Person: Cheifetz, Adam
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Cheifetz
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Cheifetz, Adam
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Publication Biologic Concentration Testing in Inflammatory Bowel Disease(Lippincott Williams & Wilkins, 2015) Vaughn, Byron P.; Sandborn, William J.; Cheifetz, AdamAbstract: Anti-TNF medications have revolutionized the care of patients with inflammatory bowel disease. However, despite an initial robust effect, loss of response is common and long-term results are disappointing. Much of this lack of durability may be due to inadequate dose optimization, and recent studies suggest a correlation between serum drug concentrations and clinical outcomes. Currently, in clinical practice, measurement of drug concentrations and antibodies to drug are typically performed only when a patient presents with active inflammatory bowel disease symptoms or during a potential immune-mediated reaction to anti-TNF (“reactive” setting). However, proactive monitoring of anti-TNF concentrations with titration to a therapeutic window (i.e., therapeutic concentration monitoring) represents a new strategy with many potential clinical benefits including prevention of immunogenicity, less need for IFX rescue therapy, and greater durability of IFX treatment. This review will cover the salient features of anti-TNF pharmacokinetics and pharmacodynamics and provide a rational approach for the use of anti-TNF concentration testing in both the reactive and proactive settings.Publication The Use of Pharmacological Prophylaxis Against Venous Thromboembolism in Hospitalised Patients With Severe Active Ulcerative Colitis(Wiley, 2014-05) Pleet, J. L.; Vaughn, Byron P.; Morris, J. A.; Moss, Alan C.; Cheifetz, AdamBackground Hospitalised patients with inflammatory bowel disease are 1.5- to 3.5-fold more likely to develop venous thromboembolism compared to controls. Clinical guidelines recommend pharmacological prophylaxis. Aim To determine the rate of pharmacological venous thromboembolism prophylaxis prescription and administration in a cohort of hospitalised patients with severe active ulcerative colitis and to assess predictors of failure to order pharmacological prophylaxis at 24 h. Methods This is a retrospective review of hospitalised patients with severe active ulcerative colitis, identified by ICD-9-CM discharge code 556.x, admitted to a single tertiary care hospital from 1 January 2005 to 31 August 2012. Adequate thromboembolism prophylaxis was defined as an order for low-dose unfractionated heparin two to three times daily, low-molecular weight heparin 40 mg daily or fondaparinux 2.5 mg daily ordered and administered for >80% of the admission. Patient related factors associated with failure to order prophylaxis at 24 h were accessed as secondary outcomes. Results Three hundred and thirty-six patients were hospitalised with severe active ulcerative colitis. Hospitalists had prescribed appropriate pharmacological prophylaxis by 48 h in only 37% of cases. Of these, nurses administered all prescribed doses in 18% of cases. Only 7% of patients (22/304, 95% CI: 5–11%) received adequate pharmacological prophylaxis for >80% of their hospitalisation. Hematochezia (P = 0.002), elevated platelets (P = 0.008), male gender coupled with younger age (P = 0.005) and admission on a biologic (P = 0.03) were associated with failure to order prophylaxis. Conclusion Hospitalised patients admitted with severe active ulcerative colitis are not receiving appropriate pharmacological venous thromboembolism prophylaxis.Publication Impact of Antibodies to Infliximab on Clinical Outcomes and Serum Infliximab Levels in Patients with Inflammatory Bowel Disease (IBD): A Meta-Analysis(Ovid Technologies (Wolters Kluwer Health), 2013-01) Nanda, Kavinderjit S.; Cheifetz, Adam; Moss, Alan C.OBJECTIVES Antibodies to infliximab (ATIs) have been associated with loss of clinical response and lower serum infliximab (IFX) levels in some studies of patients with inflammatory bowel disease (IBD). This has important implications for patient management and development of novel biologic therapies. The objective of this study was to perform a systematic review and meta-analysis of studies that reported clinical outcomes and IFX levels according to patients’ ATI status. METHODS MEDLINE, Web of Science, CINAHL, Scopus, and EMBASE were searched for eligible studies. Quality assessment was undertaken using GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria. Raw data from studies meeting inclusion criteria was pooled for meta-analysis of effect estimates. Sensitivity analysis was performed for all outcomes. Funnel plot was performed to assess for publication bias. RESULTS Thirteen studies met the inclusion criteria, and reported results in 1,378 patients with IBD. All included studies had a high risk of bias in at least one quality domain. The pooled risk ratio (RR) of loss of clinical response to IFX in patients with IBD who had ATIs was 3.2 (95 % confidence interval (CI): 2.0–4.9, P < 0.0001), when compared with patients without ATIs. This effect estimate was predominantly based on data from patients (N = 494) with Crohn’s disease (RR: 3.2, 95 % CI: 1.9–5.5, P < 0.0001). Data only from patients with ulcerative colitis (n = 86) exhibited a non-significant RR of loss of response of 2.2 (95 % CI: 0.5–9.0, P = 0.3) in those with ATIs. Heterogeneity existed between studies, in both methods of ATI detection, and clinical outcomes reported. Three studies (n = 243) reported trough serum IFX levels according to ATI status; the standardized mean difference in trough serum IFX levels between groups was −0.8 (95 % CI −1.2, −0.4, P < 0.0001). A funnel plot suggested the presence of publication bias. CONCLUSIONS The presence of ATIs is associated with a significantly higher risk of loss of clinical response to IFX and lower serum IFX levels in patients with IBD. Published studies on this topic lack uniform reporting of outcomes. High risk of bias was present in all the included studies.Publication CD73 Is a Phenotypic Marker of Effector Memory Th17 Cells in Inflammatory Bowel Disease(Wiley, 2012-10-29) Doherty, Glen; Bai, Aiping; Hanidziar, Dusan; Longhi, Maria Serena; Lawlor, Garrett; Putheti, Prabhakar; Csizmadia, Eva; Nowak, Martina; Cheifetz, Adam; Moss, Alan; Robson, SimonPurinergic signaling and associated ectonucleotidases, such as CD39 and CD73, have been implicated in the pathogenesis of inflammatory bowel disease (IBD). CD39 is known to be a Treg memory cell marker, and here we determine the phenotype and function of CD73+CD4+ T lymphocytes in patients with IBD. We describe elevated levels of CD73+CD4+ T cells in the peripheral blood and intestinal lamina propria of patients with active IBD. The functional phenotype of these CD73+CD4+ T cells was further determined by gene expression, ecto-enzymatic activity, and suppressive assays. Increased numbers of CD73+CD4+ T cells in the periphery and lamina propria were noted during active inflammation, which returned to baseline levels following anti-TNF treatment. Peripheral CD73+CD4+ T cells predominantly expressed CD45RO, and were enriched with IL-17A+ cells. The CD73+CD4+ cell population expressed higher levels of RORC, IL-17A, and TNF, and lower levels of FOXP3 and/or CD25, than CD73−CD4+ T cells. Expression of CD73 by peripheral CD4+ T cells was increased by TNF, and decreased by an anti-TNF monoclonal antibody (infliximab). In vitro, these peripheral CD73+CD4+ T cells did not suppress proliferation of CD25− effector cells, and expressed higher levels of pro-inflammatory markers. We conclude that the CD73+CD4+ T-cell population in patients with active IBD are enriched with cells with a T-helper type 17 phenotype, and could be used to monitor disease activity during treatment.Publication Predictors of Endoscopic Inflammation in Patients with Ulcerative Colitis in Clinical Remission(Oxford University Press (OUP), 2013-04-01) Rosenberg, Laura; Lawlor, Garreth O.; Zenlea, Talia; Goldsmith, Jeffrey; Gifford, Anne; Falchuk, Kenneth; Wolf, Jacqueline; Cheifetz, Adam; Robson, Simon; Moss, Alan C.Objectives Patients with ulcerative colitis (UC) who are in clinical remission may still have underlying endoscopic inflammation, which is associated with inferior clinical outcomes. The goal of this study was to determine the prevalence of, and factors associated with, active endoscopic disease in patients with UC who are in clinical remission. Design Prospective observational study in a single center. Patients with UC in clinical remission (by SCCAI) were enrolled prospectively at time of surveillance colonoscopy. Disease phenotype, endoscopic activity (Mayo sub-score) and histological score (Geboes) were recorded, and blood was drawn for peripheral blood biomarkers. Results 149 patients in clinical remission were prospectively enrolled in this cohort; 81% had been in clinical remission for > 6 months, and 86% were currently prescribed maintenance medications. At endoscopy 45% of patients in clinical remission had any endoscopic inflammation (Mayo endoscopy sub-score >0) and 13% had scores >1. In a multivariate model, variables independently associated with a Mayo endoscopic score >1 were remission for < 6 months (p=.001), WBC (p=0.01) and CRP (p=0.009). A model combining these three variables had a sensitivity of 94% and a specificity of 73% for predicting moderate-severe endoscopic activity in patients in clinical remission (AUC 0.86). In an unselected sub-group of patients who had peripheral blood mononuclear cell mRNA profiling, GATA3 mRNA levels were significantly higher in patients with endoscopic activity. Conclusions Duration of clinical remission, WCC and CRP can predict the probability of on-going endoscopic activity despite clinical remission in patients with UC. These parameters could be used to identify patients who require intensification of treatment to achieve mucosal healing.Publication Lectin-Reactive Anti-α-Gal in Patients with Crohnʼs Disease: Correlation with Clinical Phenotypes(Oxford University Press (OUP), 2013-12-01) Safaie, Parham; Ham, Maggie; Kuang, Peter; Mehta, Anand S.; Wang, Mengjun; Cheifetz, Adam; Robson, Simon; Lau, Daryl; Block, Timothy M.; Moss, Alan C.Background Patients with inflammatory bowel disease have higher proportions of immunoglobulin G (IgG) antibodies lacking N-galactose, also called agalactosyl IgG, in their serum. Such agalactosyl IgGs have been associated with disease activity and the immunogenicity of biologics. The aim was to describe the relationship between circulating levels of a subset of agalactosyl IgGs (anti-α-Gal) and Crohn’s disease (CD) phenotypes. Methods Prospectively collected serum samples of a well-characterized cohort of patients with inflammatory bowel disease and controls were used. Serum anti-α-Gal levels were measured by a high-affinity enzyme-linked immunosorbent assay and referenced to a standard control. Results Serum samples from 167 subjects were tested; 62 with CD, 76 with ulcerative colitis, and 29 controls. Agalactosyl anti-α-Gal levels were significantly higher in active CD than in active ulcerative colitis (P = 0.0043) or healthy controls (P < 0.0001). Among patients with CD, agalactosyl anti-α-Gal levels were significantly higher in those with a history of arthritis, than those without (P = 0.0002), but lower in those taking immunomodulators (P = 0.03). There was no correlation between agalactosyl anti-α-Gal levels and indices of Crohn’s severity, including C-reactive protein levels or Harvey– Bradshaw index. Patients who were primary or secondary nonresponders to infliximab had similar agalactosyl anti-α-Gal levels to clinical responders. Conclusions Patients with CD have greater amounts of agalactosylated anti-α-Gal antibodies in their serum, particularly in those with associated joint disease. This increase seems to be independent of indices of disease activity, but is influenced by immunomodulator use.Publication Comparative Cost-Effectiveness of Strategies to Prevent Postoperative Clinical Recurrence of Crohnʼs Disease(Oxford University Press (OUP), 2012-09-01) Doherty, Glen; Miksad, Rebecca A.; Cheifetz, Adam; Moss, Alan C.Background A number of treatments have been shown to reduce the risk of postoperative recurrence of Crohn's disease (CD). The optimal strategy is unknown. The aim was to evaluate the comparative cost-effectiveness of postoperative strategies to prevent clinical recurrence of CD. Methods Three prophylactic strategies were compared to “no prophylaxis”; mesalamine, azathioprine (AZA) / 6-mercaptopurine (6-MP), and infliximab. The probability of clinical recurrence, endoscopic recurrence, and therapy discontinuation due to adverse drug reactions (ADRs) were extracted from randomized controlled trials (RCTs). Quality-of-life scores and treatment costs were derived from published data. The primary model evaluated quality-adjusted life years (QALYs) and cost-effectiveness at 1 year after surgery. Sensitivity analysis assessed the impact of a range of recurrence rates on cost-effectiveness. An exploratory analysis evaluated cost-effectiveness outcomes 5 years after surgery. Results A strategy of “no prophylaxis” was the least expensive one at 1 and 5 years after surgery. Compared to this approach, AZA/6-MP had the most favorable incremental cost-effectiveness ratio (ICER) (USD 299,188/QALY gained), and yielded the highest net health benefits of the medication strategies at 1 year. Sensitivity analysis determined that the ICER of AZA/6-MP was preferable to mesalamine up to a recurrence rate of 52%, but mesalamine dominated at higher rates. In the 5-year exploratory analysis, mesalamine had the most favorable ICER over 5 years (USD 244,177/QALY gained). Conclusions Compared to no prophylactic treatment, AZA/6-MP has the most favorable ICER in the prevention of clinical recurrence of postoperative CD up to 1 year. At 5 years, mesalamine had the most favorable ICER in this model.Publication Vitamin D Levels in Adults with Crohnʼs Disease Are Responsive to Disease Activity and Treatment(Oxford University Press (OUP), 2014-05) Brigham, Maggie; Longhi, Maria Serena; Lahiff, Conor; Cheifetz, Adam; Robson, Simon; Moss, Alan C.Background: Vitamin D deficiency is common in patients with Crohn’s disease (CD), although whether this impairs immune responsiveness, and is related to disease activity per se, remains unclear. We sought to investigate vitamin D pathways in patients with CD according to measures of inflammation and immune response. Methods: Prospectively collected samples of a well-characterized cohort of patients with CD were used to measure serum 25(OH)-vitamin D levels by enzyme-linked immunoassay. Related gene expression was determined by polymerase chain reaction in T cells. The effect of vitamin D on the proliferation of isolated CD4+ cells was determined. Results: Patients with active CD had lower serum vitamin D levels than those in clinical remission; this measurement was independent of season or reported use of vitamin D supplements. Harvey–Bradshaw Index scores, but not C-reactive protein, correlated with serum vitamin D levels. Gene expression of the vitamin D receptor was higher in peripheral blood T cells from patients with active disease than in those in remission. The proportion of CD25hi CD4+ cells from patients with CD increased in the presence of vitamin D. After treatment with infliximab, significant increases in serum vitamin D levels were noted in patients. Conclusions: Low vitamin D levels are associated with disease activity in CD and increase after infliximab treatment.Publication CD39 and CD161 Modulate Th17 Responses in Crohn's Disease(The American Association of Immunologists, 2014-08-29) Bai, Aiping; Moss, Alan; Kokkotou, Efi; Usheva, Anny; Sun, Xiaofeng; Cheifetz, Adam; Zheng, Yi; Longhi, Maria Serena; Gao, Wenda; Wu, Yan; Robson, SimonCD39 (ENTPD1) is expressed by subsets of pathogenic human CD4+ T cells, such as T helper type 17 (Th17) cells. These Th17 cells are considered important in intestinal inflammation, such as seen in Crohn’s disease. Recently, CD161 (NKR-P1A) has been shown to be a phenotypic marker of human Th17 cells. In this study, we report that co-expression of CD161 and CD39 not only identifies these cells but also promotes Th17 generation. We note that human CD4+CD39+CD161+ T cells can be induced under stimulatory conditions that promote Th17 in vitro. Furthermore, CD4+CD39+CD161+ cells purified from blood and intestinal tissues, from both healthy controls and patients with Crohn’s disease, are of the Th17 phenotype and exhibit pro-inflammatory functions. CD39 is co-expressed with CD161, and this association augments acid sphingomyelinase (ASM) activity upon stimulation of CD4+ T cells. These pathways regulate mTOR and STAT3 signaling to drive the Th17 phenotype. Inhibition of ASM activity by pharmacological blockers or knockdown of ASM abrogates STAT3 signaling, thereby limiting IL-17 production in CD4+ T cells obtained from both controls and patients with active Crohn’s disease. Increased levels of CD39+CD161+ CD4+ T cells in blood or lamina propria are noted in patients with Crohn’s disease; and levels directly correlate with clinical disease activity. Hence, co-expression of CD39 and CD161 by CD4+ T cells might serve as a biomarker to monitor Th17 responsiveness. Collectively, CD39 and CD161 modulate human Th17 responses in Crohn's disease through alterations in purinergic nucleotide-mediated responses and ASM catalytic bioactivity, respectively.Publication Characterization of Human CD39+ Th17 Cells with Suppressor Activity and Modulation in Inflammatory Bowel Disease(Public Library of Science, 2014) Longhi, Maria Serena; Moss, Alan; Bai, A; Wu, Yan; Huang, Huang; Cheifetz, Adam; Quintana, Francisco; Robson, SimonInduced regulatory T-cells (iT-reg) and T helper type 17 (Th17) in the mouse share common CD4 progenitor cells and exhibit overlapping phenotypic and functional features. Here, we show that human Th17 cells endowed with suppressor activity (supTh17) can be derived following exposure of iT-reg populations to Th17 polarizing conditions. In contrast to “pathogenic” Th17, supTh17 display immune suppressive function and express high levels of CD39, an ectonucleotidase that catalyzes the conversion of pro-inflammatory extracellular nucleotides ultimately generating nucleosides. Accordingly, supTh17 exhibit nucleoside triphosphate diphosphohydrolase activity, as demonstrated by the efficient generation of extracellular AMP, adenosine and other purine derivatives. In addition supTh17 cells are resistant to the effects of adenosine as result of the low expression of the A2A receptor and accelerated adenosine catalysis by adenosine deaminase (ADA). These supTh17 can be detected in the blood and in the lamina propria of healthy subjects. However, these supTh17 cells are diminished in patients with Crohn’s disease. In summary, we describe a human Th17 subpopulation with suppressor activity, which expresses high levels of CD39 and consequently produces extracellular adenosine. As these uniquely suppressive CD39+ Th17 cells are decreased in patients with inflammatory bowel disease, our findings might have implications for the development of novel anti-inflammatory therapeutic approaches in these and potentially other immune disorders.