Evaluation of Toll-like Receptor 4 (TLR4) Involvement in Human Atrial Fibrillation: A Computational Study.

In the present study, we have explored the involvement of Toll-like Receptor 4 (TLR4) in atrial fibrillation (AF), by using a meta-analysis of publicly available human transcriptomic data. The meta-analysis revealed 565 upregulated and 267 downregulated differentially expressed genes associated with AF. Pathway enrichment analysis highlighted a significant overrepresentation in immune-related pathways for the upregulated genes. A significant overlap between AF differentially expressed genes and TLR4-modulated genes was also identified, suggesting the potential role of TLR4 in AF-related transcriptional changes. Additionally, the analysis of other Toll-like receptors (TLRs) revealed a significant association with TLR2 and TLR3 in AF-related gene expression patterns. The examination of MYD88 and TICAM1, genes associated with TLR4 signalling pathways, indicated a significant yet nonspecific enrichment of AF differentially expressed genes. In summary, this study offers novel insights into the molecular aspects of AF, suggesting a pathophysiological role of TLR4 and other TLRs. By targeting these specific receptors, new treatments might be designed to better manage AF, offering hope for improved outcomes in affected patients.

Sulfatide inhibits fibroblast growth, activation and oxidative stress induced by ectopic insulin.

AIM: To study the effect of sulfatide on gene expression and proliferation of human primary fibroblasts induced by insulin, insulin-like growth factor-1 and human growth hormone. MATERIALS AND METHODS: Human primary fibroblasts were exposed to 1, 3 and 30 µM of sulfatide or its precursor galactosylceramide (GalCer). Proliferation was determined by 3 H-thymidine incorporation and gene expression via microarray analysis. RESULTS: Sulfatide and GalCer reduced the growth rate of fibroblasts by 32%-82% when exposed to 0.5 nM insulin. After challenge with 120 µM of H2 O2 , sulfatide reduced membrane leakage. Fibroblast gene expression was altered by sulfatide in gene pathways associated with cell cycle/growth, transforming growth factor-ß function, and encoding of proteins involved in intracellular signalling. NFKBIA, a key control element in NF-кB regulation, was decreased 2-fold by sulfatide. CONCLUSIONS: Sulfatide strongly inhibits fibroblast growth. We therefore suggest the addition of sulfatide to injectable commercial insulin formulations, which would reduce adverse fibroblast growth and improve well-being in patients with diabetes.

Discontinuation of Infliximab Therapy in Patients with Crohn's Disease.

BACKGROUND: Whether infliximab therapy can be successfully discontinued after patients with Crohn's disease have attained sustained, clinical, biochemical, and endoscopic remission is unknown. METHODS: We conducted a multicenter, randomized, double-blind, placebo-controlled withdrawal study of infliximab in patients with Crohn's disease who were in clinical, biochemical, and endoscopic remission after standard infliximab maintenance therapy for at least 1 year. Patients were randomly assigned 1:1 to continue infliximab therapy or to receive matching placebo for 48 weeks. The primary end point was time to relapse. RESULTS: This study randomly assigned 115 patients to either the infliximab-continuation group or to the infliximab-discontinuation group. No relapses were observed among the 59 patients continuing infliximab, whereas 23 of 56 patients discontinuing infliximab experienced relapse. Time to relapse was significantly shorter among patients who discontinued infliximab than among those who continued infliximab (hazard ratio, 0.080; 95% confidence interval [CI], 0.035 to 0.186; P<0.001). At the end of the trial at week 48, relapse-free survival was 100% in the infliximab-continuation group and 51% in the infliximab-discontinuation group. The key secondary end point, time to loss of remission, was significantly shorter among patients discontinuing infliximab therapy than those continuing infliximab (hazard ratio, 0.025; 95% CI, 0.003 to 0.187; P<0.001). No unexpected adverse events were reported. CONCLUSIONS: Discontinuation of infliximab for patients with Crohn's disease receiving long-term infliximab therapy and in clinical, biochemical, and endoscopic remission leads to a considerable risk of relapse. (Funded by the Nordic Trial Alliance [NordForsk], the Medical Fund of the Danish Regions [Regionernes Medicin og Behandlingspulje], the Danish Colitis-Crohn Association, and the A.P. Moller Foundation; ClinicalTrials.gov number, NCT01817426; EudraCT number, 2012-002702-51.)

Therapeutic thresholds and mechanisms for primary non-response to infliximab in inflammatory bowel disease.

BACKGROUND: Primary non-response to infliximab (IFX) inherits a poor prognosis in inflammatory bowel disease (IBD). We explored underlying mechanisms and therapeutic thresholds in an effort to provide basis for optimizing therapy. METHODS: A prospectively followed cohort of 166 IBD patients having received standard IFX induction therapy (5 mg/kg at weeks 2, 6, and 14) had trough IFX and anti-IFX antibodies (Abs) retrospectively assessed at weeks 2 (n = 148) and 6 (n = 108). Circulating TNFα was measured in matched primary non-responders (n = 29) and responders (n = 21) at baseline and weeks 6 and 14. Clinical outcome at week 14 was supported by disease activity scores in half of patients. RESULTS: In all, 18 patients (11%) had primary non-response. Infliximab was consistently lower throughout the induction phase in non-responders as compared to responders (Week 2: IFX median 18.9 µg/mL vs. 23.3, p < .05. Week 6: 8.4 vs. 17.0, p < .05). Optimal IFX thresholds associated with response was 22.9 µg/mL at week 2 (sensitivity 51%, specificity 80%, AUCROC 0.67, p < .05) and 11.8 at week 6 (72%, 77%, 0.71, p < .05). Anti-IFX Abs occurred in 28% of primary non-responders and associated with low IFX and treatment failure (OR 13.7 [2.8-67.5], p < .01). Markers of disease activity (disease activity scores, albumin, CRP) also associated with low IFX. Circulating TNFα was higher throughout induction in non-responders with ulcerative colitis but not Crohn's disease. CONCLUSION: IBD patients with primary IFX failure generally have lower IFX trough than responders during early induction phase. Pharmacokinetic failure seems common in ulcerative colits, whereas pharmacodynamic failure appears common in Crohn's disease.

Transcriptional landscape of SARS-CoV-2 infection dismantles pathogenic pathways activated by the virus, proposes unique sex-specific differences and predicts tailored therapeutic strategies.

The emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease (COVID-19) has posed a serious threat to global health. As no specific therapeutics are yet available to control disease evolution, more in-depth understanding of the pathogenic mechanisms induced by SARS-CoV-2 will help to characterize new targets for the management of COVID-19. The present study identified a specific set of biological pathways altered in primary human lung epithelium upon SARS-CoV-2 infection, and a comparison with SARS-CoV from the 2003 pandemic was studied. The transcriptomic profiles were also exploited as possible novel therapeutic targets, and anti-signature perturbation analysis predicted potential drugs to control disease progression. Among them, Mitogen-activated protein kinase kinase (MEK), serine-threonine kinase (AKT), mammalian target of rapamycin (mTOR) and I kappa B Kinase (IKK) inhibitors emerged as candidate drugs. Finally, sex-specific differences that may underlie the higher COVID-19 mortality in men are proposed.

Personalized medicine in rheumatoid arthritis: How immunogenicity impacts use of TNF inhibitors.

Up to 40% of patients treated with tumor necrosis factor alpha inhibitors (TNFi) do not respond to therapy. Testing drug bioavailability and/or anti-drug antibody (ADAb) levels may justify dosage adjustment or switch to different drugs, enabling a personalized medicine approach. We report a multicenter cross-sectional study on different methods [ELISA and a cell based functional assay (reporter gene assay - RGA)] for drug/ADAb detection, and on the relationship between drug bioavailability and ADAb. 163 patients with rheumatoid arthritis (RA) treated with infliximab (IFX; n = 67), adalimumab (ADL; n = 49) or etanercept (ETA; n = 47) were tested for drug and ADAb levels. Furthermore, we report prospective data from additional 70 patients (59 RA and 11 juvenile idiopathic arthritis - JIA) tested for drug and ADAb levels at baseline (T0) and after 3 (T3) and 6 months (T6) of treatment with ADL or ETA only. IFX-treated patients were not included because of the increasing use of IFX biosimilars. Stringent inclusion criteria were used in order to avoid unwanted variables in both studies; none of the patients used TNFi before the study, and TNFi was used only in combination with methotrexate. Clinical response was defined according to EULAR response criteria. The two assays performed comparably in the comparison study. Accordingly, ELISA was selected for the prospective study because of its feasibility in the clinical setting. The cross-sectional study found ADAb in IFX and ADL treated groups only, that were associated with a decrease in pharmacological drug availability in the blood. Comparable results were found for the ADL-treated group in the prospective study which also showed a relationship between drug/ADAb levels and the loss of clinical response. Altogether our findings support drug and anti-drug Ab monitoring in the real-world clinical setting thus enabling individualized treatment and reducing disability in chronic inflammatory arthritis.

The cytokine network in the pathogenesis of major depressive disorder. Close to translation?

Major depressive disorder (MDD) is a common condition that afflicts the general population across a broad spectrum of ages and social backgrounds. MDD has been identified by the World Health Organization as a leading cause of disability worldwide. Approximately 30% of patients are poor responsive to standard of care (SOC) treatment and novel therapeutic approaches are warranted. Since chronic inflammation, as it is often observed in certain cancers, type 2 diabetes, psoriasis and chronic arthritis, are accompanied by depression, it has been suggested that immunoinflammatory processes may be involved in the pathogenesis of MDD. Cytokines are a group of glycoproteins secreted from lymphoid and non-lymphoid cells that orchestrate immune responses. It has been suggested that a dysregulated production of cytokines may be implicated in the pathogenesis and maintenance of MDD. On the basis of their functions, cytokines can be subdivided in pro-inflammatory and anti-inflammatory cytokines. Since abnormal blood and cerebrospinal fluid of both pro and anti-inflammatory cytokines are altered in MDD, it has been suggested that abnormal cytokine homeostasis may be implicated in the pathogenesis of MDD and possibly to induction of therapeutic resistance. We review current data that indicate that cytokines may represent a useful tool to identify MDD patients that may benefit from tailored immunotherapeutic approaches and may represent a potential tailored therapeutic target.

Pathogenic contribution of the Macrophage migration inhibitory factor family to major depressive disorder and emerging tailored therapeutic approaches.

BACKGROUND: Immunoinflammatory disorders are often accompanied by depression. Here, we review the available preclinical and clinical studies suggesting a role for the pro-inflammatory cytokine Macrophage migration inhibitory factor (MIF) and the second member of the MIF family, D-dopachrome tautomerase (D-DT; DDT), in the pathogenesis of Major Depressive Disorders (MDD). METHODS: We prepared a narrative review from a search on PubMed of studies pertaining to MDD and MIF, as for October 2019. Both humans and animal studies haves been considered. RESULTS: Preclinical data show conflicting results on the role of endogenous MIF and DDT in depression. In contrast, several human studies show that circulating MIF levels tend to increase during the course of MDD. Higher levels of inflammatory biomarkers have also been associated with poorer responses to antidepressants and the levels of MIF significantly decrease after treatment, despite this may not be necessarily associated to an improvement in psychiatric symptoms. LIMITATIONS: This is a narrative and not a systematic review of the literature on the involvement of MIF in MDD. We have highlighted studies performed in humans and in animal models, irrespective of population size and methodological approach. CONCLUSIONS: This review highlights a role of MIF, and possibly DDT, in the pathogenesis of MDD. Whilst studies in animal models are discordant, the studies in patients with MDD convergently suggest that MIF plays a role in induction and maintenance of the disease. Additional studies are also needed on DDT that often displays synergistic function with MIF and their receptors.

Pattern recognition receptor polymorphisms in early periodontitis.

BACKGROUND: Even though bacteria trigger inflammation, most of the tissue destruction in periodontitis is due to the host inflammatory response. In addition to immunological events that drive development of early periodontitis, numerous environmental factors like genetics and smoking play a role. We investigated whether the carriage of selected single nucleotide polymorphisms (SNP) of toll-like receptors (TLR), NOD-like receptors (NLR) and RIG-I-like receptors (RLR) was associated with the diagnosis of early periodontitis in a case-control study. METHODS: Adolescents with positive (n = 87) and negative (n = 73) diagnosis for periodontitis had blood samples taken. All participants were genotyped for 42 SNP in the genes encoding TLR1-10, NOD1-2, DDX58, and IFIH1 using multiplex assays. Associations between SNP and periodontitis diagnosis were tested. RESULTS: TLR1-rs5743611 showed protective effect for periodontitis (CC versus GG and GC, P = 0.01, odds ratio [OR] 0.10, 95% confidence interval [CI] 0.01-0.78). Carriage of the TLR4-rs7873784 was associated with higher odds for periodontitis (GG versus CC and GC, P = 0.05, OR 2.30, 95% CI 1.00-5.63; GG versus GC, P = 0.05, OR 2.46, 95% CI 1.01-5.99). In male participants, reduced susceptibility to periodontitis was observed in carriers of TLR7-rs3853839 (CC versus GG and CG, P = 0.02, OR 0.30, 95% CI 0.11-0.85) and TLR8-rs3764879 (CC versus GG and CG, P = 0.02, OR 0.31, 95% CI 0.12-0.82). Associations were maintained after adjustments for sex, smoking habits, and mother´s education. CONCLUSION: This study demonstrated an association between TLR1-rs5743611, TLR4-rs7873784, TLR7-rs3853839, and TLR8-rs3764879 and susceptibility to periodontitis in adolescents.

Gasotransmitters and the immune system: Mode of action and novel therapeutic targets.

Gasotransmitters are a group of gaseous molecules, with pleiotropic biological functions. These molecules include nitric oxide (NO), hydrogen sulfide (H2S), and carbon monoxide (CO). Abnormal production and metabolism of these molecules have been observed in several pathological conditions. The understanding of the role of gasotransmitters in the immune system has grown significantly in the past years, and independent studies have shed light on the effect of exogenous and endogenous gasotransmitters on immune responses. Moreover, encouraging results come from the efficacy of NO-, CO- and H2S -donors in preclinical animal models of autoimmune, acute and chronic inflammatory diseases. To date, data on the influence of gasotransmitters in immunity and immunopathology are often scattered and partial, and the scarcity of clinical trials using NO-, CO- and H2S -donors, reveals that more effort is warranted. This review focuses on the role of gasotransmitters in the immune system and covers the evidences on the possible use of gasotransmitters for the treatment of inflammatory conditions.

Biological anti-TNF drugs: immunogenicity underlying treatment failure and adverse events.

INTRODUCTION: Genetically engineered monoclonal antibodies and fusion proteins directed against cytokines or their receptors represent a breakthrough in the treatment of various chronic immune-inflammatory diseases. Areas covered: Studies show high remission rates in several diseases, but clinical practice shows a significant percentage of individuals who do not exhibit the desired response. Loss of therapeutic benefit after initial successful response is designated secondary failure. Immune-biological agents are not self-antigens and are therefore potentially immunogenic. Secondary failure is frequently caused by antibodies against immune-biologicals, known as anti-drug antibodies (ADA). ADA that neutralize circulating immune-biologicals and/or promote their clearance can reduce treatment efficacy. Furthermore, ADA can induce adverse events by diverse immunological mechanisms. This review provides a comprehensive overview of ADA in rheumatoid arthritis patients treated with anti-TNF immune-biologicals, and explores the concept of therapeutic drug monitoring (TDM) as an effective strategy to improve therapeutic management. Expert opinion: Monitoring circulating ADA and therapeutic immune-biological drugs is helpful when evaluating patients with secondary failure. However, immunological tests for ADA vary considerably regarding their ability to detect different types of ADA. Several assays are not designed to determine ADA-induced drug neutralizing capacity, and they may report clinically non-relevant data, especially if drug is present in test samples.

Cholesterol crystals enhance TLR2- and TLR4-mediated pro-inflammatory cytokine responses of monocytes to the proatherogenic oral bacterium Porphyromonas gingivalis.

Cholesterol deposits and pro-inflammatory cytokines play an essential role in the pathogenesis of atherosclerosis, a predominant cause of cardiovascular disease (CVD). Epidemiological evidence has linked periodontal disease (PD) with atherosclerotic CVD. Accordingly, viable periodontal pathogens, including Porphyromonas gingivalis, have been found in atherosclerotic plaques in humans and mice. We aimed to determine whether cholesterol crystals (CHCs) and oral bacteria synergize in the stimulation of human monocytes. Incubation of human monocytes with CHCs induced secretion of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, IL-6, and IL-8. Moreover, CHCs markedly enhanced secretion of IL-1ß by monocytes stimulated with the toll-like receptor (TLR) 4 agonist Escherichia coli lipopolysaccharide (LPS), and the TLR2 agonist Staphylococcus aureus lipoteichoic acid. Notably, CHCs also enhanced IL-1ß secretion induced by P. gingivalis LPS and IL-1ß secretion induced by whole P. gingivalis bacteria. This enhancement was abrogated by the NLRP3 inflammasome inhibitors Z-YVAD-FMK and glibenclamide. CHCs had no effect on cytokine production induced by P. gingivalis gingipains. Taken together, our findings support that CHCs, via stimulation of NLRP3 inflammasomes, act in synergy with the periodontal pathogen P. gingivalis to promote monocyte secretion of pro-atherogenic cytokines.

HIV-protease inhibitors for the treatment of cancer: Repositioning HIV protease inhibitors while developing more potent NO-hybridized derivatives?

The possible use of HIV protease inhibitors (HIV-PI) as new therapeutic option for the treatment of cancer primarily originated from their success in treating HIV-related Kaposi's sarcoma (KS). While these findings were initially attributed to immune reconstitution and better control of oncogenic viral infections, the number of reports on solid tumors, KS, lymphoma, fibrosarcoma, multiple myeloma and prostate cancer suggest other mechanisms for the anti-neoplastic activity of PIs. However, a major drawback for the possible adoption of HIV-PIs in the therapy of cancer relies on their relatively weak anticancer potency and important side effects. This has propelled several groups to generate derivatives of HIV-PIs for anticancer use, through modifications such as attachment of different moieties, ligands and transporters, including saquinavir-loaded folic acid conjugated nanoparticles and nitric oxide (NO) derivatives of HIV-PIs. In this article, we discuss the current preclinical and clinical evidences for the potential use of HIV-PIs, and of novel derivatives, such as saquinavir-NO in the treatment of cancer.

Anti-Drug Antibodies, Drug Levels, Interleukin-6 and Soluble TNF Receptors in Rheumatoid Arthritis Patients during the First 6 Months of Treatment with Adalimumab or Infliximab: A Descriptive Cohort Study.

OBJECTIVES: With the present study we wanted to explore the impact of treatment with a tumor necrosis factor-α -inhibitor (TNFi) on levels of soluble biomarkers in rheumatoid arthritis (RA) patients and to identify predictors of impaired drug levels and development of anti-TNFi antibodies (anti-TNFi Abs). METHODS: Blood samples from 26 patients with established RA were taken at baseline and following 6 months of treatment with adalimumab or infliximab. Samples were analyzed for levels of TNFi, interleukin (IL)-6, and soluble TNF-receptors 1 and -2 (sTNF-R1 and -2) and for presence of anti-TNFi Abs. Clinical and demographic data were recorded as well. RESULTS: During the initial 6 months treatment, DAS28(CRP) (Disease activity score in 28 joints using C-reactive protein) and levels of IL-6 and sTNF-R2 decreased significantly in patients without anti-TNFi Abs and in patients retaining detectable drug levels. The levels of other tested cytokines (TNF-α, TNF-ß, IL-1ra, IL-1b, IL-8, IL-10, IL-12(p70), IL-13, IL-17A, IL-17F, and IL-33) were generally below detection limits. Higher baseline levels of IL-6 associated with undetectable levels of TNFi at follow-up. Anti-TNFi Abs were associated with decreased drug levels, but no predictors for anti-TNFi Ab development could be found. CONCLUSION: The effect of treatment with TNFi on RA disease activity depends on levels of active drug, and by presence of anti-TNFi Abs. In patients who retain detectable drug levels, and in the absence of anti-TNFi Abs, clinical outcome is improved during treatment, and circulating levels of IL-6 and sTNF-R2 decrease. Baseline levels of IL-6 may predict depletion of TNFi and may identify patients at risk of treatment failure.

Optimizing Treatment with TNF Inhibitors in Inflammatory Bowel Disease by Monitoring Drug Levels and Antidrug Antibodies.

BACKGROUND: Biological tumor necrosis factor (TNF) inhibitors have revolutionized the treatment of inflammatory bowel disease and redefined treatment goals to include mucosal healing. Clinicians are faced with challenges such as inadequate responses, treatment failures, side effects, and high drug costs. The objective is to review optimization of anti-TNF therapy by use of personalized treatment strategies based on circulating drug levels and antidrug antibodies (Abs), i.e. therapeutic drug monitoring (TDM). Furthermore, to outline TDM-related pitfalls and their prevention. METHODS: Literature review. RESULTS: Circulating anti-TNF drug trough level is a marker for the pharmacokinetics (PK) of TNF inhibitors. Because of a number of factors, including antidrug antibodies, PK varies between and within patients across time leading to variable clinical outcomes. Differences in intestinal inflammatory phenotype influencing the pharmacodynamic (PD) responses to TNF inhibitors also affect treatment outcomes. As an alternative to handling anti-TNF-treated patients by empiric strategies, TDM identifies underlying PK and PD-related reasons for treatment failure and aids decision making to secure optimal clinical and economic outcomes. Although promising, evidence does not the support use of TDM to counteract treatment failure in quiescent disease. Use of TDM is challenged by methodological biases, difficulties related to differentiation between PK and PD problems, and temporal biases due to lack of chronology between changes in PK versus symptomatic and objective disease activity manifestations. Biases can be accommodated by knowledgeable interpretation of results obtained by validated assays with clinically established thresholds, and by repeated assessments over time using complimentary techniques. CONCLUSIONS: TDM-guided anti-TNF therapy at treatment failure has been brought from bench to bedside.

Circulating Cytokines and Cytokine Receptors in Infliximab Treatment Failure Due to TNF-α Independent Crohn Disease.

The inflammatory response at infliximab (IFX) treatment failure due to tumor necrosis factor (TNF)-α-independent Crohn disease activity is unknown. This is an exploratory, hypothesis-generating study based on samples collected in a clinical trial among patients failing conventional IFX dosages and treated with an intensified IFX regimen for 12 weeks. Patients with clinical response at week 12, as defined by a reduction of Crohn disease activity index by ≥70, were considered to suffer from nonimmune pharmacokinetic (PK) treatment failure (n = 18), and nonresponders had a presumed pharmacodynamic (PD) failure due to non-TNF-driven disease (n = 8). Patients failing IFX due to functional anti-IFX antibodies (n = 2) were excluded. The study population also comprised a group of 12 patients in long-term remission on IFX. A functional cell-based reporter gene assay was applied to measure IFX and anti-IFX antibodies. Circulating cytokines and cytokine receptors were assessed by enzyme-linked immunosorbent assay: granulocyte-macrophage colony-stimulating factor, interferon-γ, interleukin (IL)-1α, IL-1ß, IL-1Ra, IL-6, IL-10, IL-12p70, soluble TNF receptor (sTNF-R) 1, sTNF-R2, IL-17A, and monocyte chemotactic protein 1. The IFX levels were similar between patients with IFX failure caused by nonimmune PK or PD at treatment failure (median 1.4 vs 2.4 µg/mL; P = 0.52), during treatment intensification (8.1 vs 5.6; P = 0.85), and after 12 weeks (8.8 vs 7.7; P = 0.93), congruent with nonresponders failing IFX due to predominantly TNF-α-independent signaling pathways in their disease. Cytokine and cytokine receptor levels were comparable between patients with nonimmune PK failure and PD failure at time of manifestation of IFX failure, but with higher IL-6 and sTNF-R2 levels among IFX treatment failures as compared with patients in remission (IL-6 median 3.6 vs <3.1 pg/mL; P = 0.03; sTNF-R2 3207 vs 2547 pg/mL; P = 0.01). IL-6 and sTNF-R2 were lower after 12 weeks in nonimmune PK failures than in PD failures (<3.1 vs 4.0; P = 0.02; 3209 vs 4740; P = 0.04, respectively), and were measured at levels comparable with patients in remission. Further, trends of decreased IL-6 and sTNF-R2 levels among nonimmune PK failures during IFX intensification (P < 0.05 and P = 0.12) were observed. These observations indicate that IL-6 and sTNF-R2 are of potential relevance in driving the inflammatory response in IFX refractory Crohn disease caused by TNF-α-independent disease activity.

Phthalates Are Metabolised by Primary Thyroid Cell Cultures but Have Limited Influence on Selected Thyroid Cell Functions In Vitro.

Phthalates are plasticisers added to a wide variety of products, resulting in measurable exposure of humans. They are suspected to disrupt the thyroid axis as epidemiological studies suggest an influence on the peripheral thyroid hormone concentration. The mechanism is still unknown as only few in vitro studies within this area exist. The aim of the present study was to investigate the influence of three phthalate diesters (di-ethyl phthalate, di-n-butyl phthalate (DnBP), di-(2-ethylhexyl) phthalate (DEHP)) and two monoesters (mono-n-butyl phthalate and mono-(2-ethylhexyl) phthalate (MEHP)) on the differentiated function of primary human thyroid cell cultures. Also, the kinetics of phthalate metabolism were investigated. DEHP and its monoester, MEHP, both had an inhibitory influence on 3'-5'-cyclic adenosine monophosphate secretion from the cells, and MEHP also on thyroglobulin (Tg) secretion from the cells. Results of the lactate dehydrogenase-measurements indicated that the MEHP-mediated influence was caused by cell death. No influence on gene expression of thyroid specific genes (Tg, thyroid peroxidase, sodium iodine symporter and thyroid stimulating hormone receptor) by any of the investigated diesters could be demonstrated. All phthalate diesters were metabolised to the respective monoester, however with a fall in efficiency for high concentrations of the larger diesters DnBP and DEHP. In conclusion, human thyroid cells were able to metabolise phthalates but this phthalate-exposure did not appear to substantially influence selected functions of these cells.

Time Course and Clinical Implications of Development of Antibodies Against Adalimumab in Patients With Inflammatory Bowel Disease.

BACKGROUND: Antibodies (Abs) against adalimumab (ADL) have been associated with low ADL levels and treatment failure. AIM: To characterize the temporal characteristics of anti-ADL Ab appearance and possible disappearance, and determine the clinical significance on drug efficacy and disease course. METHODS: Cohort study including inflammatory bowel disease patients in whom anti-ADL Abs had been assessed by radioimmunoassay (RIA) and, in case of disappearance, by enzyme immunoassay, and functional reporter gene assay. RESULTS: Anti-ADL Abs were evaluated in 133 serum samples from 72 patients. Seventeen patients (24%) tested positive after median of 194 days, interquartile range of 66 to 361. The proportion with anti-ADL Abs was 22% after 1 year, and 32% from 21 months onwards. Anti-ADL Abs generally persisted at repeat assessments during continued ADL therapy (n=8). Disappearance of anti-ADL Abs during therapy (n=3) was presumably caused by methodological biases due to detection of nonfunctional nonpersistent anti-ADL Abs by RIA, or false-negative measurement at reassessment by RIA and reporter gene assay. Anti-ADL Abs appeared pharmacologically active as judged by a median ADL concentration below limit of detection versus 7.4 µg/mL in anti-ADL Ab-negative samples (P<0.0001). Anti-ADL Abs associated with loss of response (odds ratio estimated 67, P<0.0001), and shorter treatment duration (P<0.0001). CONCLUSIONS: Abs against ADL appear in approximately one fourth of inflammatory bowel disease patients with decreasing frequency over time and usually within 1 year of therapy. Anti-ADL Abs generally persist during continued ADL therapy, and are associated with elimination of drug and treatment failure. Therefore, ADL cessation should be considered when anti-ADL Abs are detected and supported by clinical observations.