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The pathophysiological hallmark of spotted fever group rickettsioses comprises infection of endothelial cells with subsequent infiltration of inflammatory cells. Based on its ability to promote inflammation and endothelial cell activation, we investigated the role of CD40L in African tick bite fever (ATBF), caused by Rickettsia africae, using different experimental approaches. Several significant findings were revealed. 1) Patients with ATBF (n = 15) had increased serum levels of soluble CD40 ligand (sCD40L), which decreased during follow-up. 2) These enhanced sCD40L levels seem to reflect both direct and indirect (through endothelial cell activation involving CX3CL1-related mechanisms) effects of R. africae on platelets. 3) In combination with sCD40L, R. africae promoted a procoagulant state in endothelial cells by up-regulating tissue factor and down-regulating thrombomodulin expression. 4) Although the R. africae-mediated activation of platelets involved TLR2, the combined procoagulant effects of R. africae and sCD40L on endothelial cells involved TLR4. 5) Doxycycline counteracted the combined procoagulant effects of R. africae and sCD40L on endothelial cells. Our findings suggest an inflammatory interaction between platelets and endothelial cells in ATBF, involving TLR-related mechanisms. This interaction, which includes additive effects between sCD40L and R. africae, may contribute to endothelial inflammation and hypercoagulation in this disorder.

Common variable immunodeficiency (CVID) is the most frequent symptomatic primary immunodeficiency disease, characterized by low levels of circulating immunoglobulins and recurrent bacterial infections, particularly of the respiratory tract. T cell dysfunction is often present, and lymphoproliferative and autoimmune disorders as well as haematological cytopenias are frequently observed. In this study, we report a polyclonal expansion of large granular lymphocytes (LGL) in a substantial proportion of CVID patients, associated with splenomegaly, increased numbers of CD8(+) T cells, inverted CD4 : CD8 T cell ratios and neutropenia. CVID patients who had both increased numbers of LGL and granulocytopenia had elevated levels of soluble Fas ligand (sFasL). Our observations indicate that CVID may be added to the list of inflammatory diseases associated with increased numbers of LGL. Furthermore, our findings suggest common pathogenic mechanisms of granulocytopenia in CVID and lymphoproliferative disease of granular lymphocytes.

Transplant-associated coronary artery disease (TxCAD) appears to be initiated by endothelial cell activation and inflammation involving inflammatory cytokines and chemokines. Osteoprotegerin (OPG) and receptor activator of nuclear Factor-kappaB ligand (RANKL) have been implicated in cardiovascular disease progression and we measured the expression of these mediators in serum and myocardial biopsies taken serially during the first year after heart transplantation (HTx), relating them to the development of TxCAD. Serum OPG as well as myocardial gene expression of RANK and OPG, but not RANKL, were highest early after HTx and declined progressively. Importantly, patients who develop TxCAD or experience episodes of acute rejection showed a lower myocardial RANKL expression throughout the first year after transplantation than patients without these complications. Our findings may suggest an unrecognized role RANKL in maintaining myocardial and/or endothelial integrity and suggest that RANKL should be further investigated as a parameter that may predict development of TxCAD.

Objectives: To examine the immune modulating effects of cyclooxygenase type 2 (COX-2) inhibitors (COX-2i) in HIV-infected patients on combination antiretroviral treatment (CART)., Design: In-depth substudy from an approved, open, controlled, randomized study comparing the immune modulating effects of CART in combination with COX-2i after 12 weeks., Methods: Patients (n = 38) on long-term CART with stable viral load (VL) < 50,000 copies/ml and CD4+ T-cell counts > 100/microl were randomized to CART and rofecoxib 25 mg bid (n = 12) or celecoxib 400 mg bid (n = 12), or CART only without placebo (n = 14). Routine clinical chemistry, CD4+ and CD8+ counts and VL were safety parameters. Immunological parameters included C-reactive protein, beta2-microglobulin, Ig isotypes and IgG subclasses as well as several T-lymphocyte subsets. Non-parametric analyses were used throughout., Results: Prestudy experiments showed higher median intracellular expression of COX-2 in CD4+ (P = 0.048) and possibly CD8+ (P = 0.09) T cells from patients on CART compared with uninfected controls. In the clinical study, increased CD4+ T-cell counts were observed only in patients on COX-2i with VL < 50 copies/ml (P = 0.02). Decreased expression of CD38+ on CD8+ T cells and subsets as well as reductions in IgA and IgM (P < 0.03) were most pronounced in patients on COX-2i who had detectable VL (n = 6). COX-2i treatment enhanced the perforin content particularly in the differentiated CD27-/CD8+ T-cell subsets compared with controls (P = 0.05)., Conclusions: COX-2i together with CART improved markers for persistent immune activation, particularly in patients with viraemia, as well as enhanced perforin expression, and thereby strengthened COX-2 as a potential therapeutic target in HIV infection.

Objective: Based on its role in inflammation and matrix degradation, we hypothesized a role for osteoprotegerin (OPG), RANK, and RANK ligand (RANKL) in coronary artery disease., Methods and Results: We examined the expression of various members of the OPG/RANKL/RANK axis in patients with stable and unstable angina and in the atherosclerotic lesions of apolipoprotein E-deficient (apoE(-/-)) mice. Our findings were: (1) Serum levels of OPG were raised in patients with unstable angina (n=40), but not in those with stable angina (n=40), comparing controls (n=20); (2) mRNA levels of RANKL were increased in T-cells in unstable angina patients accompanied by increased expression of RANK in monocytes; (3) strong immunostaining of OPG/RANKL/RANK was seen within thrombus material obtained at the site of plaque rupture during acute myocardial infarction; (4) OPG/RANKL/RANK was expressed in the atherosclerotic plaques of apoE(-/-) mice, with RANKL located specifically to the plaques; and (5) RANKL enhanced the release of monocyte chemoattractant peptide-1 in mononuclear cells from unstable angina patients, and promoted matrix metalloproteinase (MMP) activity in vascular smooth muscle cells., Conclusions: We show enhanced expression of the OPG/RANKL/RANK system both in clinical and experimental atherosclerosis, with enhanced T-cell expression of RANKL as an important feature of unstable disease.

Objective: Increasing data support the involvement of chemokines in atherogenesis. However, although several studies have shown increased chemokine levels in adult patients, the literature is virtually devoid of data on chemokines in children with hypercholesterolemia., Methods and Results: We examined the gene expression of chemokines in peripheral blood mononuclear cells (PBMCs) from clinically healthy children with and without heterozygous familial hypercholesterolemia (FH). Our main findings were: (1) compared with healthy controls, PBMCs from FH children showed significantly higher mRNA levels of RANTES, but not of the other examined chemokines; (2) an opposite pattern was seen in adult FH subjects, with markedly enhanced expression of macrophage inflammatory peptide-1alpha, but not of RANTES; (3) this increased gene expression of RANTES in PBMCs from FH children seemed to reflect enhanced RANTES expression in monocytes but not in T cells; (4) FH children also had raised serum levels of neopterin, additionally suggesting monocyte/macrophage activation in these children; and (5) PBMCs from both FH children and controls showed enhanced release of interleukin 8 on RANTES stimulation in vitro., Conclusions: Our findings support a role of inflammation also in the early stages of atherogenesis possibly involving monocyte-derived RANTES as an important mediator.

Objectives: We sought to determine the relationship between circulating cytokine levels and clinical outcomes in patients with heart failure (HF) following acute myocardial infarction (AMI)., Background: Persistent inflammation plays a role in the development of HF, and various inflammatory cytokines predict cardiovascular events in acute coronary syndromes., Methods: We measured plasma levels of interleukin (IL)-6, monocyte chemotractant protein 1, IL-10, and soluble tumor necrosis factor receptor type 1 (sTNFR1) during longitudinal testing over a period of two years in 234 patients with HF following AMI recruited for participation in the OPTIMAAL trial, focusing on the possible prognostic value of circulating cytokine levels in these patients., Results: Measurement of sTNFR1 at baseline predicted all-cause mortality and cardiovascular death in patients with post-MI HF after adjustment for other biomarkers that have been shown to give prognostic information in HF patients, such as N-terminal B-type natriuretic peptide., Conclusions: Assessment of sTNFR1 levels might provide important prognostic information in patients who develop HF during the acute phase following AMI.

Background: Mannose-binding lectin (MBL) is a soluble receptor of the innate immune system, probably contributing to antimicrobial defence. The possible role of MBL in HIV infection is unclear., Materials and Methods: Peripheral blood mononuclear cells (PBMCs) from 28 HIV-infected patients and 13 healthy controls were stimulated with MBL and costimulated with HIV-1 gp120 or mannan from Saccharomyces cerevisiae before inflammatory responses in PBMC cultures were examined by enzyme-linked immunosorbent assay (ELISA) and flow cytometry. HIV-1 RNA replication in vitro was assessed by quantitative reverse transcription polymerase chain reaction (RT-PCR) in supernatants from patients with measurable HIV-1 RNA levels., Results: (i) Enhanced TNF-alpha responses were observed when PBMCs from healthy controls and HIV-infected patients were stimulated with MBL and costimulated with HIV-1 gp120 or mannan. (ii) MBL stimulation induced increased HIV RNA replication in culture supernatants when costimulated with mannan., Conclusions: The present study suggests a modulatory role of MBL on cytokine responses, and HIV replication after stimulation with microbial products. These effects of MBL on inflammatory responses and viral replication may be clinically relevant for HIV infection.

The importance of the innate immune system, including mannose-binding lectin and the complement system, in common variable immunodeficiency is unclear. The objective of this study was to evaluate mannose-binding lectin and the complement system in relation to clinical and immunological parameters in patients with common variable immunodeficiency. Circulating levels of mannose-binding lectin, complement components, complement activation products and functional capacity of complement pathways were correlated to clinical features within 71 patients and compared with 30 healthy controls. The main findings were; the patients had signs of increased complement activation significantly associated with signs of autoimmunity and immunological hyperactivity; there were no signs of deficiencies of the classical and alternative complement pathways in the patient group; the prevalence of lectin pathway deficiency was the same in patients and controls, but patients with increased frequency of lower respiratory tract infections or bronchiectasis had lower capacity of the lectin pathway than patients without these features (P = 0.002 and 0.004, respectively); the serum concentration of mannose-binding lectin was inversely correlated to the frequency of lower respiratory tract infections (P = 0.002) and bronchiectasis (P = 0.01). We conclude that patients with common variable immunodeficiency have no increased frequency of complement deficiencies but signs of increased complement activation. Our findings suggest that mannose-binding lectin and the lectin complement pathway may protect against lower respiratory tract infection and bronhiectasis in patients with common variable immunodeficiency.

Background: Inflammation and matrix degradation may play a pathogenic role in chronic heart failure (CHF), and therefore, we examined whether thalidomide, a drug with potential immunomodulating and matrix-stabilizing properties, could improve left ventricular (LV) function in patients with CHF secondary to idiopathic dilated cardiomyopathy (IDCM) or coronary artery disease (CAD)., Methods and Results: Fifty-six patients with CHF and an LV ejection fraction (LVEF) <40% who were already on optimal conventional cardiovascular treatment were randomized to thalidomide (25 mg QD increasing to 200 mg QD) or placebo and followed up for 12 weeks. Our main findings were as follows: (1) During thalidomide treatment but not during placebo, there was a marked increase in LVEF (&7 EF units) along with a significant decrease in LV end-diastolic volume and heart rate. (2) This improvement in LVEF was accompanied by a decrease in matrix metalloproteinase-2 without any changes in its endogenous tissue inhibitor, suggesting a matrix-stabilizing net effect. (3) Thalidomide also induced a decrease in total neutrophil count and an increase in plasma levels of tumor necrosis factor-alpha, suggesting both proinflammatory and antiinflammatory effects. (4) The effect of thalidomide on LVEF was more marked in IDCM than in CAD, possibly partly reflecting that the former group was able to tolerate a higher thalidomide dosage., Conclusions: Although our results must be confirmed in larger studies that also examine the effects on morbidity and mortality, our findings suggest a role for thalidomide in the management of CHF in addition to traditional cardiovascular medications.

Background: Numerous studies have demonstrated the ability of oxidized LDL [(ox)LDL] to promote an inflammatory response in macrophages. Several inflammatory mediators have been reported to increase after oxLDL stimulation of such cells, but their relative importance is still unknown. In the present study, we used microarrays to identify genes in THP-1 macrophages that were upregulated by oxLDL., Methods and Results: Our main findings were as follows. In a microarray screening experiment, we identified LIGHT, a ligand in the tumor necrosis factor superfamily, as one of the genes that were markedly upregulated in oxLDL-stimulated THP-1 macrophages. We showed significantly raised plasma levels of LIGHT in patients with stable angina (n=40) and particularly in those with unstable angina (n=40) compared with healthy controls (n=20), which underscores the clinical relevance of the in vitro finding. We also showed that LIGHT enhanced lipid accumulation in oxLDL-stimulated THP-1 macrophages, possibly through upregulation of class A scavenger receptor (SR-A). This increased lipid accumulation was accompanied by enhanced expression of tissue factor and plasminogen activator inhibitor-1, as well as enhanced thrombin formation, transforming macrophages into a prothrombotic phenotype. The LIGHT-mediated increase in SR-A, tissue factor, and plasminogen activator inhibitor-1 was also seen in human monocyte-derived macrophages. Finally, the LIGHT-mediated enhancement of SR-A and TF expression appears to involve nuclear factor-kappaB activation., Conclusions: These findings suggest that LIGHT could serve as a molecular link between lipid metabolism, inflammation, and thrombus formation, which are all features of atherosclerotic plaques.

Several studies have reported enhanced oxidative stress in patients with HIV infection. An important pathophysiologic consequence of increased oxidative stress is endogenous DNA damage, and the base excision repair pathway is the most important mechanism to withstand such deleterious effects. To investigate the role of base excision repair in HIV infection, we examined 7,8-dihydro-8-oxoguanine (8-oxoG) levels as a marker of oxidative DNA damage and DNA glycosylase activities in CD4(+) and CD8(+) T cells of HIV-infected patients and controls. These results showed that the HIV-infected patients, particularly those with advanced disease, had increased levels of 8-oxoG in CD4(+) T cells and marked declines in DNA glycosylase activity for the repair of oxidative base lesions in these cells. In contrast, CD8(+) T cells from HIV-infected patients, with 8-oxoG levels similar to those in healthy controls, showed enhanced capacity to repair oxidative DNA damage. Finally, highly active antiretroviral therapy induced increased glycosylase activity in CD4(+) T cells and normalized 8-oxoG levels. This imbalance between the accumulation of oxidative DNA damage and the capacity to repair such lesions in CD4(+) T cells may represent a previously unrecognized mechanism involved in the numerical and functional impairment of CD4(+) T cells in patients with HIV infection.

Aims: Inflammatory cytokines may play a pathogenic role in heart failure (HF). CD40-CD40 ligand (CD40L) interactions are important in atherogenesis and based on its role in inflammation we sought to evaluate the role of CD40L in human HF., Methods and Results: Serum levels of soluble (s) CD40L were measured in 236 patients with acute HF following myocardial infarction, treated with either angiotensin-converting enzyme (ACE)-inhibition or angiotensin II blockade and followed for 2 years, and in 116 patients with chronic HF. Our main findings were: (i) patients with acute HF had increased sCD40L levels, particularly those with severe HF, diabetes, or hypertension; (ii) when these patients were followed longitudinally, persistently raised sCD40L levels were found throughout the observation period with no effect of captopril or losartan; (iii) the increase in sCD40L during follow-up was not seen in patients receiving warfarin therapy; (iv) patients with chronic HF also had raised sCD40L, significantly correlated with clinical severity, neurohormonal dysregulation, and left ventricular dysfunction; (v) studies from different blood compartments suggest that the vasculature of lower extremities and the failing myocardium itself may produce and secrete sCD40L in chronic HF., Conclusion: Our findings may suggest a pathogenic role for enhanced CD40-CD40L interactions in human HF.

Background: Persistent inflammation appears to play a role in the development of heart failure (HF). Osteoprotegerin (OPG), the receptor activator of nuclear factor-kappaB (RANK), and RANK ligand (RANKL) are newly discovered members of the tumor necrosis factor superfamily that are critical regulators in bone metabolism but appear also to be involved in immune responses. We hypothesized that the OPG/RANK/RANKL axis could be involved in the pathogenesis of heart failure (HF), and this hypothesis was investigated in both experimental and clinical studies., Methods and Results: Our main and novel findings were as follows: (1) In a rat model of postinfarction HF, we found persistently increased gene expression of OPG, RANK, and RANKL in the ischemic part of the left ventricle (LV) and, for OPG, in the nonischemic part that involved both noncardiomyocyte and in particular cardiomyocyte tissue. (2) Enhanced myocardial protein levels of OPG, RANK, and RANKL, in particular, were also seen in human HF, and using immunohistochemistry, we localized these mediators to cardiomyocytes within the LV in both experimental and clinical HF. (3) In human HF, we also found increased systemic expression of RANKL (T cells and serum) and OPG (serum), with increasing levels according to functional, hemodynamic, and neurohormonal disease severity. (4) RANKL increased total matrix metalloproteinase activity in human fibroblasts, which indicates a matrix-degrading net effect and suggests a potential mechanism by which enhanced RANKL expression in HF may contribute to LV dysfunction., Conclusions: These findings suggest a potential role for known mediators of bone homeostasis in the pathogenesis of HF and possibly represents new targets for therapeutic intervention in this disorder.

Background: Living with a chronic disease, such as primary antibody deficiency, will often have consequences for quality of life. Previous quality-of-life studies in primary antibody deficiency patients have been limited to different treatment methods. We wanted to study how adults with primary antibody deficiencies manage their conditions and to identify factors that are conducive to coping, good quality of life and hope., Methods: Questionnaires were sent to all patients > or =20 years of age with primary antibody deficiencies who were served by Rikshospitalet University Hospital. The questionnaires consisted of several standardized scales: Ferrans and Powers Quality of Life Index (QLI), Short Form-36 (SF-36), Jalowiec Coping Scale (JCS), Nowotny Hope Scale (NHS), and one scale we devised with questions about resources and pressures in the past. Of a total of 91, 55 patients (aged 23-76 years) answered the questionnaires. The questionnaire study were supplemented with selected interviews of ten extreme cases, five with low and five with high quality of life scores., Results: Among the 55 patients, low quality of life scores were related to unemployment, infections in more than four organs, more than two additional diseases, or more than two specific occurrences of stress in the last 2-3 months. Persons with selective IgA deficiency had significantly higher QLI scores than those with other antibody deficiencies. An optimistic coping style was most frequent used, and hope values were moderately high. Based on the interviews, the patients could be divided into three groups: 1) low QLI scores, low hope values, and reduced coping, 2) low QLI scores, moderate hope values, and good coping, and 3) high QLI scores, moderate to strong hope values, and good coping. Coping was related to the patients' sense of closeness and competence., Conclusion: Low quality of life scores in adults with primary antibody deficiencies were linked to unemployment and disease-related strains. Closeness and competence were preconditions for coping, quality of life and hope. The results are valuable in planning care for this patient group.

Chemokines, a group of cytokines that attracts and activates leucocyte subpopulations in inflamed tissue, have been associated with the pathogenesis of a number of inflammatory diseases, and some recent reports have suggested their involvement in Wegener's granulomatosis (WG). To elucidate further the possible role of chemokines in WG we examined serum levels of several CC- and CXC-chemokines in WG patients and assessed the ability of corticosteroids to modulate the expression of these mediators in vitro. Our main findings were: (i) WG patients (n = 14) had elevated serum levels of several inflammatory chemokines [i.e. regulated upon activation normal T cell expressed and secreted (RANTES), monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-8] compared to healthy controls (n = 9), as assessed by enzyme immunoassays (EIAs); (ii) by using EIAs and real-time reverse transcription-polymerase chain reaction (RT-PCR), we demonstrated the ability of methylprednisolone (MP) to down-regulate both the spontaneous and the staphylococcal enterotoxin B (SEB)-induced release of chemokines from peripheral blood mononuclear cells (PBMC) in vitro in both WG patients and controls, possibly involving both transcriptional and post-transcriptional mechanisms; and (iii) the ability of MP to attenuate chemokine secretion was less pronounced in WG patients than in controls, particularly with regard to inhibition of spontaneous release. Our findings suggest a role for chemokines in the pathogenesis of WG. The diminished MP-mediated suppression of chemokines in PBMC from WG patients suggests that more specific modulators of chemokine levels should be investigated in this disorder.

Objective: This article compares preference-based utilities from the multiattribute utility instrument 15D with those derived from the EQ-5D and the Short Form 36 (SF-6D) in patients with HIV/AIDS. In particular, we wanted to examine if the finer descriptive system of the 15D would result in better discriminative capacity or responsiveness., Methods: In a prospective observational study of 60 Norwegian patients with HIV/AIDS from two hospitals, the authors compared scores, assessed associations with disease staging systems, and assessed test-retest reliability and responsiveness of the instruments., Results: On average, the 15D gave higher utility scores than the other two measures, the mean utility scores were: 15D--0.86, SF-6D--0.73, and EQ-5D Index--0.77. Test-retest reliability was acceptable for all measures, with intraclass correlation coefficients between 0.78 and 0.94. The correlation between scores of the 3 scales was substantial (p = 0.74-0.80). There was no major difference in responsiveness between the measures., Conclusions: The different measures gave different utility values in this sample of patients with HIV/AIDS, although many of the measurement properties were similar. There was no evidence for better discriminative capacity or responsiveness for the 15D, than for the two other multiattribute measures.

Common variable immunodeficiency (CVID) is characterized by low levels of circulating immunoglobulins, leading to frequent infections, particularly of the respiratory tract. Frequently, T-cell abnormalities are observed. Interleukin-7 (IL-7) is involved in the homeostasis of lymphocytes, and may be elevated in lymphopenia. Mutations of genes related to IL-7 may lead to severe immunodeficiency disorders. We report elevated plasma levels of circulating IL-7 in a subgroup of CVID. These patients have increased numbers of circulating CD8+ T cells with decreased apoptosis and a predominance of CC chemokine receptor 7- (CCR7-) effector-memory T cells. Moreover, in some of these patients there is impaired response to IL-7 as assessed by in vitro proliferation and secretion of interferon gamma and transforming growth factor beta. These findings suggest novel pathogenic mechanisms and specific targets for further research in CVID.

Interleukin (IL)-10 may have a therapeutic potential in atherosclerosis, but its mechanisms of action have not been clarified. Foam cell formation is a key event in atherogenesis, and apoptosis of these lipid-laden cells may promote plaque destabilization. We sought to explore whether IL-10 could have plaque-stabilizing properties in acute coronary syndromes (ACS). We studied the effect of IL-10 on oxidized low density lipoprotein (oxLDL)-stimulated THP-1 cells and monocyte-derived macrophages from ACS patients and healthy controls using different experimental approaches. Our main findings were: i) IL-10 enhances lipid accumulation in oxLDL-stimulated THP-1 macrophages, at least partly by counteracting oxLDL-induced apoptosis; ii) This antiapoptotic effect of IL-10 involves increased expression of the antiapoptotic genes Bfl-1 and Mcl-1, accompanied by protective effects on mitochondria function; iii) By silencing Bfl-1 and Mcl-1 genes using siRNAs, we were able to abolish this IL-10-mediated effect on lipid accumulation; iv) IL-10 also induced lipid accumulation in oxLDL-stimulated macrophages from patients with ACS, but not in macrophages from healthy controls; v) In ACS patients, this enhancing effect of IL-10 on lipid accumulation was accompanied by enhanced Mcl-1 expression. No such antiapoptotic effect was seen in macrophages from healthy controls. These findings suggest a new mechanism for the effect of IL-10 in atherosclerosis, possibly contributing to plaque stabilization.

Platelets may act as inflammatory cells. To study the effects of soluble and cell-bound platelet factors on the expression of several cytokines and related mediators in leukocytes, peripheral blood mononuclear cells (PBMC) were incubated with platelet-free supernatants from SFLLRN-activated platelet-rich plasma (PRP) or SFLLRN-activated PRP in itself. Our main findings were: (i) the gene expression of several chemokines and some cytokines were markedly increased by both activated PRP and supernatants, as also confirmed at the protein level for IL-6, IL-8 and MIP-1alpha; (ii) the selective protein kinase A type I (PKAI) antagonist Rp-8-Br-cAMP reduced this platelet-induced expression of IL-6, IL-8 and MIP-1alpha in PBMC, suggesting a role of cAMP/PKAI mediated mechanisms in this interaction; (iii) PGE(2) dose-dependently increased the release of IL-6, IL-8 and MIP-1alpha from PBMC mimicking the effect of activated platelets. Furthermore, activated platelets released comparable amounts of PGE(2), suggesting that platelet-derived PGE2 could interact with PBMC in co-cultures; (iv) IL-10 inhibited the platelet-inducing effect on IL-6, IL-8 and MIP-1alpha in PBMC, and notably, the addition PGE2 totally abolished this IL-10 effect suggesting that the suppressive effect of IL-10 on the plateletinduced activation of PBMC might at least partly involve PGE(2) related mechanisms. The present study supports a view of platelets as inflammatory cells, and suggests a potential role of platelet-derived PGE(2) in platelet-induced inflammatory responses.

Background: Enhanced activity of matrix metalloproteinases (MMPs) has been reported to have a pathogenic role in several diseases such as cancer and cardiovascular disorders, and seems also to play a part in certain autoimmune diseases., Objective: To examine whether enhanced MMP activity may also have a role in the pathogenesis of Wegener's granulomatosis (WG)., Methods: In a study group of 15 patients with WG and 15 controls, plasma levels and gene expression were measured in freshly isolated peripheral blood mononuclear cells (PBMCs) of several MMPs and their endogenous inhibitors (that is, tissue inhibitors of metalloproteinases (TIMPs)) by enzyme immunoassays and RNase protection assay, respectively., Results: Whereas patients with WG in remission had enhanced gene expression of several MMPs and TIMPs in PBMCs, those with active disease had a selective up regulation of MMP-2 and MMP-8 compared with healthy controls, and a down regulation of TIMP-1 and TIMP-3 compared with other patients with WG. Moreover, plasma levels of TIMP-1 and MMP-8 correlated significantly with C reactive protein levels, further supporting an association between activation of the MMP/TIMP system and disease activity in WG. Finally, these changes in MMP/TIMP expression in WG were accompanied by increased total MMP activity in PBMC supernatants, particularly in those with active disease, suggesting a matrix degrading net effect., Conclusion: These findings suggest that disturbed MMP and TIMP activity has a role in the pathogenesis of WG.

Common variable immunodeficiency (CVID) represents a heterogeneous group of antibody deficiency syndromes, characterized by defective antibody production in which T cell deficiency may play a pathogenic role. A subgroup of CVID patients has impaired in vitro T cell proliferation. Using microarray analyses of T cells from these patients, we found a gene expression pattern different from healthy controls and patients with X-linked agammaglobulinaemia. The profile of the differentially expressed genes suggests enhanced cytotoxic effector functions, antigen experienced or chronically activated T cells and a predominance of CCR7(-) T cells. Further experiments using flow cytometry revealed a striking predominance of CCR7(-) T cells in a subgroup of CVID patients, and an association with impaired T cell proliferation. Our observations indicate that a predominance of CCR7(-) T cells with effector-memory cell features and with reduced proliferative capacity may characterize a subgroup of CVID.

Background: Highly active antiretroviral therapy (HAART) often leads to a dramatic improvement in clinical, viral and immunologic parameters in HIV-infected individuals. However, the emergence of long-term side-effects of HAART and in particular dylipidaemia is increasingly reported. Based on the potential lipid-lowering and immunomodulatory properties of tetradecylthioacetic acid (TTA) we examined whether TTA in combination with dietary intervention could modify lipid levels in peripheral blood in HIV-infected patients on HAART., Materials and Methods: Ten HIV-infected patients on protease inhibitor-based HAART with hyperlipidaemia followed a cholesterol-lowering diet throughout the study period (8 weeks). During the last 4 weeks of the study all patients received TTA (1 g qd) in addition to the cholesterol-lowering diet., Results: Our main and novel findings were: (i) TTA in combination with dietary intervention reduces total cholesterol, LDL cholesterol, triglycerides and LDL/HDL cholesterol in these patients, and a particularly suppressing effect was observed during the TTA phase regarding total cholesterol. (ii) During the TTA phase, the cholesterol-lowering effect was accompanied by a significant reduction in plasma levels of tumour necrosis factor alpha. (iii) Our studies in peripheral blood mononuclear cells from these patients and in the liver from wild-type mice receiving TTA suggest that the hypolipidaemic effects of TTA may involve up-regulation of scavenger and LDL-receptor expression., Conclusions: Although few patients were studied, the present pilot study suggests that TTA combined with dietary intervention could be an interesting therapeutic approach in HIV-infected patients on HAART, potentially resulting in both hypolipidaemic and anti-inflammatory effects.

Toll-like receptor 2 (TLR2) stimulation in monocytes may contribute to enhanced inflammation and viral replication in HIV infection. In the present study we examined if TLR2 stimulation could modulate chemokine responses in peripheral blood mononuclear cells (PBMC) from HIV-infected patients and healthy controls. Our main findings were, with similar qualitative patterns in both healthy controls and HIV-infected patients: (1) TLR2 stimulation induced up-regulation of several chemokines at the mRNA level as well as increased protein levels of macrophage inflammatory protein (MIP)-1alpha, interleukin (IL)-8 and regulated on activation, normal T cell expressed and secreted (RANTES); (2) TLR2 stimulation induced enhanced protein expression of CCR5 (a receptor for MIP-1alpha and RANTES) on monocytes; (3) In vitro stimulation with RANTES induced release of MIP-1alpha, MCP-1, IL-8 and interferon-gamma from PBMC. While increased levels of beta-chemokines possibly have antiviral effects, TLR2 stimulation may also promote a chemokine-driven inflammatory loop, potentially contributing to the immunopathogenesis of HIV infection.

Background: Inflammatory processes seem to be involved in pulmonary arterial hypertension (PAH). CD40 ligand (L) may promote inflammation and thrombus formation, and we hypothesized that CD40L could be involved in the pathogenesis of PAH., Methods and Results: Several significant findings were revealed when examining the possible role of CD40L in PAH. (1) Patients with primary (n=13) and secondary (n=11) PAH but not those with chronic thromboembolic pulmonary hypertension (n=8) had increased plasma levels of soluble (s) CD40L compared with control subjects (n=8). (2) PAH patients using warfarin had markedly lower sCD40L levels than those without such therapy. (3) sCD40L levels were higher in arterial (femoral artery) compared with mixed venous blood (pulmonary artery), suggesting enhanced release or reduced clearance in the pulmonary vasculature. (4) Platelets from PAH patients showed enhanced spontaneous and SFLLRN-stimulated release of sCD40L compared with control subjects. (5) In vitro, recombinant sCD40L induced monocyte chemoattractant protein (MCP)-1 and interleukin-8 gene expression in endothelial cells, and plasma levels of these chemokines were raised in all PAH groups, significantly correlated to sCD40L and hemodynamic parameters. (6) Although prostacyclin therapy (3 months) showed clinical benefit, this therapy had no effect on sCD40L and increased MCP-1 levels in PAH patients, and prostacyclin enhanced MCP-1 in CD40L-stimulated endothelial cells., Conclusions: Our findings suggest a role for CD40L in the pathogenesis of PAH, possibly operating through an interaction between platelets and endothelial cells involving chemokine-related mechanisms.

Objectives: We sought to investigate whether activin A could be involved in the immunopathogenesis of acute coronary syndromes., Background: Inflammatory mechanisms seem to play a pathogenic role in atherosclerosis and acute coronary syndromes, but the actual mediators have not been fully identified. Activin A, a pleiotropic member of the transforming growth factor-beta cytokine family, has recently been suggested to play a role in inflammation., Methods: We examined the role of activin A and its endogenous inhibitor follistatin in patients with stable (n = 26) and unstable angina (n = 20) and healthy control subjects (n = 20) by different experimental approaches., Results: 1) Patients with stable angina had raised activin A concentrations, as assessed by protein levels in serum and messenger ribonucleic acid levels in peripheral blood mononuclear cells (PBMCs). 2) Although several activin A-related mediators were upregulated in PBMCs from patients with stable angina compared with controls (i.e., activin A and Smad3), no changes or even downregulation (i.e., Smad2) were seen in unstable disease. 3) The activin type II receptors, representing the primary ligand-binding proteins, were downregulated in unstable compared with stable angina. 4) Percutaneous coronary intervention induced a decrease in the activin A/follistatin ratio, suggesting downregulatory effects on activin A activity. 5) Although activin A dose-dependently suppressed the release of inflammatory cytokines from PBMCs in angina patients, an opposite effect was found in healthy controls., Conclusions: Our findings suggest an anti-inflammatory potential of activin A in angina patients, and such effects may be of particular relevance in unstable angina in which several of the activin parameters were downregulated.

Background: Toll-like receptors (TLRs) are key pattern-recognition receptors of the innate immune system, but their role in human immunodeficiency virus (HIV) infection is largely unknown., Methods: In the present study, we examined the expression of TLR2 and TLR4 on monocytes from 48 HIV-infected patients and 21 healthy control subjects by flow cytometry., Results: We found that freshly isolated monocytes from HIV-infected patients displayed enhanced expression of TLR2 but not TLR4, that TLR2 expression on the surface of monocytes was significantly increased upon stimulation of HIV type 1 envelope protein gp120, and that TLR2 stimulation in HIV-infected patients induced increased viral replication and TNF- alpha response., Conclusion: Our findings suggest potential roles for TLR2 in chronic immune activation and viral replication in HIV infection.

Background: Inflammation is important in atherogenesis. Interleukin (IL)-1 is the prototypic inflammatory cytokine. We hypothesized a dysbalance between inflammatory and anti-inflammatory mediators in the IL-1 family in coronary artery disease (CAD) and a possible modulation of these mediators by HMG-CoA inhibitors (statins)., Methods and Results: In a microarray screening experiment examining peripheral blood mononuclear cells (PBMCs) from 6 CAD patients and 4 healthy control subjects, IL-1beta was identified as 1 of 25 genes whose expression were upregulated in CAD and downregulated by statins. In the following, we studied the role of IL-1beta and related mediators in CAD. Our major findings were as follows. (1) Although mRNA levels of IL-1alpha and IL-1beta were markedly reduced in PBMCs from CAD patients after 6 months of simvastatin (20 mg/d, n=15) and atorvastatin (80 mg/d, n=15) therapy, the reduction in IL-1 receptor antagonist (IL-1Ra) was more modest. Statins also reduced the spontaneous release of IL-1beta and IL-1Ra from PBMCs in CAD patients. (2) mRNA levels of IL-1alpha, IL-1beta, and IL-1Ra were increased in PBMCs from patients with stable (n=20) and unstable (n=20) angina compared with healthy control subjects (n=15). Although the unstable patients had particularly high levels of IL-1beta and IL-1alpha, IL-1Ra was not correspondingly increased. (3) IL-1beta induced release of proatherogenic cytokines from PBMCs, whereas atorvastatin partly abolished this effect., Conclusions: Our findings suggest that cytokines in the IL-1 family may represent therapeutic targets in CAD. The ability of statins to modulate these cytokines in an anti-inflammatory direction underscores their immunomodulatory potential.

Background: Although modulation of inflammatory processes has been suggested as a new treatment modality in heart failure (HF), our knowledge about abnormalities in the cytokine network during HF is still limited. On the basis of a previous cDNA array study examining peripheral blood mononuclear cells from HF patients, we hypothesized a role for activin A, a member of the transforming growth factor (TGF)-beta superfamily, in the pathogenesis of HF., Methods and Results: This study had 4 main and novel findings. First, serum levels of activin A were significantly elevated in patients with HF (n=86) compared with healthy control subjects (n=20), with increasing levels according to disease severity as assessed by clinical, hemodynamic, and neurohormonal parameters. Second, compared with control subjects, HF patients, as determined by real-time quantitative reverse transcriptase polymer chain reaction, also had markedly increased gene expression of the activin A subunit activin betaA in T cells but not in monocytes. Third, in a rat model of HF, we demonstrated a concerted induction of the gene expression of activin betaA and activin receptors IA, IB, IIA, and IIB after myocardial infarction. Immunohistochemical analysis localized activin A solely to cardiomyocytes. Finally, activin A markedly increased gene expression of mediators involved in infarction healing and myocardial remodeling (ie, atrial natriuretic peptide, brain natriuretic peptide, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1, transforming growth factor-beta1, and monocyte chemoattractant protein-1) in neonatal rat cardiomyocytes., Conclusions: Together with our demonstration of activin A-induced gene expression in neonatal cardiomyocytes of mediators related to myocardial remodeling, the expression pattern of activin A during clinical and experimental HF suggests an involvement of this cytokine in the pathogenesis of HF.

Background: Xigris (recombinant human activated protein C) has recently been introduced as a treatment for severe sepsis following a large multicentre trial (the PROWESS trial)., Material and Methods: Critical review of the original paper, follow-up studies and commentaries, and subgroup analyses from the US Food and Drug Administration., Results: Changes in trial design after the start of the trial as well as inconsistent results in two phases of the trial make interpretation difficult. The overall trial results indicate a small benefit from treatment with activated protein C. However, subgroup analysis reveals that several groups of patients appeared to have little benefit. The drug may have severe and potentially lethal side effects in some patients., Interpretation: Although activated protein C may have beneficial effects in some patients with severe sepsis, the effect on different subgroups of patients remains to be clarified. We conclude that there is at present insufficient documentation for a recommendation of activated protein C in patients with severe sepsis.

Objective: Cytokines seem to play a critical role in HIV infection. The cAMP/protein kinase A (PKA) type I pathway is shown to be hyper-activated and contributes to T-cell immune dysfunction in HIV infection. Here, we analysed firstly the levels of cytokine gene expression in unstimulated CD3+T cells from HIV-infected patients on HAART, and secondly the regulation of cytokine and cytokine-related genes by cAMP agonist and antagonist in anti-CD3 activated T cells in order to understand their effects on cytokine networks., Methods: Cytokine Macro Array and real-time RT-PCR techniques were used to study cytokine gene expression in T cells of HIV-positive patients., Results: Of the cytokine-related genes analysed 45% were expressed at twofold or higher levels in unstimulated T cells from HIV-infected patients as compared with healthy controls, and one-third of these genes were hypo-responsive upon activation as compared with controls. Furthermore, cAMP modulated levels of expression of a number of cytokine-related genes differently in patient and control T cells. CXCR4, CCR5 and amphiregulin were up-regulated by cAMP agonist, whereas other cytokine-related genes including macrophage inflammatory protein 1 beta, tumour necrosis factor-alpha and lymphotoxin-beta were markedly down-regulated by cAMP agonist in T cells from both HIV-infected patients and controls. Moreover, members of the chemokine/chemokine receptor family were over-represented among genes regulated by cAMP agonist/antagonist in patient T cells., Conclusions: Our data indicate that T cells from HIV-infected patients are in a pre-activated state and that a set of cytokine genes is hypo-responsive to activation and under tonic regulation by cAMP in these T cells.

Earlier findings have suggested that the balance between interleukin-10 and tumor necrosis factor alpha levels in serum may influence the outcome of cytomegalovirus infection in renal transplant recipients. Therefore, the aim of the present study was to investigate whether human cytomegalovirus induces interleukin-10 production in macrophages. Experiments using human cytomegalovirus (strain 2006), ultraviolet-inactivated cytomegalovirus, and mock-infected differentiated THP-1 cells with or without ganciclovir or monoclonal anti-tumor necrosis factor alpha antibodies were performed. Cytomegalovirus-infected cells produced significantly higher levels of human interleukin-10 mRNA and interleukin-10 than ultraviolet-inactivated cytomegalovirus or mock-infected cells. The addition of ganciclovir had little effect on interleukin-10 production. Anti-tumor necrosis factor alpha antibodies appeared to reduce the interleukin-10 levels. In conclusion, human cytomegalovirus infection of macrophages induces production of human interleukin-10. This requires viral entry, but not full viral replication.

Objective: Increasing evidence supports a role for inflammation in chronic heart failure (CHF). However, the source and the mechanism for this immune activation are unknown. To address this issue we investigated the gene expression of cytokines and the surface expression of activity markers in T-cells and monocytes from CHF patients and healthy controls., Methods: Gene expression of cytokines was analysed by real-time RT-PCR and activation markers by flow cytometry in 14 CHF patients and nine healthy controls. Surface expression of activation markers for T-cells and monocytes were analysed by flow cytometry., Results: T-cells from CHF patients showed enhanced gene expression of chemokines, ligands in the tumor necrosis factor superfamily, as well as the inflammatory cytokines interferon-gamma and interleukin-18 with similar pattern in ischemic (n=5) and idiopathic cardiomyopathy (n=9). In contrast, no differences in cytokine gene expression were found comparing monocytes from CHF patients and controls. Moreover, T-cells from CHF patients had enhanced surface expression of the activation markers CD69 and CD25, while there was no upregulation of the monocyte activation marker CD32 in these patients., Conclusion: T-cells may be a part of the inflammatory response during CHF independent of the etiology of the disorder. Intervention preventing unwanted T-cell activation could represent a new target in the treatment of CHF.

Long-term success of cardiac transplantation is mainly limited by the development of transplant coronary artery disease (CAD); it is generally accepted that it is immune mediated, involving cytokines and growth factors. We show that development of transplant CAD is associated with a particular cytokine profile in myocardial biopsies characterized by a late (i.e., 1 year) increase in tumor necrosis factor-alpha and interferon-gamma gene expression, which precede and potentially contribute to the development of allograft vasculopathy, further supporting a role for inflammation and the pathogenesis of transplant CAD in humans.

Oxidative stress has been implicated in the pathogenesis of human immunodeficiency virus (HIV) infection. We examined the effect of highly active antiretroviral therapy (HAART) on plasma levels of several antioxidants and intracellular glutathione-redox status in CD4+ T cells, in 20 HIV-infected patients. HAART was accompanied by both an improvement of glutathione-redox status and an increase in levels of antioxidant vitamins, without full normalization. Glutathione supplementation in vitro increases T cell proliferation and suppresses the spontaneous release of tumor necrosis factor-alpha from peripheral blood mononuclear cells, in HIV-infected patients receiving HAART. Our findings suggest that therapeutic intervention aimed at normalization of oxidative disturbances in HIV infection could be of interest, in addition to HAART.

Background: Atherogenesis and plaque destabilization involve immune-mediated mechanisms, but the actual mediators have not been fully clarified. Interleukin (IL)-7 is a regulator of T-cell homeostasis but also may be involved in inflammation. We hypothesized that IL-7 could be involved in the inflammatory processes observed in atherosclerosis and acute coronary syndromes., Methods and Results: To study the role of IL-7 in coronary artery disease, we analyzed IL-7 levels and the effect of this cytokine on inflammatory mediators in patients with stable and unstable angina and in healthy control subjects. Our major findings were (1) Plasma levels of IL-7 were significantly increased in patients with stable (n=30) and unstable angina (n=30) comparing healthy control subjects (n=20), particularly in those with unstable disease. (2) Increased release from activated platelets appeared to be a major contributor to the raised IL-7 levels in patients with angina. (3) IL-7 enhanced the expression of several inflammatory chemokines in peripheral blood mononuclear cells from both healthy control subjects and patients with angina, particularly in those with unstable disease. Similar effects were seen in monocytes but not in T cells. (4) MIP-1alpha further increased the release of IL-7 from platelets in a dose-dependent manner. (5) Aspirin reduced both the spontaneous and the SFLLRN-stimulated release of IL-7 from platelets, and when administered to healthy control subjects for 7 days (160 mg qd), it reduced plasma levels of IL-7., Conclusions: Our findings suggest a role for IL-7-driven inflammation in atherogenesis and the promotion of clinical instability in coronary artery disease involving interactions between platelets, monocytes, and chemokines.

Common variable immunodeficiency (CVID) is a heterogeneous group of B cell deficiency syndromes. T cell abnormalities are present in a high proportion of patients with CVID, suggesting impaired T cell-mediated stimulation of B cells. Based on the importance of IL-10 for B cell function and the involvement of the cAMP/protein kinase A type I (PKAI) system in IL-10 synthesis, we examined IL-10 secretion in T cells from CVID patients and controls, particularly focusing on possible modulatory effects of the cAMP/PKAI system. Our main findings were: 1) anti-CD3 and anti-CD3/anti-CD28 activated T cells from CVID patients secreted less IL-10 than healthy controls. This defect was not related to varying proportions of T cell subsets (e.g., CD4(+)/CD8(+), CD45RA(+)/RO(+), or CD28(-) T cells); 2) PKAI activation through the cAMP agonist 8-CPT-cAMP markedly inhibited IL-10 secretion from T cells through CD3 and CD28 activation in both patients and controls, but the sensitivity for cAMP-dependent inhibition was increased in CVID; 3) selective PKAI inhibition by Rp-8-Br-cAMPS markedly increased IL-10 secretion in anti-CD3 and anti-CD3/anti-CD28-stimulated T cells in both patients and controls. Even at the lowest concentrations of Rp-8-Br-cAMPS, IL-10 secretion in CVID patients reached levels comparable to those in controls. Our findings suggest impaired secretion of IL-10 by T cells from CVID patients, suggesting a possible link between T cell deficiency and impaired B cell function in CVID. The involvement of the cAMP/PKAI system in this defect suggests a novel target for therapeutic immunomodulation in CVID.

To gain further insight into the possible role of interleukin (IL)-18 in HIV-1 infection we examined serum levels of IL-18 in various clinical and immunological stages of HIV-1 infection during cross-sectional (n = 41) and longitudinal testing (n = 20) and during HAART (n = 21, 24 months follow-up). Our main findings were that HIV-1-infected patients had significantly raised IL-18 levels comparing healthy controls, particularly in those with advanced disease, that while HAART induced a marked decline in IL-18, virological treatment failure was associated with persistently raised IL-18 levels during such therapy and that our in vitro experiments showed an IL-18-mediated up-regulation of the HIV-1 coreceptor CXCR4 and the pro-apoptotic mediator TRAIL in PBMC from HIV-1-infected patients receiving HAART. HIV-1 infection appears to be characterized by persistently raised IL-18 levels and during HAART, such a pattern was associated with virological treatment failure, possibly contributing to immunodeficiency and HIV-1 replication in these patients.

Objectives: We sought to investigate whether the activation of the chemokine network observed in patients with coronary artery disease (CAD) could be modified by treatment with 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins)., Background: Chemokines and chemokine receptors are important mediators in atherogenesis, and we hypothesized that the statins could affect the chemokine network in CAD., Methods: Thirty CAD patients without previous statin therapy were randomized to receive atorvastatin (80 mg/day, n = 15) or simvastatin (20 mg/day, n = 15). Peripheral blood mononuclear cells (PBMCs) and plasma were obtained at baseline and after six months of statin therapy. Messenger ribonucleic acid (mRNA) expression of chemokines and chemokine receptors in PBMCs was analyzed by ribonuclease protection assay and real-time reverse-transcription polymerase chain reaction. Chemokines were also examined in the supernatants from unstimulated and lipopolysaccharide-stimulated PBMCs (and in plasma)., Results: Our main findings were: 1) gene expression of several chemokines (i.e., macrophage inflammatory protein [MIP]-1alpha, MIP-1beta, and interleukin [IL]-8) and chemokine receptors (i.e., CC chemokine receptor [CCR]1, CCR2, CCR4, and CCR5) was markedly increased among CAD patients compared with healthy control subjects; 2) treatment with atorvastatin and simvastatin markedly reduced the mRNA levels of some of these chemokines (i.e., MIP-1alpha, MIP-1beta, IL-8) and receptors (i.e., CCR1 and CCR2), with the most pronounced effect in the atorvastatin group; and 3) statin therapy reduced the spontaneous release of IL-8 and MIP-1alpha from PBMCs in CAD patients., Conclusions: This study demonstrates a down-regulatory effect of statins on the chemokine network in CAD patients, possibly contributing to the beneficial effects of statins in this disorder.

Background: 3-thia fatty acids such as tetradecylthioacetic acid (TTA) are modified fatty acids that have been suggested to change the plasma profile from atherogenic to cardio protective. Because of its interaction with peroxisome proliferator activated receptor (PPAR) we hypothesized that TTA also could have immunomodulatory properties. Based on the suggested role of inflammation in atherogenesis, any immunomodulating effects of TTA would be of particular interest for the potential use of this fatty acid in atherosclerotic disorders., Materials and Methods: We examined if TTA could modulate proliferation and the release of cytokines from peripheral mononuclear cells (PBMCs) taken from five healthy blood donors., Results: Our main findings were: (i) TTA had several effects on cytokine release from activated PBMCs with a marked increase in interleukin (IL)-10 accompanied by a reduction in IL-2 possibly favouring anti-inflammatory net effects. (ii) These cytokine-modifying effects were found in both T cells and monocytes when cultured separately. (iii) Tetradecylthioacetic acid increased the cytokine stimulating effects of tumour necrosis factor alpha with a particularly enhancing effect on IL-10. (iv) Tetradecylthioacetic acid significantly suppressed PBMC proliferation, and this antiproliferative property did not involve enhanced apoptosis or necrosis. (v) These immunomodulatory effects of TTA were accompanied by a marked down-regulation of PPARoad mRNA expression, the most abundant PPAR subtype in PBMCs., Conclusions: Our findings show potent immunomodulatory effects of TTA in activated PBMCs, possibly involving PPAR-related mechanisms.

To gain insight into the possible role of mannose-binding lectin (MBL) in HIV infection, we analyzed serum levels and the functional complement activation capacity of MBL in different clinical stages of HIV infection during cross-sectional analysis (n = 62) and longitudinal testing (n = 23) as well as during highly active antiretroviral therapy (HAART) (n = 40). The results were correlated with serum levels of C-reactive protein (CRP). Our main findings were as follows. MBL levels and the capacity of complement activation by the MBL pathway were increased in HIV-infected patients with advanced clinical disease as shown in both cross-sectional analysis and longitudinal testing. There was no "normalization" of these parameters during HAART. In fact, MBL levels increased during therapy, and this increase was associated with a good virologic response. Although both MBL and CRP are regarded as acute-phase proteins, no correlation was seen between these proteins. Thus, the notably diverse patterns of MBL responses among patients with different clinical courses and treatments suggest that MBL and complement activation by the MBL pathway could be involved in the pathophysiology of HIV infection. It is not inconceivable that the net effects of MBL responses may vary in different clinical settings.

CXC-chemokines may be involved in atherogenesis. Herein we examined the possible role of CXC-chemokines in the inflammatory interactions between oxidized (ox-) low-density lipoprotein (LDL), platelets and peripheral blood mononuclear cells (PBMC) in 15 patients with coronary artery disease (CAD) without 'traditional' risk factors and 15 carefully matched controls. Our main findings were: (a) ox-LDL stimulated the release of the CXC-chemokines interleukin (IL)-8, ENA-78 and GRO-alpha from PBMC, particularly in CAD. (b) In platelets, ox-LDL induced release of ENA-78 and, when combined with SFLLRN, also of GRO-alpha, with significantly higher response in CAD. (c) Platelet-rich plasma, especially when costimulated with ox-LDL, enhanced the release of IL-8 from PBMC, particularly in CAD patients. (d) Freshly isolated PBMC showed markedly increased IL-8 mRNA expression in CAD patients. Our findings suggest enhanced inflammatory interactions between ox-LDL, platelets and PBMC in CAD patients involving CXC-chemokine related mechanisms, possible contributing to atherogenesis in these and other CAD patients.

Objectives: In the present study, we investigated the effects of statins on serum levels of soluble CD40 ligand (sCD40L) in patients with familial hypercholesterolemia (FH)., Background: Atherosclerotic disease seems to involve inflammatory and immunologic mechanisms, and sCD40L has recently been identified as one of the key players in the atherosclerotic process. HMG-Co A reductase inhibitors, statins, have been recognized as immunomodulators and reduce cardiovascular events and mortality, but the effects of statins on sCD40L has not been clarified., Methods: In a randomized, double-blind, clinical trial, as part of the Atorvastatin versus Simvastatin on Atherosclerosis Progression (ASAP) trial, 110 patients with FH were given atorvastatin 80 mg/daily (n = 57) or simvastatin 40 mg/daily (n = 53) for two years., Results: Our main findings were: 1) at baseline patients with FH had significantly higher (approximately 27-fold) serum levels of sCD40L than healthy controls; 2) statin therapy markedly decreased serum levels of sCD40L (approximately 40% reduction); 3) this decrease in sCD40L was found during both "aggressive" (i.e., atorvastatin) and "conventional" (i.e., simvastatin) statin therapy and was not correlated with the degree of reduction in cholesterol levels., Conclusions: Our findings may suggest enhanced CD40L-CD40 interaction in FH and that this inflammatory response may be downregulated by statins.

Background: Most heart transplant (HTx) recipients develop hypertension, characterized by increased peripheral vascular tone and endothelial dysfunction. Reduced levels of nitric oxide (NO) have been found in essential hypertension, and herein we investigated the possible role of altered concentrations of NO in posttransplant hypertension., Methods: Plasma levels of the NO-derived end products NO2(-) + NO3(-), the endogenous inhibitor of NO synthase asymmetric dimethylarginine (ADMA), and the inflammatory cytokine tumor necrosis factor (TNF)-alpha were examined in 65 stable hypertensive long-term (6 years [range 1-13]) survivors of HTx. HTx recipients were compared with 39 individuals with essential hypertension and 25 normotensive controls. RESULTS Hypertensive HTx recipients had raised NO2(-) + NO3(-) levels in plasma, positively correlated with 24-hour mean blood pressure (BP). In contrast, individuals with essential hypertension had decreased NO2(-) + NO3(-) concentration comparing controls, inversely correlated with 24-hour mean BP. Moreover, although TNF-alpha levels were significantly raised in HTx recipients compared with both healthy controls and individuals with essential hypertension, it was positively correlated to 24-hour BP and NO2(-) + NO3(-). Although only a slight increase was found in essential hypertension, no correlations were found in these nontransplant individuals. Finally, although asymmetric dimethylarginine (ADMA) tended to be raised in essential hypertension, this endogenous nitric oxide synthase (NOS) inhibitor was significantly decreased in HTx recipients compared with normotensive controls., Conclusion: Our findings suggest that different mechanisms may be operating in the pathogenesis of posttransplant compared with essential hypertension, with persistent inflammation, raised NO2(-) + NO3(-), and decreased ADMA levels characterizing the former group.

Background: The pathogenesis of atherosclerosis and acute coronary syndromes involves inflammation and immunological mechanisms. We hypothesized that patients with unstable angina may have an imbalance between inflammatory and anti-inflammatory cytokines., Design: Plasma levels of tumour necrosis factor (TNF)alpha and interleukin (IL)-10 were analyzed in 44 patients with stable angina, 29 patients with unstable angina and 20 controls. mRNA levels of these cytokines were analyzed in peripheral blood mononuclear cells (PBMC). We also studied the in vitro effects of IL-10 in PBMC from unstable angina patients., Results: Our main findings were: (1) the angina patients and particularly those with unstable disease had significantly raised TNFalpha in comparison with the controls, both at the protein and mRNA level; (2) in contrast, the levels of IL-10 were not different in the angina patients in comparison with the healthy controls, resulting in a markedly enhanced TNFalpha:IL-10 ratio, particularly in the unstable angina patients; (3) while exogenously added IL-10 markedly inhibited the release of TNFalpha, IL-8 and tissue factor as well as impairing the gelatinolytic activity and mRNA production of matrix metalloproteinase-9, it enhanced the tissue inhibitor of this metalloproteinase (i.e. TIMP-1) in PBMC from the unstable angina patients., Conclusion: Patients with unstable angina appear to have an imbalance between TNFalpha and IL-10, possibly favouring inflammatory net effects. IL-10 may have beneficial effects on mechanisms that are important in plaque rupture and thrombus formation.

Background: Congestive heart failure (CHF) is characterized by enhanced immune activation, which possibly plays a pathogenic role in this disorder. We therefore examined whether immunomodulation with thalidomide could improve cardiac performance in patients with CHF., Methods: Nine patients with chronic symptomatic CHF and left ventricular ejection fraction (LVEF) <40%, who were receiving "optimal" conventional cardiovascular treatment, were given 200 mg thalidomide daily in an open design for a period of 6 weeks. Tumor necrosis factor (TNF)-alpha and LVEF were measured at baseline and on completion of the study., Results: Two patients withdrew because of side effects. Sedation was common and required dose reduction in 6 of 7 patients completing the study. Plasma levels of TNF-alpha were elevated at baseline compared with levels in healthy control patients, but decreased significantly from 33.9 +/- 10.1 pg/mL to 19.3 +/- 6.1 pg/mL during therapy (P <.05). LVEF increased in all patients from 26% +/- 9% to 34% +/- 10% at the end of the observation period (P <.05)., Conclusions: In this pilot study, therapy with thalidomide in patients with CHF resulted in decreased TNF-alpha levels and increased cardiac performance. Although few patients were included, our results suggest that thalidomide should be further investigated as an immunomodulating agent in CHF.