Characteristics and 6-Month Outcomes in Patients with Rheumatoid Arthritis Initiating Infliximab Biosimilar IFX-dyyb in a Real-World Setting

INTRODUCTION

Real-world studies describing biosimilar initiation or switching in patients with rheumatoid arthritis (RA) are limited. The aim of this study was to assess treatment patterns and effectiveness of real-world patients with RA initiating infliximab biosimilar IFX-dyyb (CT-P13; Inflectra®) in the USA.

METHODS

This observational study evaluated patients with RA from the CorEvitas RA Registry who initiated IFX-dyyb and had Clinical Disease Activity Index (CDAI) recorded at baseline and 6 months. The primary outcome was reaching low disease activity (LDA; CDAI ≤ 10) at 6 months in patients with moderate or high disease activity (CDAI > 10) at baseline. Secondary outcomes were change at 6 months in CDAI and certain patient-reported outcomes (PROs). Patient data were stratified by prior treatment: biologic/targeted synthetic disease-modifying antirheumatic drug (tsDMARD)-naïve, reference infliximab (IFX-REF) or IFX biosimilar, or a non-IFX biologic or tsDMARD.

RESULTS

Of 318 patients initiating IFX-dyyb, 176 had baseline and 6-month CDAI scores; 73 (41%) switched from IFX, 61 (35%) switched from another non-IFX/biologic/tsDMARD, 32 (18%) were naïve to biologics/tsDMARDs, and 10 (6%) switched from an IFX biosimilar. Among patients with moderate or high disease activity at baseline, 32.9% (95% CI 22.9, 42.9) achieved LDA at 6 months. Mean 6-month change from baseline in CDAI was - 1.8 (95% CI - 3.3, - 0.3) overall; - 4.7 (- 7.6, - 1.7) in patients who switched from a non-IFX biologic/tsDMARD, - 4.1 (- 7.8, - 0.3) in biologic/tsDMARD-naïve patients, and 1.1 (- 0.4, 2.6) in patients who switched from IFX-REF/IFX biosimilar. Other clinical outcomes/PROs improved at 6 months. Of the IFX-dyyb initiators, 68% remained on IFX-dyyb at 6 months.

CONCLUSION

In this real-world population of patients with RA initiating IFX-dyyb, the majority switched from IFX-REF or a non-IFX biologic/tsDMARD. CDAI remained stable in patients switching from IFX-REF/IFX biosimilar and improved in patients switching from a non-IFX biologic/tsDMARD and in biologic/tsDMARD-naïve patients.

978 Improving Satisfaction in Patients with Learning Disabilities

Aim

Patients with learning disabilities (LD) are less satisfied because they do not fully understand their surgical management. Poor communication between doctors & LD patients leaves them unhappy & reluctant to seek further help. We aimed to improve satisfaction in 90% of patients.

Method

In one year in a midlands DGH 201 patients with an LD were admitted. Interviews were conducted which highlighted key problems. Multiple ideas were reviewed, and the simple but effective intervention was a brightly coloured prompt sheet with 4 questions placed in the patient notes: Have you explained:

A simple scale tracked the patient & carer satisfaction over 8 weeks as the prompt sheets were introduced to patient notes by the learning disability nurses.

Results

A 90% increase in patient satisfaction was not achieved but considerable positive feedback was. Moreover, the LD nurses witnessed an increased use of hospital passports among doctors as well as improved patient-doctor communication. A small target population restricts the rapid collection of large amounts of data. The patient satisfaction measure was qualitative, and a 10-point scale would have detailed smaller changes. Lack of carer continuity also made it difficult to collect consistent data.

Conclusions

The role of learning disability nurses is key to improving patient understanding and satisfaction, but they can be assisted by channelling and maintaining initiatives to raise awareness of the needs of these patients.

Association of High Serum Interleukin-6 Levels With Severe Progression of Rheumatoid Arthritis and Increased Treatment Response Differentiating Sarilumab From Adalimumab or Methotrexate in a Post Hoc Analysis

Objective

The development of biomarkers to guide treatment decisions is a major research focus in rheumatoid arthritis (RA). Patients with RA have elevated interleukin‐6 (IL‐6) levels; however, the utility of IL‐6 as a predictor of treatment response is unclear. This study was undertaken to investigate, by post hoc analysis, whether baseline IL‐6 levels are predictive of sarilumab treatment responses in 2 phase III studies.

Methods

Serum IL‐6 concentrations were measured in patients with RA prior to receiving sarilumab 200 mg (n = 148) or adalimumab 40 mg (n = 152) every 2 weeks (in the MONARCH trial; ClinicalTrials.gov identifier: NCT02332590) or sarilumab 150 mg, sarilumab 200 mg, or placebo every 2 weeks plus methotrexate (MTX) (n = 401, n = 396, and n = 397, respectively) (in the MOBILITY trial; ClinicalTrials.gov identifier: NCT01061736). Efficacy and patient‐reported outcomes were compared between and within groups according to IL‐6 tertile using linear and logistic regression.

Results

In MONARCH, patients with high baseline IL‐6 levels (all ≥3 times the upper limit of normal; n = 100) had higher disease activity at baseline than those with low IL‐6 levels (n = 100). The magnitude of clinical improvement over 24 weeks with sarilumab versus adalimumab was greater in patients with high compared to those with low baseline IL‐6 levels. In MOBILITY, compared to patients with low IL‐6 levels (n = 397), patients with high IL‐6 levels (n = 398) had higher disease activity and joint damage at baseline, were more likely to have joint progression, and had less clinical improvement over 52 weeks’ treatment with placebo plus MTX compared to sarilumab 150 mg or 200 mg plus MTX. Baseline IL‐6 and C‐reactive protein levels were both predictive of outcomes. Safety profiles were similar between defined IL‐6 tertiles.

Conclusion

IL‐6 may be a prognostic marker of disease progression and severity, and patients with high IL‐6 levels may be likely to benefit from sarilumab compared to adalimumab or MTX. Prospective validation is warranted to confirm the results of these post hoc analyses.

A198 EOSINOPHILIC ESOPHAGITIS WITH STRICTURE PRESENTING SHORTING AFTER INITIATION OF ORAL PEANUT IMMUNOTHERAPY

Background

Oral immunotherapy (OIT) is increasingly practiced outside of research settings with reasonable success (Soller 2019).

With OIT, a patient eats their food allergen daily, gradually increasing the dose, with the goal to prevent or reduce the severity of an anaphylactic reaction.

One of the described adverse events of OIT is a risk of developing Eosinophilic Esophagitis (EoE), with cited frequency of 2.7% (Lucendo 2014). In addition, OIT is typically contraindicated in patients with known EoE but patients are not routinely screened for EoE prior to initiation of OIT.

Aims

To present a case of a 12 year old boy with peanut anaphylaxis who developed eosinophilic esophagitis and an esophageal stricture shortly after starting peanut immunotherapy

Methods

Patient chart review was conducted. A literature review was done using the words “eosinophilic esophagitis” and “immunotherapy”.

Results

A12 year old boy with asthma, allergic rhinitis and multiple anaphylactic food allergies, started peanut OIT with an allergist. Prior to OIT, the patient had no symptoms suggestive of EoE such as dysphagia, heartburn, chest pain or washing of food. Approximately 3.5 weeks into treatment, the patient developed daily vomiting. The patient was advised to stop the peanut OIT three days after symptom onset, but the vomiting continued for another 8 days. By the time of endoscopy (16 days after onset of vomiting), the vomiting had completely subsided for the previous five days.

The upper GI endoscopy demonstrated signs of EoE throughout the length of the esophagus. In the mid esophagus there was resistance where the 9.8 mm gastroscope was unable to pass. A smaller gastroscope with a 5.9 mm width was easily able to pass through the stricture. Histology showed marked eosinophilia throughout the esophagus with basal cell hyperplasia, spongiosis, superficial microabscesses and stromal fibrosis consistent with EoE. The patient continued to be ‘asymptomatic’ at the time of endoscopy and after despite the presence of a stricture. After discussion, the patient was started on oral viscous budesonide (OVB) 1mg PO BID.

The patient was re-scoped 4 weeks into OVB therapy with complete resolution of the stricture with neither macroscopic nor histologic findings of EoE. Patient is now off OVB for over a month, remains asymptomatic, and will undergo repeat endoscopy in the upcoming month to ensure normal histology

Conclusions

This is the first case describing EoE with an esophageal stricture shortly after initiation of OIT. Pediatric Gastroenterologists need to be increasingly aware that patients undergoing OIT are at an increasing risk of ‘developing’ or at least ‘unmasking’ EoE. More research is required to evaluate whether EoE screening, by symptom questionnaire or endoscopy is warranted prior to beginning OIT, and whether OIT is truly needed.

Funding Agencies

CAG

Systematic review: efficacy and safety of switching patients between reference and biosimilar infliximab

BACKGROUND

Biosimilar versions of widely prescribed drugs, including the tumour-necrosis factor antagonist infliximab, are becoming increasingly available. As biosimilars are not identical copies of reference products, evidence may be required to demonstrate that switching between a reference biologic and biosimilars is safe and efficacious. To establish interchangeability, US Food and Drug Administration guidance states that studies must demonstrate that biosimilars remain equivalent or non-inferior to a reference product after multiple switches between products.

AIMS

To investigate the evidence evaluating the safety and efficacy of switching between reference and biosimilar infliximab in patients with inflammatory disorders, including Crohn's disease, ulcerative colitis, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, and plaque psoriasis.

METHODS

Published studies presenting data on switching between reference and biosimilar infliximab were identified by searching the MEDLINE database. Congress abstracts were identified by searching the EMBASE database and manually searching abstracts from relevant congresses.

RESULTS

A total of 113 journal articles and 149 abstracts were found. Of these, 70 were considered relevant and included in this analysis. Most of the publications were uncontrolled, observational studies. Data from six randomised, controlled trials were identified. In general, the evidence revealed no clinically important efficacy or safety signals associated with switching.

CONCLUSIONS

While available data have not identified significant risks associated with a single switch between reference and biosimilar infliximab, the studies available currently report on only single switches and were mostly observational studies lacking control arms. Additional data are needed to explore potential switching risks in various populations and scenarios.

PP087. Deep trial secondary analysis: Digoxin immune fab fragment treatment has additional benefits in endogenous digitalis-like factor positive preeclamptic women

INTRODUCTION

A double blinded placebo controlled clinical trial of a commercial digoxin immune Fab fragment (DIF) in preeclamptic (PE) women provided some benefit to treated subjects (1). In that study DIF, relative to placebo, prevented a decline in CrCl and lowered levels of endogenous digitalis-like factor (EDLF) activity as measured by sodium pump inhibition (SPI). However, some PE subjects had undetectable EDLF.

OBJECTIVES

The hypothesis tested was that only PE women with measureable EDLF would respond to DIF treatment and analysis of EDLF positive women might reveal treatment effects masked by inclusion of EDLF negative, and hence non-responding, PE women. Accordingly, analyses of DIF effects in EDLF positive PE women were conducted.

METHODS

Patient characteristics and study design have been published (1). In these subanalyses, subjects were considered to be EDLF positive if their plasma inhibited red cell sodium pump mediated Rb uptake. All analyses were redone for the EDLF positive subgroup by Covance Inc as in the original trial. Continuous data were analyzed by ANCOVA. Categorical data were analyzed by Barnard Exact Test.

RESULTS

45 subjects (23 DIF, 22 placebo) had baseline SPI evaluated. Of these 22% had undetectable SPI. EDLF positive PE women showed greater and more significant reductions of SPI in response to DIF at each time point (12, 24, 48 hr treatment) than in the original analysis. Subjects with undetectable EDLF showed no significant change in response to DIF or placebo. For CrCl, EDLF positive PE women showed greater and more significant preservation of CrCl compared with original analyses. Subjects absent EDLF showed deterioration of CrCl with or without DIF. Among EDLF positive PE women DIF treated women had significantly less maternal pulmonary edema (p=0.035) and significantly less intraventricular hemorrhage in their infants (p=0.015). There was the suggestion of reductions in the incidence of other maternal and neonatal abnormalities.

CONCLUSION

These data indicate that EDLF positive PE women are those that responded to DIF and also raise the possibility of extended benefits of DIF treatment in this group. Results support further research in this area.

Integrated equation to evaluate accumulation profiles of drugs eliminated by Michaelis-Menten kinetics

Using an equation for the calculation of plasma profiles of drug based on the zero-order input and Michaelis-Menten kinetic output in a one-compartment open model system, the times required to reach various degrees of several steady-state plasma concentrations of phenytoin are calculated. The effect of the apparent volume of distribution (due to intersubject variation or change in protein and/or tissue binding, etc.) on the time required to reach various fractions of steady-state plasma concentrations is discussed.

Coronary arterial calcification in rheumatoid arthritis: comparison with the Multi-Ethnic Study of Atherosclerosis

Introduction

Although cardiovascular morbidity and mortality are increased in rheumatoid arthritis, little is known about the burden of subclinical coronary atherosclerosis in these patients.

Methods

Using computed tomography, coronary artery calcification was measured in 195 men and women with rheumatoid arthritis aged 45 to 84 years without clinical cardiovascular disease and compared with 1,073 controls without rheumatoid arthritis enrolled in the Baltimore cohort of the Multi-Ethnic Study of Atherosclerosis.

Results

The prevalence of coronary calcification (Agatston score > 0) was significantly higher in men, but not women, with rheumatoid arthritis after adjusting for sociodemographic and cardiovascular risk factors (prevalence ratio = 1.19; P = 0.012). Among participants with prevalent calcification, those with rheumatoid arthritis had adjusted mean Agatston scores 53 units higher than controls (P = 0.002); a difference greater for men than women (P for interaction = 0.017). In all analyses, serum IL-6 attenuated the association between rheumatoid arthritis and coronary calcification, suggesting its role as a potential mediator of enhanced atherosclerosis. Notably, increasing severity of rheumatoid arthritis was associated with a higher prevalence and extent of coronary calcification among both men and women with rheumatoid arthritis, and for all age categories. The largest percentage difference in coronary arterial calcification between rheumatoid arthritis patients and their nonrheumatoid arthritis counterparts was observed in the youngest age category.

Conclusions

Increasing rheumatoid arthritis disease severity was associated with a higher prevalence and greater extent of coronary artery calcification, potentially mediated through an atherogenic effect of chronic systemic inflammation. Gender and age differences in association with coronary calcification suggest that preventive measures should be emphasized in men with rheumatoid arthritis, and considered even in younger rheumatoid arthritis patients with low levels of traditional cardiovascular risk factors.

Banoxantrone (AQ4N), tissue CYP 450 targeted prodrug: The results of a phase I study using an accelerated dose escalation

2011

Background: AQ4N was rationally designed to have anti-tumor activity following bioreduction by tissue cytochrome P450 to AQ4, an active DNA topoisomerase II inhibitor. Preclinical studies demonstrated AQ4N selectively targets lymphoid tissues and hypoxic tumor tissues. This study assessed the maximum tolerated dose (MTD), pharmacokinetic (PK), and pharmacodynamic (PD) of repeated weekly dosing of AQ4N in patients (pts) with advanced cancers. Methods: AQ4N was administered IV on Days 1, 8, and 15 of a 28-day cycle in the following dose cohorts 12, 24, 48, 96, 192, 384, 768, and 1200 mg/m2. Accelerated titration design 2B was employed and the MTD was defined by ≤ 33% of 6 pts with a drug-related dose limiting toxicity (DLT). Response was assessed every 8 weeks by RECIST. Results: 16 pts were enrolled. A single pt per cohort was treated up to 384 mg/m2. At 1200 mg/m2, 2 of 5 pts experienced a DLT (Grade 5 respiratory distress and Grade 3 fatigue). A total of 5 pts were treated without toxicity at the 768 mg/m2, and established this dose as MTD. One pt in the 1200 mg/m2 cohort died during the trial from acute complications of metastatic soft tissue sarcoma and respiratory distress. The most common adverse events (AE) observed were fatigue (63%), anorexia (38%), nausea (38%), vomiting (38%), peripheral edema (25%), and diarrhea (25%). 6 pts experienced 8 serious AEs. Anticipated blue coloration of skin and body fluids was observed. One pt (48 mg/m2) with renal cancer has had stable disease for > 12 months. The PK was linear over all doses studied. At 768 mg/m2 (n=4), the Day 1 AQ4N Cmax was 99.8 ± 27.0 μg/mL, AUC0-∞ was 259.5 ± 67.8 μg·h/mL, and T1/2 was 3.9 ± 0.7 h (range 3.1–4.8 h). A predictable dose-related and exposure related decrease in lymphocytes and neutrophils were observed. Conclusions: AQ4N is well tolerated when administered on a weekly schedule. AQ4N levels sufficient for anti-neoplastic activity in pre-clinical models are achieved with weekly dosing at 768 mg/m2. AQ4N monotherapy and combination trials with chemo- and radiation therapy are planned.

[Table: see text]

Plasma leptin in men and women with seasonal affective disorder and in healthy matched controls

Seasonal affective disorder (SAD) is a specific clinical entity characterized by recurrent episodes of depression, which typically occur during the winter with periods of remission during the spring and summer. These depression episodes are accompanied by hyperphagia with cravings for carbohydrates and moderate weight gain, and usually respond to light therapy. We examined potential relationships between leptin, a hormone known to affect appetite and weight regulation, and seasonal changes in mood and appetite by measuring plasma leptin, clinical severity of depression, appetite scores, and body mass index (BMI) in 19 women and 8 men with SAD and matched controls (20 women and 8 men) in the summer and winter. Plasma leptin was positively correlated with BMI in patients and controls during both seasons. Women and men with SAD both experienced depression in the winter, which was associated with increased appetite, caloric intake, and carbohydrate craving. Increased body weight during the winter in subjects with SAD was paralleled by a lack of concomitant changes in plasma leptin, which suggests that leptin sensitivity to changes in body weight may be influenced by seasons in subjects with SAD, similar to seasonal mammals.

Suitability of using multileaf collimator (MLC) for photon field matching

This study evaluated and presented the results on the suitability of using a Siemens double-focused multileaf collimator (MLC) for photon field matching. The study was conducted using film-based dosimetry for measurements and a Theraplan Plus (version 3.8) treatment planning system (TPS) for planning comparisons and additional field matching investigations. In this study, it was found that the double-focused MLC field matching closely resembled that of the independent jaws, with the exception that the MLC had a nonuniform match line-a--match line formed by a different size leaf pair gap--overlap at a different join-up position. In addition, it was found that the dose change varied linearly with the MLC leaf pair gap-overlap (from 3-mm gap to 3-mm overlap) by 11 +/- 1%/mm. Using intrafraction "feathering" of the junction, a reduction of the dose change from 11 +/- 1%/mm to 6.5 +/- 1%/mm occurred when the junction was moved once and from 11 +/- 1%/mm to 4 +/- 1%/mm when moved twice. Based on the results, the study suggested that MLC positioning error tolerances of +/-2 mm might be too large for photon field matching. On the other hand, a combination of reducing the tolerance to +/-1 mm and intrafraction junction moves (twice by +/-1 cm off matching axis) could reduce the maximum peak height--trough low at the junction to within a required range of -5 to +7% in planning target volume (PTV) dose heterogeneity.

Leydig cell tumour--a rare testicular tumour

Although Leydig cell tumour is a rare tumour which constitutes only 1-3% of all testicular tumours, still it is in the focus of interest because of the difficulties in determining its exact nature and subsequently the type of treatment and follow-up. We report a case of Leydig cell tumour with a review of the related literature.

Inducible expression of double-stranded RNA directs specific genetic interference in Drosophila

BACKGROUND

The introduction of double-stranded RNA (dsRNA) can selectively interfere with gene expression in a wide variety of organisms, providing an ideal approach for functional genomics. Although this method has been used in Drosophila, it has been limited to studies of embryonic gene function. Only inefficient effects have been seen at later stages of development.

RESULTS

When expressed under the control of a heat-inducible promoter, dsRNA interfered efficiently and specifically with gene expression during larval and prepupal development in Drosophila. Expression of dsRNA corresponding to the EcR ecdysone receptor gene generated defects in larval molting and metamorphosis, resulting in animals that failed to pupariate or prepupae that died with defects in larval tissue cell death and adult leg formation. In contrast, expression of dsRNA corresponding to the coding region of the betaFTZ-F1 orphan nuclear receptor had no effect on puparium formation, but led to an arrest of prepupal development, generating more severe lethal phenotypes than those seen with a weak betaFTZ-F1 loss-of-function allele. Animals that expressed either EcR or betaFTZ-F1 dsRNA showed defects in the expression of corresponding target genes, indicating that the observed developmental defects are caused by disruption of the genetic cascades that control the onset of metamorphosis.

CONCLUSIONS

These results confirm and extend our understanding of EcR and betaFTZ-F1 function. They also demonstrate that dsRNA expression can inactivate Drosophila gene function at later stages of development, providing a new tool for functional genomic studies in Drosophila.

Arsenic trioxide induces dose- and time-dependent apoptosis of endothelium and may exert an antileukemic effect via inhibition of angiogenesis

Arsenic trioxide (As(2)O(3)) has recently been used successfully in the treatment of acute promyelocytic leukemia and has been shown to induce partial differentiation and apoptosis of leukemic cells in vitro. However, the mechanism by which As(2)O(3) exerts its antileukemic effect remains uncertain. Emerging data suggest that the endothelium and angiogenesis play a seminal role in the proliferation of liquid tumors, such as leukemia. We have shown that activated endothelial cells release cytokines that may stimulate leukemic cell growth. Leukemic cells, in turn, can release endothelial growth factors, such as vascular endothelial growth factor (VEGF). On the basis of these observations, we hypothesized that As(2)O(3) may interrupt a reciprocal loop between leukemic cells and the endothelium by direct action on both cell types. We have shown that treatment of proliferating layers of human umbilical vein endothelial cells (HUVECs) with a variety of concentrations of As(2)O(3) results in a reproducible dose- and time-dependent sequence of events marked by change to an activated morphology, up-regulation of endothelial cell adhesion markers, and apoptosis. Also, treatment with As(2)O(3) caused inhibition of VEGF production in the leukemic cell line HEL. Finally, incubation of HUVECs with As(2)O(3) prevented capillary tubule and branch formation in an in vitro endothelial cell-differentiation assay. In conclusion, we believe that As(2)O(3 )interrupts a reciprocal stimulatory loop between leukemic cells and endothelial cells by causing apoptosis of both cell types and by inhibiting leukemic cell VEGF production. (Blood. 2000;96:1525-1530)

E93 directs steroid-triggered programmed cell death in Drosophila

Steroid hormones coordinate multiple cellular changes, yet the mechanisms by which these systemic signals are refined into stage- and tissue-specific responses remain poorly understood. Here we show that the Drosophila E93 gene determines the nature of a steroid-induced biological response. E93 mutants possess larval salivary glands that fail to undergo steroid-triggered programmed cell death, and E93 is expressed in cells immediately before the onset of death. E93 protein is bound to the sites of steroid-regulated and cell death genes on polytene chromosomes, and the expression of these genes is defective in E93 mutants. Furthermore, expression of E93 is sufficient to induce programmed cell death. We propose that the steroid induction of E93 determines a programmed cell death response during development.

Stromal derived factor-1-induced chemokinesis of cord blood CD34(+) cells (long-term culture-initiating cells) through endothelial cells is mediated by E-selectin

Homing of hematopoietic stem cells to the bone marrow (BM) involves sequential interaction with adhesion molecules expressed on BM endothelium (BMEC) and chemokine stromal derived factor-1 (SDF-1). However, the mechanism whereby adhesion molecules regulate the SDF-1-induced transendothelial migration process is not known. E-selectin is an endothelial-specific selectin that is constitutively expressed by the BMEC in vivo. Hence, we hypothesized that E-selectin may mediate SDF-1-induced transendothelial migration of CD34(+) cells. We show that CD34(+) cells express both E-selectin ligand and fucosyltransferase-VII (FucT-VII). Soluble E-selectin-IgG chimera binds avidly to 75% +/- 10% of CD34(+) cells composed mostly of progenitors and cells with long-term culture-initiating cell (LTC-IC) potential. To assess the functional capacity of E-selectin to mediate CD34(+) cell migration in a transendothelial migration system, CD34(+) cells were placed on transwell plates coated with interleukin-1beta-activated BMEC. In the absence of SDF-1, there was spontaneous migration of 7.0% +/- 1.4% of CD34(+) cells and 14.1% +/- 2.2% of LTC-IC. SDF-1 induced migration of an additional 23.0% +/- 4.4% of CD34(+) cells and 17.6% +/- 3.6% of LTC-IC. Blocking MoAb to E-selectin inhibited SDF-1-induced migration of CD34(+) cells by 42.0% +/- 2.5% and LTC-IC by 90.9% +/- 16.6%. To define the mechanism of constitutive expression of E-selectin by the BMEC in vivo, we have found that vascular endothelial growth factor (VEGF(165)) induces E-selectin expression by cultured endothelial cells. VEGF-stimulated endothelial cells support transendothelial migration of CD34(+) cells that could be blocked by MoAb to E-selectin. These results suggest that trafficking of subsets of CD34(+) cells with LTC-IC potential is determined in part by sequential interactions with E-selectin and SDF-1.

DHR3 is required for the prepupal-pupal transition and differentiation of adult structures during Drosophila metamorphosis

Pulses of the steroid hormone ecdysone activate genetic regulatory hierarchies that coordinate the developmental changes associated with Drosophila metamorphosis. A high-titer ecdysone pulse at the end of larval development triggers puparium formation and induces expression of the DHR3 orphan nuclear receptor. Here we use both a heat-inducible DHR3 rescue construct and clonal analysis to define DHR3 functions during metamorphosis. Clonal analysis reveals requirements for DHR3 in the development of adult bristles, wings, and cuticle, and no apparent function in eye or leg development. DHR3 mutants rescued to the third larval instar also reveal essential functions during the onset of metamorphosis, leading to lethality during prepupal and early pupal stages. The phenotypes associated with these lethal phases are consistent with the effects of DHR3 mutations on ecdysone-regulated gene expression. Although DHR3 has been shown to be sufficient for early gene repression at puparium formation, it is not necessary for this response, indicating that other negative regulators may contribute to this pathway. In contrast, DHR3 is required for maximal expression of the midprepupal regulatory genes, EcR, E74B, and betaFTZ-1. Reductions in EcR and betaFTZ-F1 expression, in turn, lead to submaximal early gene induction in response to the prepupal ecdysone pulse and corresponding defects in adult head eversion and salivary gland cell death. These studies demonstrate that DHR3 is an essential regulator of the betaFTZ-F1 midprepupal competence factor, providing a functional link between the late larval and prepupal responses to ecdysone. Induction of DHR3 in early prepupae ensures that responses to the prepupal ecdysone pulse will be distinct from responses to the late larval pulse and thus that the animal progresses in an appropriate manner through the early stages of metamorphosis.

Design and synthesis of isoxazoline derivatives as factor Xa inhibitors. 2

Intravascular clot formation is an important factor in a number of cardiovascular diseases. Therefore, the prevention of blood coagulation has become a major target for new therapeutic agents. One attractive approach is the inhibition of factor Xa (FXa), the enzyme directly responsible for thrombin activation. Herein we report a series of isoxazoline derivatives which are potent FXa inhibitors. Optimization of the side chain at the quaternary position of the isoxazoline ring led to SK549 which showed subnanomolar FXa potency (K(i) 0.52 nM). SK549 shows good selectivity for FXa compared to thrombin and trypsin, potent antithrombotic effect in the rabbit arterio-venous thrombosis model, and improved pharmacokinetics relative to other compounds evaluated from this series.

Syndrome of microcephaly, microphthalmia, cataracts, and intracranial calcification

We present two sisters with microcephaly, developmental delay, marked microphthalmia, congenital cataracts, cerebral and cerebellar hypoplasia, and intracranial calcification. No evidence of intrauterine infection was found. There have been previous reports of microcephaly, intracranial calcification, and an intrauterine infection-like autosomal recessive condition, but the sibs in this report appear to represent a more severe form of such a condition or a previously undescribed entity.

Gender differences in glycosylated hemoglobin levels in seasonal affective disorder patients and controls

Seasonal affective disorder (SAD) has been shown to manifest different symptoms in female and male patients. Specifically, women with SAD have been shown to have greater increases in overeating, weight gain, and increased sleep as compared with their male counterparts. Given these dietary changes, we predicted that female SAD patients would exhibit increased glycosylated hemoglobin (HbA1) levels, indicative of chronically elevated glucose levels. Twenty-two patients (15 women and seven men) and matched controls were enrolled during the winter season and tested for HbA1 levels. A three-way analysis of variance (ANOVA; gender x group x season) was insignificant and the result was a negative study. After the initial hypothesis was rejected, we undertook a post-hoc analysis of the data, from which emerged that in winter, women patients had higher HbA1 levels as compared with matched controls. As our original hypothesis was rejected, we cannot accept the results of the post-hoc study. However, numerous other studies have demonstrated that female and male SAD patients differ in their pathophysiology, and are suggestive that in future analyses ought to consider analyzing subjects separately across gender.

Characterization of multiple cysteine and cystine transporters in rat alveolar type II cells

Cysteine availability is rate limiting for the synthesis of glutathione, an important antioxidant in the lung. We used rat alveolar epithelial type II cells to study the mechanism of cysteine and cystine uptake. Consistent with carrier-mediated transport, each uptake process was saturable with Michaelis-Menten kinetics and was inhibited at 4 degrees C and by micromolar levels of amino acids or analogs known to be substrates for a specific transporter. A unique system XAG was found that transports cysteine and cystine (as well as glutamate and aspartate, the only substrates previously described for system XAG). We also identified a second Na(+)-dependent cysteine transporter system, system ASC, and two Na(+)-independent transporter systems, system xc for cystine and system L for cysteine. In the presence of glutathione at levels measured in rat plasma and alveolar lining fluid, cystine was reduced to cysteine and was transported on systems ASC and XAG, doubling the transport rate. Cysteinylglycine, released from glutathione at the cell surface by gamma-glutamyl transpeptidase, also stimulated uptake after reduction of cystine. These findings suggest that, under physiological conditions, cysteine and cystine transport is influenced by the extracellular redox state.

Kidney allograft with a lymphocytic infiltrate: acute rejection, posttransplantation lymphoproliferative disorder, neither, or both entities?

The two cases presented illustrate the diagnostic difficulties and recommend an approach to use in patients in whom features of acute renal allograft rejection and posttransplant lymphoproliferative disorder (PTLD) appear simultaneously in allograft biopsies. Both patients developed acute allograft rejection episodes in the early post-transplant period followed by severe immunosuppression (OKT-3) and active Epstein-Barr virus infection. In addition to early recognition of light microscopic features of PTLD, immunohistology and in situ hybridization for EBV complement the diagnostic work-up and provide clues to the prompt diagnosis of rapidly developing PTLD affecting the allograft even in the face of persisting rejection.

Inherited resistance to HIV-1 conferred by an inactivating mutation in CC chemokine receptor 5: studies in populations with contrasting clinical phenotypes, defined racial background, and quantified risk

BACKGROUND

CC chemokine receptor 5 (CCR5) is a cell entry cofactor for macrophage-tropic isolates of human immunodeficiency virus-1 (HIV-1). Recently, an inactive CCR5 allele (designated here as CCR5-2) was identified that confers resistance to HIV-1 infection in homozygotes and slows the rate of progression to AIDS in heterozygotes. The reports conflict on the effect of heterozygous CCR5-2 on HIV-1 susceptibility, and race and risk levels have not yet been fully analyzed. Here we report our independent identification of CCR5-2 and test its effects on HIV-1 pathogenesis in individuals with contrasting clinical outcomes, defined race, and quantified risk.

MATERIALS AND METHODS

Mutant CCR5 alleles were sought by directed heteroduplex analysis of genomic DNA from random blood donors. Genotypic frequencies were then determined in (1) random blood donors from North America, Asia, and Africa; (2) HIV-1+ individuals; and (3) highly exposed-seronegative homosexuals with quantified risk.

RESULTS

CCR5-2 was the only mutant allele found. It was common in Caucasians, less common in other North American racial groups, and not detected in West Africans or Tamil Indians. Homozygous CCR5-2 frequencies differed reciprocally in highly exposed-seronegative (4.5%, n = 111) and HIV-1-seropositive (0%, n = 614) Caucasians relative to Caucasian random blood donors (0.8%, n = 387). This difference was highly significant (p < 0.0001). By contrast, heterozygous CCR5-2 frequencies did not differ significantly in the same three groups (21.6, 22.6, and 21.7%, respectively). A 55% increase in the frequency of heterozygous CCR5-2 was observed in both of two cohorts of Caucasian homosexual male, long-term nonprogressors compared with other HIV-1+ Caucasian homosexuals (p = 0.006) and compared with Caucasian random blood donors. Moreover, Kaplan-Meier estimates indicated that CCR5-2 heterozygous seroconvertors had a 52.6% lower risk of developing AIDS than homozygous wild-type seroconvertors.

CONCLUSIONS

The data suggest that homozygous CCR5-2 is an HIV-1 resistance factor in Caucasians with complete penetrance, and that heterozygous CCR5-2 slows the rate of disease progression in infected Caucasian homosexuals. Since the majority (approximately 96%) of highly exposed-seronegative individuals tested are not homozygous for CCR5-2, other resistance factors must exist. Since CCR5-2 homozygotes have no obvious clinical problems, CCR5 may be a good target for the development of novel antiretroviral therapy.

Proton dosimetry intercomparison

BACKGROUND AND PURPOSE

Methods for determining absorbed dose in clinical proton beams are based on dosimetry protocols provided by the AAPM and the ECHED. Both groups recommend the use of air-filled ionization chambers calibrated in terms of exposure or air kerma in a 60Co beam when a calorimeter or Faraday cup dosimeter is not available. The set of input data used in the AAPM and the ECHED protocols, especially proton stopping powers and w-value is different. In order to verify inter-institutional uniformity of proton beam calibration, the AAPM and the ECHED recommend periodic dosimetry intercomparisons. In this paper we report the results of an international proton dosimetry intercomparison which was held at Loma Linda University Medical Center. The goal of the intercomparison was two-fold: first, to estimate the consistency of absorbed dose delivered to patients among the participating facilities, and second, to evaluate the differences in absorbed dose determination due to differences in 60Co-based ionization chamber calibration protocols.

MATERIALS AND METHODS

Thirteen institutions participated in an international proton dosimetry intercomparison. The measurements were performed in a 15-cm square field at a depth of 10 cm in both an unmodulated beam (nominal accelerator energy of 250 MeV) and a 6-cm modulated beam (nominal accelerator energy of 155 MeV), and also in a circular field of diameter 2.6 cm at a depth of 1.14 cm in a beam with 2.4 cm modulation (nominal accelerator energy of 100 MeV).

RESULTS

The results of the intercomparison have shown that using ionization chambers with 60Co calibration factors traceable to standard laboratories, and institution-specific conversion factors and dose protocols, the absorbed dose specified to the patient would fall within 3% of the mean value. A single measurement using an ionization chamber with a proton chamber factor determined with a Faraday cup calibration differed from the mean by 8%.

CONCLUSION

The adoption of a single ionization chamber dosimetry protocol and uniform conversion factors will establish agreement on proton absorbed dose to approximately 1.5%, consistent with that which has been observed in high-energy photon and electron dosimetry.

Combination therapy of single or fractionated x-rays and schizophyllan (spg) for murine B-16 melanoma

B-16 melanoma transplanted into C57BL/6 mice was used to investigate the antitumor effect of Schizophyllan (SPG) combination with local irradiation by X-rays using 4 fractions of 3 Gy or 9 Gy and single fractions of 12, 19 and 26 Gy. In the groups which received a single fraction of 26 Gy and 4 fractions of 9 Gy, significant differences were found between the groups with/without SPG in terms of tumor volume change and lymph node and pulmonary metastases. In terms of survival, significant difference was found only in the 4 fraction of the 9 Gy group. SPG had no antitumor effect nor life-prolonging effect, when it was applied to tumors irradiated with single fractions of 12 and 19 Gy or 4 fractions of 3 Gy, except for some metastasis-suppressing effect in the group given 19 Gy. It seems that SPG has some adjuvant effect only where a limited number of tumor cells remain following rather large dose of X-irradiation. Furthermore, the gain produced by host-mediated immune response augmented by SPG seems to be larger in the 4 fraction group. Therefore, combination radiotherapy using SPG may be advantageous for patients with complete response or a good response after multifractionated irradiation.

Combination therapy with pions and schizophyllan (spg) for murine B-16 melanoma

The B-16 melanoma transplanted into C57BL/6 mice was used to investigate the antitumor effect of Schizophyllan (SPG) when applied alone and in combination with local irradiation using pions with 4 dose fractions of 2 Gy or 6 Gy each. SPG was given intramuscularly in a daily dose of 10 mg/kg body weight for 25 consecutive days from day 4 after the initiation of irradiation, and thereafter three times a week up to day 45. The antitumor effect was evaluated by the changes in tumor volume. survival, the size of metastatic lymph nodes grossly involved, and the number of pulmonary metastatic nodules on the surface of the lungs. After 24 Gy, significant differences were found between the group treated with combined pions and SPG, and the group treated with pions alone in terms of tumor volume change. survival and lymph node, and pulmonary metastases. However, when SPG was applied to non-irradiated tumors or to tumors irradiated with only 8 Gy, it had neither antitumor nor life-prolonging effect. From the present study, it seems that a SPG, as a Biological Response Modifier, has some adjuvant effect only where a limited number of tumor cells remain following pion irradiation. Combination therapy using SPG may, therefore, be advantageous for patients with complete response or good partial response to pion irradiation.

The correlation between rises in intracellular calcium and PGI2 production in cultured vascular endothelial cells

Elevation of intracellular calcium in response to trypsin, bradykinin, thrombin or histamine is associated with a proportional increase in PGI2 production in cultured human umbilical vein endothelial cells (HUVEC), bovine pulmonary artery endothelial cells (CPAE), and bovine aortic endothelial cells (BAEC). The major agonists that induce increases in intracellular calcium and PGI2 production are thrombin and trypsin in HUVEC, bradykinin in CPAE, and bradykinin and trypsin in BAEC. These results suggest that endothelial cells derived from different species or sites require different agonists to induce increases in intracellular calcium and PGI2 production and that only agonists which increase intracellular calcium can stimulate PGI2 production.

Lipopolysaccharides decrease angiotensin converting enzyme activity expressed by cultured human endothelial cells

Angiotensin converting enzyme (ACE) is present on endothelial cells and plays a role in regulating blood pressure in vivo by converting angiotensin I to angiotensin II and metabolizing bradykinin. Since ACE activity is decreased in vivo in sepsis, the ability of lipopolysaccharide (LPS) to suppress endothelial cell ACE activity was tested by culturing human umbilical vein endothelial cells (HUVEC) for 0-72 hr with or without LPS and then measuring ACE activity. ACE activity in intact HUVEC monolayers incubated with LPS (10 micrograms/ml) decreased markedly with time and was inhibited by 33%, 71%, and 76% after 24 hr, 48 hr, and 72 hr, respectively, when compared with control, untreated cells. The inhibitory effect of LPS was partially reversible upon removal of the LPS and further incubation in the absence of LPS. The LPS-induced decrease in ACE activity was dependent on the concentrations of LPS (IC50 = 15 ng/ml at 24 hr) and was detectable at LPS concentrations as low as 1 ng/ml. That LPS decreased the Vmax of ACE in the absence of cytotoxicity and without a change in Km suggests that LPS decreased the amount of ACE present on the HUVEC cell membrane. While some LPS serotypes (Escherichia coli 0111:B4 and 055:B5, S. minnesota) were more potent inhibitors of ACE activity than others (E. coli 026:B6 and S. marcescens), all LPS serotypes tested were inhibitory. These finding suggest that LPS decreases endothelial ACE activity in septic patients; in turn, this decrease in ACE activity may decrease angiotensin II production and bradykinin catabolism and thus play a role in the pathogenesis of septic shock.

IFN-gamma and IFN-alpha induce the expression and synthesis of Leu 13 antigen by cultured human endothelial cells

Leu 13 is a 16 kDa human lymphocyte surface Ag and monoclonal anti-Leu 13 induces T cell aggregation and alters T cell proliferation. In previous studies using anti-Leu 13, Leu 13 Ag has been detected on endothelial cells (EC) of arteries, capillaries, and veins in human tissue sections. In contrast, in this study using the same antibody, Leu 13 Ag could not be detected on unstimulated cultured human umbilical vein endothelial cells (HUVEC) by indirect immunofluorescence, immunoperoxidase staining, or immunoisolation of radiolabeled Ag from labeled endothelial cells. However, when HUVEC were cultured with IFN-gamma, Leu 13 Ag was demonstrable using all three detection techniques. Leu 13 Ag was detectable after 24 h of incubation with IFN-gamma (30 U/ml) and was maximally expressed after 72 h. After removal of IFN-gamma, Leu 13 Ag progressively declined back to basal levels by 4 days. Induction of Leu 13 Ag expression by IFN-gamma was suppressed by cycloheximide. Although Leu 13 Ag expression was also induced by IFN-alpha, PMA, and IL-1 were inactive. When HUVEC were incubated with IFN-gamma, surface-labeled with 125I, and then solubilized, anti-Leu 13 immunoisolated a 16-kDa radioactive band that comigrated with Leu 13 immunoisolated from T cells. Similar results were obtained using HUVEC that were metabolically labeled with 35S-methionine. These results demonstrate that HUVEC stimulated with IFN-gamma and IFN-alpha express Leu 13 Ag on their surface and suggest that exposure of EC to IFN may induce EC to develop new functional properties at sites of inflammatory and immune reactions.

IFN-gamma and IFN-alpha induce the expression and synthesis of Leu 13 antigen by cultured human endothelial cells

Leu 13 is a 16 kDa human lymphocyte surface Ag and monoclonal anti-Leu 13 induces T cell aggregation and alters T cell proliferation. In previous studies using anti-Leu 13, Leu 13 Ag has been detected on endothelial cells (EC) of arteries, capillaries, and veins in human tissue sections. In contrast, in this study using the same antibody, Leu 13 Ag could not be detected on unstimulated cultured human umbilical vein endothelial cells (HUVEC) by indirect immunofluorescence, immunoperoxidase staining, or immunoisolation of radiolabeled Ag from labeled endothelial cells. However, when HUVEC were cultured with IFN-gamma, Leu 13 Ag was demonstrable using all three detection techniques. Leu 13 Ag was detectable after 24 h of incubation with IFN-gamma (30 U/ml) and was maximally expressed after 72 h. After removal of IFN-gamma, Leu 13 Ag progressively declined back to basal levels by 4 days. Induction of Leu 13 Ag expression by IFN-gamma was suppressed by cycloheximide. Although Leu 13 Ag expression was also induced by IFN-alpha, PMA, and IL-1 were inactive. When HUVEC were incubated with IFN-gamma, surface-labeled with 125I, and then solubilized, anti-Leu 13 immunoisolated a 16-kDa radioactive band that comigrated with Leu 13 immunoisolated from T cells. Similar results were obtained using HUVEC that were metabolically labeled with 35S-methionine. These results demonstrate that HUVEC stimulated with IFN-gamma and IFN-alpha express Leu 13 Ag on their surface and suggest that exposure of EC to IFN may induce EC to develop new functional properties at sites of inflammatory and immune reactions.

Gene mapping by enzymatic amplification from flow-sorted chromosomes

A new approach to gene mapping which combines enzymatic amplification with high-resolution flow sorting of human chromosomes has been devised. Reliable amplification from as few as 200 chromosomes has been demonstrated. This method, with particular application to mapping the position of chromosomal translocations, has been used to show that the breakpoint for the constitutional translocation t(11;22)(q23;q11) lies proximal to the genes c-ets-1, Thy-1, and T3 delta and distal to the int-2 gene. The mapping was confirmed by Southern analysis to much larger numbers of chromosomes sorted from the same cell line. Control reactions for the bcl-2 gene on chromosome 18 and the C alpha gene of the IGH locus on chromosome 14 demonstrated the discrimination which can be achieved.