The Chemical Synthesis of Knob Domain Antibody Fragments

Cysteine-rich knob domains found in the ultralong complementarity determining regions of a subset of bovine antibodies are capable of functioning autonomously as 3-6 kDa peptides. While they can be expressed recombinantly in cellular systems, in this paper we show that knob domains are also readily amenable to a chemical synthesis, with a co-crystal structure of a chemically synthesized knob domain in complex with an antigen showing structural equivalence to the biological product. For drug discovery, following the immunization of cattle, knob domain peptides can be synthesized directly from antibody sequence data, combining the power and diversity of the bovine immune repertoire with the ability to rapidly incorporate nonbiological modifications. We demonstrate that, through rational design with non-natural amino acids, a paratope diversity can be massively expanded, in this case improving the efficacy of an allosteric peptide. As a potential route to further improve stability, we also performed head-to-tail cyclizations, exploiting the proximity of the N and C termini to synthesize functional, fully cyclic antibody fragments. Lastly, we highlight the stability of knob domains in plasma and, through pharmacokinetic studies, use palmitoylation as a route to extend the plasma half-life of knob domains in vivo. This study presents an antibody-derived medicinal chemistry platform, with protocols for solid-phase synthesis of knob domains, together with the characterization of their molecular structures, in vitro pharmacology, and pharmacokinetics.

Pathogenic Role of Circulating Citrullinated Antigens and Anti-Cyclic Monoclonal Citrullinated Peptide Antibodies in Rheumatoid Arthritis

We examined whether it is possible to directly detect citrullinated antigens in the serum of rheumatoid arthritis (RA) patients using a monoclonal antibody (mAb) designed to be specific for citrullinated peptides. In order to confirm the potential of the mAb as a direct arthritis-inducing substance through experimental model of RA, a monoclonal antibody (mAb) 12G1 was generated using by immunization of mice with a challenging cyclic citrullinated peptide. Immunohistochemical analysis of RA-affected synovial tissue showed that our mAb 12G1 could indeed detect citrullinated proteins in target tissues. Subsequently, serum levels of citrullinated type II collagen and filaggrin were measured in healthy volunteers, patients with RA, ankylosing spondylitis (AS), and systemic lupus erythematosus (SLE) using a 12G1-based sandwich ELISA. This showed that citrullinated filaggrin showed 78.9% sensitivity and 85.9% specificity for RA diagnosis with a cutoff optical density (OD) value of 1.013, comparable with the results from a second-generation anti-citrullinated protein antibody (ACPA) test. Circulating citrullinated collagen and filaggrin were detected even in sera of RA patients who were negative for both rheumatoid factor (RF) and ACPA. ELISA results also showed that RF and ACPA titers showed significantly positive correlation with both citrullinated collagen and filaggrin OD values in sera of RA patients. 12G1 challenging aggravated the severity of murine arthritis. In summary, mAb 12G1 can directly detect citrullinated proteins in RA target tissue and in sera of RA patients and 12G1 showed direct arthritogenic potential in vivo. This, 12G1 might be useful for diagnosis of RA including seronegative RA and may help to elucidate the pathophysiological role of citrullination in RA.

Increased Gene Copy Number of DEFA1A3 Is Associated With the Severity of Ulcerative Colitis

INTRODUCTION

DEFA1A3 encodes human neutrophil peptides (HNPs) 1-3 and has multiple copy number variations (CNVs). HNPs are associated with innate immunity. Ulcerative colitis (UC), a chronic inflammatory gastrointestinal disorder, is a life-threatening condition, and predictive markers of UC severity are needed. This study investigated the relationship between DEFA1A3 CNV and UC severity.

METHODS

This study enrolled 165 patients with UC. The relationship between DEFA1A3 CNV and disease severity was analyzed based on Mayo score, patient characteristics, and treatment methods. In addition, serum and stimulated neutrophil-derived HNP concentrations were also measured in patients with high and low DEFA1A3 CNV.

RESULTS

DEFA1A3 CNV was significantly correlated with Mayo score and white blood cell count (R = 0.46, P < 0.0001; R = 0.29, P = 0.003, respectively), and only high copy numbers of DEFA1A3 were independent factors for severe UC (P < 0.001, odds ratio: 1.88, 95% confidence interval, 1.34-2.61). The number of severe UC patients with high DEFA1A3 CNV was significantly greater than those with low CNV. We confirmed the associations between DEFA1A3 and UC severity using a validation cohort. In addition, the HNP concentration in high-copy number patients was significantly higher after neutrophil stimulation than that in low-copy number patients.

DISCUSSION

This study demonstrated that there is a correlation between DEFA1A3 copy number and severity in patients with UC. In addition, neutrophils from UC patients with higher DEFA1A3 CNV had high reactivity of secretion of HNPs after stimulation. DEFA1A3 CNV may be a novel severity marker and a potential therapeutic target for UC.

A MIF-Derived Cyclopeptide that Inhibits MIF Binding and Atherogenic Signaling via the Chemokine Receptor CXCR2

Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine and atypical chemokine with a key role in inflammatory diseases including atherosclerosis. Key atherogenic functions of MIF are mediated by noncognate interaction with the chemokine receptor CXCR2. The MIF N-like loop comprising the sequence 47-56 is an important structural determinant of the MIF/CXCR2 interface and MIF(47-56) blocks atherogenic MIF activities. However, the mechanism and critical structure-activity information within this sequence have remained elusive. Here, we show that MIF(47-56) directly binds to CXCR2 to compete with MIF receptor activation. By using alanine scanning, essential and dispensable residues were identified. Moreover, MIF(cyclo10), a designed cyclized variant of MIF(47-56), inhibited key inflammatory and atherogenic MIF activities in vitro and in vivo/ex vivo, and exhibited strongly improved resistance to proteolytic degradation in human plasma in vitro, thus suggesting that it could serve as a promising basis for MIF-derived anti-atherosclerotic peptides.

Occurrence of anti-CCP2 and RF isotypes and their relation to age and disease severity among Sudanese patients with rheumatoid arthritis

OBJECTIVE

Anti-cyclic citrullinated peptide 2 antibodies (anti-CCP2) and rheumatoid factor (RF) in rheumatoid arthritis (RA) has been extensively assessed in industrialized countries. We investigated the diagnostic and prognostic impact of anti-CCP2 and RF isotypes in a Sudanese cross-sectional RA cohort.

METHODS

Consecutive RA patients (n = 281) diagnosed according to the 1987 ACR criteria were included 2008-2010. Anti-CCP2 and RF isotypes (IgA, IgM, and IgG) were measured by enzyme immunoassay in 262 patients, with reference intervals aligned to the same diagnostic specificity as for anti-CCP2 (97.6%) using national controls.

RESULTS

IgA RF was the predominant RA-associated autoantibody (56%), followed by IgM RF and anti-CCP2 (both 52%) and IgG RF (49%). In receiver operator characteristic analysis, IgA RF also showed the largest area under the curve. Patients with IgG RF were younger and had 8 years lower median age of disease onset compared to antibody negative patients (p < 0.0001). IgG RF was the only marker associated with a high number of involved joints (p = 0.028), and together with anti-CCP2 were the strongest markers for finger deformities (p = 0.016 and p = 0.012), respectively. No statistical differences were found for disease duration, ESR and Hb levels, and occurrence of erosions/osteopenia for any of the investigated autoantibodies.

CONCLUSION

Whereas IgA RF showed the best diagnostic performance, IgG RF associated with low age of RA onset, high number of involved joints, and finger deformities. These findings indicate that RA-associated antibodies other than conventional IgM RF and anti-CCP2 might be informative in non-Caucasian RA populations.

Investigation of the Potential Use of Sialic Acid as a Biomarker for Rheumatoid Arthritis

BACKGROUND

Sialic acids are a diverse family of sugar units attached to the outermost ends of sugar chains, which were demonstrated to be related to many diseases. We hypothesized sialic acids could be used as biomarkers for diagnosis of rheumatoid arthritis (RA).

METHODS

The serum level of the main sialic acids, N-acetyl-D-neuraminic acid (Neu5Ac) in 163 RA patients and 50 healthy individuals were detected by pre-column derivatization-high performance liquid chromatography method. And three biomarkers to diagnose RA in clinic, C-reactive protein (CRP), rheumatoid factor (RF), and cyclic citrullinated peptides (CCP) in serum of these subjects were analyzed using enzyme-linked immunosorbent assay (ELISA). The data was analyzed using the receiver operating characteristic (ROC) curve and the Youden index.

RESULTS

We found the concentration of Neu5Ac in RA group was significantly higher than healthy group. There was a positive correlation between the concentration of Neu5Ac and the RA disease activity score (DAS). The sensitivity and specificity of Neu5Ac were significantly greater than CRP, RF, CCP.

CONCLUSIONS

Higher serum levels of Neu5Ac were significantly associated with the presence as well as severity of RA. Neu5Ac may be a potential biomarker for prediction and severity of RA in clinical practice.

Porphyromonas gingivalis experimentally induces periodontis and an anti-CCP2-associated arthritis in the rat

OBJECTIVES

Association between periodontal disease (PD) and rheumatoid arthritis (RA) has been extensively described, but direct evidence of causal involvement of PD in RA is missing. We investigated the priming role of oral Porphyromonas gingivalis (P. gingivalis) in PD and subsequent RA and we assessed biomarkers of bone resorption and arthritis development in rats.

METHODS

Lewis rats were orally exposed to either P. gingivalis, Prevotella intermedia or control gel for 1 month and then followed for 8 months. The onset and development of PD was assessed by serology, gingivitis severity and micro-CT (µCT). We investigated arthritis development using circulating proinflammatory markers, anticyclic citrullinated peptide (CCP), anticitrullinated protein antibody (ACPA), ankle histology and µCT.

RESULTS

PD was only observed in the P. gingivalis treated rats, as early as 1 month postexposure. Joint and systemic inflammation were detected only in the P. gingivalis group after 4 and 8 months. At 8 months, inflammatory cell infiltrate was observed in ankle joints and paralleled cortical erosions and overall cortical bone reduction. Furthermore, anti-CCP2 correlated with local and systemic bone loss.

CONCLUSIONS

In our long-term study, PD induced by oral exposure to P. gingivalis triggered seropositive arthritis, with systemic inflammation and bone erosions. This is the first in vivo demonstration of arthritis induced by oral priming with P. gingivalis.

Supplementation of Blackcurrant Anthocyanins Increased Cyclic Glycine-Proline in the Cerebrospinal Fluid of Parkinson Patients: Potential Treatment to Improve Insulin-Like Growth Factor-1 Function

Background: Insulin-like growth factor-1 (IGF-1) function is impaired in Parkinson disease. Cyclic glycine-proline (cGP), a metabolite of IGF-1, is neuroprotective through improving IGF-1 function. Parkinson disease patients score lower on Hospital-associated Anxiety and Depression Scale after supplementing blackcurrant anthocyanins (BCA), which may be associated with IGF-1 function. We evaluated the changes of cGP and IGF-1 before and after the supplementation. Methods: Plasma and cerebrospinal fluid (CSF) were collected from 11 male patients before and after 28 day supplementation of BCA. The concentrations of IGF-1, IGF binding protein (IGFBP)-3, and cGP were measured using ELISA and HPLC-MS assays. The presence of cGP in the BCA was evaluated. Results: cGP presented in the BCA. BCA supplementation increased the concentration of cGP (p < 0.01), but not IGF-1 and IGFBP-3 in the CSF. CSF concentration of cGP was correlated with plasma concentration of cGP (R = 0.68, p = 0.01) and cGP/IGF-1 molar ratio (R = 0.66, p = 0.01). The CSF/plasma ratio was high in cGP and low in IGF-1 and IGFBP-3. Conclusion: cGP is a natural nutrient to the BCA. The increased CSF cGP in Parkinson disease patients may result from the central uptake of plasma cGP. Given neurotrophic function, oral availability, and effective central uptake of cGP, the BCA has the potential to be developed to treat neurological conditions with IGF-1 deficiency.

The role for cyclic Glycine-Proline, a biological regulator of insulin-like growth factor-1 in pregnancy-related obesity and weight changes

Cyclic Glycine-Proline (cGP) regulates the homeostasis of insulin-like growth factor (IGF)-1 function and cGP/IGF-1 ratio determines IGF-1 bioactivity in vitro and in vivo. Plasma IGF-1 represents largely inactive IGF-1 and weakly associated with human obesity and hypertension. We evaluated the regulatory role for cGP in pregnancy-related obesity and hypertension, and in obesity status between pregnancy and postpartum. Women were recruited in their first pregnancy. A cross-sectional study compared plasma concentration of cGP, IGF-1 and IGF binding protein (IGFBP)-3 in women with obesity and/or hypertension to normal controls 6-year postpartum using UPLC-MS and ELISA. A longitudinal study compared the changes of these peptides from 15-week gestation to 6-year post-partum in the women who remained normal weight, remained obese or changed to obese or to normal respectively. Study 1 is a cross-sectional study. The obese group had lower IGF-1(p = 0.001), higher cGP/IGF-1 ratio (p = 0.0055) and the hypertensive group had lower IGFBP-3 (p = 0.046) and cGP (p = 0.043) than the controls. Study 2 is a longitudinal study. Women with weight loss had increased cGP/IGF-1 ratio (p = 0.0026) and decreased IGFBP-3 (p = 0.0001) compared with women whose weight remained normal. Women with weight gain had lower IGFBP-3 (p less than 0.0001) only. Women who remained obese had increased cGP/IGF-1 ratio (p = 0.006) only. Increase in cGP/IGF-1 ratio is associated with obesity, but not hypertension. Changes of IGFBP-3 and/or cGP/IGF-1 ratio are associated with weight changes. The data suggest the role for cGP in obesity through autocrine regulation of IGF-1.

Comparative evaluation of treatment patterns and healthcare utilization of newly-diagnosed rheumatoid arthritis patients by anti-cyclic citrullinated peptide antibody status

BACKGROUND

Anti-cyclic citrullinated peptide (CCP) antibody positivity is an established diagnostic factor for severe disease activity and joint damage and a prognostic factor for aggressive disease in rheumatoid arthritis (RA).

OBJECTIVE

To compare RA-related treatment, healthcare utilization, and joint erosion between anti-CCP-positive and anti-CCP-negative RA patients.

METHODS

Newly-diagnosed RA patients were identified from the Henry Ford Health System database between January 1, 2009 and December 31, 2014; the date of the first RA diagnosis within the study period was the index date. Baseline anti-CCP test was used to categorize patients as anti-CCP-positive or anti-CCP-negative, and outcomes were evaluated in the 6 months post-index.

RESULTS

There were 217 anti-CCP-positive and 191 anti-CCP-negative RA patients included in the study. A higher proportion of anti-CCP-positive patients were initiated on RA treatment than anti-CCP-negative patients (70.5% vs 23.0%; p < .0001). More anti-CCP-positive patients received methotrexate (73.2% vs 56.8%; p = .0374), while more anti-CCP-negative patients received hydroxychloroquine (31.8% vs 13.1%; p = .0037) in first-line therapy. A higher proportion of anti-CCP-negative patients were tested for rheumatoid factor (RF) and erythrocyte sedimentation rate (ESR). Of those tested, there were more positive test results in the anti-CCP-positive cohort compared to the anti-CCP-negative cohort (RF: 84.4% vs 18.2%, p < .0001; C-reactive protein [CRP]: 69.7% vs 48.3%, p = .0008; and ESR: 89.5% vs 53.9%, p < .0001). Outpatient utilization predominated, with more anti-CCP-positive patients having any outpatient physician office visit (96.3% vs 77.5%, p < .0001) and a higher mean number of visits (5.3 vs 2.5, p < .0001) than anti-CCP-negative patients. Among anti-CCP-positive (n = 113) and anti-CCP-negative (n = 58) patients with imaging results, more anti-CCP-positive patients had joint erosion compared to anti-CCP-negative patients (18.6% vs 8.6%; p = .0858); however, statistical significance was not reached.

CONCLUSION

RA patients with positive anti-CCP antibodies had higher degrees of inflammation and disease activity as indicated by laboratory results, which likely contributed to their higher rates of healthcare utilization, joint erosion, and proportions of RA treatment.

Serum levels of matrix metalloproteinase-3 and autoantibodies related to rheumatoid arthritis in the general Japanese population and their association with osteoporosis and osteoarthritis: the ROAD study

To purpose of this study was to reveal the mean levels and positive proportion of serological markers related to rheumatoid arthritis, and clarify their relationship with osteoporosis and hand osteoarthritis (OA). A total of 1546 participants from the third survey of the research on osteoarthritis/osteoporosis against disability study were enrolled in the current study. Using participant blood samples, the levels of anti-cyclic citrullinated protein (CCP) antibody, rheumatoid factor (RF), matrix metalloproteinase-3 (MMP-3), C-reactive protein (CRP), and high-sensitivity CRP (hsCRP) were measured. Subjects with higher than normal levels were defined as being positive. Osteoporosis was defined according to the recommendations set by World Health Organization criteria in 1994. Radiographic hand OA was evaluated using the modified Kellgren-Lawrence (KL) scale. The positive proportion of anti-CCP antibody, RF, MMP-3, CRP, and hsCRP was 1.8, 7.1, 15.0, 6.7, and 6.4%, respectively. MMP-3 was associated with age, and was significantly higher in men than in women. Positive MMP-3 was not significantly related to osteoporosis or severe hand OA (KL grade ≥3) after adjustment for other factors including age, sex, and body mass index. The results from this study clarified the values and positive proportion of RA-related markers and revealed their relationship with osteoporosis and hand OA.

Smoking and susceptibility to rheumatoid arthritis in a Swedish population-based case-control study

Smoking is one of the most established risk factors for rheumatoid arthritis (RA). The aim of this study was to estimate how age at smoking debut, smoking cessation, duration, intensity, and cumulative dose of smoking influence the risk of developing anti-citrullinated peptide antibodies (ACPA) positive and ACPA negative RA. The present report is based on a Swedish population-based, case–control study with incident cases of RA (3655 cases, 5883 matched controls). Using logistic regression models, subjects with different smoking habits were compared regarding risk of developing the two variants of RA, by calculating odds ratios (OR) with 95% confidence intervals (CI). Smoking increased the risk of developing both ACPA positive (OR 1.9, 95% CI 1.7–2.1) and ACPA negative RA (OR 1.3, 95% CI 1.2–1.5). For both subsets of RA, there seemed to be a threshold (~ 2.5 pack years for ACPA positive RA and ~ 5 pack years for ACPA negative RA) below which no association between smoking and RA occurred. A dose–response association was observed between cumulative dose of smoking and risk of developing ACPA positive RA (p value for trend < 0.0001). Duration of smoking had a higher influence on the association between smoking and RA than did intensity of smoking. For both subsets of RA, the detrimental effect of smoking decreased after smoking cessation. Twenty years after smoking cessation, there was no longer an association between smoking and risk of ACPA negative RA, whereas the association between smoking and ACPA positive RA risk persisted and was dependent on the cumulative dose of smoking. Smoking increases the risk of both subsets of RA with a more pronounced influence on the risk of ACPA positive RA. Preventive measures in order to reduce smoking are essential and may result in a decline in RA incidence.

Rheumatoid disease: an unusual cause of relapsing meningoencephalitis

A 73-year-old man presented with three episodes of dysphasia and disinhibited behaviour, a single seizure and transient ischaemic attack-like events characterised by right arm and/or leg weakness. These episodes were separated by month-long asymptomatic intervals. Medical history included rheumatoid arthritis, which was clinically quiescent on leflunomide.Repeated cerebrospinal fluid examination showed a persistent lymphocytosis with mildly reduced glucose and elevated protein; oligoclonal bands and viral PCR were negative. MRI of the brain was initially normal, but 7 months after initial presentation revealed meningeal enhancement with bifrontal cortical hyperintensities on T2/fluid-attenuated inversion recovery. Brain biopsy demonstrated necrotising granulomatous meningitis with mixed T cell and B cell infiltrates and without evidence of vasculitis or infection. Serum anticyclic citrullinated peptide antibodies were strongly positive.The diagnosis of rheumatoid meningoencephalitis was made on the basis of brain biopsy findings and serological evidence of active rheumatoid disease. Steroids and rituximab therapy were started leading to clinical stabilisation.

Enhanced Permeability and Binding Activity of Isobutylene-Grafted Peptides

We present a new peptide-macrocyclization strategy with an isobutylene graft. The reaction is mild and proceeds rapidly and efficiently both for linear and cyclic peptides. The resulting isobutylene-grafted peptides possess improved passive membrane permeability due to the shielding of the polar backbone of the amides, as demonstrated by NMR spectroscopy and molecular dynamics simulations. The isobutylene-stapled structures are fully stable in human plasma and in the presence of glutathione. This strategy can be applied to bioactive cyclic peptides such as somatostatin. Importantly, we found that structural preorganization forced by the isobutylene graft leads to a significant improvement in binding. The combined advantages of directness, selectivity, and smallness could allow application to peptide macrocyclization based on this attachment of the isobutylene graft.

In Vitro and In Vivo Study of the Gastrointestinal Absorption and Metabolisation of Hymenocardine, a Cyclopeptide Alkaloid

Hymenocardine is a cyclopeptide alkaloid present in the root bark of Hymenocardia acida. In traditional African medicine, the leaves and roots of this plant are used to treat malaria, and moderate in vitro antiplasmodial activity has been reported for hymenocardine. However, in view of its peptide-like nature, potential metabolisation after oral ingestion has to be taken into account when considering in vivo experiments. In this study, the stability and small intestinal absorption of hymenocardine was assessed using an in vitro gastrointestinal dialysis model. In addition, potential liver metabolisation was investigated in vitro by incubation with a human S9 fraction. Moreover, hymenocardine was administered to rats per os, and blood and urine samples were collected until 48 and 24 h after oral administration, respectively. All samples resulting from these three experiments were analyzed by LC-MS. Analysis of the dialysate and retentate, obtained from the gastrointestinal dialysis model, indicated that hymenocardine is absorbed unchanged from the gastrointestinal tract, at least in part. After S9 metabolisation, several metabolites of hymenocardine could be identified, the major ones being formed by the reduction and/or the loss of an N-methyl group. The in vivo study confirmed that hymenocardine is absorbed from the gastrointestinal tract unchanged, since it could be identified in both rat plasma and urine, together with hymenocardinol, its reduction product.

Design, synthesis and structure-activity relationship study of wollamide B; a new potential anti TB agent

Wollamide B is a cationic antimycobacterial cyclohexapeptide that exhibits activity against Mycobacterium bovis (M. bovis) (IC₅₀ of 3.1 μM). Aiming to define its structural activity relationship (SAR), optimizing potency and pharmacokinetic properties, libraries of analogues were synthesized following a standard Fmoc-based solid phase peptide synthesis approach. The antimycobacterial activities of wollamide B and all the synthesized analogues were tested against Mycobacterium tuberculosis (Mtb) H37Rv. Parallely, in vitro drug metabolism and pharmacokinetic (ADME) profiling was done for the synthesized compounds to evaluate their drug likeness. Among the 25 synthesized wollamides five of them showed potent activities with MICs ≤ 3.1 μM and found to be nontoxic against human HepG2 cells up to 100 μM. The results of the in vitro ADME profiling revealed the remarkable plasma stability and very good aqueous solubility of the class in general while the metabolic stability was found to be moderate to low. Of particular note, compounds 7c (MIC = 1.1 μM) and 13c (0.6 μM) that exhibited good balance of antimycobacterial activity vs. optimal pharmacokinetic properties could be used as a new lead for further development.

A Simple and High-Throughput Analysis of Amatoxins and Phallotoxins in Human Plasma, Serum and Urine Using UPLC-MS/MS Combined with PRiME HLB μElution Platform

Amatoxins and phallotoxins are toxic cyclopeptides found in the genus Amanita and are among the predominant causes of fatal food poisoning in China. In the treatment of Amanita mushroom poisoning, an early and definite diagnosis is necessary for a successful outcome, which has prompted the development of protocols for the fast and confirmatory determination of amatoxins and phallotoxins in human biological fluids. For this purpose, a simple, rapid and sensitive multiresidue UPLC-MS/MS method for the simultaneous determination of α-amanitin, β-amanitin, γ-amanitin, phalloidin (PHD) and phallacidin (PCD) in human plasma, serum and urine was developed and validated. The diluted plasma, serum and urine samples were directly purified with a novel PRiME technique on a 96-well μElution plate platform, which allowed high-throughput sample processing and low reagent consumption. After purification, a UPLC-MS/MS analysis was performed using positive electrospray ionization (ESI+) in multiple reaction monitoring (MRM) mode. This method fulfilled the requirements of a validation test, with good results for the limit of detection (LOD), lower limit of quantification (LLOQ), accuracy, intra- and inter-assay precision, recovery and matrix effects. All of the analytes were confirmed and quantified in authentic plasma, serum and urine samples obtained from cases of poisoning using this method. Using the PRiME μElution technique for quantification reduces labor and time costs and represents a suitable method for routine toxicological and clinical emergency analysis.

Serum Immunoglobulin G Levels to Porphyromonas gingivalis Peptidylarginine Deiminase Affect Clinical Response to Biological Disease-Modifying Antirheumatic Drug in Rheumatoid Arthritis

OBJECTIVES

To determine whether serum immunity to Porphyromonas gingivalis peptidylarginine deiminase (PPAD) affects the clinical response to biological disease-modifying antirheumatic drug (bDMARD) in patients with rheumatoid arthritis (RA).

METHODS

In a retrospective study, rheumatologic and periodontal conditions of 60 patients with RA who had been treated with conventional synthetic DMARD were evaluated before (baseline) and after 3 and 6 months of bDMARD therapy. After serum levels of anti-PPAD immunoglobulin G (IgG) were determined at baseline, the patients were respectively divided into two groups for high and low anti-PPAD IgG titers according to the median measurements. Genotypes at 8 functional single nucleotide polymorphisms (SNPs) related to RA were also determined.

RESULTS

After 3 and 6 months of therapy, patients with low anti-PPAD IgG titers showed a significantly greater decrease in changes in the Disease Activity Score including 28 joints using C-reactive protein (DAS28-CRP) (P = 0.04 for both) and anti-cyclic citrullinated peptide (CCP) IgG levels (P = 0.03 and P = 0.04) than patients with high anti-PPAD IgG titers, although these parameter values were comparable at baseline. The anti-PPAD IgG titers were significantly positively correlated with changes in the DAS28-CRP (P = 0.01 for both) and the anti-CCP IgG levels (P = 0.02 for both) from baseline to 3 and 6 months later. A multiple regression analysis revealed a significantly positive association between the anti-PPAD IgG titers and changes in the DAS28-CRP after 6 months of bDMARD therapy (P = 0.006), after adjusting for age, gender, smoking, periodontal condition, and RA-related SNPs.

CONCLUSION

The serum IgG levels to PPAD affect the clinical response to bDMARD in patients with RA.

[ASSOCIATION OF CYCLIC CITRULLINATED PEPTIDE ANTIBODIES LEVEL WITH RHEUMATOID ARTHRITIS ACTIVITY BASED ON GLUCOCORTICOID RECEPTOR GENE BBL1 POLYMORPHISM]

The ambiguity of facts on connection between glucocorticoid receptor gene (GR) Bcl1 polymorphism in rheumatoid arthritis (RA) and its activity as well as lack of facts on its association with serological variants of the desease, makes ir reasonable to investigate its connections between cyclic citrullinated peptide antibodiss (ACCP) concentration and clinico-laboratorial parameters of RA (DAS 28 desease activity score, C-reactive protein concentration (CRP) and erythrocyte sedimentation rate (ESR) level based on GR gene Bcl1 polymorphism. Study involved 161 RA patients aged over 40 as well as 96 healthy individuals. Routine examination of RA diagnostics, anthropometric and molecular genetic methods were used in the research. Statistical analysis of the results was performed using SPSS-17 program. It has been proved that there is no significant difference in GR gene Bcl1 polymorphism distribution based on DAS 28 RA desease activity score, ACCP concentration and ESR level. However, we have found out that G/G genotype bearers have positive correlation relationship between ACCP titre and RA activity by laboratorial parameters (CRP, ESR),DAS 28 score and rheumatoid factor (RF) which has not been found in C/C and C/G genotype bearing patients. The above indicates the association of G/G genotype by GR gene Bcl1 polymorphism with clinico-laboratorial parameters of RA inflammatory activity. In course of the study we have identified the existance of correlation relationship between ACCP concentration and DAS 28 score of RA activity, CRP concentration and ESR level in individuals bearing G/G gene by GR gene Bcl11 polymorphism gene. The association between GR gene Bcl1 polymorphism and clinico-laboratorial parameters of RA inflammatory activity has not been found.

Prophylactic Injection of Recombinant Alpha-Enolase Reduces Arthritis Severity in the Collagen-Induced Arthritis Mice Model

Objective

To evaluate the ability of the glycolytic enzyme alpha-enolase (ENO1) or its immunodominant peptide (pEP1) to reduce the severity of CIA in DBA/1 mice when injected in a prophylactic way.

Methods

Mice were treated with mouse ENO1 or pEP1 one day prior to collagen II immunization. Clinical assessment was evaluated using 4 parameters (global and articular scores, ankle thickness and weight). Titers of serum anti-ENO1, anti-cyclic citrullinated peptides (anti-CCP) and anti-CII (total IgG and IgG1/IgG2a isotypes) antibodies were measured by ELISA at different time-points. Disease activity was assessed by histological analysis of both anterior and hind paws at the end of experimentation.

Results

Prophylactic injection of 100 μg of ENO1 reduced severity of CIA. Serum levels of anti-CII antibodies were reduced in ENO1-treated mice. Concordantly, ENO1-treated mice joints presented less severe histological signs of arthritis. ENO1 did not induce a shift toward a Th2 response since IgG1/IgG2a ratio of anti-CII antibodies remained unchanged and IL-4 serum levels were similar to those measured in the control group.

Conclusions

Pre-immunization with ENO1 or its immunodominant peptide pEP1 reduces CIA severity at the clinical, immunological and histological levels. Effects of pEP1 were less pronounced. This immunomodulatory effect is associated with a reduction in anti-CII antibodies production but is not due to a Th1/Th2 shift.

The ITGAV-rs3911238 polymorphism is associated with disease activity in rheumatoid arthritis

Evidences indicate that angiogenesis is an important process in the development of destructive synovial tissue in rheumatoid arthritis (RA). Recently, it has been shown that the polymorphism of the integrin-αv subunit encoded by the ITGAV gene plays a role in angiogenesis and is considered as RA susceptibility loci. This study investigated association of four single nucleotide polymorphisms (SNPs) in ITGAV with disease activity score (DAS28), serum levels of C-reactive protein (CRP), and anti-cyclic citrullinated peptide(anti-CCP) antibody in 419 RA patients and 398 healthy individuals. Four SNPs in ITGAV gene (rs3911238, rs3738919, rs10174098 and rs3768777) were analyzed. Serum concentrations of anti-CCP antibody and CRP were measured by ELISA. We used the EULAR activity criteria to calculate DAS28-CRP. Among these SNPs, the ITGAV-rs3911238-G/C polymorphism was associated with RA disease activity [remission-to-low and moderate-to-high in codominant model (CC vs.GG: OR=1.53, p=0.041 and allele (C vs. G: OR=1.18, p=0.042)] and presence of anti-CCP (codominant CC vs.GG: OR=2.77, p=0.001, allele C vs. G: OR=1.19,p=0.033). The carriers of CC genotype ITGAV-rs3911238 had higher serum levels of CRP and anti-CCP antibody titer and higher ESR and disease activity score than carriers of GG and CG genotypes. Furthermore, haplotypes analysis showed that ITGAV rs3733891C/rs3768777T/rs3911238C/rs10174098A and ITGAV rs3733891A/rs3768777T/rs3911238G/rs10174098A haplotypes increased severity and anti-CCP antibody in RA patients (OR=5.54, p=0.049 and OR=2.89; p=0.024, respectively) in comparison with ITGAV rs3733891C/rs3768777T/rs3911238G/rs10174098A haplotypes. Thus, the present study demonstrated that the link between systemic inflammatory markers and the ITGAV-rs3911238 polymorphism allele in Iranian RA patients.

Expression of the inherently autoreactive idiotope 9G4 on autoantibodies to citrullinated peptides and on rheumatoid factors in patients with early and established rheumatoid arthritis

BACKGROUND

The pre-symptomatic stage of Rheumatoid arthritis (RA) is associated with pro-inflammatory cytokines and autoantibodies. High levels and epitope spread by Rheumatoid factors (RhF) and autoantibodies to citrullinated proteins signify progression towards disease expression. In established RA, the persistence of high autoantibody levels reflects production by both long-lived plasma cells and short-lived plasmablasts. Neither the relative contributions to pathogenesis by autoantibodies from either source, nor the factors responsible for deciding the fate of autoantigen specific 'parent' B-cells, is understood. Phenotypic markers identifying subsets of autoreactive B-cells are therefore of interest in understanding the origin and perpetuation of the autoimmune response in RA. One such phenotypic marker is the rat monoclonal antibody, 9G4, which recognises an idiotope on immunoglobuins derived from the inherently autoreactive VH-gene, VH4-34. We therefore investigated whether the 9G4 idiotope was expressed on autoantibodies in patients with RA.

METHODOLOGY/PRINCIPAL FINDINGS

Sera from 19 patients with established RA and those with <1year history of untreated polyarthritis either resolving into RA (n = 42) or non-RA diagnosis (n = 31) were included. Autoantibodies to cyclic citrullinated peptides (CCP), RhF and co-expression of the 9G4 idiotope were measured by ELISA. 9G4 recognised a population of anti-CCP antibodies in the majority of sera from patients with established disease and also in samples from patients with early disaese. 9G4+RhF levels were generally lower and not associated with positivity for, or levels of 9G4+CCP.

CONCLUSIONS/SIGNIFICANCE

The persistence of 9G4+ immunoglobulins, of any isotype, in serum is rare. We describe here the novel finding of 9G4 expression on anti-CCP antibodies in patients from the earliest symptoms of RA through to established disease. Our results suggest that 9G4 expression on anti-CCP autoantibodies was not due to polyclonal expansion of VH4-34-encoded immunoglobulins. These studies may therefore provide a new focus for investigation into the evolution of the autoimmune response in RA patients.

A transient peak of infections during onset of rheumatoid arthritis: a 10-year prospective cohort study

OBJECTIVES

The role of infection in rheumatoid arthritis (RA) has not been determined. We aimed to document the infectious burden and some aspects of antibacterial immunity in a large and prospective cohort study of RA patients in the early and late stages of the disease and in their relatives predisposed to RA.

SETTING

Clinical and laboratory examination of all individuals enrolled in the study was performed in the Republican Clinical Hospital, Kazan, Russia.

PARTICIPANTS

376 patients with RA, 251 healthy first-degree relatives and 227 healthy controls without a family history of autoimmune disease (all females) were examined twice annually over more than 10 years.

PRIMARY AND SECONDARY OUTCOME MEASURES

The following parameters were investigated: type, duration and frequency of infections, bacterial colonisation and serum levels of IgG to bacteria, serum levels of total Ig, plasma cytokine levels, granulocyte reactive oxygen species production, lysozyme activity and phagocytosis.

RESULTS

There were no significant differences in infection rate between healthy controls (median 14 days/year) and RA patients (13). However, infection rates were higher (p<0.001) in healthy relatives (53) and early stage patients (62), which groups also showed heavy bacterial skin colonisation. In contrast, late stage patients had fewer infection days (12; p<0.001) than healthy controls, although bacterial colonisation was still heavy. Phagocyte function and antibacterial antibody generation, together with compensatory cytokine production, were observed to be subnormal in the healthy relatives as well as in RA patients.

CONCLUSIONS

We observed a marked increase in overall infections at the time of RA onset, and signs of a defective antibacterial defence mechanism, contrasting with fewer infections in the late RA stage. It can be speculated that frequent early infections initiate a compensatory immune hyper-reactivity which reduces the infection load while stimulating the development of RA in predisposed individuals.

Rheumatoid factor and anti-CCP do not predict progressive joint damage in patients with early rheumatoid arthritis treated with prednisolone: a randomised study

OBJECTIVE

To analyse if predictors of radiographic progression differ between patients treated with or without prednisolone in early rheumatoid arthritis (RA). Radiographs of hands and feet were assessed using the modified Sharp/van der Heijde score and radiographic progression was defined as an increase in the total Sharp score above 5.8 (the smallest detectable change).

DESIGN

Prospective, randomised study of patients with early RA.

SETTING

Secondary level of care; six participating centres from southern Sweden; both urban and rural populations.

PARTICIPANTS

In all, 225 patients, 64% women, with a diagnosis of RA according to the American College of Rheumatology criteria, were included if they were between 18 and 80 years of age and had a disease duration of less than 1 year.

INTERVENTION

The patients were randomised to 7.5 mg prednisolone daily for 2 years (P-group; n=108) or no prednisolone (NoP-group; n=117) when they started with their first disease-modifying anti-rheumatic drug and were prospectively followed for 2 years.

RESULTS

The frequency of patients with radiographic progression after 2 years was 26% in the P-group and 39% in the NoP-group (p=0.033). Relevant interactions between treatment and rheumatoid factor (RF) (p=0.061) and between treatment and anti-cyclic citrullinated peptide 2 (anti-CCP) (p=0.096) were found. RF and anti-CCP independently predicted radiographic progression only in the NoP-group, OR (95% CI) 9.4 (2.5 to 35.2), p=0.001 and OR (95% CI) 8.7 (2.5 to 31.3), p=0.001, respectively.

CONCLUSIONS

The presence of RF and anti-CCP predicted radiographic progression in patients not treated with prednisolone but failed to predict progression in patients treated with this drug. The data suggest that early treatment with prednisolone may modulate not only inflammation but also autoimmunity-associated pathogenetic mechanisms.

TRIAL REGISTRATION NUMBER

ISRCTN20612367.

Single sST2 protein measurement predicts adverse outcomes at 1-year follow-up in patients with chronic heart failure

INTRODUCTION

sST2 protein is a new biomarker. Its prognostic value in chronic heart failure (CHF) is still unclear.

OBJECTIVES

The aim of the study was to evaluate the value of sST2 protein in patients with CHF during 1-year follow-up after hospitalization for prediction of adverse events: cardiovascular death, rehospitalization, an increase in diuretic doses, and/or worsening of the New York Heart Association functional class, defined as the composite endpoint.

PATIENTS AND METHODS

The study involved 145 consecutive patients (mean age, 62.16 ±11.25 y; men, 82.76%) with left ventricular (LV) ejection fraction of 30% or less and symptomatic CHF. We analyzed clinical and biochemical data along with the serum concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and sST2. The optimal cut-off points for significant predictors of the composite endpoint were determined using receiver operating characteristi c curves.

RESULTS

Patients with elevated levels of sST2 and NT-proBNP had more than a 4-fold higher risk of composite endpoint (odds ratio [OR], 4.033; 95%CI, 1.540-10.559) compared with patients in whom both biomarkers were below the cut-off points. The C-statistic for predicting the composite endpoint was improved when both biomarkers were incorporated into the model (C-statistic, 0.692; P = 0.0001) compared with an individual analysis for NT-proBNP (C-statistic, 0.606; P = 0.009) and sST2 (C-statistic, 0.613; P = 0.003). Moreover, after the addition of sST2 to NT-proBNP, the continuous net reclassification improvement index (OR, 0.256; 95% CI, 0.090-0.401; P = 0.007) and the integrated discrimination improvement index (OR, 0.104; 95% CI 0.011-0.221; P = 0.007) significantly improved.

CONCLUSIONS

A single measurement of sST2 levels on admission in patients with poor LV systolic function and stable CHF is useful in short-term risk stratification and, in combination with NT-proBNP, it could be more useful in identifying patients with unfavorable c ourse of CHF.

Differentiation of rheumatoid arthritis from hepatitis C-related arthropathy: case report

Chronic virus C hepatitis records high prevalence, almost 170 million people worldwide being infected. Systemic involvement is frequent and the implication of the osteoarticular system raises various problems in properly diagnosing and treating it. Rheumatoid arthritis is the most frequent type of inflammatory polyarthritis, with a prevalence of 0.8% in the general population. The rheumatoid factor recorded high values at virus C hepatitis patients (19-80%) even in the absence of articular manifestations, its sensitivity and specificity being reduced for the rheumatoid arthritis diagnosed simultaneous with virus C hepatitis. We report a case of chronic virus C hepatitis patient which, after 30 years of evolution, presents the onset of senile rheumatoid polyarthritis. The authors discuss the usefulness dosage of anti-cyclic citrullinated peptide antibodies for establishing the differential diagnosis between rheumatoid arthritis and hepatitis C-related arthropathy and the particularities of the specific treatment when there is a hepatitis C virus associated infection.

Th1 and Th2 polymorphisms in Sjögren's syndrome and rheumatoid arthritis

BACKGROUND

Sjogren's syndrome is characterized by T-cell infiltration of exocrine glands leading to parenchymal destruction and impaired glandular function. This process is orchestrated by cytokines, whose secretion can be regulated by genetic polymorphisms.

MATERIALS AND METHODS

The aim of this study was to investigate the influence of interleukin-6 -174G/C, interleukin-10 -1082G/A, tumor necrosis factor-α -308G/A, interferon-γ +874A/T gene polymorphisms in (RA) and secondary Sjögren's syndrome (sSS). A study sample that comprised of 138 Brazilian patients was divided into three groups: RA (n = 66), sSS (n = 20), and healthy controls - C (n = 52). Patients were subjected to Schirmer's test, unstimulated salivary flow rate, biopsy of minor salivary glands, and serological tests for diagnosing SS. Genomic DNA was obtained from saliva samples and submitted to genotyping. The association between genotypes/alelle frequency and SS susceptibility was tested, as well as their association with clinical features of SS.

RESULTS

Tumor necrosis factorα (TNFα)-308GA polymorphisms differed significantly between AR, SS, and C patients (P = 0.008). IL-6 overall G carriers and TNFα A carriers had a higher risk of presenting SS (P = 0.021). IL-6 polymorphism distribution was also distinctive regarding lymphocytic infiltration at the minor salivary glands (P = 0.026) and Schirmer's test (P = 0.035).

CONCLUSION

These results suggest that IL-6 -174GC and TNFα-308GA gene polymorphisms are associated with susceptibility to SS. Additionally, IL-6 polymorphism could influence lymphocytic infiltration of salivary glands and diminish lachrymal gland function.

Rheumatoid arthritis in the Women's Health Initiative: methods and baseline evaluation

Second-generation assays for anti-cyclic citrullinated peptide (anti-CCP), a highly sensitive and specific marker for rheumatoid arthritis (RA), have redefined the epidemiology of RA. In the Women's Health Initiative (WHI) RA study (2009-2011), we evaluated the prevalence of anti-CCP positivity among 15,691 (10.2% of 161,808) WHI participants aged 50-79 years who reported RA. Using stored baseline specimens, we measured serum anti-CCP, rheumatoid factor (RF), and antinuclear antibody in a defined sample of 9,988 of black, white, and Hispanic women. In a subset of women, we measured plasma cytokine levels and number of copies of the human leukocyte antigen (HLA)-DRB1 (HLA-DRB1) shared epitope in DNA by means of Luminex polymerase chain reaction typing (Luminex Corporation, Austin, Texas). We validated classification of probable clinical RA in 2 clinics as anti-CCP positivity or self-reported validated use of disease-modifying antirheumatic drugs (DMARDs). The prevalence of anti-CCP positivity was 8.1%, and the prevalence of RF positivity was approximately 16.0%. DMARD use including prednisone was reported by 1,140 (11.4%) participants (841 excluding prednisone) but by 57.5% of anti-CCP-positive women. The prevalence of 2 shared epitopes was also much higher for anti-CCP-positive women (18.2%, as opposed to only 5.5% for women with anti-CCP-negative DMARD-positive RA and 6.6% for anti-CCP-negative, RF-negative DMARD nonusers). Median cytokine levels were much higher for anti-CCP-positive/RF-positive women. Women with anti-CCP-positive RA and anti-CCP-negative RA had different characteristics with regard to HLA shared epitope, cigarette smoking, and inflammation (cytokines).

A FIM study to assess safety and exposure of inhaled single doses of AP301-A specific ENaC channel activator for the treatment of acute lung injury

AP301 is an activator of ENaC-mediated Na(+) uptake for the treatment of pulmonary permeability edema in acute respiratory distress syndrome (ARDS). The purpose of this "first-in-man" study was to examine local and systemic safety and systemic exposure of ascending single doses of AP301, when inhaled by healthy male subjects. In a double-blind, placebo-controlled study, 48 healthy male subjects were randomized to 6 ascending dose groups (single doses up to 120 mg) of 8 subjects each (3:1 randomization of AP301: placebo). Serial assessments included spirometry, exhaled nitric oxide (eNO), vital signs, ECG, safety laboratory, adverse events (AE), and blood samples for the quantification of AP301 in plasma. Descriptive statistics was applied. All 48 subjects received treatment, and completed the study as per protocol. No serious, local (e.g., hoarseness, cough, bronchospasm), or dose-limiting AEs were noted. None of the assessments indicated notable dose or time-related alterations of safety outcomes. Observed AP301 systemic exposure levels were very low, with mean Cmax values of <2.5 ng/mL in the highest dose groups. Inhaled AP301 single doses up to 120 mg were safe and well tolerated by healthy male subjects. Distribution of inhaled AP301 was largely confined to the lung, as indicated by very low AP301 systemic exposure levels.

Anti-CCP in systemic lupus erythematosus patients: a cross sectional study in Brazilian patients

Recently, it has been found that some lupus patients may have anti-cyclic citrullinated peptide antibodies (anti-CCP), although the clinical significance of such finding is not well established. Systemic lupus erythematosus (SLE) patients may have joint complaints that are very similar to those observed in rheumatoid arthritis (RA). In early stages of disease, this form of arthritis can be difficult to differentiate from RA, so it is not rare that some SLE patients are initially misdiagnosed to have this disease. This study aims to investigate the prevalence of anti-CCP in SLE patients from Southern Brazil and its association with clinical and serological profiles. One hundred nine SLE patients were studied for anti-CCP and compared with data of 156 RA patients and 100 healthy volunteers. Comparison of clinical and autoantibody profile of anti-CCP-positive and anti-CCP-negative SLE patients was done. All SLE patients positive of anti-CCP were submitted to hand and feet X-rays. Anti-CCP was positive in 15 of 109 SLE patients, and one of them had confirmed the diagnosis of rhupus. This prevalence was significantly higher than in healthy controls (p = 0.0004) and lower than in RA patients (p < 0.0001). No relationship could be found with clinical profile, including joint complaints. SLE patients with anti-CCP had higher prevalence of anti-Ro (p = 0.02) and anti-La (p = 0.004) autoantibodies, in comparison with those negative to anti-CCP. We found that 13.7% of Brazilian patients with SLE have positive anti-CCP. Patients with anti-CCP showed higher prevalence of anti-Ro and anti-La autoantibodies than those negative for anti-CCP. Only a careful and prolonged follow-up will reveal the real clinical value of these markers in each patient individually.

Predictive value of autoantibody testing for validating self-reported diagnoses of rheumatoid arthritis in the Women's Health Initiative

Rheumatoid arthritis (RA) research using large databases is limited by insufficient case validity. Of 161,808 postmenopausal women in the Women's Health Initiative, 15,691 (10.2%) reported having RA, far higher than the expected 1% population prevalence. Since chart review for confirmation of an RA diagnosis is impractical in large cohort studies, the current study (2009-2011) tested the ability of baseline serum measurements of rheumatoid factor and anti-cyclic citrullinated peptide antibodies, second-generation assay (anti-CCP2), to identify physician-validated RA among the chart-review study participants with self-reported RA (n = 286). Anti-CCP2 positivity had the highest positive predictive value (PPV) (80.0%), and rheumatoid factor positivity the lowest (44.6%). Together, use of disease-modifying antirheumatic drugs and anti-CCP2 positivity increased PPV to 100% but excluded all seronegative cases (approximately 15% of all RA cases). Case definitions inclusive of seronegative cases had PPVs between 59.6% and 63.6%. False-negative results were minimized in these test definitions, as evidenced by negative predictive values of approximately 90%. Serological measurements, particularly measurement of anti-CCP2, improved the test characteristics of RA case definitions in the Women's Health Initiative.

Long-Acting Octreotide and Prolonged-Release Lanreotide Formulations Have Different Pharmacokinetic Profiles

Single-dose pharmacokinetic (PK) profiles and multiple-dose PK modeling were compared for long-acting octreotide (20 or 60 mg) and prolonged-release lanreotide (90 or 120 mg) over 91 days; steady-state profiles were simulated. All treatments were well tolerated. Octreotide 20-mg profile showed increased concentration on day 1, lag from days 2 to 6, then prolonged plateau phase (days 11-41); 60-mg PK was dose proportional. Lanreotide 90-mg profile showed C(max) on day 1 then elimination (apparent t1/2 25.5 days); 120-mg profile was underproportional. Steady-state PK of octreotide 20 mg/28 d suggested a C(mean) of 1216 rhog/mL (range, 1065-1585) with low fluctuation index (43%). Steady-state PK of lanreotide 90 mg/28 d suggested a C(mean) of 4455 rhog/mL (range, 2499-9279) with high fluctuation index (152%). Long-acting octreotide had more predictable PK than prolonged-release lanreotide. Simulated steady-state profiles suggest long-acting octreotide could be optimized to meet individual patient needs. In contrast, prolonged-release lanreotide requires exposure constantly above the therapeutic target to enable monthly long-term therapy.

Pharmacokinetics of Micafungin in Healthy Volunteers, Volunteers With Moderate Liver Disease, and Volunteers With Renal Dysfunction

Micafungin is an antifungal agent metabolized by arylsulfatase with secondary metabolism by catechol-O-methyltransferase. The objectives of this study were to estimate the pharmacokinetic parameters and plasma protein binding of micafungin in volunteers with moderate hepatic dysfunction (n = 8), volunteers with creatinine clearance < 30 mL/min (n = 9), and matched controls (n = 8 and n = 9, respectively). Single-dose micafungin pharmacokinetics were estimated using noncompartmental techniques. There was a statistically lower area under the observed micafungin concentration-time curve (AUC) from time 0 to infinity for subjects with moderate hepatic dysfunction as compared to control subjects (97.5 +/- 19 microg.h/mL vs 125.9 +/- 26.4 microg.h/mL, P = .03), although there was no difference in micafungin weight-adjusted clearance (10.9 +/- 1.7 mL/h/kg vs 9.8 +/- 1.8 mL/h/kg, P = .2). The difference in area under the concentration-time curve may be explained by the differences in body weight between subjects and controls. Renal dysfunction did not alter micafungin pharmacokinetics.

Assessment of the Safety and Pharmacokinetics of Anidulafungin When Administered With Cyclosporine

Anidulafungin is a novel antifungal agent of the echinocandin class that is intended for the treatment of invasive fungal disease. It is likely that anidulafungin will be coadministered with cyclosporine. In vitro studies and clinical studies were performed to evaluate the effect of anidulafungin on cyclosporine metabolism and to investigate the safety and pharmacokinetics of anidulafungin when concomitantly administered with cyclosporine. The potential for anidulafungin to inhibit the metabolism of cyclosporine was evaluated by pooled human hepatic microsomal protein fractions in vitro, incubating 3H-cyclosporine with different concentrations of anidulafungin. The safety of coadministration and the effects of cyclosporine on the pharmacokinetics of anidulafungin were assessed in a multiple-dose, open-label clinical study of 12 healthy volunteers. Subjects received a 200-mg intravenous loading dose of anidulafungin, followed by a daily 100-mg intravenous maintenance dose on days 2 through 8. An oral solution of cyclosporine (Neoral oral solution; 100 mg/mL) 1.25 mg/kg was also administered to subjects twice daily on days 5 through 8. In the in vitro study, the addition of anidulafungin had no effect on cyclosporine metabolism by human hepatic microsomal protein fractions. In the clinical study, no dose-limiting toxicities or serious adverse events occurred. A small increase in anidulafungin concentrations and drug exposure (22%) was observed after 4 days of dosing with cyclosporine and was not considered to be clinically relevant. The results support the concomitant use of anidulafungin and cyclosporine without the need for dosage adjustments of either drug.

[Usefulness of magnetic resonance imaging in the diagnosis of early rheumatoid arthritis: a prospective study of 20 cases]

BACKGROUND

Diagnosing early rheumatoid arthritis is difficult and radiographic signs are often late. MRI detects erosions at an early stage and visualizes synovitis, bone edema and tenosynovitis.

AIM

To assess the value of MRI for diagnosis of early forms of rheumatoid arthritis.

METHODS

Prospective study involving 20 patients who had non erosive rheumatoid arthritis lasting for less than 2 years. MRI of the hand was performed by sequences coronal and axial T1-weighted, T2 with saturated fat signal (FatSat) FatSat and T1 with gadolinium injection.

RESULTS

The median age of patients was 52 years and sex ratio M/F of 0.05. The median disease duration was 9 months. Ten patients had antibodies Anti-Cyclic citrullinated protein positive. The MRI was abnormal in 75% of patients. This review found 36 erosions which 50% were in carpal bones, 55 joints with synovitis mainly localized midcarpal and metacarpophalangeal. Bone edema was found mainly in carpal bones. Tenosynovitis affected most frequently the flexor tendons. Seventy percent of patients without anti-Cyclic citrullinated protein had a pathological MRI.

CONCLUSION

MRI has an important role in detecting infraradiological lesions in early RA. This contributes to early diagnosis and initiation effective treatment.

Delayed treatment with tumor necrosis factor inhibitors in incomplete responders to synthetic disease-modifying anti-rheumatic drugs shows an excellent effect in patients with very early rheumatoid arthritis with poor prognosis factors

We aimed to investigate whether delayed treatment with tumor necrosis factor (TNF) inhibitors in incomplete responders to synthetic disease-modifying anti-rheumatic drugs (DMARDs) was effective among patients with very early rheumatoid arthritis (RA) with poor prognosis factors. We examined 22 patients with very early RA who were positive for anti-cyclic citrullinated peptide antibodies or IgM-rheumatoid factor. The mean disease duration at entry was 14.1 weeks. A treat-to-target strategy, aiming at simplified disease activity index (SDAI) remission, was initiated with synthetic DMARDs. SDAI remission was not achieved in 9 of the 22 patients with synthetic DMARDs alone, and TNF inhibitors were added in these patients. SDAI values in these 9 patients were further examined for the following 6 months. The TNF inhibitors (infliximab 8, etanercept 1) were added at a mean interval of 34.1 weeks after the initiation of synthetic DMARDs. SDAI remission was achieved in 4 of the 9 patients (44.4%) at 3 months and in 8 of the 9 patients (88.9%) at 6 months after the introduction of the TNF inhibitors. Radiographic damage had not progressed in these patients. Delayed treatment with TNF inhibitors is effective and tolerable for patients with very early RA with poor prognosis factors.

Laboratory findings in psoriatic arthritis

Psoriatic arthritis (PsA) has been classically defined as an inflammatory arthritis associated with psoriasis. However, in comparison with other relevant inflammatory arthropathies, in which a definite diagnosis is frequently possible only by means of laboratory investigations, in PsA true laboratory diagnostic markers are lacking. Some markers are utilised more to differentiate other diseases than to characterise PsA. For example in polyarticular PsA, which may be in some cases indistinguishable from RA, the rheumatoid factor (RF) or the more specific and recently introduced antibodies to cyclic citrullinated peptides (anti-CCP), may be useful to better identify RA. However, RF was found in 5% to 13% of patients with PsA, and anti-CCP may be observed in almost similar percentage. The determination of ESR and/or CRP is frequently disappointing in PsA, since they are both elevated in only half of the patients with PsA. However, ESR and/or CRP are included in the most utilised response criteria for RA, such as ACR and DAS, and, in addition are also considered reliable in the assessment of PsA. Furthermore, elevated levels of ESR have been proposed as one of the best predictors of damage progression and, in addition, a low ESR seems protective, while an ESR >15 mm/h is one of the factors associated with an increased mortality in PsA. The synovial fluid (SF) effusion is much higher in PsA, in comparison with other arthropathies. When available, SF analysis may offer additive information useful for the diagnosis, such as the increased number of leukocytes, which underlines the inflammatory nature of the effusion even in a patient with normal serum levels of acute phase response. We found that elevated IL-1 levels in SF of patients with early disease (<6 months), may be predictive of an evolution in polyarticular form at follow-up. This observation is in keeping with the crucial role that inflammatory cytokines play in PsA, probably related to a genetic predisposition. The recent introduction in PsA of anti-TNF-alpha agents and the demonstration of their efficacy in the management of many clinical disease expressions including peripheral arthropathy, axial involvement, enthesopathy and skin manifestations, have stimulated the research also in the field of the possible laboratory markers.

Prediction of human pharmacokinetics and tissue distribution of apicidin, a potent histone deacetylase inhibitor, by physiologically based pharmacokinetic modeling

PURPOSE

The objectives of this study were to develop physiologically based models for the pharmacokinetics (PK) and organ distribution of apicidin in rats and mice and to predict human PK in blood and organs.

METHODS

The PK of apicidin was characterized in rats and mice after i.v. bolus injection, and distribution to various tissues was determined in rats following i.v. infusions at steady state. The developed models were prospectively validated within rat and within mouse and by scaling from rat to mouse using data after multiple i.v. injections. Human PK was predicted by the physiologically based modeling using intrinsic clearance data for humans from in vitro experiments.

RESULTS

The Cl(s) predicted for human (9.8 ml/min/kg) was lower than those found in mice (116.9 ml/min/kg) and rats (61.6 ml/min/kg), and the V(ss) predicted for human (1.9 l/kg) was less than in mice (2.0 l/kg) and rats (2.5 l/kg). Consequently, the predicted t (1/2) was longer in human (2.3 h) than in mice and rats (0.4 and 0.9 h, respectively). The highest concentrations of apicidin were predicted in liver followed by adipose tissue, kidney, lung, spleen, heart, arterial blood, venous blood, small intestine, stomach, muscle, testis, and brain.

CONCLUSIONS

The developed models adequately described the PK of apicidin in rats and mice and were applied to predict human PK. These models may be useful in predicting human blood and tissue concentrations of apicidin under different exposure conditions.

Mass spectrometric and peptide chip epitope analysis on the RA33 autoantigen with sera from rheumatoid arthritis patients

As the potential of epitope chips for routine application in diagnostics relies on the careful selection of peptides, reliable epitope mapping results are of utmost interest to the medical community. Mass spectrometric epitope mapping in combination with peptide chip analysis showed that autoantibodies from patients who suffered from rheumatoid arthritis (RA) were directed against distinct surface structures on the full-length human autoantigen RA33 as well as against partial sequences. Using the combined mass spectrometric epitope extraction and peptide chip analysis approach, four sequence motifs on RA33 emerged as immuno-positive, showing that epitopes were not randomly distributed on the entire RA33 amino acid sequence. A sequential epitope motif ((245)GYGGG(249)) was determined on the C-terminal part of RA33 which matched with the Western blot patient screening results using the full-length protein and, thus, was regarded as a disease-associated epitope. Other epitope motifs were found on N-terminal partial sequences ((59)RSRGFGF(65), (111)KKLFVG(116)) and again on the C-terminal part ((266)NQQPSNYG(273)) of RA33. As recognition of these latter three motifs was also recorded by peptide chip analysis using control samples which were negative in the Western blot screening, these latter motifs were regarded as "cryptic epitopes". Knowledge of disease-associated epitopes is crucial for improving the design of a customized epitope peptide chip for RA and mass spectrometric epitope mapping pivotally assisted with selecting the most informative peptide(s) to be used for future diagnostic purposes.

Association of ultrasonographic findings of synovitis with anti-cyclic citrullinated Peptide antibodies and rheumatoid factor in patients with palindromic rheumatism during active episodes

OBJECTIVE

The purpose of this study was to investigate whether the presence of ultrasonographic findings of synovitis is associated with the presence of anti-cyclic citrullinated peptide (CCP) antibodies and rheumatoid factor (RF) in patients with palindromic rheumatism (PR) during active episodes.

METHODS

Clinically involved regions of 84 patients with PR during active episodes were examined with high-resolution ultrasonography. Serum levels of anti-CCP antibodies were determined by an enzyme-linked immunosorbent assay, and RF levels were measured by nephelometry.

RESULTS

Thirty patients (36%) had ultrasonographic findings of synovitis during active episodes. Significantly higher positive rates of anti-CCP antibodies and RF were observed in patients with PR who had ultrasonographic findings of synovitis compared with those who had no ultrasonographic findings of synovitis (26.7% versus 5.6%; odds ratio, 6.18; P < .05; and 30.0% versus 5.6%; odds ratio, 7.29; P < .01, respectively). The intraobserver and interobserver agreement for the detection of synovitis and Doppler signals by ultrasonographic assessment was excellent.

CONCLUSIONS

Ultrasonography is a reliable method for assessing the presence of synovitis in patients with PR during active episodes. The ultrasonographic findings of synovitis are associated with the presence of anti-CCP antibodies and RF in patients with PR.

TNF receptor I polymorphism is associated with persistent palindromic rheumatism

OBJECTIVES

To investigate the association between tumour necrosis factor-alpha (TNFalpha), TNF receptor superfamily member 1A (TNFRSF1A, also known as TNFRI), TNFRSF1B (TNFRII), and interleukin-1beta (IL-1beta) single nucleotide polymorphisms (SNPs) and the susceptibility to persistent palindromic rheumatism (PR).

METHODS

Fifty-six unrelated patients with persistent PR and 100 unrelated healthy controls were genotyped for TNFalpha -308G/A, -238G/A, and +488G/A, TNFRSF1A -609G/T and +36A/G, TNFRSF1B +676T/G and +1663G/A, and IL-1beta -511C/T, -31T/C, and +3954C/T using real-time polymerase chain reaction (RT-PCR).

RESULTS

The TNFRSF1A +36G allele [odds ratio (OR) = 3.94, p = 0.003, corrected p (p(c)) = 0.03] and the TNFRSF1A +36AG genotype (OR = 4.81, p = 0.002, p(c) = 0.04) were significantly associated with persistent PR. The frequency of TNFRSF1B +676T/+1663A was increased in PR patients (OR = 2.12, p = 0.01), but failed to reach statistical significance after Bonferroni correction. No correlation was observed between persistent PR and TNFalpha, TNFRSF1A -609G/T, or IL-1beta SNPs.

CONCLUSIONS

The results of this study provide evidence of an association between persistent PR and SNPs within the TNFRSF1A gene, and suggest that TNFRI is involved in the aetiopathogenesis of PR.

RGD-human serum albumin conjugates as efficient tumor targeting probes

Cyclic arginine-glycine-aspartate (RGD) peptides and their derivatives have been intensively studied as tumor targeting probes. One major drawback, however, is their short blood circulation half-lives, which greatly compromises their targeting efficacy. To address this issue, a cyclic peptide, c(RGDyK), and an organic dye (IRDye800 or Cy5.5) were covalently conjugated onto human serum albumin (HSA). The conjugates were subjected to in vitro cell staining, in vivo near-infrared fluorescence (NIRF) imaging, ex vivo NIRF imaging, and histologic studies to evaluate their feasibility as tumor imaging probes. As a control, RAD peptide was also coupled with HSA and labeled with IRDye800 for in vivo imaging. The HSA-RGD-IRDye800 exhibited integrin alpha(v)beta(3)-specific binding in cell staining experiment. In vivo NIRF imaging showed higher tumor accumulation and tumor to background contrast of HSA-RGD-IRDye800 over RGD-IRDye800. The integrin specificity of HSA-RGD-IRDye800 is confirmed by both successful inhibition of tumor uptake in the presence of c(RGDyK) and the inability to accumulate in integrin-positive tumors by RAD-HSA-IRDye800. Histologic examination revealed initial tumor vascular binding and eventually both tumor vasculature and tumor cell integrin binding in vivo. In summary, we successfully developed an RGD-based protein conjugate with prolonged circulation half-life for NIRF imaging of tumor integrin alpha(v)beta(3) expression. The success of this study may be generalizable for other peptide-based probes to be conjugated with HSA for prolonged tumor contrast and improved pharmacokinetics.

[Progress due to genetic research on rheumatoid arthritis: hype or hope?]

Thanks to progress in genetic research, various genetic factors involved in the pathogenesis of rheumatoid arthritis (RA) have been discovered.There is a difference in genetic risk factors for RA in patients with or without antibodies against cyclic citrullinated peptides. This has led to the idea that RA is not a single disease, but a heterogeneous syndrome. Currently known genetic risk factors are not suitable for prediction of the risk of individual patients developing RA, nor for early diagnosis, nor for determining the therapeutic strategy.Research into functional defects of gene products of genetic risk variants will increase the understanding of the pathogenesis of RA. This could lead to insights for the development of new specific medication.In the future, research into genetic factors correlated with the severity of RA disease progression or with the effect of antirheumatic medication is expected to yield interesting and hopefully clinically relevant results.

Isolation of aerucyclamides C and D and structure revision of microcyclamide 7806A: heterocyclic ribosomal peptides from Microcystis aeruginosa PCC 7806 and their antiparasite evaluation

Aerucyclamides C and D were isolated from the cyanobacterium Microcystis aeruginosa PCC 7806, and their structures established by NMR spectroscopy and chemical transformation and degradation. Acidic hydrolysis of aerucyclamide C (CF(3)CO(2)H, H(2)O) resulted in microcyclamide 7806A. This chemical evidence combined with spectroscopic and physical data suggest a structure revision for microcyclamide 7806A, which incorporates an O-acylated Thr ammonium residue instead of the originally proposed methyl oxazoline ring. We have prepared microcyclamide 7806B upon basic and acidic treatment of microcyclamide 7806A, which suggests that both these compounds are hydrolysis products of aerucyclamide C and that the aerucyclamides A-D are the actual metabolites produced via ribosomal peptide synthesis in M. aeruginosa PCC 7806. Antiplasmodial evaluation established submicromolar IC(50) values for aerucyclamide B against Plasmodium falciparum; low micromolar values for aerucyclamide C were found against Trypanosoma brucei rhodesiense. The compounds were selective for the parasites over a cell line of L6 rat myoblasts and are thus considered for further study as antimalarial agents.

Differential response of the rheumatoid factor and anticitrullinated protein antibodies during adalimumab treatment in patients with rheumatoid arthritis

OBJECTIVE

To investigate the effect of anti-tumor necrosis factor (TNF) treatment on rheumatoid factor (IgM-RF) and anticitrullinated protein antibodies (ACPA) and its association with treatment response and acute-phase reactants.

METHODS

In a cohort of 188 consecutive patients with rheumatoid arthritis (RA) treated with adalimumab, baseline IgM-RF and ACPA were determined by ELISA, and compared to levels after 28 weeks of treatment. ACPA were measured as antibodies to cyclic citrullinated peptide (anti-CCP). The relative change of antibody levels was correlated to the European League Against Rheumatism response criteria and to the change in acute-phase reactants [erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)].

RESULTS

The median decline in IgM-RF levels was greater than the decline in ACPA levels (31% vs 8%; p<0.001). The decrease in antibody levels was greater in the group of good responders than in the group of nonresponders [43% vs 7% for IgM-RF (p<0.0001) and 16 vs -4% for ACPA (p=0.03)]. Seventeen percent of IgM-RF-positive patients at baseline turned negative at 28 weeks; this qualitative effect was not observed for ACPA. Further, the decline in IgM-RF, but not ACPA, was associated with a decrease in CRP and ESR (p=0.004 and p=0.006, respectively).

CONCLUSION

TNF treatment directly influences IgM-RF and ACPA levels, but in those responding to treatment only. The effect on IgM-RF levels and positivity status is greater than on ACPA levels and is associated with the decline in markers of inflammation. These results further emphasize the differential role these autoantibodies may play in RA; IgM-RF as marker of inflammatory activity, and ACPA as qualitatively stable hallmark of RA.

[Usefulness of examinations of serum levels of matrix metalloproteinases 1, MMP-3, MMP-9, tissue inhibitor of metalloproteinases 1, hyaluronic acid and antibodies against cyclic citrullinated peptide in Lyme arthritis, rheumatoid arthritis and patients with arthritic complaints]

Lyme disease is a multisystem disease that can affect skin, nervous system, heart and joints. Lyme arthritis can develope in about 60% of "not treated" Lyme disease patients, 10% of patients may develope chronic arthritis. Lyme arhritis symptoms (especially chronic arthritis) is similar to rheumatoid arthritis. The purpose of this study was to establish the usefulness of examinations of serum levels of matrix metalloproteinases MMP-3, MMP-9, tissue inhibitor of metalloproteinases 1 (TIMP-1), hialuronic acid (HA) and antibodies against cyclic citrullinated peptide (anti-CCP) in Lyme arthritis, rheumatoid arthritis (RA) and patients with arthritic complaints. Plasma levels of MMP-3, HA and anti-CCP were significantly higher in RA group than in Lyme arthritis group and patients with arthritic complaints. There were no significant differences in serum levels of MMP-3, MMP-9, TIMP-1, HA, anti-CCP between Lyme arthritis patients and patients with arthritic complaints and these parameters are not usefull in differential diagnoses of Lyme arthritis.

An unexpectedly high frequency of MEFV mutations in patients with anti-citrullinated protein antibody-negative palindromic rheumatism

OBJECTIVE

To investigate whether the MEFV gene, which is involved in the regulation of the inflammatory response and has been associated with familial Mediterranean fever (FMF) and intermittent hydrarthrosis, is implicated in the pathogenesis of palindromic rheumatism (PR) and to examine its clinical presentation and its evolution in a Spanish cohort of PR patients.

METHODS

Family histories, demographic clinical data, and laboratory characteristics of 75 patients diagnosed as having PR were collected from medical records and personal interviews. The healthy control group included 325 blood bank donors. The FMF control group was made up of 84 Spanish FMF patients. Genomic DNA was isolated, and MEFV gene mutation analysis was performed by polymerase chain reaction amplification and sequence analysis.

RESULTS

Sixty-five unrelated PR patients were finally included in the study. MEFV gene mutation analysis identified 8 of these 65 patients (12.3%) as carriers of at least 1 mutated MEFV allele. Patients with MEFV mutations had higher mean age and age at disease onset, but lower mean serum levels of anti-citrullinated protein antibodies (ACPAs). No other significant differences were observed between patients with and those without mutations. The frequency of MEFV mutations in ACPA-negative PR patients was 22.2%, compared with 5.3% in ACPA-positive PR patients (P = 0.058).

CONCLUSION

This study shows a previously unreported high prevalence of mutations of the MEFV gene in patients with ACPA-negative PR. This supports the hypothesis that it might be a susceptibility gene. Our findings also support the hypothesis that the MEFV gene might participate in the pathogenesis of other undifferentiated relapsing inflammatory rheumatic disorders.