Myositis-related autoantibody profile and clinical characteristics stratified by anti-cytosolic 5'-nucleotidase 1A status in connective tissue diseases

INTRODUCTION/AIMS

Cytosolic 5'-nucleotidase 1A (cN-1A) autoantibodies have been recognized as myositis-related autoantibodies. However, their correlations with clinical characteristics and other myositis-specific and myositis-associated autoantibodies (MSAs/MAAs) are still unclear. We aimed to establish the prevalence and clinical and laboratory associations of cN-1A autoantibodies in a cohort of patients with connective tissue diseases.

METHODS

A total of 567 participants (182 idiopathic inflammatory myopathies [IIM], 164 systemic lupus erythematosus [SLE], 121 systemic sclerosis [SSc], and 100 blood donors [BD]) were tested for the presence of cN-1A autoantibodies and other myositis-specific and myositis-associated autoantibodies (MSAs/MAAs). Clinical and laboratory characteristics were compared between anti-cN-1A positive and negative patients with sporadic inclusion body myositis (sIBM) and between anti-cN-1A positive and negative patients with non-IBM IIM.

RESULTS

In the sIBM cohort, 30 patients (46.9%) were anti-cN-1A positive vs. 18 (15.2%) in the non-IBM IIM cohort, 17 (10%) were anti-cN-1A positive in the SLE cohort and none in the SSc or the BD cohorts. Anti-cN-1A positivity had an overall sensitivity of 46.9% and a specificity of 93.2% for sIBM. Dysphagia was more frequent in the anti-cN-1A positive vs. negative sIBM patients (p = .04). In the non-IBM IIM group, being anti-cN-1A antibody positive was associated with the diagnosis polymyositis (p = .04) and overlap-myositis (p = .04) and less disease damage evaluated by physician global damage score (p < .001).

DISCUSSION

cN-1A autoantibodies were predominantly found in IIM patients and was associated with dysphagia in sIBM patients. Notably, anti-cN-1A appears to identify a distinct phenotype of anti-cN-1A positive non-IBM IIM patients with a milder disease course.

Peptide Antibody Reactivity to Homologous Regions in Glutamate Decarboxylase Isoforms and Coxsackievirus B4 P2C

Two isoforms of the glutamate decarboxylase (GAD) enzyme exist, GAD65 and GAD67, which are associated with type 1 diabetes (T1D) and stiff-person syndrome (SPS), respectively. Interestingly, it has been reported that T1D patients seldom develop SPS, whereas patients with SPS occasionally develop T1D. In addition, coxsackievirus B4 (CVB4) has previously been proposed to be involved in the onset of T1D through molecular mimicry. On this basis, we aimed to examine antibody cross-reactivity between a specific region of GAD65 and GAD67, which has high sequence homology to the nonstructural P2C protein of CVB4 to determine potential correlations at antibody level. Monoclonal peptide antibodies generated in mice specific for a region with high similarity in all three proteins were screened for reactivity along with human sera in immunoassays. In total, six antibodies were generated. Two of the antibodies reacted to both GAD isoforms. However, none of the antibodies were cross-reactive to CVB, suggesting that antibody cross-reactivity between GAD65 and CVB, and GAD67 and CVB may not contribute to the onset of T1D and SPS, respectively.

Myositis-Specific Autoantibodies and QTc Changes by ECG in Idiopathic Inflammatory Myopathies

OBJECTIVES

The aim of this study was to investigate cardiac involvement detected by electrocardiography (ECG) in patients with idiopathic inflammatory myopathies (IIM) and to evaluate possible associations between autoantibody profile and ECG changes in these patients.

METHODS

In a Scandinavian cross-sectional study, patients were included from two Danish centres and one Swedish centre. Resting 12-lead ECG was investigated in 261 patients with IIM compared with 102 patients with systemic sclerosis (SSc) and 48 healthy controls (HCs). ECG changes were correlated to clinical manifestations and myositis-specific (MSAs) and myositis-associated (MAAs) autoantibodies.

RESULTS

Patients with IIM had longer mean QTc duration and more frequently presented with prolonged QTc (≥ 450 ms; p= 0.038) compared with HCs. Longer QTc duration was recorded in SSc compared with IIM (433 ± 23 ms vs 426 ± 24 ms, p= 0.011), yet, no significant difference in the fraction with prolonged QTc (SSc: 22%, IIM: 16%; p= 0.19). In multivariable regression analyses, anti-Mi2 (p= 0.01, p= 0.035) and anti-Pl-7 (p= 0.045, p= 0.014) were associated with QTc duration and prolonged QTc in IIM. Elevated CRP was associated with prolonged QTc (p= 0.041).

CONCLUSION

Presence of QTc abnormalities was as common in patients with IIM as in patients with SSc, including prolonged QTc seen in almost one fifth of the patients. Anti-Mi2, anti-Pl-7, and elevated CRP may serve as biomarkers for cardiac disease in IIM, but needs to be confirmed in a larger prospective study.

Determination of Autoantibodies by Line Immunoblotting

Autoantibody detection is a useful and obligatory tool for clinicians and researchers in diagnosing autoimmune diseases. Line blotting is a simple, sensitive, and flexible technique for fast semiquantitative detection of multiple antibodies. Line blotting enables the detection of antibodies on membrane strips coated with thin parallel lines of several purified, biochemically characterized antigens, which are fixed onto a synthetic support. Each strip can contain more than ten antigens, thus allowing simultaneous screening for multiple antibodies. Here, we describe the principle of line blotting and how the buffer composition can interfere with the results of autoantibody detection.

Comparison of antibody assays for detection of autoantibodies to Ro 52, Ro 60 and La associated with primary Sjögren's syndrome

Anti-Ro(52/60) and anti-La constitute the hallmark autoantibodies in primary Sjögren's syndrome, being present in 40-70% of sera. Several anti-Ro/La assays exist, but antibody detection appears to be assay-specific, thus the aim of this study was to compare several anti-Ro/La assays. In total, 96 sera from individuals with primary Sjögren's syndrome and 114 healthy controls were tested for anti-Ro 52/60 and anti-La in 17 immunoassays. Especially the immunoassays used for detection of anti-Ro 52 differed in their sensitivity (48-79%), while only small differences in sensitivities were observed for the anti-Ro 60 (69-77%) anti-La (39-44%) assays. Concordances of 65%, 79% and 73% for the anti-Ro 52, anti-Ro 60 and anti-La assays were found, respectively. The majority of the assays yielded high specificities, primarily ranging from 97 to 100%, except from a single anti-Ro 60 assay, which yielded a specificity of 79%. Occasionally, reactivity levels were increased in a few assays, indicating that false-positive results can be obtained when applying assays of reduced specificity. In general, the commercial assays appeared to perform better than the in-house analyses. When correcting the in-house assays for background reactivity, sensitivities were reduced by approximately 7%, 17%, and 19% for anti-Ro 52, anti-Ro 60 and anti-La assays, respectively, illustrating the pitfalls when applying immunoassays for detection of autoantibodies, which in theory may apply to commercial assays as well. Finally, increased total sensitivities were obtained when combining assays. These studies contribute to clarify the clinical utility of immunoassays for detection of autoantibodies of Ro 52, Ro 60 and La and illustrate that the most efficient strategy to maximize antibody sensitivity is to combine several assays.

Characterization of continuous monoclonal antibody epitopes in the N-terminus of Ro60

One of the major targets of the autoimmune response in the rheumatic autoimmune diseases, Systemic Lupus Erythematosus and Sjögrens Syndrome, is the protein Ro60. Ro60 is known to associate with small misfolded RNAs, and is involved in RNA quality control and in enhancing cell survival during cellular stress, e.g. after ultaviolet irradiation. In this study, six monoclonal antibodies to Ro60 were analyzed in order to identify antigenic regions and the nature of these. Preliminary analyses revealed that two of the antibodies recognized continuous epitopes, while the remaining antibodies most likely recognized conformational epitopes. The continuous epitopes of Ro60 were characterised by modified immunoassays employing resin-bound peptides and free peptides. Peptide screenings located the epitopes to the N-terminus of Ro60, and further analyses indicated that the epitopes of the monoclonal antibodies TROVE2 and SSI-HYB 358-02 were located to amino acids 8-17 and 34-49, respectively. Moreover, charged amino acids were found to be especially important for antibody reactivity, although antibody reactivity of the monoclonal antibody TROVE2 primarily was found to be epitope backbone-dependent.

Immunocytochemical and Immunohistochemical Staining with Peptide Antibodies

Peptide antibodies are particularly useful for immunocytochemistry (ICC) and immunohistochemistry (IHC), where antigens may denature due to fixation of tissues and cells. Peptide antibodies can be made to any defined sequence, including unknown putative proteins and posttranslationally modified sequences. Moreover, the availability of large amounts of the antigen (peptide) allows inhibition/adsorption controls, which are important in ICC/IHC, due to the many possibilities for false-positive reactions caused by immunoglobulin Fc receptors, nonspecific reactions, and cross-reactivity of primary and secondary antibodies with other antigens and endogenous immunoglobulins, respectively. Here, simple protocols for ICC and IHC are described together with recommendations for appropriate controls.

Production and Screening of Monoclonal Peptide Antibodies

Hybridoma technology is a remarkable and indispensable tool for generating high-quality monoclonal antibodies. Hybridoma-derived monoclonal antibodies not only serve as powerful research and diagnostic reagents, but have also emerged as the most rapidly expanding class of therapeutic biologicals. In this chapter, an overview of hybridoma technology and the laboratory procedures used routinely for hybridoma production and antibody screening are presented, including characterization of peptide antibodies.

An azumamide C analogue without the zinc-binding functionality

Histone deacetylase (HDAC) inhibitors have attracted considerable attention due to their promise as therapeutic agents.

Influence of levamisole and other angiogenesis inhibitors on angiogenesis and endothelial cell morphology in vitro

Angiogenesis, the formation of new blood vessels from existing vessels is required for many physiological processes and for growth of solid tumors. Initiated by hypoxia, angiogenesis involves binding of angiogenic factors to endothelial cell (EC) receptors and activation of cellular signaling, differentiation, migration, proliferation, interconnection and canalization of ECs, remodeling of the extracellular matrix and stabilization of newly formed vessels. Experimentally, these processes can be studied by several in vitro and in vivo assays focusing on different steps in the process. In vitro, ECs form networks of capillary-like tubes when propagated for three days in coculture with fibroblasts. The tube formation is dependent on vascular endothelial growth factor (VEGF) and omission of VEGF from the culture medium results in the formation of clusters of undifferentiated ECs. Addition of angiogenesis inhibitors to the coculture system disrupts endothelial network formation and influences EC morphology in two distinct ways. Treatment with antibodies to VEGF, soluble VEGF receptor, the VEGF receptor tyrosine kinase inhibitor SU5614, protein tyrosine phosphatase inhibitor (PTPI) IV or levamisole results in the formation of EC clusters of variable size. This cluster morphology is a result of inhibited EC differentiation and levamisole can be inferred to influence and block VEGF signaling. Treatment with platelet factor 4, thrombospondin, rapamycin, suramin, TNP-470, salubrinal, PTPI I, PTPI II, clodronate, NSC87877 or non-steriodal anti-inflammatory drugs (NSAIDs) results in the formation of short cords of ECs, which suggests that these inhibitors have an influence on later steps in the angiogenic process, such as EC proliferation and migration. A humanized antibody to VEGF is one of a few angiogenesis inhibitors used clinically for treatment of cancer. Levamisole is approved for clinical treatment of cancer and is interesting with respect to anti-angiogenic activity in vivo since it inhibits ECs in vitro with a morphology resembling that obtained with antibodies to VEGF.

Synthesis and antiangiogenic activity of N-alkylated levamisole derivatives

Inhibition of angiogenesis is a promising addition to current cancer treatment strategies. Neutralization of vascular endothelial growth factor by monoclonal antibodies is clinically effective but may cause side effects due to thrombosis. Low molecular weight angiogenesis inhibitors are currently less effective than antibody treatment and are also associated with serious side effects. The discovery of new chemotypes with efficient antiangiogenic activity is therefore of pertinent interest. (S)-levamisole hydrochloride, an anthelminthic drug approved for human use and with a known clinical profile, was recently shown to be an inhibitor of angiogenesis in vitro and exhibited tumor growth inhibition in mice. Here we describe the synthesis and in vitro evaluation of a series of N-alkylated analogues of levamisole with the aim of characterizing structure-activity relationships with regard to inhibition of angiogenesis. N-methyllevamisole and p-bromolevamisole proved more effective than the parent compound, (S)-levamisole hydrochloride, with respect to inhibition of angiogenesis and induction of undifferentiated cluster morphology in human umbilical vein endothelial cells grown in co-culture with normal human dermal fibroblasts. Interestingly, the cluster morphology caused by N-methyllevamisole was different than the clusters observed for levamisole, and a third "cord-like" morphology resembling that of the known drug suramin was observed for an aniline-containing derivative. New chemotypes exhibiting antiangiogenic effects in vitro are thus described, and further investigation of their underlying mechanism of action is warranted.

Direct intramyocardial mesenchymal stromal cell injections in patients with severe refractory angina: one-year follow-up

In patients with stable coronary artery disease (CAD) and refractory angina, we performed direct intramyocardial injections of autologous mesenchymal stromal cells (MSC) and followed the safety and efficacy of the treatment for 12 months. A total of 31 patients with stable CAD, moderate to severe angina, normal left ventricular ejection fraction, and no further revascularization options were included. Bone marrow MSCs were isolated and culture expanded for 6-8 weeks and then stimulated with vascular endothelial growth factor (VEGF) for 1 week. The 12-month follow-up demonstrated that it was safe to culture expand MSCs and use the cells for clinical treatment. The patients' maximal metabolic equivalent (MET) during exercise increased from 4.23 MET at baseline to 4.72 MET at 12-month follow-up (p < 0.001), Canadian Cardiovascular Society Class (CCS) was reduced from 3.0 to 0.8 (p < 0.001), angina attacks per week from 13.8 to 3.2 (p < 0.001), and nitroglycerin consumption from 10.7 to 3.4 per week (p < 0.001). In addition, Seattle Angina Questionnaire (SAQ) evaluations demonstrated highly significant improvements in physical limitation, angina stability, angina frequency, and quality of life (p < 0.001 for all). It is safe in the intermediate/long term to treat patients with stable CAD using autologous culture expanded MSCs. Previously reported, early and highly significant improvements in exercise capacity and clinical symptoms persist after 12 months. The results are encouraging, and a larger controlled study is warranted.

Mesenchymal stromal cell derived endothelial progenitor treatment in patients with refractory angina

AIMS

We evaluated the feasibility, safety and efficacy of intra-myocardial injection of autologous mesenchymal stromal cells derived endothelial progenitor cell (MSC) in patients with stable coronary artery disease (CAD) and refractory angina in this first in man trial.

METHODS AND RESULTS

A total of 31 patients with stable CAD, moderate to severe angina and no further revascularization options, were included. Bone marrow MSC were isolated and culture expanded for 6-8 weeks. It was feasible and safe to establish in-hospital culture expansion of autologous MSC and perform intra-myocardial injection of MSC. After six months follow-up myocardial perfusion was unaltered, but the patients increased exercise capacity (p < 0.001), reduction in CCS Class (p < 0.001), angina attacks (p < 0.001) and nitroglycerin consumption (p < 0.001), and improved Seattle Angina Questionnaire (SAQ) evaluations (p < 0.001). For all parameters there was a tendency towards improved outcome with increasing numbers of cells injected. In the MRI substudy: ejection fraction (p < 0.001), systolic wall thickness (p = 0.03) and wall thickening (p = 0.03) all improved.

CONCLUSIONS

The study demonstrated that it was safe to treat patients with stable CAD with autologous culture expanded MSC. Moreover, MSC treated patients had significant improvement in left ventricular function and exercise capacity, in addition to an improvement in clinical symptoms and SAQ evaluations.

Mesenchymal stromal cell and mononuclear cell therapy in heart disease

Despite progress in percutaneous coronary intervention, bypass surgery and drug therapy, rates of mortality and morbidity after acute coronary syndrome are high due to ventricular remodeling and heart failure. Mesenchymal stromal cells (MSCs) from adult bone marrow or adipose tissue are considered potential candidates for therapeutic regenerative treatment in cardiovascular disease. Recent animal studies have demonstrated that MSCs can induce neovascularization and improve myocardial function in postinfarction myocardial ischemic hearts. This review will focus on the present preclinical and clinical knowledge about the use of mononuclear cells and MSCs for cardiac regenerative medicine, the source of MSCs for clinical use and problems to consider when conducting clinical MSC therapy.

Synthesis and anti-angiogenic effect of conjugates between serum albumin and non-steroidal anti-inflammatory drugs

Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit tumor growth and angiogenesis. Covalent linkage of naproxen to human serum albumin (HSA) has been shown to target it efficiently to the liver and this may potentially be exploited for liver-selective inhibition of angiogenesis. With the aim of investigating the anti-angiogenic efficiency of NSAID-HSA conjugates in vitro, three NSAIDs, aspirin, ibuprofen, and naproxen were conjugated to HSA using different concentrations of their N-hydroxysuccinimide esters. Conjugation ratios from 10 to 50 were achieved and the conjugates retained a growth inhibitory effect on endothelial cells at or above the level of the non-conjugated NSAIDs in an in vitro angiogenesis assay.

The influence of propranolol on the extrathyroidal metabolism of 3,3',5'-triiodothyronine (reverse T3)

The effect of propranolol 80 mg daily on the metabolism of 3,3',5'-triiodothyronine (reverse T3, rT3), 3,3',5'-triiodothyronine (T3) and thyroxine (T4) was studied by means of a non compartmental kinetic method in seven females with severe pretreatment hypothyroidism. The patients were maintained euthyroid on a constant L-T4 replacement therapy. Serum rT3 levels increased significantly during propranolol (p less than 0.02). This increase was explained by a decrease in metabolic clearance rate (MCR) (p less than 0.02), since the conversion rate from T4 and the distribution volume of rT3 were unchanged. By contrast the decreased serum levels of T3 were due to a significant decreased conversion from T4 (p less than 0.02) in spite of a decreased MCR. The results are compatible with the assumption of two different monodeiodinating enzymes, a 5-deiodinase responsible for the diodination of T4 to rT3 and a 5'-deiodinase responsible for the deiodination of T4 to T3.

The clinical value of serum triiodothyronine, thyroxine and thyrotropin estimations during medical antithyroid treatment

The relation between clinical status and serial determinations of serum T3, serum T4 and serum TSH has been evaluated in the early phase of medical antithyroid treatment in 12 unselected hyperthyroid patients, and in 19 patients who later during treatment accidentally developed low serum T4 values. Determination of both serum T3 and serum T4 was found necessary to avoid undertreatment. Two patients with signs of hypothyroidism in the early phase developed low serum T4, while serum T3 and serum TSH remained normal. In all of the 19 patients selected with low serum T4, serum T3 was normal. Serum TSH was elevated in 5 patients without hypothroid symptoms, while 2 developed hypothyroid symptoms in spite of normal serum TSH values. Our results suggest that serum T4 is a more sensitive parameter than both serum TSH and serum T3 in avoiding overtreatment during medical antithyroid treatment.

YKL-40 a new biomarker in patients with acute coronary syndrome or stable coronary artery disease

BACKGROUND

YKL-40 is involved in remodelling and angiogenesis in non-cardiac inflammatory diseases. Aim was to quantitate plasma YKL-40 in patients with ST-elevation myocardial infarction (STEMI) or stable chronic coronary artery disease (CAD), and YKL-40 gene activation in human myocardium.

METHODS AND RESULTS

We included 73 patients: I) 20 patients with STEMI; II) 28 patients with stable CAD; III) 15 CAD patients referred for coronary by-pass surgery. YKL-40 mRNA expression was measured in myocardium subtended by stenotic or occluded arteries and areas with no apparent disease; and IV) 10 age-matched healthy controls. Plasma YKL-40 was significantly increased in patients with STEMI (88 microg/l, median) and CAD (66 microg/l) compared to controls (16 microg/l, p<0.01 for both). Plasma YKL-40 correlated with CRP at baseline in STEMI (r=0.53, p=0.02) and CAD patients (r=0.41, p=0.031).YKL-40 gene expression was similar in ischemic and non-ischemic myocardium.

CONCLUSIONS

Plasma YKL-40 was significantly increased in patients with STEMI and stable CAD. Further studies will define the role of YKL-40 as a clinically useful marker for myocardial ischemia, remodelling and maybe prognosis.

Comparison of different culture conditions for human mesenchymal stromal cells for clinical stem cell therapy

OBJECTIVE

Mesenchymal stromal cells (MSCs) from adult bone marrow (BM) are considered potential candidates for therapeutic neovascularization in cardiovascular disease. When implementing results from animal trials in clinical treatment, it is essential to isolate and expand the MSCs under conditions following good manufacturing practice (GMP). The aims of the study were first to establish culture conditions following GMP quality demands for human MSC expansion and differentiation for use in clinical trials, and second to compare these MSCs with MSCs derived from culture in four media commonly used for MSC cultivation in animal studies simulating clinical stem cell therapy.

MATERIAL AND METHODS

Human mononuclear cells (MNCs) were isolated from BM aspirates by density gradient centrifugation and cultivated in a GMP-accepted medium (EMEA medium) or in one of four other media.

RESULTS

FACS analysis showed that the plastic-adherent MSCs cultured in EMEA medium or in the other four media were identically negative for the haematopoietic surface markers CD45 and CD34 and positive for CD105, CD73, CD90, CD166 and CD13, which in combined expression is characteristic of MSCs. MSC stimulation with vascular endothelial growth factor (VEGF) increased expression of the characteristic endothelial genes KDR and von Willebrand factor; the von Willebrand factor and CD31 at protein level as well as the capacity to develop capillary-like structures.

CONCLUSIONS

We established culture conditions with a GMP compliant medium for MSC cultivation, expansion and differentiation. The expanded and differentiated MSCs can be used in autologous mesenchymal stromal cell therapy in patients with ischaemic heart disease.

Bone marrow derived mesenchymal cell mobilization by granulocyte-colony stimulating factor after acute myocardial infarction: results from the Stem Cells in Myocardial Infarction (STEMMI) trial

BACKGROUND

Granulocyte-colony stimulating factor (G-CSF) after myocardial infarction does not affect systolic function when compared with placebo. In contrast, intracoronary infusion of bone marrow cells appears to improve ejection fraction. We aimed to evaluate the G-CSF mobilization of subsets of stem cells.

METHODS AND RESULTS

We included 78 patients (62 men; 56+/-8 years) with ST-elevation myocardial infarction treated with primary percutaneous intervention <12 hours after symptom onset. Patients were randomized to double-blind G-CSF (10 microg/kg/d) or placebo. Over 7 days, the myocardium was exposed to 25x10(9) G-CSF mobilized CD34+ cells, compared with 3x10(9) cells in placebo patients (P<0.001); and to 4.9x10(11) mesenchymal stem cells, compared with 2.0x10(11) in the placebo group (P<0.001). The fraction of CD34+ cells/leukocyte increased during G-CSF treatment (from 0.3+/-0.2 to 1.1+/-0.9 x10(-3), P<0.001 when compared with placebo), whereas the fraction of putative mesenchymal stem cells/leukocyte decreased (from 22+/-17 to 14+/-11 x10(-3), P=0.01 when compared with placebo). An inverse association between number of circulating mesenchymal stem cells and change in ejection fraction was found (regression coefficient -6.8, P=0.004), however none of the mesenchymal cell subtypes analyzed, were independent predictors of systolic recovery.

CONCLUSIONS

The dissociated pattern for circulating CD34+ and mesenchymal stem cells could be attributable to reduced mesenchymal stem cell mobilization from the bone marrow by G-CSF, or increased homing of mesenchymal stem cells to the infarcted myocardium. The inverse association between circulating mesenchymal stem cells and systolic recovery may be of clinical importance and should be explored further.

The influence of freezing and storage on the characteristics and functions of human mesenchymal stromal cells isolated for clinical use

BACKGROUND

Studies have shown that stem cell therapy could be a novel option for improving neovascularization and cardiac function in patients with ischemic heart disease. Human mesenchymal stromal cells (MSC) have generated wide interest in the clinical setting because of their ability to regenerate tissue. The aim of the study was to test whether freezing and storage of human BM mononuclear cells (BM-MNC) and ex vivo-expanded MSC influenced their phenotypic and functional characteristics as well as proliferation capacity.

METHODS

MNC were isolated from BM and divided into two portions: one part was immediately cultured (MSC P0) whereas the second part was frozen for a week before cultivation and analysis (F-MSC P1). Confluent MSC (P0) were harvested and divided: one was analyzed as MSC P1 and the other was frozen for a week before further cultivation and analysis as F-MSC P2.

RESULTS

MSC P1, F-MSC P1 and F-MSC P2 had similar proliferation capacities and demonstrated almost identical expression levels of markers characteristic for MSC. The capacity to form endothelial vascular structures was independent of freezing.

DISCUSSION

The proliferation and differentiation capacity as well as the cellular characteristics were identical in cultivated MSC derived from freshly isolated BM-MNC and MSC derived after freezing and storage of either freshly isolated BM-MNC or ex vivo-cultivated MSC. This highlights the potential clinical use of MSC in patients with cardiac and degenerative diseases, as it would be possible to inject MSC obtained from the same BM aspiration at different time points.

Influence of angiogenesis inhibitors on endothelial cell morphology in vitro

Human umbilical vein endothelial cells (HUVEC) propagated in co-culture with fibroblasts form capillary-like networks of tubes. Here we characterize the morphology and ultrastructure of HUVEC in such co-cultures and investigate the influence of different angiogenesis inhibitors on endothelial cell morphology. Addition of angiogenesis inhibitors to the co-culture disrupted endothelial network formation and influenced endothelial cell morphology in two distinct ways. Instead of characteristic capillary-like networks, the endothelial cell morphology appeared as either short cords or compact cell clusters of variable size. Electron microscopy (EM) showed that in co-culture untreated HUVEC formed capillary-like tubes with lumina and retained important ultrastructural and physiological properties of endothelial cells in functional vessels as they contained both Weibel-Palade bodies and transport vesicles. Immuno-EM showed that the endothelial cell marker CD 31 stained endothelial membranes at cell-cell contacts, and at the luminal and abluminal side of the capillary-like tubes, although most abundantly at the luminal membranes. No ultrastructural signs of apoptosis were seen in HUVEC in inhibitor-treated co-cultures. Our results demonstrate that treatment with levamisole or anti-VEGF inhibits endothelial cell differentiation into tubes or instead induces formation of compact endothelial cell clusters. Treatment with platelet factor 4, suramin and TNP-470 results in formation of short endothelial cell cords. We discuss the implications of these findings.

Substrate specificity of the bovine serum amine oxidase and in situ characterisation of aminoaldehydes by NMR spectroscopy

The oxidation of spermidine or homospermidine with bovine serum amine oxidase (BSAO) was monitored in situ, using proton nuclear magnetic resonance spectroscopy in water with 10% D(2)O. NMR assignments were performed by spin decoupling and COSY spectra or by comparison with data from synthetic aminoaldehydes. The results represent the first in situ characterisation of the highly reactive aminoaldehydes and showed oxidation at the N(1) amino group of spermidine and homospermidine. Comparison of homospermidine with a variety of substrates revealed that among straight chain di- and polyamines both an aminopropyl group and two primary amino groups separated by seven (norspermidine) or eight (spermidine) carbon atoms were required for optimal substrate ability. However, highest activity was seen with the substrate N-(4-aminobutyl)hexahydropyrimidine, showing that the substrate channel of BSAO has a dual substrate preference, with moderately bulky substituents at the distal end of a diamine contributing equally well as an alkyl amino group. Cytotoxic investigations of a variety of substrates for BSAO, confirmed previous results, that cytotoxicity is primarily linked to polyamines encompassing the aminopropyl moiety. No acrolein was observed at any time during the oxidation showing that it reacts very fast with available amino groups forming a variety of derivatives.

Levamisole Inhibits Angiogenesis in vitro and Tumor Growth in vivo

The synthetic anthelmintic compound Levamisole has previously been used in cancer treatment as an adjuvant in combination with 5-fluorouracil. Its mode of action remains unclear, but an immune-stimulatory effect has been suggested. Here, we show that Levamisole inhibits angiogenesis in vitro and tumor growth in vivo. In vitro, Levamisole specifically inhibits proliferation and differentiation of endothelial cells propagated in co-culture with fibroblasts. In vivo, Levamisole inhibits the growth in nude mice of a transplanted human tumor. The use of nude mice as tumor hosts permits the discrimination between the angiogenesis inhibitory effect of Levamisole and its assumed immune-stimulatory effect. Our findings support a possible therapeutic effect of angiogenesis inhibitors in the treatment of cancer and call for further investigations of the mechanism(s) underlying the anti-angiogenic effect of Levamisole.

A quantitative ELISA-based co-culture angiogenesis and cell proliferation assay

Since solid tumours and metastases depend on adequate blood supply, much research is focused on inhibition of angiogenesis. Unfortunately, most known angiogenesis inhibitors have serious side effects when used as therapeutic agents in man. It is therefore important to develop methods to identify well-tolerated and efficient angiogenesis inhibitors. As a method for identification of new angiogenesis inhibitors we have further developed the procedure described by Bishop et al. (Angiogenesis 1999;3:335-44) to a quantitative ELISA-based fibroblast and endothelial cell co-culture angiogenesis assay. In each well of a 96-microwell plate, human umbilical vein endothelial cells (HUVEC) are seeded onto normal human dermal fibroblasts (NHDF) and propagated in co-culture for 72 h with or without a potential angiogenesis inhibitor. The effect on total cell proliferation is evaluated by quantitative immunochemical measurement of DNA, and on endothelial tube formation by quantification of CD 31, von Willebrand factor, and collagen IV. After ELISA reading, the morphology of the tubular structures formed by HUVEC is visualised with BCIP/NBT, permitting a quantitative result and a qualitative evaluation of cell morphology from the same well. We have used the assay to demonstrate the effect of well-known angiogenesis inhibitors on HUVEC tube formation.

Microalbuminuria in type 2 diabetic patients: a prospective follow-up study

We have studied 46 patients, 30 men and 16 women, with type 2 (non-insulin-dependent) diabetes in a follow-up period of 6-52 months (mean 30 months). The patients were consecutively entered in the study from the out-patient diabetic clinic. None had urinary tract infections nor proteinuria at entry. Investigations were done every 3 months during the first year and after that every 6 months. At entry 16 patients (35%) had microalbuminuria and a further 16 patients developed microalbuminuria and 16 proteinuria. The systolic blood pressure was higher in men with microalbuminuria compared to men without microalbuminuria. The glomerular filtration rate decreased with time for patients with microalbuminuria without change in plasma creatinine. The C-peptide concentration was higher in the hypertensive patients compared to non-hypertensive and the same was found for the triglyceride concentration. During the observation period the various complications increased in frequency (retinopathy, cardiomyopathy, neuropathy, angiopathy and hypertension) without significant relation to the presence of microalbuminuria or proteinuria. During the observation period nine patients died mainly due to cardiovascular events.

Epigenetic inheritance of transcriptional silencing and switching competence in fission yeast

Epigenetic events allow the inheritance of phenotypic changes that are not caused by an alteration in DNA sequence. Here we characterize an epigenetic phenomenon occurring in the mating-type region of fission yeast. Cells of fission yeast switch between the P and M mating-type by interconverting their expressed mating-type cassette between two allelic forms, mat1-P and mat1-M. The switch results from gene conversions of mat1 by two silent cassettes, mat2-P and mat3-M, which are linked to each other and to mat1. GREWAL and KLAR observed that the ability to both switch mat1 and repress transcription near mat2-P and mat3-M was maintained epigenetically in a strain with an 8-kb deletion between mat2 and mat3. Using a strain very similar to theirs, we determined that interconversions between the switching- and silencing-proficient state and the switching and silencing-deficient state occurred less frequently than once per 1000 cell divisions. Although transcriptional silencing was alleviated by the 8-kb deletion, it was not abolished. We performed a mutant search and obtained a class of trans-acting mutations that displayed a strong cumulative effect with the 8-kb deletion. These mutations allow to assess the extent to which silencing is affected by the deletion and provide new insights on the redundancy of the silencing mechanism.

The Schizosaccharomyces pombe map1 gene encodes an SRF/MCM1-related protein required for P-cell specific gene expression

Cells of Schizosaccharomyces pombe undergo mating and meiosis when starved for a nitrogen source. In this process a P and and M cell first mate to generate a diploid zygote, which subsequently enters meiosis and sporulates. The P mating type is controlled by the mat1-Pc gene at the mating type locus, together with a gene called map1. We show that these two functions are required for expression of the P-specific gene map3. We have cloned the map1 gene and show that it encodes a putative MADS-box containing transcription factor related to mammalian Serum Response Factor (SRF) and Saccharomyces cerevisiae MCM1. The Mat1-Pc protein contains a motif characteristic for proteins that interact with MADS-box factors, suggesting that Mat-Pc and Map1 may form a heterodimer that activates the P-specific map3 gene.

Microalbuminuria in type 2 diabetic patients: a cross-sectional study of frequency, sex distribution and relation to hypertension

We studied 112 type 2 diabetic patients. Fourteen patients had frank proteinuria, and 37 of the remaining 98 had microalbuminuria which was more frequent in men than in women (P < 0.02). Hypertension was found in 47 of the patients, equally distributed between sexes. Male diabetics with microalbuminuria had higher systolic blood pressure than diabetics without microalbuminuria (P < 0.02). Body mass index was higher in both sexes with hypertension compared to patients without hypertension. In the hypertensive men plasma C-peptide values were higher compared to patients without hypertension (P < 0.01) irrespective of the presence of microalbuminuria. A positive correlation between blood pressure and C-peptide was found (P < 0.01) in the men. We suggest that gender should be taken into account in the analysis and interpretation of microalbuminuria in type 2 diabetes.

Nuclear 3,5,3'-triiodothyronine receptor binding in mononuclear blood cells from patients with malignant blood diseases and small cell carcinoma of the lung

We have previously demonstrated enhanced daily turnover of thyroid hormones in patients with hypermetabolic symptoms due to malignant haematologic disorders or small cell carcinoma of the lung. We hypothesized that some of these symptoms might be due to enhanced peripheral effects of T3. We therefore studied the nuclear T3 receptor binding in circulating mononuclear blood cells in 5 patients with malignant haematologic disorders, 5 with untreated small cell carcinoma of the lung, and 11 healthy controls. Maximal binding capacity of T3 (MBC) was increased 2.5 times in the diseased patients, (median (range)) 110 fmol/mg DNA (75-519) in the haematologic group (p < 0.01), 106 fmol/mg DNA (47-490) (p < 0.10) in small cell carcinoma patients, as compared to 43 fmol/mg DNA (26-94) in controls. The affinity constant Ka of bound T3 was reduced to one-third in the diseased patients. No differences were found between serum thyroid hormone or TSH levels. It is hypothesized, that previously demonstrated enhanced turnover of thyroid hormones in these states of disease might in part be due to increased peripheral consumption of thyroid hormones, including enhanced receptor binding of T3.

Hypocalcemia and parathyroid hormone responsiveness in diabetes mellitus: a tri-sodium-citrate clamp study

The aim of this study was to elucidate the diabetic hypocalcemia and PTH responsiveness, investigated by measuring blood ionized calcium and serum intact parathyroid hormone (S-PTH(1-84)) concentrations, before and during an induced and maintained controlled hypocalcemia. In 15 patients with insulin-dependent diabetes mellitus and 19 healthy volunteers the blood ionized calcium concentration was lowered by about 0.20 mmol/l and maintained at this level by blood ionized calcium controlled tri-sodium-citrate infusion. In patients vs controls, baseline measurements averaged for blood ionized calcium (mmol/l) 1.18 +/- 0.08 vs 1.24 +/- 0.03 (p less than 0.01), for S-magnesium (mmol/l) 0.73 +/- 0.07 vs 0.81 +/- 0.07 (p less than 0.01) and for S-PTH (1-84) (pmol/l) 3.0 +/- 1.0 vs 3.1 +/- 1.0 (p greater than 0.75). During the clamp, S-PTH (1-84) peaked to comparable maximums after 5-10 min in both groups and then declined to constant concentrations two to three times above their control levels. In conclusion, we found a diabetic hypocalcemia and hypomagnesemia, though baseline levels of PTH and PTH responsiveness were normal. This may be taken to indicate a mild shift downwards in the set-point for PTH secretion in patients with insulin-dependent diabetes mellitus.

Concentrations of thyroxine, 3,5,3'-triiodothyronine, 3,3',5'-triiodothyronine, 3,3'-diiodothyronine, and 3',5'-diiodothyronine in human red blood cells

A simple and rapid method for the estimation of cellular concentration of thyroxine (T4), 3,5,3'-triiodothyronine (T3), 3,3',5'-triiodothyronine (rT3), 3,3'-diiodothyronine (3,3'-T2), and 3',5'-diiodothyronine (3',5'-T2) as well as their distribution between cytosol and membranes in human red blood cells (RBC) is presented. Concentrations of iodothyronines in RBC (RBC-T) were calculated by multiplying the total serum concentrations by the ratio of radioactivity in equal volumes of packed RBCs and serum, pre-incubated with 125I-labelled iodothyronines of high specific activity. Plasma and RBC were separated by centrifugation in capillary glass tubes. The separation of membranes and cystosol was performed by hypotone lysis and centrifugation. The median RBC-T of T4, T3, rT3, 3,3'-T2, and 3',5'-T2 from 17 euthyroid subjects were 360 pmol/l, 156 pmol/l, 2.77 pmol/l, 6.81 pmol/l, and 2.17 pmol/l, respectively. The cytosol/cytosol + membrane ration were 66%, 40%, 84%, 77%, and 97%, respectively. The differences in RBC-T were not similar to the differences in free serum concentrations. The ratio of RBC-T to free serum concentration differed considerably between T4 (16.6), T3 (24.4), and 3,3'-T2 (15.5) as compared to rT3 (5.8) and 3',5'-T2 (2.6). Data on three patients with thyroid diseases suggested that RBC-T values were increased in hyperthyroidism and decreased in hypothyroidism, whereas the cytosol/cytosol + membrane-ratio was unaltered.

[Incest and sexual abuse. A study among patients at a hospital for neuroses, Montebello]

A cross-sectional investigation on a day chosen at random i autumn 1987 in the Hospital for Neuroses, Montebello, Elsinore, revealed that a total of 25% of the female patients treated on that date had previously been the victims of incest (8.7%) or sexual abuse (17.3%). Of these, the great majority, 19 out of 23 (82%) had been abused prior to the age of 18 years. One out of 15 male patients (7%) had been the victim of previous sexual abuse. Approximately one third of the sexually abused women had been abused by more than one person. The incident had been reported to the police on one occasion only. In addition, previous incest/sexual abuse was presumed where further 10% of the female patients were concerned, on the basis of the opinions formed by the therapists from the clinical pictures and the case histories. In approximately half of the cases, the secrecy concerning the abuse was broken in the course of the psychotherapeutic process and it is concluded that frankness knowledge and courage on the part of the therapist are essential in order to establish sufficiently differentiated psychotherapeutic treatment and that increased knowledge about the problem in society will presumably exert a prophylactic effect.

Interleukin-1 affects the function of cultured human thyroid cells

Cytokines are peptide hormones essential for cellular communication in the immune response. The purpose of this study was to investigate the influence of cytokines, especially recombinant interleukin 1 beta (rIL-1 beta), on human thyroid cells. Thyroglobulin (Tg) was measured by a double antibody radioimmunoassay, and cyclic AMP (cAMP) by a competitive protein binding assay. Supernatants from unstimulated and phytohaemagglutinin-stimulated blood mononuclear cells were added to human thyroid cells cultured in monolayers. A dose-dependent inhibition of the secretion of Tg and cAMP was demonstrated. Both subcultured and primary cultured cells incubated with rIL-1 beta at pharmacological levels (10(-1)-10(2) U/ml) exhibited an inhibition of Tg and cAMP secretion, while at physiological levels (10(-5)-10(-3) U/ml), the secretion of Tg was enhanced. The similar stimulation of cAMP was demonstrated in subcultures. These in vitro studies suggest that IL-1 beta may play a role in the pathogenesis of autoimmune thyroid diseases. Further, the stimulations at low concentrations indicate that IL-1 beta may regulate the function of the thyroid gland under physiological conditions.

Thyroid function in patients with Pendred's syndrome

Thyroid function was studied in 17 unrelated patients with Pendred's syndrome. Fourteen patients had been treated with L-thyroxine, which was withdrawn during the investigation. Eight of the patients had previously had a thyroid resection. Thirteen patients had goiter at the time of study. The serum total thyroxine and serum total triiodothyronine concentrations were normal in 8, of whom 3 had elevated serum TSH concentrations. In the remaining 9 cases the thyroxine levels were below normal with elevated TSH. Serum reverse triiodothyronine concentrations were decreased in 8 out of 11. Median serum thyroglobulin was 973 micrograms/l (range 10.9-3200 micrograms/l) and increased in 13. Three patients had slightly positive thyroglobulin antibodies and one with normal level was thyrodectomized. Thyroid stimulating antibodies as measured by adenylate cyclase stimulation (median 114%, range 85-137%) were slightly increased in 11. When measured as TSH binding inhibiting immunoglobulins none were positive. Thyroid microsomal antibodies were negative in all. All patients with a detectable 131I uptake (n = 15) showed a pathological iodide perchlorate discharge test (median 32%, range 16-46%). These findings indicate an organification defect with impaired hormone synthesis.

The influence of free fatty acids on the free fraction of thyroid hormones in serum as estimated by ultrafiltration

Thyroid hormones are displaced from their binding proteins in serum during nonthyroidal somatic illness, and FFA have been claimed to contribute. It seems mandatory to evaluate this effect using techniques for the measurements of serum free thyroid hormones in which serum remains undiluted. We measured the effect of 7 common human FFA on the free fraction of T4, T3 and rT3 in serum from healthy subjects using an ultrafiltration technique by which serum is diluted only minimally. In addition we measured the effect of oleic acid on the free fractions of the iodothyronines in pooled serum from healthy subjects and in pooled serum from patients with nonthyroidal illness. All FFA tested were able to displace both T4, T3 and rT3, but to a varying degree, arachidonic and linoleic acid being the most potent ones. A 20% increase in the free fractions of T4, T3 and rT3, respectively, was obtained by adding between 1.7-3.3 mmol/l, 1.3-4.6 mmol/l and 1.0-2.4 mmol/l of the different FFA. A serum pool obtained from patients with nonthyroidal somatic illness was more sensitive to oleic acid than a serum pool obtained from healthy subjects, since 2-3 times less oleic acid was necessary to induce a 20% increase in the free fractions of thyroid hormones. It is concluded that FFA are able to displace both T4, T3 and rT3 from their serum binding proteins in healthy subjects as well as in patients with nonthyroidal illness. However, serum from patients with nonthyroidal illness was more sensitive to the displacing activity of oleic acid than serum from healthy subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationships between serum thyrotropin, serum free thyroxine (T4), and 3,5,3'-triiodothyronine (T3) and the daily T4 and T3 production rates in euthyroid patients with multinodular goiter

Serum TSH, as measured by a sensitive assay, and serum free T4 and T3, as measured by an ultrafiltration technique, were compared in 14 euthyroid patients with multinodular goiter and 14 normal subjects. T4 and T3 turnover studies also were performed, using the single injection, noncompartmental approach. The goitrous patients had serum free T3 levels within the normal range, but their median serum T3 level was increased compared to that in the normal subjects [goitrous patients, 5.48 pmol/L (range, 4.41-9.03); normal subjects, 4.12 pmol/L (range, 2.58-5.78); P less than 0.01]. The T3 production rate (PR) also was elevated in the patients (median, 39.4 nmol/day X 70 kg; range, 28.7-70.5) compared to that in the normal subjects 31.1 nmol/day X 70 kg; range, 24.4-45.2); P less than 0.05). No differences were found between the two groups with regard to serum free T4 levels or T4 PRs. Serum TSH levels in the patients were reduced (median, 0.20 mU/L; range, less than 0.05-1.6) compared to those in normal subjects (1.8 mU/L; range, 0.36-5.1; P less than 0.01). A significant inverse correlation was found between serum TSH levels and free T3 levels (r = 0.70; P less than 0.001), whereas serum TSH did not correlate with serum free T4 or the PR of T4 or T3. Our data suggest that clinically and biochemically euthyroid patients with multinodular goiter have slight T3 hyperproduction, and TSH secretion in the patients studied was more closely related to serum free T3 levels than to serum free T4 levels or the T3 or T4 PR.

Increased sympathetic tone in forearm subcutaneous tissue in primary hypothyroidism

Sympathetic reflex regulation of subcutaneous blood flow (SBF) in the forearm was studied in eight patients with primary hypothyroidism. Diastolic arterial pressure was greater than or equal to 95 mmHg in five patients. SBF was determined by local clearance of Na99mTcO4. Sympathetic vasoconstriction normally seen after lowering the forearm 40 cm below heart level was absent since SBF only decreased by 4% (+/- 7%, P greater than 0.1) during these conditions. In head-up vertical position we noticed a diminished baroreceptor response as SBF at heart level was reduced by 11% (+/- 7%, P greater than 0.1) compared to supine position. After proximal local anaesthesia SBF increased by 351% (+/- 81%, P less than 0.01) and disclosed a normal vasoconstrictor response as SBF was reduced by 53% (+/- 5%, P less than 0.01) during arm lowering. Five of the treated patients were restudied in the euthyroid state. Mean arterial pressure was reduced in mean by 20 mmHg (+/- 6 mmHg, P less than 0.02) during treatment and a significant vasoconstriction was observed both during arm lowering (SBF = -52% (+/- 6%, P less than 0.02)) and in head-up vertical position (SBF = -45% (+/- 11%, P less than 0.02)). In conclusion sympathetic vasoconstrictor activity in adipose tissue is markedly increased in primary hypothyroidism. Sympathetic tone and arterial pressure are reduced during treatment.

Serum lipids in hyper- and hypothyroidism before and after treatment

Total cholesterol (TC), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), triglycerides (TG) and apoprotein A (Apo A) were determined in serum from 21 hyperthyroid patients and 11 hypothyroid patients before and after treatment to euthyroid state. The above-mentioned components were also determined in a reference population. In the hyperthyroid group the concentration of total cholesterol and low density lipoprotein-cholesterol increased significantly upon treatment. High density lipoprotein also increased except for 9 patients also receiving propranolol. The ratio between high density lipoprotein-cholesterol and total cholesterol decreased in the patients receiving propranolol. In the hypothyroid group the values after treatment decreased significantly for cholesterol, high density lipoprotein-cholesterol and low density lipoprotein-cholesterol. The ratio between high density lipoprotein-cholesterol and total cholesterol was unchanged.