Target Occupancy and Functional Inhibition of JAK3 and TEC Family Kinases by Ritlecitinib in Healthy Adults: An Open-Label, Phase 1 Study

Ritlecitinib is a small molecule in clinical development that covalently and irreversibly inhibits Janus kinase 3 (JAK3) and the TEC family of kinases (BTK, BMX, ITK, TXK, and TEC). This phase 1, open-label, parallel-group study assessed target occupancy and functional effects of ritlecitinib on JAK3 and TEC family kinases in healthy participants aged 18-60 years who received 50 or 200 mg single doses of ritlecitinib on day 1. Blood samples to assess ritlecitinib pharmacokinetics, target occupancy, and pharmacodynamics were collected over 48 hours. Target occupancy was assessed using mass spectroscopy. Functional inhibition of JAK3-dependent signaling was measured by the inhibition of the phosphorylation of its downstream target signal transducer and activator of transcription 5 (pSTAT5), following activation by interleukin 15 (IL-15). The functional inhibition of Bruton's tyrosine kinase (BTK)-dependent signaling was measured by the reduction in the upregulation of cluster of differentiation 69 (CD69), an early marker of B-cell activation, following treatment with anti-immunoglobulin D. Eight participants received one 50 mg ritlecitinib dose and 8 participants received one 200 mg dose. Ritlecitinib plasma exposure increased in an approximately dose-proportional manner from 50 to 200 mg. The maximal median JAK3 target occupancy was 72% for 50 mg and 64% for 200 mg. Ritlecitinib 50 mg had >94% maximal target occupancy of all TEC kinases, except BMX (87%), and 200 mg had >97% for all TEC kinases. For BTK and TEC, ritlecitinib maintained high target occupancy throughout a period of 48 hours. Ritlecitinib reduced pSTAT5 levels following IL-15- and BTK-dependent signaling in a dose-dependent manner. These target occupancy and functional assays demonstrate the dual inhibition of the JAK3- and BTK-dependent pathways by ritlecitinib. Further studies are needed to understand the contribution to clinical effects of inhibiting these pathways.

Application of clinical and molecular profiling data to improve patient outcomes in psoriatic arthritis

Achieving a good outcome for a person with Psoriatic Arthritis (PsA) is made difficult by late diagnosis, heterogenous clinical disease expression and in many cases, failure to adequately suppress inflammatory disease features. Single-centre studies have certainly contributed to our understanding of disease pathogenesis, but to adequately address the major areas of unmet need, multi-partner, collaborative research programmes are now required. HIPPOCRATES is a 5-year, Innovative Medicines Initiative (IMI) programme which includes 17 European academic centres experienced in PsA research, 5 pharmaceutical industry partners, 3 small-/medium-sized industry partners and 2 patient-representative organizations. In this review, the ambitious programme of work to be undertaken by HIPPOCRATES is outlined and common approaches and challenges are identified. It is expected that, when completed, the results will ultimately allow for changes in the approaches to diagnosing, managing and treating PsA allowing for better short-term and long-term outcomes.

Decreased Ventral Tegmental Area CB1R Signaling Reduces Sign Tracking and Shifts Cue-Outcome Dynamics in Rat Nucleus Accumbens

Sign-tracking (ST) rats show enhanced cue sensitivity before drug experience that predicts greater discrete cue-induced drug seeking compared with goal-tracking or intermediate rats. Cue-evoked dopamine in the nucleus accumbens (NAc) is a neurobiological signature of sign-tracking behaviors. Here, we examine a critical regulator of the dopamine system, endocannabinoids, which bind the cannabinoid receptor-1 (CB1R) in the ventral tegmental area (VTA) to control cue-evoked striatal dopamine levels. We use cell type-specific optogenetics, intra-VTA pharmacology, and fiber photometry to test the hypothesis that VTA CB1R receptor signaling regulates NAc dopamine levels to control sign tracking. We trained male and female rats in a Pavlovian lever autoshaping (PLA) task to determine their tracking groups before testing the effect of VTA → NAc dopamine inhibition. We found that this circuit is critical for mediating the vigor of the ST response. Upstream of this circuit, intra-VTA infusions of rimonabant, a CB1R inverse agonist, during PLA decrease lever and increase food cup approach in sign-trackers. Using fiber photometry to measure fluorescent signals from a dopamine sensor, GRABDA (AAV9-hSyn-DA2m), we tested the effects of intra-VTA rimonabant on NAc dopamine dynamics during autoshaping in female rats. We found that intra-VTA rimonabant decreased sign-tracking behaviors, which was associated with increases in NAc shell, but not core, dopamine levels during reward delivery [unconditioned stimulus (US)]. Our results suggest that CB1R signaling in the VTA influences the balance between the conditioned stimulus-evoked and US-evoked dopamine responses in the NAc shell and biases behavioral responding to cues in sign-tracking rats.SIGNIFICANCE STATEMENT Substance use disorder (SUD) is a chronically relapsing psychological disorder that affects a subset of individuals who engage in drug use. Recent research suggests that there are individual behavioral and neurobiological differences before drug experience that predict SUD and relapse vulnerabilities. Here, we investigate how midbrain endocannabinoids regulate a brain pathway that is exclusively involved in driving cue-motivated behaviors of sign-tracking rats. This work contributes to our mechanistic understanding of individual vulnerabilities to cue-triggered natural reward seeking that have relevance for drug-motivated behaviors.

Dopamine in the dorsal bed nucleus of stria terminalis signals Pavlovian sign-tracking and reward violations

Midbrain and striatal dopamine signals have been extremely well characterized over the past several decades, yet novel dopamine signals and functions in reward learning and motivation continue to emerge. A similar characterization of real-time sub-second dopamine signals in areas outside of the striatum has been limited. Recent advances in fluorescent sensor technology and fiber photometry permit the measurement of dopamine binding correlates, which can divulge basic functions of dopamine signaling in non-striatal dopamine terminal regions, like the dorsal bed nucleus of the stria terminalis (dBNST). Here, we record GRAB_DA signals in the dBNST during a Pavlovian lever autoshaping task. We observe greater Pavlovian cue-evoked dBNST GRAB_DA signals in sign-tracking (ST) compared to goal-tracking/intermediate (GT/INT) rats and the magnitude of cue-evoked dBNST GRAB_DA signals decreases immediately following reinforcer-specific satiety. When we deliver unexpected rewards or omit expected rewards, we find that dBNST dopamine signals encode bidirectional reward prediction errors in GT/INT rats, but only positive prediction errors in ST rats. Since sign- and goal-tracking approach strategies are associated with distinct drug relapse vulnerabilities, we examined the effects of experimenter-administered fentanyl on dBNST dopamine associative encoding. Systemic fentanyl injections do not disrupt cue discrimination but generally potentiate dBNST dopamine signals. These results reveal multiple dBNST dopamine correlates of learning and motivation that depend on the Pavlovian approach strategy employed.

Novel use of ultrasound-guided transgluteal sciatic nerve block to treat severe herpes zoster pain along the S1 dermatome

Patients presenting with herpes zoster (HZ) to emergency departments (EDs) across the United States represent a significant number of visits and have pain that is difficult to manage, sometimes even requiring opioid medications for adequate analgesia. Ultrasound-guided nerve blocks (UGNBs) are becoming more integrated into the ED physician's tool box for a multimodal approach to analgesia in various indications. Here we describe a novel use of the transgluteal sciatic UGNB for treatment of HZ pain along the S1 dermatome. A 48-year-old woman presented to the ED with right-sided leg pain associated with a HZ rash. After initially failing non-opioid pain management, the ED physician performed a transgluteal sciatic UGNB for our patient, leading to successful complete resolution of her pain, with no adverse effects reported. Our case highlights the potential role of using the transgluteal sciatic UGNB for analgesia related to HZ-related pain, as well as its potential opioid-sparing benefits. Although UGNBs require a baseline understanding of ultrasound technique for procedural guidance, this skillset has recently been incorporated as core competency within emergency medicine training in the United States. UGNBs should therefore be considered in the multimodal analgesic armamentarium for the ED treatment of HZ pain.

Efficacy and Safety of Tyrosine Kinase 2/Janus Kinase 1 Inhibitor Brepocitinib for Active Psoriatic Arthritis: A Phase IIb Randomized Controlled Trial

OBJECTIVE

Brepocitinib is a tyrosine kinase 2/Janus kinase 1 inhibitor in development for treatment of several immunological diseases. Efficacy and safety of oral brepocitinib were assessed in participants with moderately-to-severely active psoriatic arthritis (PsA) for up to 52 weeks.

METHODS

This placebo-controlled, dose-ranging, phase IIb study randomized participants to brepocitinib 10 mg once daily (QD), 30 mg QD, 60 mg QD, or placebo, advancing to brepocitinib 30 or 60 mg QD at week 16. The primary endpoint was American College of Rheumatology (ACR)20 response rate at week 16. Secondary endpoints included response rates of ACR50/70, 75% and 90% improvement in Psoriasis Area and Severity Index (PASI75/90), and Minimal Disease Activity (MDA) at weeks 16 and 52. Adverse events (AEs) were monitored throughout.

RESULTS

Overall, 218 participants were randomized and treated. At week 16, brepocitinib 30 and 60 mg QD groups had significantly greater ACR20 response rates (66.7% [P = 0.0197] and 74.6% [P = 0.0006], respectively), versus placebo (43.3%) and significantly higher ACR50/70, PASI75/90, and MDA response rates. Response rates were maintained or improved through week 52. AEs were mostly mild/moderate; serious AEs (15) in 12 (5.5%) participants included infections in 6 (2.8%) in brepocitinib 30 and 60 mg QD groups. No major adverse cardiovascular events or deaths occurred.

CONCLUSION

Brepocitinib 30 and 60 mg QD were superior to placebo at reducing signs and symptoms of PsA. Brepocitinib was generally well tolerated throughout the 52-week study with a safety profile consistent with other brepocitinib clinical trials.

Biomarkers to predict risk of venous thromboembolism in patients with rheumatoid arthritis receiving tofacitinib or tumour necrosis factor inhibitors

OBJECTIVE

In the ORAL (Oral Rheumatoid Arthritis triaL) Surveillance study of patients with rheumatoid arthritis aged ≥50 years with ≥1 additional cardiovascular risk factor, incidence of pulmonary embolism was higher with tofacitinib 10 mg two times per day than with tumour necrosis factor inhibitors (TNFi). This exploratory post hoc analysis examined whether biomarkers explained the associations of tofacitinib versus TNFi with venous thromboembolism (VTE).

METHODS

ORAL Surveillance was a prospective, open-label, event-driven, non-inferiority, postauthorisation safety study. Patients were randomised 1:1:1 to receive tofacitinib 5 mg or 10 mg two times per day or a TNFi. For this analysis, 294 soluble, proteomic, genetic and antibody biomarkers (of which 79 had a known role in inflammation, coagulation, vascular biology or Janus kinase signalling) were quantified in serum collected at baseline, month 12 and study end.

RESULTS

Overall, 4362 patients were randomised and treated. The exploratory biomarker data set included 285 patients (57 VTE cases; 228 matched controls). D-dimer was quantified in 3732 patients (54 VTE cases; 3678 controls). No biomarker demonstrated a clear mechanistic association with the increased risk of VTE for tofacitinib versus TNFi. Month 12 D-dimer levels were positively associated with risk of a subsequent VTE within the tofacitinib 5 mg and 10 mg two times per day arms.

CONCLUSIONS

Overall, this post hoc analysis did not identify biomarkers that explained the increased VTE risk for tofacitinib versus TNFi. Individual VTE risk should be considered when making decisions about initiation or maintenance of tofacitinib treatment.

TRIAL REGISTRATION NUMBER

NCT02092467; ClinicalTrials.gov.

Point-of-Care Ultrasound Diagnosis of Tetralogy of Fallot Causing Cyanosis: A Case Report

INTRODUCTION

Tetralogy of Fallot (TOF) is a congenital heart defect with characteristic features leading to unique physical exam and ultrasound findings. In settings where there is limited prenatal screening, TOF can present with cyanosis at any time from the neonatal period to adulthood depending on the degree of obstruction of the right ventricular outflow tract.

CASE REPORT

This case describes a pediatric patient who presented with undifferentiated dyspnea and cyanosis, for whom point-of-care ultrasound (POCUS) supported the diagnosis of TOF. We highlight the important role POCUS can play in a setting with limited access to formal echocardiography or consultative pediatric cardiology services.

CONCLUSION

This report highlights the utility of POCUS as an inflection point in the diagnostic and management pathway of this patient, which is particularly important when working in a limited-resource or rural setting.

Investigating discriminative stimulus modulation of opioid seeking after conflict-induced abstinence in sign- and goal-tracking rats

RATIONALE

Discriminative stimuli (DS) are cues that predict reward availability. DS are resistant to extinction and motivate drug seeking even after long periods of abstinence. Previous studies have demonstrated that sign-tracking (ST) and goal-tracking (GT) differences in Pavlovian approach predict distinct cue-modulated vulnerabilities to cocaine reinstatement. GT rats show heightened reinstatement to contextual and DS, while ST rats show heightened reinstatement to discrete stimuli. Here we examine whether DS modulate reinstatement after electric barrier-induced abstinence and whether tracking-related relapse vulnerabilities generalize to opioid relapse.

OBJECTIVES

We examine whether DS-modulated reinstatement to fentanyl seeking persists in the presence of reduced adverse consequences after electric barrier-induced abstinence. We also examine whether tracking differences predict the magnitude of DS-modulated reinstatement of fentanyl seeking after electric barrier-induced abstinence.

METHODS

We used Pavlovian lever autoshaping (PLA) training to determine sign-, goal-, and intermediate tracking groups in male and female Sprague Dawley rats. We then trained rats in a DS model of intermittent fentanyl self-administration, and extinguished drug seeking by imposing an electric barrier of increasing intensity. We then measured the level of DS-modulated reinstatement in the presence of a reduced electric barrier intensity.

RESULTS

We report that DS strongly modulate fentanyl seeking after electric barrier-induced abstinence. DS-modulation of fentanyl acquisition, electric barrier-induced abstinence, and reinstatement was similar for sign- and goal-tracking groups.

CONCLUSIONS

Discriminative stimuli powerfully motivate opioid seeking, despite continued aversive consequences. Pavlovian approach differences do not predict the level of DS-modulated reinstatement to fentanyl seeking after conflict-induced abstinence.

Corrigendum: Role of BNST CRFR1 Receptors in Incubation of Fentanyl Seeking

[This corrects the article DOI: 10.3389/fnbeh.2020.00153.].

Role of BNST CRFR1 Receptors in Incubation of Fentanyl Seeking

The time-dependent increase in cue-triggered opioid seeking, termed “incubation of opioid craving,” is modeled in rodents by examining responding for opioid-associated cues after a period of forced abstinence. With opioid drugs, withdrawal symptoms may heighten cue reactivity by recruiting brain systems involved in both reward seeking and stress responses. Corticotropin releasing factor (CRF) in the bed nucleus of the stria terminalis (BNST) is a critical driver of stress-induced relapse to drug seeking. Here, we sought to determine whether BNST CRF receptor 1 (CRFR1) signaling drives incubation of opioid craving in opioid dependent and non-dependent rats. First, we tested whether BNST CRFR1 signaling drives incubation of opioid craving in rats with short-access fentanyl self-administration experience (2.5 μg/kg/infusion, 3 h/day for 10 days). On Day 1 of forced abstinence, we gave bilateral intra-BNST vehicle injections to all rats and measured lever responding for opioid cues in the absence of fentanyl infusions. On Day 30 of forced abstinence, we gave an identical test after bilateral intra-BNST injections of vehicle or CRFR1 receptor antagonist, R121919 (1 μg/0.3 μL/hemisphere). Vehicle treated rats showed greater responding for opioid associated cues on Day 30 relative to Day 1, and this incubation effect was prevented by intra-BNST R121919 on Day 30. Next, we incorporated an opioid-dependence procedure to investigate whether BNST CRFR1 signaling drives opioid cue-reactivity to a greater extent in opioid-dependent relative to non-dependent rats. We trained rats to self-administer fentanyl for 5 days before initiating the dependence phase and resuming daily fentanyl self-administration sessions for 10 days. We gave intra-BNST R121919 or vehicle injections before testing during acute (Day 5) or protracted (Day 30) withdrawal. During acute withdrawal, antagonizing BNST CRFR1 decreased the number of press bouts without affecting bout size or duration. These patterns of responding with R121919 treatment resulted in less fentanyl-associated conditioned reinforcement during test. Together, these findings suggest a role for BNST CRFR1 signaling in driving cue-reinforced opioid seeking after periods of forced abstinence.

A Novel Multimodal Approach to Point-of-Care Ultrasound Education in Low-Resource Settings

Point-of-care ultrasound (POCUS) enables physicians to make critical diagnosis and treatment decisions at the bedside. However, access to and expertise with this technology remain limited in Peru. Establishing longitudinal POCUS educational curriculums in remote, low-resource settings can be challenging due to geographical distances, encumbering the ability to provide ongoing hands-on support. Previously described educational interventions have focused on training individual users on clinical applications of POCUS, rather than training physicians how to teach POCUS, thereby limiting scalability and sustainable impact. We therefore describe our experiences establishing the first ultrasound fellowship curriculum in Peru, which incorporates tele-ultrasonography to circumvent traditional geographical barriers.

Janus kinase inhibitors for the treatment of rheumatoid arthritis demonstrate similar profiles of in vitro cytokine receptor inhibition

Janus kinase (JAK) inhibitors have emerged as an effective class of therapies for various inflammatory diseases such as rheumatoid arthritis (RA). JAK inhibitors function intracellularly by modulating the catalytic activity of JAKs and disrupting the receptor-mediated signaling of multiple cytokines and growth factors, including those with pro-inflammatory activity. Understanding the inhibition profiles of different JAK inhibitors, based on the associated cytokine receptors and downstream inflammatory pathways affected, is important to identify the potential mechanisms for observed differences in efficacy and safety. This study applied an integrated modeling approach, using in vitro whole blood cytokine inhibition potencies and plasma pharmacokinetics, to determine JAK-dependent cytokine receptor inhibition profiles, in the context of doses estimated to provide a similar clinical response in RA clinical trials. The calculated profiles of cytokine receptor inhibition for the JAK inhibitors tofacitinib, baricitinib, upadacitinib, and filgotinib and its metabolite, were generally similar when clinically efficacious doses for RA were considered. Only minor numerical differences in percentage cytokine receptor inhibition were observed, suggesting limited differentiation of these inhibitors based on JAK pharmacology, with each showing a differential selectivity for JAK1 heterodimer inhibition. Nevertheless, only robust clinical testing involving head-to-head studies will ultimately determine whether there are clinically meaningful differences between these JAK inhibitors. Furthermore, ongoing and future research into inhibitors with alternative JAK selectivity remains of clinical importance. Thus, all JAK inhibitors should be characterized via thorough preclinical, metabolic and pharmacological evaluation, adequate long-term clinical data, and when available, real-world experience.

Speeding up the study of diluted dipolar systems

We study the regimes of a diluted dipolar system through Monte Carlo numerical simulations in the NVT ensemble. To accelerate the dynamics, several approximations and speed-up algorithms are proposed and tested. In particular, it turns out that "cluster move Monte Carlo" algorithm speeds-up to two decades faster than the traditional Monte Carlo, depending on temperature and density. We find simple-fluid, chain-fluid, ring-fluid, gel, and antiparallel columnar regimes, which are studied and characterized through positional, orientational, and thermodynamical observables.

Effects of International Law on Migration Policy and Practice: The uses of Hypocrisy

Classical learning recognizes no role for international law in affecting migration policy and practice, but in modern times the salutary effects are increasing, although they remain modest. International law influences migration policy primarily through effective invocation of various forms of “soft law” in internal and international political forums. More limited prospects exist for beneficial changes enforced by international institutions and domestic courts. The article cautions against inflated expectations in the latter settings, however, particularly because overly ambitious claims can be counterproductive. It then offers a few predictions about near-term effects of international law, having to do with departures from a country, refugee law and the integration of migrants into their new homelands.

Safety, pharmacokinetics and pharmacodynamics of AMG 811, an anti-interferon-γ monoclonal antibody, in SLE subjects without or with lupus nephritis

OBJECTIVE

To evaluate safety, pharmacokinetics and pharmacodynamics of anti-interferon (IFN)-γ monoclonal antibody AMG 811 in subjects with SLE without or with lupus nephritis (LN).

METHODS

In this phase Ib, randomised, multiple-dose escalation study (NCT00818948), subjects without LN were randomised to subcutaneous AMG 811 (6, 20 or 60 mg) or placebo and subjects with LN were randomised to subcutaneous AMG 811 (20, 60 or 120 mg) or placebo every four weeks for three total doses. Outcomes included incidence of adverse events (AEs); pharmacokinetics; levels of serum proteins (CXCL-10, interleukin 18, monocyte chemotactic protein-1); changes in gene transcript profiles and clinical parameters (Safety of Estrogen in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) scores, proteinuria, anti-double-stranded DNA (anti-dsDNA) antibodies, C3 complement, C4 complement).

RESULTS

Fifty-six subjects enrolled (28 SLE without LN; 28 with LN). Baseline mean SELENA-SLEDAI scores were 2.2 and 12.0 for SLE subjects without and with LN, respectively. Most subjects reported an AE; no meaningful imbalances were observed between AMG 811 and placebo. Pharmacokinetic profiles were similar and mostly dose-proportional in subjects without or with LN. AMG 811 treatment reduced CXCL-10 protein levels and blood-based RNA IFN-γ Blockade Signature compared with placebo. Reductions were less pronounced and not sustained in subjects with LN, even at the highest dose tested, compared with subjects without LN. No effect on SELENA-SLEDAI scores, proteinuria, C3 or C4 complement levels, or anti-dsDNA antibodies was observed.

CONCLUSION

AMG 811 demonstrated favourable pharmacokinetics and acceptable safety profile but no evidence of clinical impact. IFN-γ-associated biomarkers decreased with AMG 811; effects were less pronounced and not sustained in LN subjects.

TRIAL REGISTRATION NUMBER

NCT00818948; results.

Effect of IL-17 receptor A blockade with brodalumab in inflammatory diseases

IL-17 cytokines are expressed by a variety of cells and mediate host defence against extracellular pathogens. IL-17 is upregulated at sites of inflammation and can synergize with other cytokines, such as TNF-α, to amplify the inflammatory response. Activation of these signalling pathways has been hypothesized to contribute to the underlying pathogenesis of several inflammatory diseases, including psoriasis, RA, PsA and asthma. Thus the IL-17 signalling pathway is an attractive target for the development of therapeutic agents to modulate aberrant inflammatory responses. This review of the clinical development of therapeutic agents that target IL-17 signalling pathways in inflammatory diseases focuses on brodalumab, a human anti-IL-17 receptor A mAb. The cumulative findings of early clinical studies with anti-IL-17 agents, including brodalumab, secukinumab and ixekizumab, provide strong evidence for the role of IL-17 signalling in the pathophysiology of certain inflammatory diseases and support the potential use of these agents in treating these diseases.

Brief Report: Pharmacodynamics, Safety, and Clinical Efficacy of AMG 811, a Human Anti-Interferon-γ Antibody, in Patients With Discoid Lupus Erythematosus

Objective

Interferon‐γ (IFNγ) is implicated in the pathogenesis of discoid lupus erythematosus (DLE). This study sought to evaluate a single dose of AMG 811, an anti‐IFNγ antibody, in patients with DLE.

Methods

The study was designed as a phase I randomized, double‐blind, placebo‐controlled crossover study of the pharmacodynamics, safety, and clinical efficacy of AMG 811 in patients with DLE. Patients received a single subcutaneous dose of AMG 811 (180 mg) or placebo. The patients in sequence 1 received AMG 811 followed by placebo, while those in sequence 2 received placebo followed by AMG 811. Pharmacodynamic end points included global transcriptional analyses of lesional and nonlesional skin, IFNγ blockade signature (IGBS) transcriptional scores in the skin and blood, keratinocyte IFNγ RNA scores, and serum levels of CXCL10 protein. Additional end points were efficacy outcome measures, including the Cutaneous Lupus Erythematosus Disease Area and Severity Index, and safety outcome measures.

Results

Sixteen patients with DLE were enrolled in the study (9 in sequence 1 and 7 in sequence 2). AMG 811 treatment reduced the IGBS score (which was elevated in DLE patients at baseline) in both the blood and lesional skin. The keratinocyte IFNγ RNA score was not affected by administration of AMG 811. Serum CXCL10 protein levels (which were elevated in the blood of DLE patients) were reduced with AMG 811 treatment. The AMG 811 treatment was well tolerated but did not lead to statistically significant improvements in any of the efficacy outcome measures.

Conclusion

AMG 811 treatment led to changes in IFNγ‐associated biomarkers and was well tolerated, but no significant clinical benefit was observed in patients with DLE.

Psychedelics Recruit Multiple Cellular Types and Produce Complex Transcriptional Responses Within the Brain

There has recently been a resurgence of interest in psychedelics, substances that profoundly alter perception and cognition and have recently demonstrated therapeutic efficacy to treat anxiety, depression, and addiction in the clinic. The receptor mechanisms that drive their molecular and behavioral effects involve activation of cortical serotonin 5-HT_2A receptors, but the responses of specific cellular populations remain unknown. Here, we provide evidence that a small subset of 5-HT_2A-expressing excitatory neurons is directly activated by psychedelics and subsequently recruits other select cell types including subpopulations of inhibitory somatostatin and parvalbumin GABAergic interneurons, as well as astrocytes, to produce distinct and regional responses. To gather data regarding the response of specific neuronal populations, we developed methodology for fluorescence-activated cell sorting (FACS) to segregate and enrich specific cellular subtypes in the brain. These methods allow for robust neuronal sorting based on cytoplasmic epitopes followed by downstream nucleic acid analysis, expanding the utility of FACS in neuroscience research.

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Psychedelics activate distinct transcription across cell types, including excitatory neurons, inhibitory neurons, and astrocytes

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Psychedelics induce internalization of 5-HT_2A receptors throughout the cortex and claustrum

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FACS can separate neuronal subpopulations that require non-nuclear markers

Psychedelic drugs are known to act through the 5-HT_2A receptor to produce many of their effects, however, the precise cellular populations in the brain which respond to this class of drugs remain unknown. We use flow cytometric analyses, immunohistochemistry, and gene expression analyses to identify small populations of specific cells in the brain that are activated by the psychedelic drug, (R)-DOI. The methodology used in these studies will be useful to determine the molecular effects of any manipulation or disease on particular brain cells.

Abstract 071: Adam17-mediated Neurogenic Hypertension Requires Neuronal Activation of At1a Receptors

We previously reported that neurogenic hypertension is associated with a reduction of Angiotensin Converting Enzyme 2 (ACE2) activity and an increase in A Disintegrin And Metalloprotease 17 (ADAM17) activity in the hypothalamus. Since ADAM17 is known to be expressed in multiple cell types and can be activated by various receptors, we tested the hypothesis that neuronal AT1a receptors (AT1aR) are necessary for ADAM17-mediated ACE2 shedding during neurogenic hypertension. DOCA-salt treatment (DOCA 1mg/g body weight sc + 1% saline p.o./3 weeks) was given to male neuronal AT1aR knockdown mice (AT1aR floxed crossed with Nefh-cre mice, 14-16 week-old) and their non-transgenic (NT) littermates (n=8/group). Following DOCA-salt treatment, enzyme activity assays were performed in hypothalamus of both DOCA-salt-treated and sham mice. Unlike in NT mice, ADAM17 activity was not increased by DOCA-salt treatment in the hypothalamus of neuronal AT1aR knockdown mice (153.7 ±23.8 vs. 128.5 ±11.6 FU/min, P =0.22). To assess whether impaired ADAM17 activation resulted from down-regulation of neuronal AT1aR, or was due to an attenuated BP rise, wild-type mice were infused with norepinephrine (NE; 4 ug/kg/min/14 d, n=6/group). Contrary to DOCA-salt hypertension, ACE2 activity in the hypothalamus remained intact during NE-induced hypertension and there was no significant increase in ADAM17 activity (59.1 ±4.3 vs. 52.3 ±11.7 FU/min, P =0.29). Using FACS, neurons, astrocytes and non-neuronal/non-astrocyte cells were sorted from the hypothalamus. A significant increase in ADAM17 mRNA resulting from DOCA-salt treatment (+1.72 ±0.19 fold vs. sham, P <0.05) was observed only in the neuronal population of NT mice but not in neuronal AT1aR knockdown mice. ERK phosphorylation, NOX4 expression and ROS production, all of which are involved in both intra- and extracellular mechanisms of ADAM17 activation were then assessed using Western blotting and DHE-staining. All were significantly impaired in the hypothalamus of neuronal AT1aR knock-down mice, compared to NT, after DOCA-salt treatment.

Taken together, our data provide strong evidence that activation of neuronal AT1aR is responsible for ADAM17-mediated ACE2 shedding and the maintenance of neurogenic hypertension.

Improved virologic outcomes over time for HIV-infected patients on antiretroviral therapy in a cohort from Rio de Janeiro, 1997-2011

BACKGROUND

Previous cohort studies have demonstrated the beneficial effects of antiretroviral therapy (ART) on viral load suppression. We aimed to examine the factors associated with virologic suppression for HIV-infected patients on ART receiving care at the Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation in Rio de Janeiro, Brazil.

METHODS

HIV-1 RNA levels and CD4+ T-cell counts at the date closest to midyear (1 July) were evaluated for 1,678 ART-naïve patients ≥ 18 years of age initiating ART between 1997 and 2010. The odds ratios (OR) and 95% confidence intervals (CI) for having an undetectable viral load (≤ 400 copies/mL) were estimated using generalized estimating equations regression models adjusted for clinical and demographic factors. Time-updated covariates included age, years since HIV diagnosis, hepatitis C diagnosis and ART interruptions.

RESULTS

Between 1997 and 2011, the proportion of patients with an undetectable viral load increased from 6% to 78% and the median [interquartile range] CD4+ T-cell count increased from 207 [162, 343] to 554 [382, 743] cells/μL. Pre-treatment median CD4+ T-cell count significantly increased over the observation period from 114 [37, 161] to 237 [76, 333] cells/μL (p < .001). The per-year adjusted OR (aOR) for having undetectable viral load was 1.18 (95% CI = 1.16-1.21). ART interruptions >1 month per calendar significantly decreased the odds [aOR = 0.32 (95% CI = 0.27-0.38)] of having an undetectable viral load. Patients initiating on a protease inhibitor (PI)-based first-line regimen were less likely to have undetectable viral load [aOR = 0.72 (95% CI = 0.63-0.83)] compared to those initiating on a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimen.

CONCLUSIONS

Our results demonstrate significant improvements in virologic outcomes from 1997 to 2011, which persisted after adjusting for other factors. This may in part be due to improvements in care and new treatment options. NNRTI- versus PI-based first-line regimens were found to be associated with increased odds of having an undetectable viral load, consistent with previous studies. Treatment interruptions were found to be the most important determinant of not having an undetectable viral load. Studies are needed to characterize the reasons for treatment interruptions and to develop subsequent strategies for improving adherence to ART.

Chronic LSD alters gene expression profiles in the mPFC relevant to schizophrenia

Chronic administration of lysergic acid diethylamide (LSD) every other day to rats results in a variety of abnormal behaviors. These build over the 90 day course of treatment and can persist at full strength for at least several months after cessation of treatment. The behaviors are consistent with those observed in animal models of schizophrenia and include hyperactivity, reduced sucrose-preference, and decreased social interaction. In order to elucidate molecular changes that underlie these aberrant behaviors, we chronically treated rats with LSD and performed RNA-sequencing on the medial prefrontal cortex (mPFC), an area highly associated with both the actions of LSD and the pathophysiology of schizophrenia and other psychiatric illnesses. We observed widespread changes in the neurogenetic state of treated animals four weeks after cessation of LSD treatment. QPCR was used to validate a subset of gene expression changes observed with RNA-Seq, and confirmed a significant correlation between the two methods. Functional clustering analysis indicates differentially expressed genes are enriched in pathways involving neurotransmission (Drd2, Gabrb1), synaptic plasticity (Nr2a, Krox20), energy metabolism (Atp5d, Ndufa1) and neuropeptide signaling (Npy, Bdnf), among others. Many processes identified as altered by chronic LSD are also implicated in the pathogenesis of schizophrenia, and genes affected by LSD are enriched with putative schizophrenia genes. Our results provide a relatively comprehensive analysis of mPFC transcriptional regulation in response to chronic LSD, and indicate that the long-term effects of LSD may bear relevance to psychiatric illnesses, including schizophrenia.

A semi-mechanistic model to characterize the pharmacokinetics and pharmacodynamics of brodalumab in healthy volunteers and subjects with psoriasis in a first-in-human single ascending dose study

Pharmacokinetic-pharmacodynamic (PK-PD) modeling can provide a framework for quantitative "learning and confirming" from studies in all phases of drug development. Brodalumab is a human monoclonal antibody (IgG2 ) targeting the IL-17 receptor A that blocks signaling by cytokines thought to play a central role in the pathogenesis of psoriasis (IL-17A, IL-17F, and IL-17A/F). We used semi-mechanistic modeling of single dose, first-in-human data to characterize the exposure-response relationship between brodalumab and the Psoriasis Area and Severity Index (PASI) in a Phase 1 clinical trial. Fifty-seven healthy volunteers and 25 subjects with moderate to severe psoriasis received single intravenous or subcutaneous administration of placebo or brodalumab (7-700 mg). A two-compartment model with parallel linear and nonlinear (Michaelis-Menten) elimination pathways described brodalumab PK. The PK-PASI relationship was characterized by linking a signaling compartment with an indirect response model of psoriatic plaques, where signaling suppressed plaque formation. The concentration of half-maximal inhibition IC50 was 2.86 µg/mL (SE: 50%). The endogenous psoriatic plaque formation rate of 0.862 (SE: 40%) PASI units/day was comparable with literature precedent. Despite the small sample size and single administration data, this semi-mechanistic modeling approach provided a quantitative framework to inform design of dose-ranging Phase 2 studies of brodalumab in psoriasis.

A phase Ib multiple ascending dose study evaluating safety, pharmacokinetics, and early clinical response of brodalumab, a human anti-IL-17R antibody, in methotrexate-resistant rheumatoid arthritis

INTRODUCTION

The aim of this study was to evaluate the safety, pharmacokinetics, and clinical response of brodalumab (AMG 827), a human, anti-IL-17 receptor A (IL-17RA) monoclonal antibody in subjects with moderate-to-severe rheumatoid arthritis (RA).

METHODS

This phase Ib, randomized, placebo-controlled, double-blind multiple ascending dose study enrolled subjects with moderate to severe RA (≥ 6/66 swollen and ≥ 8/68 tender joints). Subjects were randomized 3:1 to receive brodalumab (50 mg, 140 mg, or 210 mg subcutaneously every two weeks for 6 doses per group; or 420 mg or 700 mg intravenously every 4 weeks for two doses per group) or placebo. Endpoints included incidence of adverse events (AEs) and pharmacokinetics. Exploratory endpoints included pharmacodynamics, and improvements in RA clinical metrics.

RESULTS

Forty subjects were randomized to investigational product; one subject discontinued due to worsening of RA (placebo). The study was not designed to assess efficacy. AEs were reported by 70% (7/10) of placebo subjects and 77% (22/30) of brodalumab subjects. Three serious AEs were reported in two subjects; there were no opportunistic infections. Brodalumab treatment resulted in inhibition of IL-17 receptor signaling and receptor occupancy on circulating leukocytes. No treatment effects were observed with individual measures of RA disease activity. On day 85 (week 13) 37% (11/30) of brodalumab subjects and 22% (2/9) of placebo subjects achieved ACR20; 7% (2/30) brodalumab subjects and 11% (1/9) of placebo subjects achieved ACR50; and 0% (0/30) brodalumab subjects and 0% (0/9) of placebo subjects achieved ACR70.

CONCLUSIONS

Multiple dose administration of brodalumab was tolerated in subjects with active RA. There was no evidence of a clinical response to brodalumab in subjects with RA.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT00771030.

Prenatal Dietary Docosahexaenoic Acid Supplementation in Combination with Protein Restriction Does Not Affect Blood Pressure in Adult Wistar Rats

Recent findings indicate that prenatal protein restriction, which leads to elevated blood pressure in adult rats, results in decreased levels of docosahexaenoic acid (DHA) in neonatal rat brain. In light of the evidence of a relationship between dietary DHA and adult blood pressure, the purpose of this study was to ascertain whether prenatal dietary supplementation with DHA would prevent the development of hypertension associated with maternal protein restriction. Throughout gestation, female Wistar rats were fed isocaloric diets containing either 18% casein + 10% corn oil (CON; control), 9% casein + 10% corn oil (LP; low-protein) or 9% casein + 8.5% corn oil + 1.5% DHASCO (LP + 0.6% DHA). DHA increased levels of DHA in neonatal forebrain but there were no effects of LP. At 10 weeks there were no dietary effects on blood pressure measured on four consecutive days using tail-cuff plethysmography. There were also no significant effects measured at 30 weeks, using femoral artery catheterisation, despite adequate power to detect a 10 mm Hg difference. Trends in corticosterone measurements suggested higher stress reactivity in the LP group. These results do not provide strong support for the prenatal low protein model of hypertension and a relation with dietary DHA.

The IL-23/T17 pathogenic axis in psoriasis is amplified by keratinocyte responses

Psoriasis is a complex inflammatory process resulting from activation of the well-defined interleukin (IL)-23/T17 cytokine axis. We review the role of key cytokines IL-17 and IL-23 in psoriasis, as well as tumor necrosis factor (TNF)α, focusing on therapeutic cytokine interventions and what they reveal about psoriatic inflammation. The potential role of recently described epidermal IL-36RN and CARD14 genetic mutations in psoriasis pathogenesis is also explored, because they augment keratinocyte responses to proinflammatory cytokines. The discovery of these genetic mutations in familial and pustular psoriasis suggests new links between cytokine-induced gene products and IL-1 family members from keratinocytes, which may regulate features of the disease, including epidermal hyperplasia and neutrophil infiltrating responses.

Autoimmunity stimulated by adoptively transferred dendritic cells is initiated by both alphabeta and gammadelta T cells but does not require MyD88 signaling

Vaccination of nonautoimmune prone mice with syngeneic dendritic cells (DC) readily induces anti-DNA autoantibodies but does not trigger systemic disease. We observed that anti-DNA autoantibody generation absolutely required alphabeta T cells and that gammadelta T cells also contributed to the response, but that regulatory T cells restrained autoantibody production. Although both NZB/W F(1) mice and DC vaccinated C57/BL6 mice produced autoantibodies against dsDNA, vaccinated mice had higher levels of Abs against H1 histone and lower levels of antinucleosome Abs than NZB/W F(1) mice. Despite a 100-fold increase in IL-12 and Th1 skewing to a foreign Ag, OVA, synergistic TLR activation of DC in vitro failed to augment anti-DNA Abs or promote class switching beyond that induced by LPS alone. TLR stimulation was not absolutely required for the initial loss of B cell tolerance because anti-DNA levels were similar when wild-type (WT) or MyD88-deficient DC were used for vaccination or WT and MyD88-deficient recipients were vaccinated with WT DC. In contrast, systemic administration of LPS, augmented anti-DNA Ab levels and promoted class switching, and this response was dependent on donor DC signaling via MyD88. LPS also augmented responses in the MyD88-deficient recipients, suggesting that LPS likely exerts its effects on both transferred DC and host B cells in vivo. These results indicate that both the alphabeta and gammadelta subsets are necessary for promoting autoantibody production by DC vaccination, and that although TLR/MyD88 signaling is not absolutely required for initiation, this pathway does promote augmentation, and Th1-mediated skewing, of anti-DNA autoantibodies.

Innate and adaptive immune response to apoptotic cells

The immune system is constantly exposed to dying cells, most of which arise during central tolerance and from effete circulating immune cells. Under homeostatic conditions, phagocytes (predominantly macrophages and dendritic cells) belonging to the innate immune system, rapidly ingest cells and their debris. Apoptotic cell removal requires recognition of altered self on the apoptotic membrane, a process which is facilitated by natural antibodies and serum opsonins. Recognition, may be site and context specific. Uptake and ingestion of apoptotic cells promotes an immunosuppressive environment that avoids inflammatory responses to self-antigens. However, it does not preclude a T cell response and it is likely that constant exposure to self-antigen, particularly by immature dendritic cells, leads to T cell tolerance. Tolerance occurs by several different mechanisms including anergy and deletion (for CD8+T cells) and induction of T regulatory cells (for CD4+T cells). Failed apoptotic cell clearance promotes immune responses to self-antigens, especially when the cellular contents are leaked from the cell (necrosis). Inflammatory responses may be induced by nucleic acid stimulation of Toll like receptors and other immune sensors, specific intracellular proteins and non-protein (uric acid) stimulation of inflammasomes.

Autoantibodies make a U-turn: the toll hypothesis for autoantibody specificity

Like the immune response itself, our efforts to understand the "rules" for self-nonself discrimination are constantly evolving. The discovery of pattern recognition receptors-the Toll-like receptor (TLR) family in particular-shifted the emphasis of self-nonself recognition from lymphocytes functioning in the adaptive immune system to antigen-presenting cells (APCs) functioning in the innate immune system. Two new articles, one in a recent issue (1) and one in this issue (see Vollmer et al. [2] on p. 1575), demonstrate that antigen-antibody complexes containing RNAs activate B lymphocytes and dendritic cells (DCs) through interaction with TLR7 and/or TLR8. From these and other papers, one begins to see how specific types of autoantigens-by virtue of their capacity to act as TLR ligands-favor autoantibody production. This is known as the Toll hypothesis.

Intracellular mammalian DNA stimulates myeloid dendritic cells to produce type I interferons predominantly through a toll-like receptor 9–independent pathway

OBJECTIVE

Exogenous nucleic acids, including bacterial unmethylated DNA and viral single-stranded RNA, are potent activators of innate immunity through interaction with the Toll-like receptors (TLRs). In contrast, mammalian DNA has been generally thought to have a limited activation effect, or even a suppressive effect, on innate immunity. Since DNA is a major component of dying cells and recent studies indicate that mammalian nucleic acids may be stimulatory under certain conditions, we undertook this study to examine the effect of intracellular mammalian DNA on myeloid dendritic cell (DC) activation.

METHODS

Mammalian DNA was introduced into murine bone marrow-derived DCs (BMDCs) by transfection. BMDC activation was determined by flow cytometry (CD40, CD86). Production of tumor necrosis factor alpha and interleukin-6 was measured by enzyme-linked immunosorbent assay, and production of type I interferons (IFNs) by bioassay. Parallel studies were conducted using BMDCs from mice deficient in myeloid differentiation 88 (MyD88), TLR-9, and IFNalpha/beta receptor.

RESULTS

Intracellular mammalian DNA activated immature BMDCs, as determined by the up-regulation of CD40 and CD86 as well as by the production of significant quantities of type I IFN. The interferogenic response was shown to be relatively independent of TLR-9, and the TLR adaptor MyD88. The IFN response to intracellular DNA was reduced in BMDCs lacking IFNalpha/beta receptor but was intact in embryonic fibroblasts lacking protein kinase R.

CONCLUSION

These results indicate that intracellular DNA stimulates BMDC maturation and IFN production predominantly through a TLR-independent pathway, and support a model whereby inefficient clearance and/or degradation of endogenous DNA may stimulate innate immune responses similar to the TLR-independent response to exogenous (i.e., viral) double-stranded RNA.

West Nile virus infection and serologic response among persons previously vaccinated against yellow fever and Japanese encephalitis viruses

It is hypothesized that previous heterologous flaviviral exposure may modulate clinical illness among persons infected with West Nile virus (WNV). Little is known about the serological response in such persons. In summer 2003, a WNV outbreak occurred in Colorado, the location of the Centers for Disease Control and Prevention, Division of Vector-Borne Infectious Diseases (DVBID). DVBID employees, most previously vaccinated with yellow fever virus (YFV) or Japanese encephalitis virus (JEV) vaccines, were studied to determine whether previous vaccination affected symptom development among those subsequently infected with WNV during the outbreak, as well as their serological response. Serum samples collected in December 2003 and previously banked samples were tested using the plaque reduction neutralization test (PRNT) against WNV, Saint Louis encephalitis virus, dengue- 4 virus, JEV, and YFV. Specimens shown to have WNV antibody by PRNT were tested by IgM and IgG enzymelinked immunosorbent assays (ELISAs). Ten (9%) of 113 serosurvey participants had WNV neutralizing antibody titers in December 2003. PRNT titers from previous specimens showed that one of the ten had seroconverted to WNV before 2003. Of the remaining nine participants, seven reported illness in the summer of 2003, two of which were unvaccinated and five previously vaccinated. In the December 2003 specimens, five persons previously unvaccinated or vaccinated only against YFV had a fourfold or greater neutralizing titer with WNV than with other flaviviruses, whereas no persons previously vaccinated against JEV or JEV and YFV showed a similar difference in neutralizing titers. Eight of nine persons infected in 2003 had negative or indeterminate WNV MAC-ELISA results in the December 2003 sample; the ninth person was vaccinated against YFV one month previously, and was also YFV positive by MAC-ELISA. We conclude that previous flaviviral vaccination does not markedly affect the development of WNV fever and that the IgM antibody response in patients without neuroinvasive WNV disease is transient.

Mechanisms of apoptosis

The understanding of the apoptotic program has grown exponentially over the past decade. Numerous human diseases have been directly linked to genetic defects in the apoptotic pathways, including cancer, neurodegenerative disorders, and autoimmune diseases. Caspases initiate and amplify various death signals, allowing for selective and ordered cellular demolition. The fine balance between pro- and antiapoptotic Bcl-2 family members regulates the cell fate in response to many (but not all) stress or signaling pathways. Recent discoveries highlight the complex integration of signals from various organelles that determine cell fate and the multiple functions of central players in the apoptotic process. It is likely that the knowledge obtained in a relatively time will translate into better diagnostics and therapies to enhance or retard cell death in the appropriate clinical circumstances.

Filgrastim support during combination chemotherapy using cisplatin, doxorubicin, and cyclophosphamide to treat advanced or recurrent endometrial cancer: a clinical study and literature review

In a private practice setting, 16 patients with advanced or recurrent endometrial carcinoma received cisplatinum 50 mg/m2, doxorubicin 50 mg/m2, and cyclophosphamide 750 mg/m2 every three weeks. Growth factor support using filgrastim was initiated on the first cycle of therapy and each subsequent cycle. Sixteen patients were entered into the study with 13 being evaluable. No patient had previously received chemotherapy. The overall response rate was 54% with two complete responses (15%) and five partial responses (38%). Stable disease was seen in 46% of patients. Progression-free survival was observed to be a median of 8.5 months for a complete response, a median of 8.5 months for a partial response and a median of 7 months for stable disease. Fifteen percent of the patients and 3% of all chemotherapy cycles had febrile neutropenic events. There were no deaths due to myelotoxicity. Only one patient required a dose reduction due to neutropenia. Four of the 13 patients required dose reductions due to previous nadir thrombocytopenia. Grade 4 granulocytopenia occurred in 28% of treatment cycles and grade 3 granulocytopenia occurred in 12% of treatment cycles. The use of filgrastim (G-CSF) allowed patients to stay on therapy for an average of seven treatments. Neutropenia was not the dose-limiting toxicity from this dose-intense regimen.

A dose-escalating study of weekly bolus topotecan in previously treated ovarian cancer patients

OBJECTIVE

Topotecan is an established topoisomerase I inhibitor for the treatment of relapsed ovarian cancer. Myelotoxicity and suboptimal patient convenience associated with daily topotecan, however, have prompted investigators to explore alternate regimens, including a weekly regimen of topotecan. The objective of this study was to determine the maximum tolerated dose (MTD) of topotecan given as a weekly bolus in previously treated ovarian cancer patients.

METHODS

Second- and third-line ovarian cancer patients with measurable disease or elevated cancer antigen 125 received weekly bolus topotecan intravenously starting at 1.5 mg/m(2). Topotecan was escalated in dose increments of 0.5 mg/m(2) every 21 days as tolerability allowed. Dose-limiting toxicity was defined as grade 3/4 neutropenia or thrombocytopenia.

RESULTS

Thirty-two of 35 patients were evaluable for safety and tolerability. No notable toxicity was observed with weekly topotecan doses < 4 mg/m(2). Additionally, there was an absence of dose-limiting myelotoxicity and thrombocytopenia with weekly topotecan. The MTD of weekly topotecan without the use of granulocyte colony-stimulating factor support was 4 mg/m(2), with grade 2 anemia, chronic fatigue, and grade 2 gastrointestinal toxicity limiting further dose escalation. Weekly topotecan also demonstrated antitumor activity at doses >2 mg/m(2).

CONCLUSIONS

The establishment of a well-tolerated, weekly regimen of topotecan (4 mg/m(2), with a maximum recommended dose of 6 mg/m(2)) provides the basis for further investigation in phase II studies of single-agent and combination regimens in previously treated ovarian cancer patients.

Epidemic West Nile encephalitis, New York, 1999: results of a household-based seroepidemiological survey

BACKGROUND

In the summer of 1999, West Nile virus was recognised in the western hemisphere for the first time when it caused an epidemic of encephalitis and meningitis in the metropolitan area of New York City, NY, USA. Intensive hospital-based surveillance identified 59 cases, including seven deaths in the region. We did a household-based seroepidemiological survey to assess more clearly the public-health impact of the epidemic, its range of illness, and risk factors associated with infection.

METHODS

We used cluster sampling to select a representative sample of households in an area of about 7.3 km(2) at the outbreak epicentre. All individuals aged 5 years or older were eligible for interviews and phlebotomy. Serum samples were tested for IgM and IgG antibodies specific for West Nile virus.

FINDINGS

677 individuals from 459 households participated. 19 were seropositive (weighted seroprevalence 2.6% [95% CI 1.2-4.1). Six (32%) of the seropositive individuals reported a recent febrile illness compared with 70 of 648 (11%) seronegative participants (difference 21% [0-47]). A febrile syndrome with fatigue, headache, myalgia, and arthralgia was highly associated with seropositivity (prevalence ratio 7.4 [1.5-36.6]). By extrapolation from the 59 diagnosed meningoencephalitis cases, we conservatively estimated that the New York outbreak consisted of 8200 (range 3500-13000) West Nile viral infections, including about 1700 febrile infections.

INTERPRETATION

During the 1999 West Nile virus outbreak, thousands of symptomless and symptomatic West Nile viral infections probably occurred, with fewer than 1% resulting in severe neurological disease.

West Nile virus recombinant DNA vaccine protects mouse and horse from virus challenge and expresses in vitro a noninfectious recombinant antigen that can be used in enzyme-linked immunosorbent assays

Introduction of West Nile (WN) virus into the United States in 1999 created major human and animal health concerns. Currently, no human or veterinary vaccine is available to prevent WN viral infection, and mosquito control is the only practical strategy to combat the spread of disease. Starting with a previously designed eukaryotic expression vector, we constructed a recombinant plasmid (pCBWN) that expressed the WN virus prM and E proteins. A single intramuscular injection of pCBWN DNA induced protective immunity, preventing WN virus infection in mice and horses. Recombinant plasmid-transformed COS-1 cells expressed and secreted high levels of WN virus prM and E proteins into the culture medium. The medium was treated with polyethylene glycol to concentrate proteins. The resultant, containing high-titered recombinant WN virus antigen, proved to be an excellent alternative to the more traditional suckling-mouse brain WN virus antigen used in the immunoglobulin M (IgM) antibody-capture and indirect IgG enzyme-linked immunosorbent assays. This recombinant antigen has great potential to become the antigen of choice and will facilitate the standardization of reagents and implementation of WN virus surveillance in the United States and elsewhere.

Pharmacy in family practice: a description and evaluation

Expanded pharmacy functions within a private practice setting are described. These activities are a component of a pharmacy training program. The medical practitioners evaluated the program, eliciting an overall positive response. Additionally, future services were priority rated by the staff, demonstrating more accessibility to the services, patient education, and chronic disease care programs as the most desirable projects. As the Clinic and the medical residency expand, the activities of the clinical pharmacist shall continue to develop.

West Nile encephalitis in Israel, 1999: the New York connection

We describe two cases of West Nile (WN) encephalitis in a married couple in Tel Aviv, Israel, in 1999. Reverse transcription-polymerase chain reaction performed on a brain specimen from the husband detected a WN viral strain nearly identical to avian strains recovered in Israel in 1998 (99.9% genomic sequence homology) and in New York in 1999 (99.8%). This result supports the hypothesis that the 1999 WN virus epidemic in the United States originated from the introduction of a strain that had been circulating in Israel.

Standardization of immunoglobulin M capture enzyme-linked immunosorbent assays for routine diagnosis of arboviral infections

Immunoglobulin M antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA) is a rapid and versatile diagnostic method that readily permits the combination of multiple assays. Test consolidation is especially important for arthropod-borne viruses (arboviruses) which belong to at least three virus families: the Togaviridae, Flaviviridae, and Bunyaviridae. Using prototype viruses from each of these families and a panel of well-characterized human sera, we have evaluated and standardized a combined MAC-ELISA capable of identifying virus infections caused by members of each virus family. Furthermore, by grouping antigens geographically and utilizing known serological cross-reactivities, we have reduced the number of antigens necessary for testing, while maintaining adequate detection sensitivity. We have determined that a 1:400 serum dilution is most appropriate for screening antiviral antibody, using a positive-to-negative ratio of >/=2.0 as a positive cutoff value. With a blind-coded human serum panel, this combined MAC-ELISA was shown to have test sensitivity and specificity that correlated well with those of other serological techniques.

Detection of anti-arboviral immunoglobulin G by using a monoclonal antibody-based capture enzyme-linked immunosorbent assay

Monoclonal antibody (MAb)-based capture enzyme-linked immunosorbent assays (ELISAs) for the detection of anti-arboviral immunoglobulin G (IgG ELISAs) were developed for a comprehensive array of medically important arboviruses from the Alphavirus, Flavivirus, and Bunyavirus genera. Tests were optimized and standardized so that maximum homology could be maintained among working parameters for the different viral agents, enabling a wide range of viruses to be easily tested for at one time. MAbs were screened for suitability as capture vehicles for antigens from the three genera. The final test configuration utilized group-reactive MAbs eastern equine encephalitis virus 1A4B-6, dengue 2 virus 4G2, and La Crosse encephalitis virus 10G5.4 to capture the specific inactivated viral antigens. Serum IgG was detected by using alkaline phosphatase-conjugated anti-human IgG (Fc portion). A dilution of 1:400 was chosen as the universal screening serum dilution, with endpoint titrations of serum samples testing positive eliminating occasional false-positive results. IgG ELISA results correlated with those of the standard plaque-reduction neutralization assays. As expected, some test cross-reactivity was encountered within the individual genera, and tests were interpreted within the context of these reactions. The tests were standardized for laboratory diagnosis of arboviral infections, with the intent that they be used in tandem with the corresponding IgM antibody-capture ELISAs.

O'nyong-nyong fever in south-central Uganda, 1996-1997: clinical features and validation of a clinical case definition for surveillance purposes

O'nyong-nyong (ONN) fever, caused by infection with a mosquito-borne central African alphavirus, is an acute, nonfatal illness characterized by polyarthralgia. During 1996-1997, south-central Uganda experienced the second ONN fever epidemic ever recognized. Among 391 persons interviewed and sampled, 40 cases of confirmed and 21 of presumptive, well-characterized acute, recent, or previous ONN fever were identified through active case-finding efforts or during a household serosurvey and by the application of clinical and laboratory criteria. Among confirmed cases, the knees and ankles were the joints most commonly affected. The median duration of arthralgia was 6 days (range, 2-21 days) and of immobilization was 4 days (range, 1-14 days). In the majority, generalized skin rash was reported, and nearly half had lymphadenopathy, mainly of the cervical region. Viremia was documented in 16 cases, primarily during the first 3 days of illness, and in some of these, body temperature was normal. During this epidemic, the combination of fever, arthralgia, and lymphadenopathy had a specificity of 83% and a sensitivity of 61% in the identification of cases of ONN fever and thus could be useful for surveillance purposes.

Defective CD95/APO-1/Fas signal complex formation in the human autoimmune lymphoproliferative syndrome, type Ia

Heterozygous mutations in the CD95 (APO-1/Fas) receptor occur in most individuals with autoimmune lymphoproliferative syndrome (ALPS) and dominantly interfere with apoptosis by an unknown mechanism. We show that local or global alterations in the structure of the cytoplasmic death domain from nine independent ALPS CD95 death-domain mutations result in a failure to bind the FADD/MORT1 signaling protein. Despite heterozygosity for the abnormal allele, lymphocytes from ALPS patients showed markedly decreased FADD association and a loss of caspase recruitment and activation after CD95 crosslinking. These data suggest that intracytoplasmic CD95 mutations in ALPS impair apoptosis chiefly by disrupting death-domain interactions with the signaling protein FADD/MORT1.

Molecular genetic studies in lymphocyte apoptosis and human autoimmunity

Using a genetic approach, we have studied the molecular basis of human autoimmunity with special emphasis on a disease that is due to defective lymphocyte apoptosis. Recently, we and our collaborators have found that the autoimmune/lymphoproliferative syndrome (ALPS), an inherited disease of children comprising marked lymphoid hyperplasia and autoimmune manifestations, is due to abnormalities in the CD95 gene that cause defective lymphocyte apoptosis. Our recent investigations have shown that the mutations in most families with ALPS cause either global or local changes in the structure of a cytoplasmic portion of the molecule called the 'death domain'. These death domain alterations impair binding of the adapter protein FADD/MORT1 and result in a failure to activate apoptotic caspases after CD95 (Fas/APO-1) cross-linking. Mutations in apoptotic caspases may also contribute to the pathogenesis of ALPS in individuals that have no CD95 gene mutations.

Synthesis and structure-activity relationships of 2-pyrazinylcarboxamidobenzoates and beta-ionylideneacetamidobenzoates with retinoidal activity

The structure-activity relationships of two series of novel retinoids (2-pyrazinylcarboxamidobenzoates and beta-ionylideneacetamidobenzoates) have been investigated by evaluating their ability to induce differentiation in both human promyelocytic leukemia (HL60) cells and mouse embryonal carcinoma (P19) cells. The most active compound (ED50 = 8.3 x 10(-9) M) of the 2-pyrazinylcarboxamidobenzoates is 4-[2-(5,6,7,8-tetrahydro-5,5,8, 8-tetramethylquinoxalyl)carboxamido]benzoic acid (9u), while the most active analogue of the beta-ionylideneacetamidobenzoates is 4-[3-methyl-5-(2',6',6'-trimethyl-1'-cyclohexen-1'-yl)-(2E, 4E)-pentadienamido]benzoic acid (10a, ED50 = 3.2 x 10(-8) M). Our studies identify an absolute requirement for the carboxylic acid moiety on the aromatic ring to be para relative to the amide linkage for activity. Benzoate substitutions in the ortho position relative to the terminal carboxylate (9d,k,r) are well-tolerated; however, a methoxy substituent meta relative to the terminal carboxylate gives rise to only weakly active analogues (9x). Conformational studies (NMR, X-ray crystallography) of the 2-pyrazinylcarboxamidobenzoates indicate that the preferred conformation exhibits a trans-amide bond and an internal hydrogen bond between the quinoxaline N1 and HN amide which locks the torsional angle between C2 and CO in the s-trans conformation. N-Methylation (9y) results in loss of activity. Studies indicate that there is now a cis-amide bond present which redirects the carboxylate toward the pharmacophoric gem-dimethyl groups. The distance between the gem-dimethyl group and the terminal carboxylate appears to be too short to activate the retinoid receptor. N-Methylation in the beta-ionylideneacetamidobenzoate series (10c) also results in the formation of a cis-amide bond and loss of activity.

Death-effector filaments: novel cytoplasmic structures that recruit caspases and trigger apoptosis

The death-effector domain (DED) is a critical protein interaction domain that recruits caspases into complexes with members of the TNF-receptor superfamily. Apoptosis can also be induced by expressing certain DED-containing proteins without surface receptor cross-linking. Using Green Fluorescent Protein to examine DED-containing proteins in living cells, we show that these proteins cause apoptosis by forming novel cytoplasmic filaments that recruit and activate pro-caspase zymogens. Formation of these filaments, which we term death-effector filaments, was blocked by coexpression of viral antiapoptotic DED-containing proteins, but not by bcl-2 family proteins. Thus, formation of death-effector filaments allows a regulated intracellular assembly of apoptosis-signaling complexes that can initiate or amplify apoptotic stimuli independently of receptors at the plasma membrane.