Tumor-Targeted Perfluorinated Micelles as Efficient Theranostic Agents Combining Positron Emission Tomography and Radiosensitization

We report the synthesis of biocompatible perfluorinated micelles designed to improve radiotherapeutic efficacy in a radioresistant tumor environment. In vitro and in vivo behaviors of perfluorinated micelles were assessed at both cellular and tissular levels. The micellar platform offers key advantages as theranostic tool: (i) small size, allowing deep tissue penetration; (ii) oxygen transport to hypoxic tissues; (iii) negligible toxicity in the absence of ionizing radiation; (iv) internalization into cancer cells; (v) potent radiosensitizing effect; and (vi) excellent tumor-targeting properties, as monitored by positron emission tomography. We have demonstrated strong in vitro radiosensitizing effects of the micelle and in vivo tumor targeting, making this nanometric carrier a promising tool for the potentiation of focused radiotherapy.

Fluorine-18 and Radiometal Labeling of Biomolecules via Disulfide Rebridging

Biomolecules labeled with positron-emitting radionuclides like fluorine-18 or radiometals like copper-64 and zirconium-89 are increasingly employed in nuclear medicine for diagnosis purposes. Given the fragility and complexity of these compounds, their labeling requires mild conditions. Besides, it is essential to develop methods inducing minimal modification of the tertiary structure, as it is fundamental for the biological activity of such complex entities. Given these requirements, disulfide rebridging represents a promising possibility since it allows protein modification as well as conservation of the tertiary structure. In this context, we have developed an original radiofluorinated dibromopyridazine dione prosthetic group for labeling of disulfide-containing biomolecules via rebridging. We employed it to radiolabel octreotide, a somatostatin analogue, and to radiolabel fragment antigen binding (Fab) targeting programmed death-ligand 1 (PD-L1), whose properties were then evaluated in vitro and in vivo by positron emission tomography (PET) imaging. We next extended our strategy to the radiolabeling of cetuximab, a monoclonal antibody, with various radiometals commonly used in PET imaging (zirconium-89, copper-64) by developing various rebridging molecules bearing the appropriate chelators. The stabilities of the radiolabeled antibody conjugates were assessed in biological conditions.

The multifaceted aspects of sleep and sleep-wake disorders following stroke

Sleep-wake disorders (SWD) are acknowledged risk factors for both ischemic stroke and poor cardiovascular and functional outcome after stroke. SWD are frequent following stroke, with sleep apnea (SA) being the most frequent SWD affecting more than half of stroke survivors. While sleep disturbances and SWD are frequently reported in the acute phase, they may persist in the chronic phase after an ischemic stroke. Despite the frequency and risk associated with SWD following stroke, screening for SWD remains rare in the clinical setting, due to challenges in the assessment of post-stroke SWD, uncertainty regarding the optimal timing for their diagnosis, and a lack of clear treatment guidelines (i.e., when to treat and the optimal treatment strategy). However, little evidence support the feasibility of SWD treatment even in the acute phase of stroke and its favorable effect on long-term cardiovascular and functional outcomes. Thus, sleep health recommendations and SWD treatment should be systematically embedded in secondary stroke prevention strategy. We therefore propose that the management of SWD associated with stroke should rely on a multidisciplinary approach, with an integrated diagnostic, treatment, and follow-up strategy. The challenges in the field are to improve post-stroke SWD diagnosis, prognosis and treatment, through a better appraisal of their pathophysiology and temporal evolution.

ImmunoPET imaging-based pharmacokinetic profiles of an antibody and its Fab targeting endothelin A receptors on glioblastoma stem cells in a preclinical orthotopic model

BACKGROUND

The resistance of glioblastoma stem cells (GSCs) to treatment is one of the causes of glioblastoma (GBM) recurrence. Endothelin A receptor (ETA) overexpression in GSCs constitutes an attractive biomarker for targeting this cell subpopulation, as illustrated by several clinical trials evaluating the therapeutic efficacy of endothelin receptor antagonists against GBM. In this context, we have designed an immunoPET radioligand combining the chimeric antibody targeting ETA, chimeric-Rendomab A63 (xiRA63), with 89Zr isotope and evaluated the abilities of xiRA63 and its Fab (ThioFab-xiRA63) to detect ETA+ tumors in a mouse model xenografted orthotopically with patient-derived Gli7 GSCs.

RESULTS

Radioligands were intravenously injected and imaged over time by µPET-CT imaging. Tissue biodistribution and pharmacokinetic parameters were analyzed, highlighting the ability of [89Zr]Zr-xiRA63 to pass across the brain tumor barrier and achieve better tumor uptake than [89Zr]Zr-ThioFab-xiRA63.

CONCLUSIONS

This study shows the high potential of [89Zr]Zr-xiRA63 in specifically targeting ETA+ tumors, thus raising the possibility of detecting and treating ETA+ GSCs, which could improve the management of GBM patients.

Sonoporation-assisted micelle delivery in subcutaneous glioma-bearing mice evaluated by PET/fluorescent bi-modal imaging

Tumor-specific drug delivery is a major challenge for the pharmaceutical industry. Nanocarrier systems have been widely investigated to increase and control drug delivery to the heterogeneous tumor microenvironment. Classically, the uptake of nanocarriers by solid tumor tissues is mainly mediated by the enhanced permeability and retention effect (EPR). This EPR effect depends on the tumor type, its location, the physicochemical properties of the carriers, and the blood perfusion of the tumoral lesions. The main goal of this study was to evaluate in vivo tumor uptake of micelle carriers, assisted by microbubble/ultrasound sonoporation. Micelles were tracked using bi-modal imaging techniques to precisely localize both the nanocarrier and its payload. Micelles were loaded with a near infrared fluorophore and radiolabeled with zirconium-89. Their pharmacokinetics, biodistribution and passive tumor targeting properties were evaluated in a subcutaneous glioblastoma (U-87 MG) mouse model using optical and PET imaging. Finally, accumulation and diffusion into the tumor micro-environment was investigated under microbubble-assisted sonoporation, which helped homogenize the delivery of the micelles. The in vivo experiments showed a good correlation between optical and PET images and demonstrated the stability of the micelles in biological media, their high and long-term retention in the tumors and their clearance through the hepato-biliary pathway. This study demonstrates that bi-modal imaging techniques are powerful tools for the development of new nanocarriers and that sonoporation is a promising method to homogenize nanomedicine delivery to tumors.

Design, Radiosynthesis, and Evaluation of New Fluorinated Analogs of MeDAS for Myelin PET Imaging

Positron emission tomography (PET) imaging of the myelin sheath is a powerful tool to investigate multiple sclerosis, monitor its evolution, and support drug development. Radiotracers based on N,N-dimethylaminostilbene (MeDAS) fluorinated analogs have been designed for myelin PET imaging but were never translated to humans. We have synthesized three original fluorinated analogs of MeDAS with low metabolic rates for which binding to myelin in a healthy rat brain was demonstrated by fluorescence microscopy. A tosyl precursor was synthesized for the lead compound PEGMeDAS and automated fluorine-18 radiolabeling afforded [¹⁸F]PEGMeDAS in 25 ± 5% radiochemical yield and 102 ± 15 GBq/μmol molar activity. Biodistribution in healthy rats demonstrated the brain penetration with low penetration of radiometabolites. However, E to Z isomerization observed in plasma hampers further investigations of this family of molecules and requires complementary data on the in vivo behavior of the Z isomer.

[CAR-T cells therapy in solid tumors : where are we now ?]

Chimeric antigen receptor T cells (also known as CAR-T cells) have already made their way into the therapeutic arsenal of specific hematological cancers, significantly improving the prognosis of patients. The prospect of such an innovative and effective treatment in solid tumors is very attractive. For this reason, several clinical studies have been initiated. Unfortunately, the antigenic heterogeneity and microenvironmental hostility of these solid tumors currently limit the effectiveness of CAR-T cells. New strategies are being sought to counteract these therapeutic obstacles.

Pharmacokinetics derived from PET imaging of inspiring radio-enhancer platinum nanoparticles

Personalized medicine approach in radiotherapy requires the delivery of precise dose to the tumor. The concept is to increase the effectiveness of radiotherapy while sparing the surrounding heathy tissue. This can be achieved by the use of high-Z metal-based nanoparticles (NPs) as radio-enhancers and PET imaging for mapping NPs distribution to guide the irradiation. In the present study, radio-enhancing platinum NPs were radiolabeled and imaged to assess their pharmacokinetics over time. PET imaging of these NPs revealed high enhanced permeation and retention effect. The maximal tumor accumulation (4.8 ± 0.8 %ID/cc) was observed at 24 h post-injection along with persistent accumulation of the NPs, especially at the tumor ring, even after several days. These properties positively suggest the potential clinical use of these NPs.

[Apalutamide, Erleada®]

Androgen-deprivation therapy (ADT), either bilateral orchiectomy or treatment with a gonadotropin-releasing hormone analogue agonist or antagonist, is the mainstay of treatment for advanced prostate cancer. In the metastatic setting, although ADT is initially effective, castration-resistant disease eventually develops in almost all men with prostate cancer. Since 2015, the addition of docetaxel, abiraterone, enzalutamide, apalutamide or darolutamide with docetaxel to ADT has been shown to improve overall survival (OS) of patients starting ADT for metastatic disease. Castration resistance occurs when disease progresses despite testosterone in the castrate range most commonly with or, more rarely, without detectable metastases. The addition of next-generation antiandrogens to ADT has been shown to improve OS in patients with high-risk nonmetastatic castration-resistant prostate cancer (nmCRPC) identified by a PSA doubling time (DT) ? 10 months. Apalutamide is a nonsteroidal antiandrogen agent that binds directly to the ligand-binding domain of the androgen receptor without agonist activity. When added to ADT apalutamide has been shown to improve OS by 35 % in patients starting ADT for metastatic prostate cancer both in patients with upfront metastatic disease or after previous treatment with curative intent. Similarly apalutamide has been shown to provide a 14-month OS improvement in patients with nmCRPC and short PSA DT. These OS benefits were obtained at no cost in terms of quality of life. Apalutamide is given orally once a day and is well tolerated. The most common side effects are fatigue, rash, hypertension and hot flushes. Potential interactions with concomitant medication should be taken into account.

Impact of drug consumption rooms on non-fatal overdoses, abscesses and emergency department visits in people who inject drugs in France: results from the COSINUS cohort

BACKGROUND

The effectiveness of drug consumption rooms (DCRs) for people who inject drugs (PWID) has been demonstrated for HIV and hepatitis C virus risk practices, and access to care for substance use disorders. However, data on other health-related complications are scarce. Using data from the French COSINUS cohort, we investigated the impact of DCR exposure on non-fatal overdoses, abscesses and emergency department (ED) visits, all in the previous 6 months.

METHODS

COSINUS is a 12-month prospective cohort study of 665 PWID in France studying DCR effectiveness on health. We collected data from face-to-face interviews at enrolment, and at 6 and 12 months of follow-up. After adjusting for other correlates (P-value < 0.05), the impact of DCR exposure on each outcome was assessed using a two-step Heckman mixed-effects probit model, allowing us to adjust for potential non-randomization bias due to differences between DCR-exposed and DCR-unexposed participants, while taking into account the correlation between repeated measures.

RESULTS

At enrolment, 21%, 6% and 38% of the 665 participants reported overdoses, abscesses and ED visits, respectively. Multivariable models found that DCR-exposed participants were less likely to report overdoses [adjusted coefficient (95% CI): -0.47 (-0.88; -0.07), P = 0.023], abscesses [-0.74 (-1.11; -0.37), P < 0.001] and ED visits [-0.74 (-1.27; -0.20), P = 0.007].

CONCLUSION

This is the first study to show the positive impact of DCR exposure on abscesses and ED visits, and confirms DCR effectiveness in reducing overdoses, when adjusting for potential non-randomization bias. Our findings strengthen the argument to expand DCR implementation to improve PWID injection environment and health.

[Management of metastatic hormone-naive prostate cancer at diagnosis]

In Belgium, 12 % of patients present with upfront metastatic hormone-naive prostate cancer. Surgical or medical castration has been the only approved treatment for decades. Since 2014, several randomized trials have demonstrated that survival could be significantly improved in patients who are deemed fit enough to cope with the potential added side-effects. Docetaxel chemotherapy and androgen receptor axis-targeted next generation hormonal agents such as abiraterone, enzalutamide and apalutamide have been shown to improve overall survival when given within 12 weeks after castration initiation. Similarly, prostate radiotherapy, in the absence of urological contraindications, might also improve overall survival in patients presenting with less than 5 bone metastases. How these strategies can be combined remains a matter of debate and is currently under investigation.

Do DSM-5 substance use disorder criteria differ by user care settings? An item response theory analysis approach

AIM

To examine differences in the psychometric characteristics of diagnostic criteria for Substance Use Disorders (SUD) between substance users in harm reduction settings (HR) and substance users seeking treatment (Tx).

METHODS

Differential Item and Test Functioning (DIF & DTF) analysis were performed to examine differences in the difficulty of endorsement and in discrimination of the 11 diagnostic criteria and to test if the criteria set as a whole (the "test") functioned differently by care settings (Tx vs. HR) for alcohol, cocaine, cannabis, opiates and tobacco. To test uniform and nonuniform DIF, multiple indicator multiple cause (MIMIC) structural equation models were used.

RESULTS

Regardless of the substance, the DSM-5 criteria "craving", "large amount", "time spent", "tolerance" and "activities given up" had similar functioning by care settings. Little evidence for DIF was found for other criteria. The criteria set as a whole did not function differently by care settings for alcohol, cocaine and tobacco. At the same trait severity, compared to HR, the Tx subgroup had a greater number of endorsed criteria for cannabis and a smaller number of endorsed criteria for opioids.

CONCLUSION

The unidimensionality of the 11 DSM-5 criteria and applicability of all criteria and diagnosis was confirmed in this large sample of problematic substance users. While the majority of the criteria related to loss of control of substance use, functioned well in both care settings, the criteria related to consequences of substance use had several differential functioning.

[Impact of prematurity on the optic nerve]

INTRODUCTION

Thanks to the progress made in the past few years in pediatric intensive care as well as the increased survival of preterm infants, the consequences of premature birth are increasingly well documented. With regard to ophthalmologic complications, retinopathy of prematurity is well described, but the optic nerve may also be affected. The goal of this study is to compare the optic nerves of preterm infants as a function of their gestational period with a control group of the same age.

MATERIALS AND METHODS

We conducted a case-control study pairing a full-term infant with each preterm infant. Inclusion criteria were: any child from 5- to 10-years-old, separated into three sub-groups according to their degree of prematurity. Variables were: cup/disc ratio, ocular biometry, intraocular pressure and RNFL thickness.

RESULTS

Thirty-seven preterm infants and 37 controls were included in the study. The mean age at the time of inclusion was 7.05 years for the preterm group and 7.19 years for the control group. No significant difference was observed in axial length or spherical equivalent (P=0.31 and P=0.98, respectively). No significant difference was observed in pachymetry or intraocular pressure (P=0.28 and P=0.22, respectively). We observed a significant increase of 0.1 in the cup/disc ratio of the preterm group compared to the control group (P<0.05). The preterm group cup/disc ratio was 0.36 versus 0.27 for the control group. No significant difference was observed in the 7 quadrants of RNFL between the two groups. However, when comparing infants born before 28 weeks gestation with the control group, we observed a mean decrease of 14.5 microns in the superior temporal sector (P=0.04), a 9 micron decrease in the global thickness G (P=0.03) and a 12.7 micron decrease in the nasal sector (P=0.01).

CONCLUSIONS

In the case of the studied children (aged 5 to 10), the reduced RNFL fiber thickness is a phenomenon dependent essentially on the stage of prematurity. It would be useful to follow these preterm populations over the long term and to compare them to a matched control group to be able to obtain functional results.

Determination of immunoglobulin concentrations and genetic parameters for colostrum and calf serum in Charolais animals

Colostrum samples from 366 Charolais primiparous cows, as well as serum from their calves at 24 to 48 h of age, were collected to gain an overview of the situation regarding passive immune transfer in beef cattle, from both the phenotypic and genetic points of view. All samples were analyzed to quantify their G₁ immunoglobulins by radial immunodiffusion (RID) and their IgG, IgA, and IgM using ELISA. The average concentrations obtained in colostrum were 84 mg/mL for RID-IgG₁, and 158 mg/mL, 4.5 mg/mL and 10.8 mg/mL for ELISA-IgG, -IgA, and -IgM, respectively. The corresponding values in calf serum were 19.9, 30.6, 1.0, and 1.9 mg/mL. Apart from the general environmental effect (farm-year combination and laboratory conditions), the characteristics of the dams tested did not reveal any influence on colostrum immunoglobulin concentrations. Calving difficulty, as well as the birth weight and sex of calves, were found to be associated with serum concentrations in some cases. Heritability estimates were low to moderate, with the highest being for RID-IgG₁ in colostrum (h² = 0.28, standard error = 0.14) and serum (h² = 0.36, standard error = 0.18). Phenotypic correlations among the different immunoglobulins were generally positive or null, and none of the genetic correlations were significant due to large standard errors. The phenotypic correlation between dam colostrum and calf serum values was 0.2 for RID-IgG₁ and null for the 3 ELISA measurements. The correlation between RID-IgG₁ and ELISA-IgG was, unexpectedly, null for colostrum and 0.4 for serum. Increased RID-IgG₁ levels in calf serum were associated with improved survival, as well as better early growth and fewer health problems. These results thus showed that despite generally higher concentrations in beef than in dairy cattle, passive transfer was unsuccessful in a considerable number of calves. This should be brought to the attention of breeders to avoid negative effects on survival and subsequent performance. The heritability estimates were encouraging; however, obtaining phenotypes on a large scale constitutes a real limitation regarding these traits.

Binding mode of Pyridoclax to myeloid cell leukemia-1 (Mcl-1) revealed by nuclear magnetic resonance spectroscopy, docking and molecular dynamics approaches

Myeloid cell leukemia-1 (Mcl-1) is an anti-apoptotic member of the Bcl-2 family proteins. Its amplification is one of the most frequent genetic aberrations found in human cancers. Pyridoclax, a promising BH3 mimetic inhibitor, interacts directly with Mcl-1 and induces massive apoptosis at a concentration of 15 µM in combination with anti-Bcl-x_L strategies in chemo-resistant ovarian cancer cell lines. In this study, a combined experimental and theoretical approach was used to investigate the binding mode of Pyridoclax to Mcl-1. The representative poses generated from dynamics simulations compared with NMR data revealed: (i) Pyridoclax bound to P1 and P2 pockets of Mcl-1 BH3 binding groove through its styryl and methyl groups establishing mainly hydrophobic contacts, (ii) one of the ending pyridines interacts through electrostatic interaction with K234 side chain, a negatively charged residue present only in this position in Mcl-1. Communicated by Ramaswamy H. Sarma.

Anti-NKG2A mAb Is a Checkpoint Inhibitor that Promotes Anti-tumor Immunity by Unleashing Both T and NK Cells

Checkpoint inhibitors have revolutionized cancer treatment. However, only a minority of patients respond to these immunotherapies. Here, we report that blocking the inhibitory NKG2A receptor enhances tumor immunity by promoting both natural killer (NK) and CD8⁺ T cell effector functions in mice and humans. Monalizumab, a humanized anti-NKG2A antibody, enhanced NK cell activity against various tumor cells and rescued CD8⁺ T cell function in combination with PD-x axis blockade. Monalizumab also stimulated NK cell activity against antibody-coated target cells. Interim results of a phase II trial of monalizumab plus cetuximab in previously treated squamous cell carcinoma of the head and neck showed a 31% objective response rate. Most common adverse events were fatigue (17%), pyrexia (13%), and headache (10%). NKG2A targeting with monalizumab is thus a novel checkpoint inhibitory mechanism promoting anti-tumor immunity by enhancing the activity of both T and NK cells, which may complement first-generation immunotherapies against cancer.

•

Blocking NKG2A unleashes both T and NK cell effector functions

•

Combined blocking of the NKG2A and the PD-1 axis promotes anti-tumor immunity

•

Blocking NKG2A and triggering CD16 illustrates the efficacy of dual checkpoint therapy

Abstract 2714: Combination of monalizumab and durvalumab as a potent immunotherapy treatment for solid human cancers

Inhibitory CD94-NKG2A (Natural Killer Group 2A) receptors are expressed on subsets of natural killer (NK) cells, γδ and CD8+ T cells. HLA-E (Human Leukocytes Antigen-E), the ligand for CD94-NKG2A, is upregulated on cancer cells of several solid tumors, providing a negative regulatory signal to tumor-infiltrating lymphocytes (TILs). Blockade of this immune checkpoint pathway with anti-NKG2A monoclonal antibodies (Ab) enhances NK cell responses to tumor cells in vitro and in humanized mice. Here, we describe NK and CD8+ T cell infiltrates in several human solid tumors by immunohistochemistry (IHC) and multicolor flow cytometry. We then studied the effects of in vitro targeting both pathways on primary human NK and CD8+ T cells. By using IHC on formalin-fixed paraffin-embedded samples on cohorts of solid tumors i.e. non-small cell lung cancer (NSCLC, n=45), stomach tumor (n=76), colorectal cancer (CRC, n=103), head and neck tumor (HNSCC, n=68), pancreatic tumors (n=77) and renal cell carcinoma (RCC, n=75), we observed NKp46+ NK cells in the large majority of cancer types (especially in RCC, HNSCC and stomach cancers). CD8+ T cells were found at significantly higher densities in all tumor types. In another cohort of HNSCC samples (n=60), higher proportions of CD94+ lymphocytes were found within the tumor islets both in the primary tumors and in the metastatic lymph nodes. In addition, in CRC patients with liver metastasis (n=101), high CD94+ cell densities were associated with poor overall survival. These data suggest that NKG2A blockade might unleash NK and T cells that are present in close contact to tumor cells. As previously shown, we confirmed that CD94-NKG2A ligand, HLA-E, was expressed by tumor cells in the large majority of solid tumor. In addition, high PD-L1 expressions were observed in NSCLC, stomach tumors, CRC and HNSCC. Flow cytometry analyses revealed that NK and CD8+ T cells co-expressing NKG2A and PD-1 were more numerous in tumor compared to matched peripheral blood and adjacent tissues of NSCLC and HNSCC patients. To mimic the “NKG2A+PD-1+” TILs phenotype, chronic stimulation of peripheral blood cells from healthy volunteers was performed using IL-15. The conditions led to the induction of NKG2A and PD-1 on NK and antigen-specific CD8+ T cell subsets. These effector cells were then co-cultured with tumor cell lines expressing HLA-E +/- PD-L1. We showed that monalizumab, a first-in class anti-NKG2A Ab, combined with durvalumab resulted in higher responses (CD107 mobilization and IFN-γ production) compared to each Ab alone. These data were confirmed in a syngeneic mouse model where both NK and CD8+ T cells were found to be involved in tumor rejection. Together, these data confirm that blocking NKG2A can potentiate the anti-tumor efficacy of PD-1 inhibitors and support the rationale for ongoing clinical trials investigating the monalizumab/durvalumab combination (NCT02671435 and NCT03088059).

Citation Format: Caroline Soulas, Romain Remark, Vedran Brezar, Julie Lopez, Elodie Bonnet, Flavien Caraguel, Ana Lalanne, Caroline Hoffmann, Caroline Denis, Thomas Arnoux, Clarisse Caillet, Arnaud Dujardin, Guillaume Habif, Olivier Lantz, Cécile Bonnafous, Eric Vivier, Pascale Andre. Combination of monalizumab and durvalumab as a potent immunotherapy treatment for solid human cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2714.

[Update on developemental dyspraxia in children]

After having explained what is dyspraxia, we will briefly talk about narcissistic issues related to school term. Indeed, the defensive tools used by children to deal with learning disabilities are varied and not much specific, which will complicate the medical approach. Then we will describe the symptoms that are specific to search in the history and the first clinic appointment in cases of suspected dyspraxia. Finally, we will give details of how we must consider the exploration and the multidisciplinary taking over of the disorder.

Thermal tolerance in the keystone species Daphnia magna-a candidate gene and an outlier analysis approach

Changes in temperature have occurred throughout Earth's history. However, current warming trends exacerbated by human activities impose severe and rapid loss of biodiversity. Although understanding the mechanisms orchestrating organismal response to climate change is important, remarkably few studies document their role in nature. This is because only few systems enable the combined analysis of genetic and plastic responses to environmental change over long time spans. Here, we characterize genetic and plastic responses to temperature increase in the aquatic keystone grazer Daphnia magna combining a candidate gene and an outlier analysis approach. We capitalize on the short generation time of our species, facilitating experimental evolution, and the production of dormant eggs enabling the analysis of long-term response to environmental change through a resurrection ecology approach. We quantify plasticity in the expression of 35 candidate genes in D. magna populations resurrected from a lake that experienced changes in average temperature over the past century and from experimental populations differing in thermal tolerance isolated from a selection experiment. By measuring expression in multiple genotypes from each of these populations in control and heat treatments, we assess plastic responses to extreme temperature events. By measuring evolutionary changes in gene expression between warm- and cold-adapted populations, we assess evolutionary response to temperature changes. Evolutionary response to temperature increase is also assessed via an outlier analysis using EST-linked microsatellite loci. This study provides the first insights into the role of plasticity and genetic adaptation in orchestrating adaptive responses to environmental change in D. magna.

Abstract 3222: Preclinical development of a humanized blocking antibody targeting the CD39 immune checkpoint for cancer immunotherapy

CD39 (ENTPD1) is a cell membrane ectonucleotidase that hydrolyzes extracellular immunoactivating ATP and ADP into AMP, which can be further hydrolyzed by ectonucleotidase CD73 into immunosuppressive adenosine. Within the tumor microenvironment, adenosine accumulation causes immune suppression and dysregulation of immune cell infiltrates resulting in tumor spreading. The role of CD39 expression on both Tregs and on tumor cells in promoting immunosuppression has been demonstrated in several reports. Blockade of CD39 may promote anti-tumor immunity by directly accumulating immunostimulating ATP and indirectly by reducing adenosine accumulation. Here, we describe the discovery and preclinical development of an anti-huCD39 blocking antibody for cancer immunotherapy. Parental anti-huCD39 mouse monoclonal antibody was humanized. The humanized mAb specifically binds huCD39 protein, but not CD39-like proteins. Nanomolar affinities for human CD39 were measured in SPR studies on recombinant CD39 protein and in flow cytometry titration studies on CD39 expressing transfectants and tumor cell lines. The humanized mAb blocked human CD39 ATPase activity in vitro in the nanomolar range, as demonstrated using transfected cells, CD39-expressing tumor cell lines, as well as human PBMC and ex-vivo isolated fresh tumor samples. The humanized mAb cross-reacted on cynomolgus CD39 and blocked ATPase activity on cynomolgus PBMC with similar efficacy as on human PBMC. Finally, treatment with blocking anti-CD39 mAb inhibited tumor growth in vivo in mouse tumor models. Taken together, these data support the clinical development of anti-CD39 neutralizing mAb for cancer immunotherapy.

Citation Format: Severine Augier, Ivan Perrot, Cecile Dejou, Rachel Joly, Stephane Delahaye, Helene Rispaud Blanc, Caroline Denis, Laurent Gauthier, Armand Bensussan, Jean-francois Eliaou, Yannis Morel, Nathalie Bonnefoy, Jeremy Bastid, Carine Paturel. Preclinical development of a humanized blocking antibody targeting the CD39 immune checkpoint for cancer immunotherapy. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3222.

[Review of reimbursement for instrumental techniques used for assisted coughing and thoracic expansion. A French National Health Authority assessment (HAS)]

INTRODUCTION

In France, children with neuromuscular diseases and patients with traumatic spinal cord injuries receive reimbursement for home use of intermittent positive-pressure breathing and mechanical in-exsufflators devices. The aim of the study was to update the indications for reimbursement for these both devices.

METHODS

A literature review was conducted with several bibliographic databases using the main keywords: intermittent positive-pressure breathing, mechanical insufflation, mechanically-assisted cough, airway clearance. Nine health professionals were interviewed during two meetings. One health professional was interviewed via a questionnaire. An estimation of the population treated with in-exsufflators or intermittent positive-pressure breathing was undertaken from consumer data available for all beneficiaries of the health insurance system.

STATE OF THE ART

The review identified 111 references which included 14 clinical practice guidelines, two systematic reviews and one randomized controlled trial. Some clinical data were available. Clinical practice guidelines were in favor of using intermittent positive-pressure breathing and in-exsufflators in patients with neuromuscular disease and spinal cord injuries. The healthcare professionals emphasized the need to reimburse the patient for home use of intermittent positive-pressure breathing and in-exsufflators. The patient population treated in the identified clinical situations was estimated at 3100 per year.

CONCLUSIONS

Despite the low level of evidence and after interviewing healthcare professionals, the Haute Autorité de santé (HAS) recommended reimbursement of the costs of in-exsufflators (assisted coughing) and intermittent positive-pressure breathing (thoracic expansion) devices in adults and children with neurological and neuromuscular disease, including spinal cord injury.

Validation of a predictive model coupling gas transfer and microbial growth in fresh food packed under modified atmosphere

Predicting microbial safety of fresh products in modified atmosphere packaging implies to take into account the dynamic of O2, CO2 and N2 exchanges in the system and its effect on microbial growth. In this paper a mechanistic model coupling gas transfer and predictive microbiology was validated using dedicated challenge-tests performed on poultry meat, fresh salmon and processed cheese, inoculated with either Listeria monocytogenes or Pseudomonas fluorescens and packed in commercially used packaging materials (tray + lid films). The model succeeded in predicting the relative variation of O2, CO2 and N2 partial pressure in headspace and the growth of the studied microorganisms without any parameter identification. This work highlighted that the respiration of the targeted microorganism itself and/or that of the naturally present microflora could not be neglected in most of the cases, and could, in the particular case of aerobic microbes contribute to limit the growth by removing all residual O2 in the package. This work also confirmed the low sensitivity of L. monocytogenes toward CO2 while that of P. fluorescens permitted to efficiently prevent its growth by choosing the right combination of packaging gas permeability value and initial % of CO2 initially flushed in the pack.

[Controversies around the diagnosis of ADHD]

Complaints about restlessness, difficulties to focus and impulsivity are amongst the most frequent reasons for child psychiatric consultations. Those complaints refer to the core symptoms of the ADHD. However, the diagnosis of ADHD is delicate to establish and subject to several controversies regarding its etiopathological origins and, therefore, its treatment. In practice, those situations include very different cases and it seems obvious that this is a polyfactorial disorder, no single factor alone being sufficient to account for all the difficulties experienced by the children. It would therefore be simplistic to consider the ADHD as issued only from a neurobiological disorder and to consider a drug treatment, only. We are rather in favor of an integrative approach and a global treatment on a case by case basis.

Evaluation of New Fluorescent Lipophosphoramidates for Gene Transfer and Biodistribution Studies after Systemic Administration

The objective of lung gene therapy is to reach the respiratory epithelial cells in order to deliver a functional nucleic acid sequence. To improve the synthetic carrier's efficacy, knowledge of their biodistribution and elimination pathways, as well as cellular barriers faced, depending on the administration route, is necessary. Indeed, the in vivo fate guides the adaptation of their chemical structure and formulation to increase their transfection capacity while maintaining their tolerance. With this goal, lipidic fluorescent probes were synthesized and formulated with cationic lipophosphoramidate KLN47 (KLN: Karine Le Ny). We found that such formulations present constant compaction properties and similar transfection results without inducing additional cytotoxicity. Next, biodistribution profiles of pegylated and unpegylated lipoplexes were compared after systemic injection in mice. Pegylation of complexes led to a prolonged circulation in the bloodstream, whereas their in vivo bioluminescent expression profiles were similar. Moreover, systemic administration of pegylated lipoplexes resulted in a transient liver toxicity. These results indicate that these new fluorescent compounds could be added into lipoplexes in small amounts without perturbing the transfection capacities of the formulations. Such additional properties allow exploration of the in vivo biodistribution profiles of synthetic carriers as well as the expression intensity of the reporter gene.

Cationic lipophosphoramidates with two different lipid chains: synthesis and evaluation as gene carriers

The synthesis of a series of new cationic lipids possessing two different lipid chains is detailed. The transfection efficacies have shown the interest to associate a phytanyl chain with either, a lauryl or oleyl chain.

[Mutism]

Mutism is a symptom we see in consultation for an absence or lack of langage acquisition and/or for relationship problems (isolation, withdrawal, crisis when breaking up) alerting the family. The differential diagnosis is complex and mutism can be symptomatic of several personality psychopathological structures. After a literature review, we shall describe three clinical cases and discuss the difficult approach to this symptom, its psychopathological features, as well as its pronostic and therapeutic aspects".

[(2R,3R)-3-(4-Nitrophenyl)aziridin-2-yl]methanol monohydrate

The title monohydrate, C₉H₁₀N₂O₃·H₂O, contains an aziridine ring including two contiguous stereocenters, both of which exhibit an R configuration. The methyl­hydroxy and nitro­phenyl groups are cis-disposed about the aziridine ring. The mean plane of the benzene ring is tilted to the aziridine ring by 66.65 (8)°. The nitro group is nearly coplanar with the benzene ring [dihedral angle = 2.5 (2)°]. In the crystal, the components are linked by N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds, generating supra­molecular layers parallel to (001).

(4S)-4-[(R)-Chloro-(4-nitro-phen-yl)meth-yl]-1,3-oxazolidin-2-one

In the title compound, C₁₀H₉ClN₂O₄, the oxazolidinone ring adopts a near-planar conformation, with mean and maximum deviations of 0.0204 (8) and 0.0328 (8) Å, respectively. The nitro group is twisted slightly from the plane of the benzene ring, making a dihedral angle of 6.79 (3)°. The dihedral angle between the mean oxazolidinone plane and the benzene ring is 56.21 (3)°. In the crystal, N—H⋯O hydrogen bonds and N—O⋯π inter­actions [O⋯centroid distances = 3.478 (1) and 3.238 (1) Å] dominate the packing, forming infinite zigzag chains along the b-axis direction. Neighbouring chains are linked together through C—H⋯O and C—H⋯Cl inter­actions. The absolute configuration of the two stereogenic centres was determined using the anomalous dispersion of the Cl atom.

[Cervical ripening with balloon catheter for scared uterus: a three-year retrospective study]

OBJECTIVES

To evaluate, for women with scared uterus, the mechanical cervical ripening with balloon catheter.

METHODS

We conducted a retrospective study of our practice of ripening for scared uterus from january 2010 to august 2012. Feasibility, Bishop's score, birth modalities and complications for mothers and babies during this ripening were studied.

RESULTS

Thirty-nine medical files were analysed. All patients could have mechanical ripening independently of the internal os status (open or not). The cervical ripening with balloon catheter improved Bishop's score before induction of labour, from 3.54 ± 1.23 to 5.38 ± 1.47 (p=0.02). 64.1% of women had a vaginal delivery. Concerning the predictive factors for vaginal delivery, we only found significant influence of a body mass index less than 30kg/m² (p=0.03). We didn't find any maternal or neonatal complications in our population.

CONCLUSION

Mechanical ripening for scared uterus seems to be a useful option to improve vaginal delivery without increasing maternal and foetal morbidity. Anyway, these results have to be confirmed by a randomized controlled trial on a specific scared uterus population.

Endurance but not resistance training increases intra-myocellular lipid content and β-hydroxyacyl coenzyme A dehydrogenase activity in active elderly men

AIM

Endurance and resistance training (ET and RT, respectively) in older subjects have been proven beneficial against metabolic or cardiovascular disorders and against sarcopaenia respectively. Like ET, RT may also increase muscle oxidative capacities. In addition, it could be questioned whether RT, similarly to ET, is able to increase muscle energetic stores such as intra-myocellular lipids (IMCL) and glycogen contents. To evaluate a possible ET- and RT-induced parallel increase in oxidative capacity and energetic stores, active elderly men (72 ± 2 years) were submitted to a 14-week training programme (three times week(-1) ) combining lower body endurance and upper body resistance.

METHODS

Muscle samples were collected in ET vastus lateralis (VLat) and RT deltoid (Del) muscles before and after training. IMCL and glycogen contents were assessed by histochemistry (Oil Red O and periodic acid-Schiff staining, respectively) and by biochemical assay for glycogen. Citrate synthase (CS, marker of mitochondrial citric acid cycle), β-hydroxyacyl coenzyme A dehydrogenase (β-HAD, beta-oxidation) and phosphofructokinase (PFK, glycolytic pathway) activities were determined and so was the capillary interface index (LC/PF).

RESULTS

Both training regimens significantly increased CS and LC/PF in ET-VLat and RT-Del. IMCL content and β-HAD activity increased (P < 0.05) only in ET-VLat, whereas PFK activity increased (P < 0.05) only in RT-Del. Glycogen content was not significantly altered in response to training in both muscles.

CONCLUSION

Unlike RT, which induced an increase in PFK, ET is able to increase IMCL content and β-oxidation capacity in active elderly men, even though both training may improve CS activity and LC/PF.