Blockade of the PD-1/PD-L1 axis augments lysis of AML cells by the CD33/CD3 BiTE antibody construct AMG 330: reversing a T-cell-induced immune escape mechanism

Bispecific T-cell engagers (BiTEs) are very effective in recruiting and activating T cells. We tested the cytotoxicity of the CD33/CD3 BiTE antibody construct AMG 330 on primary acute myeloid leukemia (AML) cells ex vivo and characterized parameters contributing to antileukemic cytolytic activity. The E:T ratio and the CD33 expression level significantly influenced lysis kinetics in long-term cultures of primary AML cells (n=38). AMG 330 induced T-cell-mediated proinflammatory conditions, favoring the upregulation of immune checkpoints on target and effector cells. Although not constitutively expressed at the time of primary diagnosis (n=123), PD-L1 was strongly upregulated on primary AML cells upon AMG 330 addition to ex vivo cultures (n=27, P<0.0001). This phenomenon was cytokine-driven as the sole addition of interferon (IFN)-γ and tumor necrosis factor-α also induced expression. Through blockade of the PD-1/PD-L1 interaction, AMG 330-mediated lysis (n=9, P=0.03), T-cell proliferation (n=9, P=0.01) and IFN-γ secretion (n=8, P=0.008) were significantly enhanced. The combinatorial approach was most beneficial in settings of protracted AML cell lysis. Taken together, we have characterized a critical resistance mechanism employed by primary AML cells under AMG 330-mediated proinflammatory conditions. Our results support the evaluation of checkpoint molecules in upcoming clinical trials with AMG 330 to enhance BiTE antibody construct-mediated cytotoxicity.

2015 Update on Acute Adverse Reactions to Gadolinium based Contrast Agents in Cardiovascular MR. Large Multi-National and Multi-Ethnical Population Experience With 37788 Patients From the EuroCMR Registry

OBJECTIVES

Specifically we aim to demonstrate that the results of our earlier safety data hold true in this much larger multi-national and multi-ethnical population.

BACKGROUND

We sought to re-evaluate the frequency, manifestations, and severity of acute adverse reactions associated with administration of several gadolinium- based contrast agents during routine CMR on a European level.

METHODS

Multi-centre, multi-national, and multi-ethnical registry with consecutive enrolment of patients in 57 European centres.

RESULTS

During the current observation 37,788 doses of Gadolinium based contrast agent were administered to 37,788 patients. The mean dose was 24.7 ml (range 5-80 ml), which is equivalent to 0.123 mmol/kg (range 0.01 - 0.3 mmol/kg). Forty-five acute adverse reactions due to contrast administration occurred (0.12%). Most reactions were classified as mild (43 of 45) according to the American College of Radiology definition. The most frequent complaints following contrast administration were rashes and hives (15 of 45), followed by nausea (10 of 45) and flushes (10 of 45). The event rate ranged from 0.05% (linear non-ionic agent gadodiamide) to 0.42% (linear ionic agent gadobenate dimeglumine). Interestingly, we also found different event rates between the three main indications for CMR ranging from 0.05% (risk stratification in suspected CAD) to 0.22% (viability in known CAD).

CONCLUSIONS

The current data indicate that the results of the earlier safety data hold true in this much larger multi-national and multi-ethnical population. Thus, the "off-label" use of Gadolinium based contrast in cardiovascular MR should be regarded as safe concerning the frequency, manifestation and severity of acute events.

[Resident Gynaecologists' Attitudes towards the Inclusion of the Screening for Gestational Diabetes into the Maternity Directive: A Qualitative Study]

BACKGROUND

In March 2012, the screening for gestational diabetes was included as a 2-step screening into the German maternity directive. However, up to now it is unclear what resident gynaecologists, who are affected directly by this change in the maternity directive, think about the inclusion of the screening and the kind of screening introduced.

METHODS

In order to approach this topic from a scientific point of view, gynaecologists in the German cities Mannheim, Ludwigshafen, and Heidelberg were interviewed face-to-face using a semi-structured interview guide with open-ended questions (mean interview length: 33:12 min). The interviews were audiotaped, transcribed verbatim (191 pages), coded by 2 independent reviewers, and analysed using qualitative content analysis.

RESULTS

The majority of the gynaecologists supported the introduction of the screening into the maternity directives. However, some gynaecologists felt that this amendment is not strong enough criticising the GCT with 50 g glucose. Many gynaecologists would prefer an oral glucose tolerance test (OGTT, 75 g glucose). But there were also some gynaecologists who thought that the OGTT would strain pregnant women too much and thus deemed it unsuitable for a screening. Additionally, the gynaecologists named difficulties concerning the implementation of the test such as, for example, the non-availability of a ready-made glucose syrup for the GCT and the delayed introduction of billing codes.

DISCUSSION

In the framework of this qualitative study, resident gynaecologists--the main actors in the conduct of the screening--had the possibility to offer their opinion on this current topic. The results provide a first insight into the conduct of the screening and may serve as a basis for larger, quantitative studies.

Efficacy of sustained combination therapy for at least 6 months with thiopurines and infliximab in patients with ulcerative colitis in clinical remission: a retrospective multicenter French experience

BACKGROUND AND AIMS

Long-term benefits of combination therapy (combotherapy) with infliximab (IFX) and azathioprine (AZA) have been less studied in ulcerative colitis (UC) than in Crohn's disease. The aim of the present study was to determine UC disease activity in patients who received at least 6 months of combotherapy, and whether cotreatment for more than 6 months was useful in these patients.

METHODS

A retrospective multicenter study was conducted in seven French academic centers from January 2010 to September 2012, including all UC patients having received at least 6 months of combotherapy in prolonged remission off steroids. During the follow-up period, which was divided into trimesters, scheduled IFX was continued as maintenance and AZA could be withdrawn. Assessment of UC activity by trimester was based on the following events: disease relapse defined by clinical relapse requiring a change of treatment, IFX failure, and colectomy.

RESULTS

Eighty-two patients were included (mean age 38 years; male:female ratio 1:1) and followed up for a median of 22.3±14.0 months. Comparing 393 trimesters of combotherapy with 282 trimesters of IFX alone, fewer clinical relapses were observed with combotherapy (p = 0.049). Similar results were observed for IFX failure (p = 0.048). No difference was observed for colectomy. Duration of combotherapy longer than 9 months was inversely associated with clinical relapse (hazard ratio = 0.32 [95% confidence interval 0.15-0.70]).

CONCLUSIONS

UC patients treated with combotherapy should maintain IFX and AZA for at least 9 months. Further studies are required to determine the optimal duration of combotherapy before stopping AZA in this situation.

Cobalamin deficiency in the elderly: aetiology and management: a study of 125 patients in a geriatric hospital

INTRODUCTION

Cobalamin deficiency is frequent in elderly patients and the main aetiologies are food-cobalamin malabsorption and pernicious anaemia. The aim of our retrospective study was to identify the causes and methods of management of cobalamin deficiency at Nice geriatric university hospital.

METHODS

A retrospective monocentric study was conducted over 14 months at Nice geriatric hospital, which included patients with cobalamin deficiency having received supplementation. The clinical and paraclinical data, etiological diagnosis, treatment and follow-up modalities were analyzed retrospectively.

RESULTS

We studied 125 elderly patients whose median age was 85.5 ± 7 years. The etiological diagnosis was food-cobalamin malabsorption for 72 patients (57.6 %), nutritional cobalamin deficiency for 15 patients (12 %), pernicious anaemia for 12 patients (9.6 %) and there was no etiological diagnosis for 26 patients (20.8 %). Concerning cobalamin therapy, 111 patients (88.8 %) received oral therapy and 14 (11.2 %) intramuscular therapy. Vitamin B12 levels increased significantly after supplementation (p<0.001) but cobalamin administration varied according to the diagnoses (p<0.001) and was less effective in patients with dementia (p=0.04) and food-cobalamin malabsorption.

CONCLUSION

Our study showed the importance of food-cobalamin malabsorption in etiological diagnosis in accordance with the literature, but also the non-negligible share of nutritional cobalamin deficiency. Mainly oral cobalamin supplementation was used in our study with a significant increase in vitamin B12 levels. An oral cobalamin regimen is proposed for elderly patients with cobalamin deficiency but with no severe neurological signs.

Molecular profiling of myeloid progenitor cells in multi-mutated advanced systemic mastocytosis identifies KIT D816V as a distinct and late event

To explore the molecular profile and its prognostic implication in systemic mastocytosis (SM), we analyzed the mutation status of granulocyte-macrophage colony-forming progenitor cells (CFU-GM) in patients with KIT D816V(+) indolent SM (ISM, n=4), smoldering SM (SSM, n=2), aggressive SM (ASM, n=1), SM with associated clonal hematologic non-mast cell lineage disorder (SM-AHNMD, n=5) and ASM-AHNMD (n=7). All patients with (A)SM-AHNMD (n=12) carried 1-4 (median 3) additional mutations in 11 genes tested, most frequently TET2, SRSF2, ASXL1, CBL and EZH2. In multi-mutated (A)SM-AHNMD, KIT D816V(+) single-cell-derived CFU-GM colonies were identified in 8/12 patients (median 60%, range 0-95). Additional mutations were identified in CFU-GM colonies in all patients, and logical hierarchy analysis indicated that mutations in TET2, SRSF2 and ASXL1 preceded KIT D816V. In ISM/SSM, no additional mutations were detected and CFU-GM colonies were exclusively KIT D816V(-). These data indicate that (a) (A)SM-AHNMD is a multi-mutated neoplasm, (b) mutations in TET2, SRSF2 or ASXL1 precede KIT D816V in ASM-AHNMD,

How well are asthma treatment cards filled out in public health centres in Gazeera State, Sudan?

SETTING

Four public district hospitals offering asthma treatment in Gazeera State, Sudan. Incomplete recording of patient data directly affects the quality of asthma care and the evaluation of asthma management programmes.

OBJECTIVE

To assess the completeness of filling out of treatment cards and accuracy of calculating peak expiratory flow (PEF) for confirming diagnosis and grading severity of asthma.

DESIGN

Cross-sectional audit of asthma treatment cards from asthma centres, 2006-2012.

RESULTS

Of 959 patient cards assessed, completeness ranged from 47% to 98%. Six of 13 variables had an unsatisfactory grade of completeness (<80% complete). Calculated PEF was indicated in 885 (92%) cards, but was correct in only 609 (69%). PEF variability was recorded in 835 (87%) cards, but was correctly calculated in 442 (53%). A scheduled follow-up visit was attended by only 359 (37%) patients, indicating 63% loss to follow-up. Contact telephone numbers were missing from 453 (47%) cards.

CONCLUSION

This is the first study in Africa to assess the data completeness and integrity of asthma patient cards, identifying important shortcomings. This affects quality of management of asthma patients and programme evaluation. Steps to rectify this situation are urgently needed.

Prognostic role of FGFR1 amplification in early-stage non-small cell lung cancer

BACKGROUND

Recently, fibroblast growth factor receptor 1 (FGFR1) was discovered in squamous cell carcinomas (SCC) of the lung with FGFR1 amplification described as a promising predictive marker for anti-FGFR inhibitor treatment. Only few data are available regarding prevalence, prognostic significance and clinico-pathological characteristics of FGFR1-amplified and early-stage non-small cell lung carcinomas (NSCLC). We therefore investigated the FGFR1 gene status in a large number of well-characterised early-stage NSCLC.

METHODS

FGFR1 gene status was evaluated using a commercially available fluorescent in situ hybridisation (FISH) probe on a tissue microarray (TMA). This TMA harbours 329 resected, formalin-fixed and paraffin-embedded, nodal-negative NSCLC with a UICC stage I-II. The FISH results were correlated with clinico-pathological features and overall survival (OS).

RESULTS

The prevalence of an FGFR1 amplification was 12.5% (41/329) and was significantly (P<0.0001) higher in squamous cell carcinoma (SCC) (20.7%) than in adenocarcinoma (2.2%) and large cell carcinoma (13%). Multivariate analysis revealed significantly (P=0.0367) worse 5-year OS in patients with an FGFR1-amplified NSCLC.

CONCLUSIONS

FGFR1 amplification is common in early-stage SCC of the lung and is an independent and adverse prognostic marker. Its potential role as a predictive marker for targeted therapies or adjuvant treatment needs further investigation.

Circular Dichroism of Chromopeptides from Phycocyanin

The circular dichroism of bilipeptides from Spirulina geitleri phycocyanin is strongly solvent and pH dependent. Maximum optical activity has been observed in aqueous solutions containing urea (8 ᴍ). In aqueous buffer, a sign reversal occurred upon the change from neutral to acidic pH; in methanolic solutions shows the optical activity a strong pH dependence both with respect to sign and magnitude. These findings have been rationalized by the presence of chrom ophorepeptide interactions, which are minimized in the presence of urea. M olecular orbital calculations indicate that the observed sign reversal is not necessarily due to a reversal of the chirality of the entire chromophore, but may also result from more localized conform ational changes

Aldehyd-Dehydrogenase aus Leber, ein Enzym des Fructosestoffwechsels

1. Bei der 16 - 18-fachen Anreicherung der DPN-abhängigen Aldehyd-Dehydrogenase aus Rinderleber bleibt das Aktivitäts-Verhältnis des Enzyms mit Acetaldehyd und Glycerinaldehyd konstant.

2. Neben diesem Befund sprechen auch die Abhängigkeit der Dehydrierungs-Geschwindigkeit der beiden Aldehyde vom pH, das Ausmaß der Hemmung durch verschiedene Hemmstoffe und die Geschwindigkeit der Hydrierung von DPN bei einzelnem und gleichzeitigem Umsatz von Acetaldehyd und Glycerinaldehyd für eine Dehydrierung der beiden Aldehyde durch ein und dasselbe Enzym.

3. Da das Enzym D- und L-Glycerinaldehyd dehydriert und die Michaelis- Konstante mit Glycerinaldehyd 2,9 · 10-4 Mol/l beträgt, kann das gereinigte Enzym zur spektrophotometrischen Bestimmung von DL-Glycerinaldehyd benützt werden.

4. Wahrscheinlich ist das Enzym für den weiteren Umsatz des beim Fructoseabbau in der Leber anfallenden D-Glycerinaldehyds verantwortlich. Letzterer wird unter Beteiligung von DPN zu D-Glycerinsäure oxydiert, die dann in einer früher beschriebenen ATP-abhängigen Reaktion zu D-Phosphoglycerinsäure phosphoryliert wird und damit in den Abbauweg der Glykolyse einmündet.

Energy transfer within pc trimers of mastigocladus laminosus studied by picosecond time-resolved transient absorption spectroscopy

The transient absorption recovery induced in phycocyanin trimers by picosecond pulses of variable wavelength (570-620 nm) has been recorded and analyzed by applying a least-squares multi-exponential fit procedure.

The results suggest that in native PC trimers the chromophores exhibit a microheterogeneity with the effect that the derived apparent lifetimes are functions of excitation and probing wavelength. It is suggested that, due to strong excitonic coupling between a-84 and β-84 chromophores, the lifetime of the terminal acceptor state is reduced to about 900 ps; the apparent energy transfer time from chromophore β-155 to a-84 and β-84 chromophores varies between 20-50 ps depending on the actual chromophore-protein arrangement (microheterogeneity)

On the Influence of Intra - and Inter-Molecular Hydrogen Bonding on the Excited State Lifetime of Indigo Dyes

It is shown that intramolecular hydrogen bonding can give rise to very fast nonradiative desactivation of the S1 -state of indigo dyes. In those derivatives, which lack the possibility of internal hydrogen bonds, hydrogen bonding to suitable solvent molecules can provide the channel for fast radiationless transitions. As a consequence, drastic effects on the S1 -state lifetime are observed both as a function of solvent and/or temperature.

Split-bolus single-phase cardiac multidetector computed tomography for reliable detection of left atrial thrombus: comparison to transesophageal echocardiography

PURPOSE

Evaluation of a new cardiac MDCT protocol using a split-bolus contrast injection protocol and single MDCT scan for reliable diagnosis of LA/LAA thrombi in comparison to TEE, optimizing radiation exposure and use of contrast agent.

MATERIALS AND METHODS

A total of 182 consecutive patients with drug refractory AF scheduled for PVI (62.6 % male, mean age: 64.1 ± 10.2 years) underwent routine diagnostic work including TEE and cardiac MDCT for the evaluation of LA/LAA anatomy and thrombus formation between November 2010 and March 2012. Contrast media injection was split into a pre-bolus of 30 ml and main bolus of 70 ml iodinated contrast agent separated by a short time delay.

RESULTS

In this study, split-bolus cardiac MDCT identified 14 of 182 patients with filling defects of the LA/LAA. In all of these 14 patients, abnormalities were found in TEE. All 5 of the 14 patients with thrombus formation in cardiac MDCT were confirmed by TEE.

CONCLUSION

MDCT was 100 % accurate for thrombus, with strong but not perfect overall results for SEC equivalent on MDCT.

KEY POINTS

• Patients with no filling defect or thrombus in MDCT in the LA/LAA region are unlikely to have thrombus and may undergo PVI without TEE.• Here, the role of an additional TEE in pre-procedural management prior to PVI in patients with AF has to be redefined.• Using a split-bolus injection protocol increases the diagnostic accuracy of thrombus in the LA/LAA region.

Parental inconsistency, impulsive choice and neural value representations in healthy adolescents

A well-characterized potential marker for addiction is impulsive choice, stably measured by delay discounting (DD) paradigms. While genetic influences partly account for inter-individual variance in impulsivity, environmental factors such as parenting practices may have an important role. The present study investigates how inconsistent fulfillment of delayed reward promises impacts on DD. A combined correlational and experimental functional magnetic resonance imaging (fMRI) design was performed in a sample of 48 healthy adolescents (13-15 years). More specifically, neural activation during a DD task was investigated at two assessment points (T0 and T1). Adolescents' self-reports of parenting and substance use were assessed at T0. Between assessment points, we experimentally varied the reliability of delayed reward promises, measuring the impact of this intervention on DD and neural value processing at T1. In the correlational part, same-sex parent reward inconsistency was associated with steeper DD and an attenuated subjective value (SV) representation in the nucleus accumbens (NAcc) and ventromedial prefrontal cortex (vmPFC). Steeper DD was in turn associated with alcohol use during the past year. In the experimental part, the reward inconsistency manipulation resulted in an attenuation of the NAcc SV representation, similar to the parental inconsistency effect. Together, our correlational and experimental findings raise new light on how parents may influence their children's degree of impulsivity, making parenting a potential target in addiction prevention.

[Characteristics of 200 patients with suspected implant allergy compared to 100 symptom-free arthroplasty patients]

BACKGROUND

Data on implant allergies are incomplete; therefore, we compared the data on allergy history, patch test (PT) and lymphocyte transformation test (LTT) results in a patient series from the Munich implant allergy outpatient department with symptom-free arthroplasty patients.

PATIENTS AND METHODS

In this study 200 arthroplasty patients with complaints involving the prosthesis (130 female, 187 knee and 13 hip prostheses) and in parallel 100 symptom-free patients (75 female, 47 knee and 53 hip prostheses) were investigated. A questionnaire-aided history including implant type, cementing, intolerance of dental materials, atopy, cutaneous metal intolerance (CMI) and PT, including a standard series with Ni, Co, Cr, seven bone cement components, including gentamicin and benzoyl peroxide and LTT for Ni, Co and Cr.

RESULTS

In the knee arthroplasty patients with complaints 9.1% showed dental material intolerance, 23.5% atopy, 25.7% CMI, 18.2% metal allergies, 7.4% gentamicin allergy and 27.8% positive metal LTT (mostly to Ni). In symptom-free patients 0% showed dental material intolerance, 19.1% atopy, 12.8% CMI, 12.8% metal allergy, 0% gentamicin allergy and 17% positive metal LTT.

CONCLUSIONS

Characteristics of the patients with complaints were increased intolerance of dental materials, higher rates of atopy, CMI, metal and gentamicin allergy and LTT reactivity.

The effect of cilengitide in combination with irradiation and chemotherapy in head and neck squamous cell carcinoma cell lines

BACKGROUND

Integrins are highly attractive targets in oncology due to their involvement in angiogenesis in a wide spectrum of cancer entities. Among several integrin inhibitors under clinical evaluation, cilengitide is the most promising compound. However, little is known about the cellular processes induced during cilengitide therapy in combination with irradiation and cisplatin in head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

The cytostatic effect of cilengitide was assessed by proliferation assay in the three HNSCC cell lines SCC25, FaDu and CAL27. Combination experiments with cisplatin and irradiation were performed. Possible synergistic effects were calculated in combination index (CI) analyses. Colony forming inhibition was investigated in clonogenic assays. Real-time PCR arrays were used to evaluate target protein gene expression patterns. Flow cytometry was used to detect apoptosis.

RESULTS

Used alone, cilengitide has only minor cytotoxic effects in HNSCC cell lines. However, combination with cisplatin resulted in synergistic growth inhibition in all three cell lines. Irradiation showed synergism in short-term experiments and in colony forming assays, an additive effect was detected. Real-time PCR assay detected downregulation of the antiapoptotic protein Bcl-2 after exposure of cells to cilengitide.

CONCLUSION

Cilengitide in combination with cisplatin and irradiation may be a feasible option for the treatment of patients with head and neck cancer. However, further investigations are required to understand the exact mechanism that leads to synergistic cytotoxicity.

Stability against brushing abrasion and the erosion-protective effect of different fluoride compounds

This study aimed to analyse the impact of brushing on the protective effect of different fluoride solutions on enamel and dentin erosion. Bovine enamel and dentin specimens were rinsed once with TiF4, AmF, SnF2 (0.5 M F, 2 min) or water (control). Specimens were either left unbrushed or brushed with 10, 20, 50, 100 or 500 brushing strokes in an automatic brushing machine (2 N, non-fluoridated toothpaste slurry). Ten specimens per group were eroded with hydrochloric acid (HCl) (pH 2.3) for 60 s, and calcium release into the acid was determined by atomic absorption spectroscopy. Additionally, enamel and dentin surfaces were analysed by X-ray energy-dispersive spectroscopy (EDS) (n = 6/group) and scanning electron microscopy (SEM) (n = 2/group) before brushing and after 500 brushing strokes. Statistical analysis (p < 0.05) was performed by three- and one-way ANOVA (calcium release) or repeated measures ANOVA (EDS). TiF4, AmF and SnF2 reduced the erosive calcium loss in unbrushed specimens to 58-67% (enamel) and 23-31% (dentin) of control. Calcium release increased with increasing brushing strokes prior to erosion and amounted to 70-88% (enamel) and 45-78% (dentin) of control after 500 brushing strokes. Brushing reduced the surface concentration of fluoride (AmF), tin (SnF2) and titanium (TiF4). SEM revealed that surface precipitates were affected by long-term brushing. Brushing reduced the protective potential of TiF4, AmF and SnF2 solutions. However, considering a small number of brushing strokes, the protective effect of fluoride solutions is only slightly affected by brushing abrasion.