Are Martin Holm

Relevance of biallelic versus monoallelic TNFRSF13B mutations in distinguishing disease-causing from risk-increasing TNFRSF13B variants in antibody deficiency syndromes

TNFRSF13B encodes transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI), a B cell- specific tumor necrosis factor (TNF) receptor superfamily member. Both biallelic and monoallelic TNFRSF13B mutations were identified in patients with common variable immunodeficiency disorders. The genetic complexity and variable clinical presentation of TACI deficiency prompted us to evaluate the genetic, immunologic, and clinical condition in 50 individuals with TNFRSF13B alterations, following screening of 564 unrelated patients with hypogammaglobulinemia. We identified 13 new sequence variants. The most frequent TNFRSF13B variants (C104R and A181E; n=39; 6.9%) were also present in a heterozygous state in 2% of 675 controls. All patients with biallelic mutations had hypogammaglobulinemia and nearly all showed impaired binding to a proliferation-inducing ligand (APRIL). However, the majority (n=41; 82%) of the pa-tients carried monoallelic changes in TNFRSF13B. Presence of a heterozygous mutation was associated with antibody deficiency (P< .001, relative risk 3.6). Heterozygosity for the most common mutation, C104R, was associated with disease (P< .001, relative risk 4.2). Furthermore, heterozygosity for C104R was associated with low numbers of IgD(-)CD27(+) B cells (P= .019), benign lymphoproliferation (P< .001), and autoimmune complications (P= .001). These associations indicate that C104R heterozygosity increases the risk for common variable immunodeficiency disorders and influences clinical presentation.

Enhanced expression of inflammatory cytokines and activation markers in T-cells from patients with chronic heart failure.

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.

Stromal Cell–Derived Factor-1α in Unstable Angina Potential Antiinflammatory and Matrix-Stabilizing Effects

Background—Chemokines play a pathogenic role in atherogenesis and plaque destabilization by activating and directing leukocytes into the atherosclerotic plaque. However, stromal cell–derived factor (SDF)-1 was recently found to have antiinflammatory effects, and we hypothesized that this chemokine could play a beneficial role in coronary artery disease. Methods and Results—Plasma levels of SDF-1&agr; were significantly decreased in patients with stable (n=30) and unstable angina (n=30) compared with healthy control subjects (n=20), particularly in those with unstable disease. By flow cytometry and RNase protection assay, we found decreased surface expression but increased gene expression of the SDF-1&agr; receptor CXCR-4 in peripheral blood mononuclear cells (PBMC) from patients with stable angina and patients with unstable angina. In vitro, SDF-1&agr; (500 ng/mL) reduced both unstimulated and endotoxin/mitogen-stimulated mRNA and protein levels of monocyte chemoattractant protein-1, interleukin-8, matrix metalloproteinase-9, and tissue factor while increasing tissue inhibitor of metalloproteinases-1 in PBMC from patients with unstable angina. The SDF-1&agr;–mediated suppression of monocyte chemoattractant protein-1 and interleukin-8 appears to involve cAMP/protein kinase A type I–dependent pathways. Finally, although SDF-1&agr; suppressed the spontaneous release of these inflammatory mediators in unstable angina, enhancing effects were seen in unstimulated PBMC from healthy control subjects, possibly reflecting that PBMC in unstable angina are preactivated in vivo. Conclusions—In contrast to several other chemokines, our findings suggest that SDF-1&agr;, at least in high concentrations, may mediate antiinflammatory and matrix-stabilizing effects in unstable angina. These effects may promote plaque stabilization, and therapeutic intervention that enhances SDF-1&agr; activity could potentially be beneficial in acute coronary syndromes.

Hydroxymethylglutaryl coenzyme a reductase inhibitors down-regulate chemokines and chemokine receptors in patients with coronary artery disease ☆

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.

Low numbers of regulatory T cells in common variable immunodeficiency: association with chronic inflammation in vivo

Common variable immunodeficiency (CVID) is a heterogeneous syndrome characterized by defective immunoglobulin production and high frequency of bacterial infections, autoimmunity and manifestations of chronic inflammation. Abnormalities of CD4+CD25highforkhead box P3 (FoxP3)+ regulatory T cells (Treg) have been associated with autoimmune and inflammatory disorders, and we hypothesized that CVID might be characterized by Treg abnormalities. CD3+ cells from patients and controls were analysed for the expression of FoxP3 mRNA by real time reverse transcription–polymerase chain reaction (RT–PCR). Peripheral blood mononuclear cells from CVID patients and controls were stained for Treg markers, analysed by flow cytometry and compared to clinical characteristics. The main findings were: (i) CVID patients had significantly decreased expression of FoxP3 mRNA and decreased proportions of CD4+CD25highFoxP3+ cells compared to controls; (ii) CVID patients with splenomegaly had even lower proportions of Treg compared to other patients and controls; (iii) serum levels of the inflammatory marker neopterin were correlated negatively with the proportions of Treg within the CVID population, while there was no significant association with bronchiectasis. We have demonstrated decreased proportions of Treg in CVID patients, particularly in those with signs of chronic inflammation. Decreased proportions of TReg are suggested to be pathogenetically important in autoimmunity, and our results suggest that TReg may have a similar role in CVID.

Impaired Secretion of IL-10 by T Cells from Patients with Common Variable Immunodeficiency–Involvement of Protein Kinase A Type I

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.

Common variable immunodeficiency and the complement system; low mannose-binding lectin levels are associated with bronchiectasis.

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.

Gene expression analysis of peripheral T cells in a subgroup of common variable immunodeficiency shows predominance of CCR7– effector‐memory T cells

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.

Development of pulmonary abnormalities in patients with common variable immunodeficiency: associations with clinical and immunologic factors

BACKGROUND Patients with common variable immunodeficiency (CVID) have low serum IgG, IgA, and/or IgM levels and recurrent airway infections. Radiologic pulmonary abnormalities and impaired function are common complications. It is unclear to what extent IgG replacement treatment prevents further pulmonary damage and how factors beside infections may contribute to progression of disease. OBJECTIVES To study the development of pulmonary damage and determine how clinical and immunologic factors, such as serum IgG, may contribute to possible changes. METHODS In a retrospective, longitudinal study of 54 patients with CVID already treated with immunoglobulins, we examined changes of lung function and findings on high-resolution computed tomography (HRCT), obtained at 2 time points (the date of the last pulmonary function measurement before April 2005 [T1] and the date of the measurement performed closest to 5 years earlier [T0]) 2 to 7 years apart and explored possible relations to clinical and immunologic factors such as levels of IgG, tumor necrosis alpha (TNF-alpha), and mannose-binding lectin (MBL) in serum. RESULTS Despite a mean (SD) serum IgG level of 7.6 (2.3) g/L for all the patients during the entire study period, lung function decreased from T0 to T1. The combination of a low serum IgA level and serum MBL was associated with the presence of bronchiectasis and lower lung function and with worsening of several HRCT abnormalities from T0 to T1. Increased serum levels of TNF-alpha were related to deterioration of gas diffusion. A mean serum IgG level less than 5 g/L between T0 and T1 was associated with worsening of linear and/or irregular opacities seen on HRCT. CONCLUSION For a period of 4 years, lung function and HRCT deteriorated in CVID patients treated with immunoglobulins.

A unique set of 6 circulating microRNAs for early detection of non-small cell lung cancer

Introduction Circulating microRNAs are promising biomarkers for diagnosis, predication and prognostication of diseases. Lung cancer is the cancer disease accountable for most cancer deaths, largely due to being diagnosed at late stages. Therefore, diagnosing lung cancer patients at an early stage is crucial for improving the outcome. The purpose of this study was to identify circulating microRNAs for detection of early stage lung cancer, capable of discriminating lung cancer patients from those with chronic obstructive pulmonary disease (COPD) and healthy volunteers. Results We identified 7 microRNAs separating lung cancer patients from controls. By using RT-qPCR, we validated 6 microRNAs (miR-429, miR-205, miR-200b, miR-203, miR-125b and miR-34b) with a significantly higher abundance in serum from NSCLC patients. Furthermore, the 6 miRNAs were validated in a different dataset, revealing an area under the receiver operating characteristic curve of 0.89 for stage I-IV and 0.88 for stage I/II. Materials and Methods We profiled the expression of 754 unique microRNAs by TaqMan Low Density Arrays, and analyzed serum from 38 patients with NSCLC, 16 patients suffering from COPD and 16 healthy volunteers from Norway, to explore their potential as diagnostic biomarkers. For validation, we analyzed serum collected from high-risk individuals enrolled in the Valencia branch of the International Early Lung Cancer Action Program screening trial (n=107) in addition to 51 lung cancer patients. Conclusion Considering the accessibility and stability of circulating miRNAs, these 6 microRNAs are promising biomarkers as a supplement in future screening studies.