.

Results: The single- and multiplex assays could quantitatively measure as few as 6000 and 24 000 mRNA target molecules (0.01 and 0.04 amoles), respectively, in up to 25 μL of whole blood. Both formats had CVs &lt;10% and dynamic ranges of 3–4 logs. Assay sensitivities allowed quantitative measurement of gene expression in the minority of cells in whole blood. The signals from whole-blood lysate correlated well with signals from purified RNA of the same sample, and absolute mRNA quantification results from the assay were similar to those obtained by quantitative reverse transcription-PCR. Both single- and multiplex assay formats were compatible with common anticoagulants and PAXgene-treated samples; however, PAXgene preparations induced expression of known antiapoptotic genes in whole blood.

Conclusions: Both the singleplex and the multiplex branched DNA assays can quantitatively measure mRNA expression directly from small volumes of whole blood. The assay offers an alternative to current technologies that depend on RNA isolation and is amenable to high-throughput gene expression analysis of whole blood.

Endotoxin inhibits apoptosis but induces primary necrosis in neutrophils

Lipopolysaccharide (LPS) is known to prolong the functional lifespan of neutrophils at a site of infection by preventing apoptosis through inhibitor of apoptosis proteins (IAPs). We hypothesized that the increased neutrophil lifespan ultimately leads to a larger fraction of cells undergoing uncontrolled, primary necrosis. Diluted venous whole blood was incubated with increasing concentrations of LPS for up to 36 hr. The percentages of apoptotic, necrotic and viable neutrophils were assessed using the Annexin V/propidium iodide flow cytometric assay. LPS led to a reduction of neutrophil apoptosis and increased the number of viable cells at 12, 24, and 36 hr of incubation. At the same time intervals, there was a significant increase in the percentage of cells undergoing primary necrosis for all concentrations of LPS (e.g., 10 ng/ml LPS at 24 h produced a mean increase from 9.6% in controls to 30.6%, p < 0.001). This increase in direct neutrophil necrosis following LPS activation may amplify local proinflammatory effects through less well controlled release of neutrophil contents into surrounding tissue.

A case of unfulfilled expectations. Cytokines in idiopathic minimal lesion nephrotic syndrome

Idiopathic minimal lesion nephrotic syndrome (IMLNS) was proposed to be a disorder of T-cell dysfunction by Shalhoub in 1974. The mechanisms by which T-cells increase glomerular permeability have remained elusive (and unproven). There is evidence that IMLNS may be due to a circulating factor released from activated T-cells. In recent years, efforts have been made to identify this pathogenetic cytokine as well as to understand the mechanism(s) for the increased release of this factor. This review attempts to critically analyze the available published data. Using different methodologies, investigators have focused on the production of cytokines in patients with IMLNS during relapse and remission. This has resulted in a plethora of data without definitive conclusions. The pathogenetic cytokine has not been identified, and it is questionable whether there is a Th2 dominance in IMLNS. The review of the available data illustrates the difficulties encountered when one is studying the cytokine secretory pattern in patients with IMLNS. Differences in patient population, type of cells studies, sample preservation, and methodology used to measure cytokines are some of the factors that could account for the disparity of observed results.

The in vitro immune modulation by cadmium depends on the way of cell activation

Among environmental contaminants known for their toxicity and worldwide distribution, heavy metals are of primary concern. Although the toxicology of cadmium (Cd) has been extensively studied, little information is available on the immunomodulation driven by exposure to low doses of Cd. We aimed to evaluate the immunomodulatory effects elicited by short-term exposure of human immunocompetent cells to low biologically relevant doses of Cd in two activation models. Human peripheral blood mononuclear cells, activated either by bacterial antigens (heat-killed Salmonella Enteritidis) or monoclonal antibodies (mAb: anti-CD3/anti-CD28/anti-CD40), were exposed to Cd acetate for 24h. Cell vitality was determined by MTT assay, cytokine release by ELISA, and cytokine gene expression by real-time RT-PCR. The results demonstrated that, in addition to the known toxic effects of Cd, doses from 0.013 to 13.3 microM exert differential effects on cytokine production. In the case of mAb-activation, secretion of interleukin (IL)-1 beta, tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma was greatly inhibited at low Cd doses compared to production of IL-4 and IL-10. This indicates a type-2-biased immune response. Under stimulation by bacterial antigens, release of IL-10 was highly suppressed compared to that of IFN-gamma and TNF-alpha; IL-4 was undetectable. These results imply that low Cd doses exert immunomodulatory effects and the direction of this modulation depends on the pathway to cell activation. Overall, Cd polarizes the immune response toward type-2 in cells stimulated via T cell receptors. However, a polarized type-1 response induced by bacterial antigens could not be overwhelmed by the effects of Cd.

Increased production of IL-1alpha and TNF-alpha in lipopolysaccharide-stimulated blood from obese patients with non-alcoholic fatty liver disease

Enhanced pro-inflammatory cytokine production is considered a pathogenic factor in non-alcoholic fatty liver disease (NAFLD). Peripheral blood production of interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha) was studied in relation to the severity of histological changes of the liver in obese NAFLD patients. Basal levels in serum and production of IL-1alpha and TNF-alpha in peripheral blood cell cultures after stimulation with lipopolysaccharide (enzyme-linked immunoabsorbent assays) were measured in 11 patients with steatosis and 15 with steatohepatitis, who underwent gastrectomy with a gastro-jejunal anastomosis in roux and Y, and in 9 controls who underwent anti-reflux surgery. Production of IL-1alpha and TNF-alpha was 122 and 67% higher in patients with steatosis than control values, respectively. In patients with steatohepatitis, IL-1alpha production was 300 and 80% higher and that of TNF-alpha 110 and 26% higher, as compared with controls and steatosis patients, respectively. Production of IL-1alpha was positively correlated with that of TNF-alpha (r=0.78, p<0.0001). IL-1alpha and TNF-alpha production were both positively correlated with the degree of steatosis (r=0.68, p<0.001 and r=0.74, p<0.0001) and steatohepatitis (r=0.77 and r=0.75, p<0.0001) at liver biopsy, and with the homeostasis model assessment index (r=0.73, p<0.0001 and r=0.63, p<0.01), respectively. Basal serum IL-1alpha and TNF-alpha levels were comparable in the three groups studied. It is concluded that elevated production of IL-1alpha and TNF-alpha by in vitro stimulated whole blood cell cultures occurs in NAFLD obese patients, which might play a pathophysiological role upon inflammatory leukocyte infiltration of the liver.

Effects of polyphenols on human Th1 and Th2 cytokine production

BACKGROUND

Numerous phenolic compounds are consumed in the diet in a range of foods. There are very few studies of the effects of these compounds on the production of lymphocyte-derived cytokines.

AIM OF THE STUDY

To investigate the effects of five phenolic compounds on cytokine production by cultured human lymphocytes.

METHODS

Human whole blood cultures were stimulated with the T cell stimulant concanavalin A for 48 h in the presence of phenolic compounds (vanillic acid, syringic acid, kaempferol, oleuropein and tyrosol) at concentrations up to 10(-4) M. Interleukin (IL)-2, IL-4 and interferon-gamma (IFN-gamma) concentrations were measured in the culture supernatants by ELISA.

RESULTS

IFN-gamma concentration was significantly lower in cultures containing 10(-4) M kaempferol than in cultures with kaempferol at 10(-7), 10(-6)and 10(-5) M or without kaempferol. The other phenolic compounds did not affect IFN-gamma concentration and none of the phenolics tested affected IL-2 or IL-4 concentrations.

CONCLUSIONS

Some, but not all, phenolic compounds can decrease IFN-gamma production by stimulated human whole blood cultures.

Monocytes of preeclamptic women spontaneously synthesize pro-inflammatory cytokines

The maternal syndrome preeclampsia is characterized by a generalized inflammatory response with activation of circulating leukocytes and altered levels of inflammatory cytokines. We hypothesized that one potential source of inflammatory cytokines during preeclampsia is the circulating maternal monocytes. By using flow cytometry, we found that the spontaneous intracellular synthesis of IL-1beta, IL-6, and IL-8 in monocytes of preeclamptic women was higher than in normal pregnant and non-pregnant women. The highest levels of cytokines were detected in women with the most abnormal laboratory values. When stimulated with lipopolysaccharide (LPS), the percentage of IL-1beta+ monocytes was lower in preeclampsia (72.6% +/- 8.2 SEM) than in normal pregnancy (90.7% +/- 2 SEM) (P = 0.03) and non-pregnant women (92.5% +/- 1.4 SEM) (P = 0.04) suggesting that monocytes from preeclamptic patients cannot be further stimulated. These results indicate that maternal circulating monocytes represent a source of inflammatory cytokines during preeclampsia.

Sleep-like concentrations of growth hormone and cortisol modulate type1 and type2 in-vitro cytokine production in human T cells

Slow wave sleep (SWS) is characterized by maximum release of growth hormone (GH) and minimum release of cortisol. We hypothesized that this hormonal pattern during SWS leads, in addition to generally increased T cell cytokine production, to a shift towards type1 cytokines. To test this hypothesis, blood was sampled from 8 humans during SWS, and whole blood cultures were activated in-vitro with ionomycin and phorbol-myrestate-acetate (PMA) in the absence and presence of GH neutralizing antibody (Ab) or physiological concentrations of cortisol. Production of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), IL-4, and tumor necrosis factor-alpha (TNF-alpha) was measured using multiparametric flow cytometry. GH Ab decreased IFN-gamma+CD4+ cells but had no effect on other cytokines. Cortisol alone and in combination with GH Ab decreased CD4+ and CD8+ cells producing IFN-gamma, TNF-alpha and IL-2. Simultaneously, these two reactants reduced IL-4+CD4+ cells, so that the ratio of IFN-gamma/IL4 producing CD4+ cells indicated an unexpected shift towards type1 dominance. Results support the view that release of GH by increasing particularly production of IFN-gamma can contribute to the shift in type1/type2 balance towards type1 activity characterizing SWS. Suppression of cortisol during this sleep period enhances both type1 and type2 activity. Yet, our finding of predominant type1 activity after cortisol administration, rules out any relevance of this suppression for the shift towards type1 activity during SWS.

Extracorporeal blood oxygenation and ozonation (EBOO): a controlled trial in patients with peripheral artery disease

BACKGROUND

Since 1990 our group has been using extracorporeal circulation to ozonate blood by an original method, known as extracorporeal blood oxygenation and ozonation (EBOO), with the aim of amplifying the results observed with ozone autohemotherapy.

OBJECTIVE

To verify the hypothesis that EBOO improves the skin lesions typical of peripheral artery disease (PAD) patients.

METHODS

Twenty-eight patients with PAD were randomized to receive EBOO or intravenous prostacyclin in a controlled clinical trial. The primary efficacy parameters were regression of skin lesions and pain,and improvement in quality of life and vascularisation.

RESULTS

Patients treated with EBOO showed highly significant regression of skin lesions with respect to patients treated with prostacyclin. Other parameters that were significantly different in the two groups of patients were pain,pruritus, heavy legs and well-being. No significant differences in vascularisation of the lower limbs before and after treatment were found in either group. No side effects or complications were recorded during the 210 EBOO treatments.

CONCLUSION

EBOO was much more effective than prostacyclin for treating skin lesions in PAD patients and also had a positive effect on patient general condition without any apparent change in arterial circulation. This suggests other mechanisms of action of EBOO.

Spinal Manipulative Therapy Reduces Inflammatory Cytokines but Not Substance P Production in Normal Subjects

OBJECTIVE

To examine the effect of a single spinal manipulation therapy (SMT) on the in vitro production of inflammatory cytokines, tumor necrosis factor alpha, and interleukin (IL) 1beta, in relation to the systemic (in vivo) levels of neurotransmitter substance P (SP).

METHODS

Sixty-four asymptomatic subjects were assigned to SMT, sham manipulation, or venipuncture control group. SMT subjects received a single adjustment in the thoracic spine. Blood and serum samples were obtained from subjects before and then at 20 minutes and 2 hours after intervention. Whole-blood cultures were activated with lipopolysaccharide (LPS) for 24 hours. Cytokine production in culture supernatants and serum SP levels were assessed by specific immunoassays.

RESULTS

Over the study period, a significant proportion (P </= .05) of sham and control subjects demonstrated progressive increases in the synthesis of tumor necrosis factor alpha and IL-1beta. Conversely, in a comparable proportion of cultures from SMT-derived subjects, the production of both cytokines decreased gradually. Normalization of the observed alterations to reflect the changes relative to self-baselines demonstrated that, within 2 hours after intervention, the production of both cytokines increased significantly (P < .001 to .05) in both controls. In contrast, a significant (P < .001 to .05) reduction of proinflammatory cytokine secretion was observed in cultures from SMT-receiving subjects. In all study groups, serum levels of SP remained unaltered within 2 hours after intervention.

CONCLUSIONS

SMT-treated subjects show a time-dependent attenuation of LPS-induced production of the inflammatory cytokines unrelated to systemic levels of SP. This suggests SMT-related down-regulation of inflammatory-type responses via a central yet unknown mechanism.

Leukocyte activation by malarial pigment

Malarial pigment, a unique hemozoin crystal composed of unit cells of heme dimers, is present in large amounts in circulating monocytes and neutrophils and can persist unchanged in macrophages for several months. In the present study, we investigated the effect of hemozoin not only on macrophages, but also on neutrophils. We used beta-hematin (BH), a chemically synthetic crystal structurally identical to hemozoin, for these studies. In vitro, BH up-regulated the expression of tumor necrosis factor-alpha in whole blood and in isolated peritoneal macrophages, indicating that hemozoin is able to stimulate monocytes. BH stimulated murine peritoneal neutrophils to express macrophage inflammatory protein-2 (MIP-2), a homologue of human interleukin-8 that is used as a marker of neutrophil activation. Injecting BH into the peritoneal cavity resulted in a dose-dependent migration of neutrophils and a high level of myeloperoxidase activity of peritoneal cells. Finally, BH directly induced neutrophil chemotaxis in vitro. Taken together, these results suggest that the malarial pigment hemozoin can activate leukocytes and may participate in the pathology of severe malaria.

A shift to a peripheral Th2-type cytokine pattern during the carcinogenesis of cervical cancer becomes manifest in CIN III lesions

BACKGROUND

A shifted balance between T helper 1 (Th1)-type and Th2-type cytokines has been hypothesised in cervical dysplasia.

AIMS

To evaluate possible deregulation of the cytokine network by estimating the expression of peripheral cytokines in different stages of cervical disease and in relation to the presence or absence of high risk human papillomavirus (HR-HPV).

METHODS

Twenty one HR-HPV positive women with high grade cervical intraepithelial neoplasia (CIN II-III) and 12 patients with invasive cervical carcinoma formed the study groups. Two control groups consisted of 10 HR-HPV positive and 11 HR-HPV negative women without CIN. Differences in leucocyte subgroups were evaluated by a differential leucocyte count. Plasma concentrations of tumour necrosis factor alpha (TNFalpha), TNFalpha receptors TNFRI and TNFRII, interferon gamma (IFNgamma), interleukin 2 (IL-2), IL-12, IL-4, and IL-10 were determined by enzyme linked immunosorbent assays.

RESULTS

Leucocyte counts in patients with CIN III and carcinoma were significantly higher than in controls. Plasma IFNgamma concentrations were significantly lower in patients with CIN III and carcinoma than in women with CIN II or controls. Plasma concentrations of IL-12, IL-2, IL-4, and TNFalpha did not differ significantly between groups, but significantly lower plasma concentrations of TNFRII were found in CIN III and carcinoma compared with CIN II. IL-10 was detected with increased frequency in the plasma of patients with CIN III and carcinoma.

CONCLUSIONS

These results indicate that a shift to a Th2-type cytokine pattern during the carcinogenesis of cervical cancer occurs in women with CIN III lesions.

The negative immunoregulatory effects of fluoxetine in relation to the cAMP-dependent PKA pathway

Recently, we have shown that various types of antidepressants, including selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, have negative immunoregulatory effects. These antidepressants suppress the interferon-gamma (IFN-gamma)/interleukin-10 (IL-10) production ratio, which is of critical importance for the determination of the capacity of immunocytes to inhibit or activate monocytic/lymphocytic functions. Since cyclic adenosine monophosphate (cAMP) production is stimulated by some antidepressants, and since cAMP inhibits IFN-gamma and stimulates IL-10 production, we postulate that the negative immunoregulatory effects of antidepressants result from their effects on the cAMP-dependent protein kinase A (PKA) pathway. The aim of the present study was to determine whether the negative immunoregulatory effects of fluoxetine may be blocked by antagonists of the cAMP-dependent PKA pathway, such as, e.g., SQ 22536, an adenylate cyclase inhibitor, and Rp-8-Br-cAMPs (Rp-isomer of 8-bromo-adenosine-3',5'-monophosphorothioate), a PKA antagonist. To this end, diluted whole blood collected from 17 normal volunteers was incubated with fluoxetine (10(-6) and 10(-5) M), with or without SQ 22536 (10(-6) and 10(-4) M) and Rp-8-Br-cAMPs (10(-6) and 10(-4) M), afterwards, IFN-gamma, IL-10 and the tumor necrosis factor alpha (TNF-alpha) were determined. Fluoxetine, 10(-6) and 10(-5) M, significantly reduced the production of IFN-gamma and TNF-alpha, and significantly decreased the IFN-gamma/IL-10 production ratio. SQ 22536 and Rp-8-Br-cAMPs were unable to block the suppressant effects of fluoxetine on the IFN-gamma/IL-10 ratio. Rp-8-Br-cAMPs, 10(-4), but not 10(-6) M, normalized the fluoxetine-induced suppression of TNF-alpha production. It is concluded that the suppressant effect of fluoxetine on the IFN-gamma/IL-10 production ratio is probably not related to the induction of the cAMP-dependent PKA pathway, whereas the suppressant effect on TNF-alpha may be related to the induction of PKA. The obtained results suggest that increased activation of the PKA-dependent pathway may constitute an important molecular basis for some (suppression of TNF-alpha production), but not all (suppression of IFN-gamma production), negative immunoregulatory effects of fluoxetine.

Randomized study on the efficacy of cognitive-behavioral therapy for insomnia secondary to breast cancer, part II: Immunologic effects

PURPOSE

Cross-sectional studies suggest that clinical insomnia is associated with immune downregulation. However, there is a definite need for experimental studies on this question. The goal of this randomized controlled study was to assess the effect of an 8-week cognitive-behavioral therapy (CBT) for chronic insomnia on immune functioning of breast cancer survivors. Previous analyses of this study showed that CBT was associated with improved sleep and quality of life, and reduced psychological distress.

PATIENTS AND METHODS

Fifty-seven women with chronic insomnia secondary to breast cancer were randomly assigned to CBT (n = 27) or to a waiting-list control condition (WLC; n = 30). Peripheral-blood samples were taken at baseline and post-treatment (and postwaiting for WLC patients), as well as at 3-, 6-, and 12-month follow-up for immune measures, including enumeration of blood cell counts (ie, WBCs, monocytes, lymphocytes, CD3+, CD4+, CD8+, and CD16+/CD56+) and cytokine production (ie, interleukin-1-beta [IL-1beta] and interferon gamma [IFN-gamma]).

RESULTS

Patients treated with CBT had higher secretion of IFN-gamma and lower increase of lymphocytes at post-treatment compared with control patients. Pooled data from both treated groups indicated significantly increased levels of IFN-gamma and IL-1beta from pre- to post-treatment. In addition, significant changes in WBCs, lymphocytes, and IFN-gamma were found at follow-up compared with post-treatment.

CONCLUSION

This study provides some support to the hypothesis of a causal relationship between clinical insomnia and immune functioning. Future studies are needed to investigate the clinical impact of such immune alterations.

Different profile of cytokine synthesis according to the severity of acute pancreatitis

AIM: To evaluate the cellular synthetic ability of cytokines involved in pro- and anti-inflammatory reactions in patients with AP.

METHODS: Sixty-seven patients with AP (16 severe, 51 mild) and 10 controls were included in the study. Cultures of whole blood were performed in samples obtained within the first 72 h from the onset of pain. Serum levels of interleukins (IL) 6, 8, 10, and TNF-α were measured at baseline and in the supernatant of cultures with (functional reserve) or without stimulation with phytohemaglutinin.

RESULTS: Basal levels of cytokines were significantly higher in patients with severe AP. A significant increase of all pro-inflammatory cytokines vs basal levels was observed in the supernatant after 24 h of whole blood cultures in patients, but not in controls. In contrast, IL-10 increased significantly in the supernatant of cultures only in patients with mild AP. Cells showed a statistically significant functional reserve for all IL in patients with mild, but only for pro-inflammatory cytokines in patients with severe AP.

CONCLUSION: A marked activation of immune system may be observed in patients with AP, being balanced between pro- and anti-inflammatory cytokines in patients with mild but not severe AP. A reduced functional reserve for the synthesis of IL-10 may be observed in patients with severe AP, which might lead to a worst prognosis.

Does cardiac surgery in newborn infants compromise blood cell reactivity to endotoxin?

Introduction

Neonatal cardiac surgery is associated with a systemic inflammatory reaction that might compromise the reactivity of blood cells against an inflammatory stimulus. Our prospective study was aimed at testing this hypothesis.

Methods

We investigated 17 newborn infants with transposition of the great arteries undergoing arterial switch operation. Ex vivo production of the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α), of the regulator of the acute-phase response IL-6, and of the natural anti-inflammatory cytokine IL-10 were measured by enzyme-linked immunosorbent assay in the cell culture supernatant after whole blood stimulation by the endotoxin lipopolysaccharide before, 5 and 10 days after the operation. Results were analyzed with respect to postoperative morbidity.

Results

The ex vivo production of TNF-α and IL-6 was significantly decreased (P < 0.001 and P < 0.002, respectively), whereas ex vivo production of IL-10 tended to be lower 5 days after the operation in comparison with preoperative values (P < 0.1). Ex vivo production of all cytokines reached preoperative values 10 days after cardiac surgery. Preoperative ex vivo production of IL-6 was inversely correlated with the postoperative oxygenation index 4 hours and 24 hours after the operation (P < 0.02). In contrast, postoperative ex vivo production of cytokines did not correlate with postoperative morbidity.

Conclusion

Our results show that cardiac surgery in newborn infants is associated with a transient but significant decrease in the ex vivo production of the pro-inflammatory cytokines TNF-α and IL-6 together with a less pronounced decrease in IL-10 production. This might indicate a transient postoperative anti-inflammatory shift of the cytokine balance in this age group. Our results suggest that higher preoperative ex vivo production of IL-6 is associated with a higher risk for postoperative pulmonary dysfunction.

The inflammatory response to vaccination is altered in the elderly

To further explore whether immune function and acute phase response are altered during ageing, the response to a mild inflammatory stress (DT-Polio-Typhim vaccination) was studied in elderly and young subjects. Cytokine production (IFN-gamma, TNF-alpha, IL-6, IL-10) by whole blood cultures, circulating cytokines and acute phase proteins were analysed before and 2 days after vaccination. Prior to vaccination, only IFN-gamma production was lower in the elderly than in the young subjects due to a lower mononuclear cell number. In the same time, although in the normal range, several acute phase proteins were greater in elderly than in young subjects, suggesting a low-grade inflammatory state in the elderly. After vaccination, IFN-gamma production remained lower in the elderly than in the young, supporting an altered cell-mediated immunity with advancing age. TNF-alpha production was unaffected by either ageing or vaccination. IL-6 production was stimulated by vaccination in young subjects but not significantly in the elderly. IL-10 production was inhibited by vaccination in the elderly but not in the young. Acute phase proteins were less increased in elderly than in young subjects. Taken together, these results support a general lack of inflammatory response in the elderly exposed to an immune challenge and suggest that immune deficiency may concern both Th1 and Th2 responses. However, the interpretation must respect the limitation of small subjects number.

Elevated ex vivo monocyte chemotactic protein-1 (CCL2) in pulmonary as compared with extra-pulmonary tuberculosis

Background

Tuberculosis causes 3 million deaths annually. The most common site of tuberculosis is pulmonary however; extra-pulmonary forms of the disease also remain prevalent. Restriction of Mycobacterium tuberculosis depends on effective recruitment and subsequent activation of T lymphocytes, mononuclear and polymorphonuclear cells to the site of infection. Tumor necrosis factor (TNF)-α is essential for granuloma formation and is a potent activator of monocyte chemotactic protein (MCP-1, CCL2). CCL2 is essential for recruitment of monocytes and T cells and has been shown to play a role in protection against tuberculosis. Interleukin -8 (CXCL8) is a potent activator of neutrophils. Increased levels of CCL2, CXCL8 and TNFα are reported in tuberculosis but their significance in different forms of tuberculosis is as yet unclear. We have used an ex vivo assay to investigate differences in immune parameters in patients with either pulmonary or extra-pulmonary tuberculosis.

Methods

Serum levels of CCL2, CXCL8 and TNFα were measured in patients with pulmonary tuberculosis (N = 12), extra-pulmonary tuberculosis (N = 8) and BCG-vaccinated healthy volunteers (N = 12). Whole blood cells were stimulated with non-pathogenic Mycobacterium bovis bacille-Calmette Guerin (BCG) vaccine strain or bacterial lipopolysaccharide (LPS) and cyto/chemokines were monitored in supernatants.

Results

Circulating serum levels of CXCL8 and TNFα were raised in all tuberculosis patients, while CCL2 levels were not. There was no difference in spontaneous cytokine secretion from whole blood cells between patients and controls. M. bovis BCG-induced ex vivo CCL2 secretion was significantly greater in pulmonary as compared with both extra-pulmonary tuberculosis patients and endemic controls. In response to LPS stimulation, patients with pulmonary tuberculosis showed increased CCL2 and TNFα responses as compared with the extra-pulmonary group. BCG-, and LPS-induced CXCL8 secretion was comparable between patients and controls.

Conclusion

CCL2 is activated by TNFα and is essential for recruitment of monocytes and T cells to the site of mycobacterial infection. Increased CCL2 activation in pulmonary tuberculosis may result in a stronger cellular response as compared with extra-pulmonary tuberculosis patients, and this may contribute to the localization of infection to the pulmonary site.

Association of the risk of osteoarthritis with high innate production of interleukin-1beta and low innate production of interleukin-10 ex vivo, upon lipopolysaccharide stimulation

OBJECTIVE

In a sibpair study of osteoarthritis (OA) patients, we investigated whether, upon stimulation with lipopolysaccharide (LPS), variations in the innate ex vivo production of interleukin-1beta (IL-1beta), IL-1 receptor antagonist (IL-1Ra), IL-10, and tumor necrosis factor alpha (TNFalpha) in whole-blood assays contribute to the risk of OA.

METHODS

Data from 305 patients with OA at multiple sites (hand, knee, hip, and spine), whose median age was 60 years (range 43-79 years), were compared with those from 137 controls. OA was defined in accordance with the American College of Rheumatology criteria. Whole-blood samples were stimulated with LPS (10 ng/ml). In the supernatants, cytokines were measured by enzyme-linked immunosorbent assay. Odds ratios (ORs) were used as measures of the relative risk of OA in relation to quartiles of IL-1beta, IL-1Ra, TNFalpha, and IL-10 production. The ORs were adjusted for sex and age, and 95% confidence intervals (95% CIs) were computed using robust standard errors to take into account the intrafamily effect.

RESULTS

Subjects in the highest quartile of IL-1beta and IL-1Ra had an increased risk of OA (OR 3.3, 95% CI 1.4-7.9 and OR 8.0, 95% CI 3.7-17.4, respectively), while subjects in the lowest quartile of IL-10 had a 3-fold increased risk of OA (OR 3.1, 95% CI 1.5-6.5). High innate ex vivo production of TNFalpha was not associated with an increased risk of OA.

CONCLUSION

Subjects with a high innate ex vivo production of IL-1beta and IL-1Ra and low innate ex vivo production of IL-10 have an increased risk of OA. These results suggest that a proportion of the genetic susceptibility to OA may be encoded for by variations in innate cytokine activity.

Differential cytokine profile in children with cystic fibrosis

The previously observed occurrence of antineutrophil cytoplasmic autoantibodies (ANCA) in patients who have cystic fibrosis (CF), together with the reported decrease in IgG2, a Th1-controlled isotype, suggests a potential for Th1/Th2 imbalance in CF patients with a possible Th2 predominance. 48 CF patients and 16 controls had levels of IFNgamma, IL-4, and IL-10 measured in supernatants of whole blood cell cultures stimulated by lipopolysaccharide (LPS) and phytohemaglutinine (PHA). The patients were divided into 2 groups: "low responders", having negligible secretion of cytokines (IFNgamma: 10.0-200.0 pg/ml, IL-4: 0.0-0.3 pg/ml) and "high responders", producing high levels of both IFNgamma (500.0-2000.0 pg/ml) and IL-4 (1.0-200.0 pg/ml). There was a statistically significant (P < 0.01) deterioration of lung function measured by an FEV(1) decline by 11.2% over 3 years in the "low responder" group. 10 of 16 "low responders" had chronic lung infections with P. aeruginosa while such infection was less prevalent in the "high responder" group where only 13 of 32 CF patients had positive cultures. A shift towards Th2 response was observed in the "high responder" group as children chronically infected with P. aeruginosa had greater IL-4 production than non-infected CF patients within the same cohort. ANCA autoantibodies were found only in the "high responder" group. Th2 immune response predominance in a subset of CF patients is associated with chronic P. aeruginosa infection.

Determination of tumor necrosis factor-α responsiveness in piglets around weaning using an ex vivo whole blood stimulation assay

Ex vivo whole blood stimulation with endotoxin has proved to be a useful method for quantitative evaluations of the pro-inflammatory cytokine tumor necrosis factor alpha (TNF-alpha) response ability in humans. In the present study, a dose- and time-response study was carried out in order to develop an ex vivo whole blood stimulation assay for the quantification of TNF-alpha production in pigs. The TNF-alpha response was enhanced with increasing endotoxin stimulation dose. The maximum TNF-alpha response occurred after 2-8 h of stimulation. Subsequently, the assay was used to evaluate the TNF-alpha response in pigs (n=32) in relation to weaning. The TNF-alpha response was 332 pg ml(-1) (+/-59 pg) plasma 2 days before weaning and 127 pg ml(-1) (+/-23 pg) plasma 2 days after weaning, which was a significant reduction (p<0.001). Total and differential counts of leucocytes were the same before and after weaning. Thus the lower TNF-alpha response may be due to reduced monocyte responsiveness to the endotoxin, rather than caused by a reduction in monocyte numbers. The reduced TNF-alpha response in piglets after weaning may be a factor of importance to the increased disease susceptibility seen in piglets in this period.