Recent Submissions

  • Surfactant replacement therapy in combination with different non-invasive ventilation techniques in spontaneously-breathing, surfactant-depleted adult rabbits.

    Ricci, Francesca; Casiraghi, Costanza; Storti, Matteo; D'Alò, Francesco; Catozzi, Chiara; Ciccimarra, Roberta; Ravanetti, Francesca; Cacchioli, Antonio; Villetti, Gino; Civelli, Maurizio; Murgia, Xabi; Carnielli, Virgilio; Salomone, Fabrizio; HIPS, Helmholtz-Institut füt Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (2018-01-01)
    Nasal intermittent positive pressure ventilation (NIPPV) holds great potential as a primary ventilation support method for Respiratory Distress Syndrome (RDS). The use of NIPPV may also be of great value combined with minimally invasive surfactant delivery. Our aim was to implement an in vivo model of RDS, which can be managed with different non-invasive ventilation (NIV) strategies, including non-synchronized NIPPV, synchronized NIPPV (SNIPPV), and nasal continuous positive airway pressure (NCPAP). Forty-two surfactant-depleted adult rabbits were allocated in six different groups: three groups of animals were treated with only NIV for three hours (NIPPV, SNIPPV, and NCPAP groups), while three other groups were treated with surfactant (SF) followed by NIV (NIPPV+SF, SNIPPV+SF, and NCPAP+SF groups). Arterial gas exchange, ventilation indices, and dynamic compliance were assessed. Post-mortem the lungs were sampled for histological evaluation. Surfactant depletion was successfully achieved by repeated broncho-alveolar lavages (BALs). After BALs, all animals developed a moderate respiratory distress, which could not be reverted by merely applying NIV. Conversely, surfactant administration followed by NIV induced a rapid improvement of arterial oxygenation in all surfactant-treated groups. Breath synchronization was associated with a significantly better response in terms of gas exchange and dynamic compliance compared to non-synchronized NIPPV, showing also the lowest injury scores after histological assessment. The proposed in vivo model of surfactant deficiency was successfully managed with NCPAP, NIPPV, or SNIPPV; this model resembles a moderate respiratory distress and it is suitable for the preclinical testing of less invasive surfactant administration techniques.
  • Medium throughput breathing human primary cell alveolus-on-chip model.

    Stucki, Janick D; Hobi, Nina; Galimov, Artur; Stucki, Andreas O; Schneider-Daum, Nicole; Lehr, Claus-Michael; Huwer, Hanno; Frick, Manfred; Funke-Chambour, Manuela; Geiser, Thomas; Guenat, Olivier T; HIPS, Helmholtz-Institut füt Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (2018-09-25)
    Organs-on-chips have the potential to improve drug development efficiency and decrease the need for animal testing. For the successful integration of these devices in research and industry, they must reproduce in vivo contexts as closely as possible and be easy to use. Here, we describe a 'breathing' lung-on-chip array equipped with a passive medium exchange mechanism that provide an in vivo-like environment to primary human lung alveolar cells (hAEpCs) and primary lung endothelial cells. This configuration allows the preservation of the phenotype and the function of hAEpCs for several days, the conservation of the epithelial barrier functionality, while enabling simple sampling of the supernatant from the basal chamber. In addition, the chip design increases experimental throughput and enables trans-epithelial electrical resistance measurements using standard equipment. Biological validation revealed that human primary alveolar type I (ATI) and type II-like (ATII) epithelial cells could be successfully cultured on the chip over multiple days. Moreover, the effect of the physiological cyclic strain showed that the epithelial barrier permeability was significantly affected. Long-term co-culture of primary human lung epithelial and endothelial cells demonstrated the potential of the lung-on-chip array for reproducible cell culture under physiological conditions. Thus, this breathing lung-on-chip array, in combination with patients' primary ATI, ATII, and lung endothelial cells, has the potential to become a valuable tool for lung research, drug discovery and precision medicine.
  • Vitamin D Deficiency Does Not Result in a Breach of Host Defense in Murine Models of Pneumonia.

    Niederstrasser, Julia; Herr, Christian; Wolf, Lisa; Lehr, Claus M; Beisswenger, Christoph; Bals, Robert; HIPS, Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus 8.1, 66123 Saarbrücken, Germany. (2016-11-01)
    Vitamin D (VitD) has a role in the regulation of calcium and phosphate metabolism and in addition impacts the activity of the immune system. VitD deficiency might be linked to increased susceptibility to respiratory tract infection. The aim of the present study was to characterize the impact of VitD deficiency on the susceptibility to bacterial infection in murine models. C57BL/6N mice were fed a diet with or without VitD for 10 weeks. The VitD-deficient or -sufficient mice were infected with Pseudomonas aeruginosa or Streptococcus pneumoniae The colonization and inflammatory response in the lung were analyzed at defined time points. The serum 25-hydroxy-VitD concentration was significantly lower in mice on the VitD-deficient diet. In infection experiments with Pseudomonas aeruginosa or Streptococcus pneumoniae, no differences could be observed in the numbers of viable bacteria or in differential cell counts in the bronchoalveolar lavage fluids. Measurements of inflammatory cytokines (KC and interleukin-1β [IL-1β]) did not show significant differences between the groups. In conclusion, VitD-deficient animals did not show significantly increased susceptibility to infection or an altered course of infection. The immune systems of humans and mice likely respond differently to VitD. Murine models are likely not appropriate for drawing conclusions on the role of VitD in human pulmonary host defense.
  • Kinetics of mRNA delivery and protein translation in dendritic cells using lipid-coated PLGA nanoparticles.

    Yasar, Hanzey; Biehl, Alexander; De Rossi, Chiara; Koch, Marcus; Murgia, Xabi; Loretz, Brigitta; Lehr, Claus-Michael; HIPS, Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus 8.1, 66123 Saarbrücken, Germany. (2018-09-19)
    Messenger RNA (mRNA) has gained remarkable attention as an alternative to DNA-based therapies in biomedical research. A variety of biodegradable nanoparticles (NPs) has been developed including lipid-based and polymer-based systems for mRNA delivery. However, both systems still lack in achieving an efficient transfection rate and a detailed understanding of the mRNA transgene expression kinetics. Therefore, quantitative analysis of the time-dependent translation behavior would provide a better understanding of mRNA's transient nature and further aid the enhancement of appropriate carriers with the perspective to generate future precision nanomedicines with quick response to treat various diseases. A lipid-polymer hybrid system complexed with mRNA was evaluated regarding its efficiency to transfect dendritic cells (DCs) by simultaneous live cell video imaging of both particle uptake and reporter gene expression. We prepared and optimized NPs consisting of poly (lactid-co-glycolid) (PLGA) coated with the cationic lipid 1, 2-di-O-octadecenyl-3-trimethylammonium propane abbreviated as LPNs. An earlier developed polymer-based delivery system (chitosan-PLGA NPs) served for comparison. Both NPs types were complexed with mRNA-mCherry at various ratios. While cellular uptake and toxicity of either NPs was comparable, LPNs showed a significantly higher transfection efficiency of ~ 80% while chitosan-PLGA NPs revealed only ~ 5%. Further kinetic analysis elicited a start of protein translation after 1 h, with a maximum after 4 h and drop of transgene expression after 48 h post-transfection, in agreement with the transient nature of mRNA. Charge-mediated complexation of mRNA to NPs enables efficient and fast cellular delivery and subsequent protein translation. While cellular uptake of both NP types was comparable, mRNA transgene expression was superior to polymer-based NPs when delivered by lipid-polymer NPs.
  • Extracellular vesicles protect glucuronidase model enzymes during freeze-drying.

    Frank, Julia; Richter, Maximilian; de Rossi, Chiara; Lehr, Claus-Michael; Fuhrmann, Kathrin; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus 8.1, 66123 Saarbrücken, Germany. (2018-08-17)
    Extracellular vesicles (EVs) are natural nanoparticles that play important roles in intercellular communication and are increasingly studied for biosignalling, pathogenesis and therapy. Nevertheless, little is known about optimal conditions for their transfer and storage, and the potential impact on preserving EV-loaded cargoes. We present the first comprehensive stability assessment of different widely available types of EVs during various storage conditions including -80 °C, 4 °C, room temperature, and freeze-drying (lyophilisation). Lyophilisation of EVs would allow easy handling at room temperature and thus significantly enhance their expanded investigation. A model enzyme, β-glucuronidase, was loaded into different types of EVs derived from mesenchymal stem cells, endothelial cells and cancer cells. Using asymmetric flow field-flow fractionation we proved that the model enzyme is indeed stably encapsulated into EVs. When assessing enzyme activity as indicator for EV stability, and in comparison to liposomes, we show that EVs are intrinsically stable during lyophilisation, an effect further enhanced by cryoprotectants. Our findings provide new insight for exploring lyophilisation as a novel storage modality and we create an important basis for standardised and advanced EV applications in biomedical research.
  • High-throughput phenotyping by applying digital morphometrics and fluorescence induction curves in seeds to identifying variations: A case study of Annona (Annonaceae) species

    Pontes, Montcharles S.; Montefusco-Pereira, Carlos V.; Misra, Biswapriya B.; Ribeiro-Junior, Howard L.; Graciano, Daniela E.; Santos, Jaqueline S.; Nobrega, Michele A.S.; Fernandes, Shaline S.L.; Caires, Anderson R.L.; Santiago, Etenaldo F.; HIPS, Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus 8.1, 66123 Saarbrücken, Germany.
  • A Model for the Transient Subdiffusive Behavior of Particles in Mucus.

    Ernst, Matthias; John, Thomas; Guenther, Marco; Wagner, Christian; Schaefer, Ulrich F; Lehr, Claus-Michael; HIPS, Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus 8.1, 66123 Saarbrücken, Germany. (2017-01-10)
    In this study we have applied a model to explain the reported subdiffusion of particles in mucus, based on the measured mean squared displacements (MSD). The model considers Brownian diffusion of particles in a confined geometry, made from permeable membranes. The applied model predicts a normal diffusive behavior at very short and long time lags, as observed in several experiments. In between these timescales, we find that the "subdiffusive" regime is only a transient effect, MSD∝τ
  • Combining MucilAir™ and Vitrocell Powder Chamber for the In Vitro Evaluation of Nasal Ointments in the Context of Aerosolized Pollen.

    Metz, Julia; Knoth, Katharina; Groß, Henrik; Lehr, Claus-Michael; Stäbler, Carolin; Bock, Udo; Hittinger, Marius; HIPS, Helmholtz-Institute für pharmazeutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2018-05-10)
    Hay fever is notoriously triggered when nasal mucosa is exposed to allergenic pollen. One possibility to overcome this pollen exposure may be the application of an ointment with physical protective effects. In this context, we have investigated Bepanthen Eye and Nose Ointment and the ointment basis petrolatum as reference while using contemporary in vitro techniques. Pollen from false ragweed () was used as an allergy-causing model deposited as aerosol using the Vitrocell Powder Chamber (VPC) on Transwell inserts, while being coated with either Bepanthen Eye and Nose Ointment and petrolatum. No pollen penetration into ointments was observed upon confocal scanning laser microscopy during an incubation period of 2 h at 37 °C. The cellular response was further investigated by integrating the MucilAir™ cell system in the VPC and by applying pollen to Bepanthen Eye and Nose Ointment covered cell cultures. For comparison, MucilAir™ were stimulated by lipopolysaccharides (LPS). No increased cytokine release of IL-6, TNF-α, or IL-8 was found after 4 h of pollen exposure, which demonstrates the safety of such ointments. Since nasal ointments act as a physical barrier against pollen, such preparations might support the prevention and management of hay fever.
  • Engineering Extracellular Vesicles with the Tools of Enzyme Prodrug Therapy.

    Fuhrmann, Gregor; Chandrawati, Rona; Parmar, Paresh A; Keane, Timothy J; Maynard, Stephanie A; Bertazzo, Sergio; Stevens, Molly M; HIPS, Helmholtz-Institute für pharmazeutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2018-02-23)
    Extracellular vesicles (EVs) have recently gained significant attention as important mediators of intercellular communication, potential drug carriers, and disease biomarkers. These natural cell-derived nanoparticles are postulated to be biocompatible, stable under physiological conditions, and to show reduced immunogenicity as compared to other synthetic nanoparticles. Although initial clinical trials are ongoing, the use of EVs for therapeutic applications may be limited due to undesired off-target activity and potential "dilution effects" upon systemic administration which may affect their ability to reach their target tissues. To fully exploit their therapeutic potential, EVs are embedded into implantable biomaterials designed to achieve local delivery of therapeutics taking advantage of enzyme prodrug therapy (EPT). In this first application of EVs for an EPT approach, EVs are used as smart carriers for stabilizing enzymes in a hydrogel for local controlled conversion of benign prodrugs to active antiinflammatory compounds. It is shown that the natural EVs' antiinflammatory potential is comparable or superior to synthetic carriers, in particular upon repeated long-term incubations and in different macrophage models of inflammation. Moreover, density-dependent color scanning electron microscopy imaging of EVs in a hydrogel is presented herein, an impactful tool for further understanding EVs in biological settings.
  • Starch-Chitosan Polyplexes: A Versatile Carrier System for Anti-Infectives and Gene Delivery

    Yasar, Hanzey; Ho, Duy-Khiet; De Rossi, Chiara; Herrmann, Jennifer; Gordon, Sarah; Loretz, Brigitta; Lehr, Claus-Michael; HIPS, Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus 8.1, 66123 Saarbrücken, Germany. (2018-03-01)
  • A miRNA181a/NFAT5 axis links impaired T cell tolerance induction with autoimmune type 1 diabetes.

    Serr, Isabelle; Scherm, Martin G; Zahm, Adam M; Schug, Jonathan; Flynn, Victoria K; Hippich, Markus; Kälin, Stefanie; Becker, Maike; Achenbach, Peter; Nikolaev, Alexei; Gerlach, Katharina; Liebsch, Nicole; Loretz, Brigitta; Lehr, Claus Michael; Kirchner, Benedikt; Spornraft, Melanie; Haase, Bettina; Segars, James; Küper, Christoph; Palmisano, Ralf; Waisman, Ari; Willis, Richard A; Kim, Wan-Uk; Weigmann, Benno; Kaestner, Klaus H; Ziegler, Anette-Gabriele; Daniel, Carolin; HIPS, Helmholtz-Institute für pharmazeutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2018-01-03)
    Molecular checkpoints that trigger the onset of islet autoimmunity or progression to human type 1 diabetes (T1D) are incompletely understood. Using T cells from children at an early stage of islet autoimmunity without clinical T1D, we find that a microRNA181a (miRNA181a)-mediated increase in signal strength of stimulation and costimulation links nuclear factor of activated T cells 5 (NFAT5) with impaired tolerance induction and autoimmune activation. We show that enhancing miRNA181a activity increases NFAT5 expression while inhibiting FOXP3+regulatory T cell (Treg) induction in vitro. Accordingly, Treginduction is improved using T cells from NFAT5 knockout (NFAT5ko) animals, whereas altering miRNA181a activity does not affect Treginduction in NFAT5ko T cells. Moreover, high costimulatory signals result in phosphoinositide 3-kinase (PI3K)-mediated NFAT5, which interferes with FoxP3+Treginduction. Blocking miRNA181a or NFAT5 increases Treginduction in murine and humanized models and reduces murine islet autoimmunity in vivo. These findings suggest targeting miRNA181a and/or NFAT5 signaling for the development of innovative personalized medicines to limit islet autoimmunity.
  • Calcifediol-loaded liposomes for local treatment of pulmonary bacterial infections.

    Castoldi, Arianna; Herr, Christian; Niederstraßer, Julia; Labouta, Hagar Ibrahim; Melero, Ana; Gordon, Sarah; Schneider-Daum, Nicole; Bals, Robert; Lehr, Claus Michael; HIPS, Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus 8.1, 66123 Saarbrücken, Germany. (2017-09)
    The influence of vitamin D3 and its metabolites calcifediol (25(OH)D) and calcitriol on immune regulation and inflammation is well described, and raises the question of potential benefit against bacterial infections. In the current study, 25(OH)D was encapsulated in liposomes to enable aerosolisation, and tested for the ability to prevent pulmonary infection by Pseudomonas aeruginosa. Prepared 25(OH)D-loaded liposomes were nanosized and monodisperse, with a negative surface charge and a 25(OH)D entrapment efficiency of approximately 23%. Jet nebulisation of liposomes was seen to yield an aerosol suitable for tracheo-bronchial deposition. Interestingly, 25(OH)D in either liposomes or ethanolic solution had no effect on the release of the proinflammatory cytokine KC from Pseudomonas-infected murine epithelial cells (LA-4); treatment of infected, human bronchial 16-HBE cells with 25(OH)D liposomes however resulted in a significant reduction in bacterial survival. Together with the importance of selecting an application-appropriate in vitro model, the current study illustrates the feasibility and practicality of employing liposomes as a means to achieve 25(OH)D lung deposition. 25(OH)D-loaded liposomes further demonstrated promising effects regarding prevention of Pseudomonas infection in human bronchial epithelial cells.
  • The bacterial cell envelope as delimiter of anti-infective bioavailability - An in vitro permeation model of the Gram-negative bacterial inner membrane.

    Graef, Florian; Vukosavljevic, Branko; Michel, Jean-Philippe; Wirth, Marius; Ries, Oliver; De Rossi, Chiara; Windbergs, Maike; Rosilio, Véronique; Ducho, Christian; Gordon, Sarah; Lehr, Claus Michael; HIPS, Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2016)
    Gram-negative bacteria possess a unique and complex cell envelope, composed of an inner and outer membrane separated by an intermediate cell wall-containing periplasm. This tripartite structure acts intrinsically as a significant biological barrier, often limiting the permeation of anti-infectives, and so preventing such drugs from reaching their target. Furthermore, identification of the specific permeation-limiting envelope component proves difficult in the case of many anti-infectives, due to the challenges associated with isolation of individual cell envelope structures in bacterial culture. The development of an in vitro permeation model of the Gram-negative inner membrane, prepared by repeated coating of physiologically-relevant phospholipids on Transwell®filter inserts, is therefore reported, as a first step in the development of an overall cell envelope model. Characterization and permeability investigations of model compounds as well as anti-infectives confirmed the suitability of the model for quantitative and kinetically-resolved permeability assessment, and additionally confirmed the importance of employing bacteria-specific base materials for more accurate mimicking of the inner membrane lipid composition - both advantages compared to the majority of existing in vitro approaches. Additional incorporation of further elements of the Gram-negative bacterial cell envelope could ultimately facilitate model application as a screening tool in anti-infective drug discovery or formulation development.
  • miRNA92a targets KLF2 and the phosphatase PTEN signaling to promote human T follicular helper precursors in T1D islet autoimmunity.

    Serr, Isabelle; Fürst, Rainer W; Ott, Verena B; Scherm, Martin G; Nikolaev, Alexei; Gökmen, Füsun; Kälin, Stefanie; Zillmer, Stephanie; Bunk, Melanie; Weigmann, Benno; Kunschke, Nicole; Loretz, Brigitta; Lehr, Claus Michael; Kirchner, Benedikt; Haase, Bettina; Pfaffl, Michael; Waisman, Ari; Willis, Richard A; Ziegler, Anette-G; Daniel, Carolin; Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2016)
    Aberrant immune activation mediated by T effector cell populations is pivotal in the onset of autoimmunity in type 1 diabetes (T1D). T follicular helper (TFH) cells are essential in the induction of high-affinity antibodies, and their precursor memory compartment circulates in the blood. The role of TFH precursors in the onset of islet autoimmunity and signaling pathways regulating their differentiation is incompletely understood. Here, we provide direct evidence that during onset of islet autoimmunity, the insulin-specific target T-cell population is enriched with a C-X-C chemokine receptor type 5 (CXCR5)+CD4+ TFH precursor phenotype. During onset of islet autoimmunity, the frequency of TFH precursors was controlled by high expression of microRNA92a (miRNA92a). miRNA92a-mediated TFH precursor induction was regulated by phosphatase and tension homolog (PTEN) - phosphoinositol-3-kinase (PI3K) signaling involving PTEN and forkhead box protein O1 (Foxo1), supporting autoantibody generation and triggering the onset of islet autoimmunity. Moreover, we identify Krueppel-like factor 2 (KLF2) as a target of miRNA92a in regulating human TFH precursor induction. Importantly, a miRNA92a antagomir completely blocked induction of human TFH precursors in vitro. More importantly, in vivo application of a miRNA92a antagomir to nonobese diabetic (NOD) mice with ongoing islet autoimmunity resulted in a significant reduction of TFH precursors in peripheral blood and pancreatic lymph nodes. Moreover, miRNA92a antagomir application reduced immune infiltration and activation in pancreata of NOD mice as well as humanized NOD Scid IL2 receptor gamma chain knockout (NSG) human leucocyte antigen (HLA)-DQ8 transgenic animals. We therefore propose that miRNA92a and the PTEN-PI3K-KLF2 signaling network could function as targets for innovative precision medicines to reduce T1D islet autoimmunity.
  • Redispersible spray-dried lipid-core nanocapsules intended for oral delivery: the influence of the particle number on redispersibility.

    Andrade, Diego Fontana de; Vukosavljevic, Branko; Benvenutti, Edilson Valmir; Pohlmann, Adriana Raffin; Guterres, Sílvia Stanisçuaski; Windbergs, Maike; Beck, Ruy Carlos Ruver; Helmholtz-Institut für pharmazeitische Forschung Saarland, Universitäzscampus E8.1, 66123 Saarbrücken, Germany. (2017-11-20)
    This study proposes a new approach to produce easily redispersible spray-dried lipid-core nanocapsules (LNC) intended for oral administration, evaluating the influence of the particle number density of the fed sample. The proposed approach to develop redispersible spray-dried LNC formulations intended for oral route is innovative, evidencing the needing of an optimization of the initial particle number density in the liquid suspension of nanocapsules. A mixture of maltodextrin and L-leucine (90:10 w/w) was used as drying adjuvant. Dynamic light scattering, turbidimetry, determination of surface area and pore size distribution, electron microscopy and confocal Raman microscopy (CRM) were used to characterize the proposed system and to better understand the differences in the redispersion behavior. An easily aqueous redispersion of the spray-dried powder composed of maltodextrin and L-leucine (90:10 w/w) was obtained, depending on the particle number density. Their surface area decreased in the presence of LNC. CRM enabled the visualization of the spatial distribution of the different compounds in the powders affording to better understand the influence of the particle number density of the fed sample on their redispersion behavior. This study shows the need for optimizing initial particle number density in the liquid formulation to develop redispersible spray-dried LNC powders.
  • Increased survival and proliferation of the epidemic strain Mycobacterium abscessus subsp. massiliense CRM0019 in alveolar epithelial cells.

    Ribeiro, Giovanni Monteiro; Matsumoto, Cristianne Kayoko; Real, Fernando; Teixeira, Daniela; Duarte, Rafael Silva; Mortara, Renato Arruda; Leão, Sylvia Cardoso; de Souza Carvalho-Wodarz, Cristiane; Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Universitycampus E8.1, 66123 Saarbrücken, Germany. (2017-09-13)
    Outbreaks of infections caused by rapidly growing mycobacteria have been reported worldwide generally associated with medical procedures. Mycobacterium abscessus subsp. massiliense CRM0019 was obtained during an epidemic of postsurgical infections and was characterized by increased persistence in vivo. To better understand the successful survival strategies of this microorganism, we evaluated its infectivity and proliferation in macrophages (RAW and BMDM) and alveolar epithelial cells (A549). For that, we assessed the following parameters, for both M. abscessus CRM0019 as well as the reference strain M. abscessus ATCC 19977: internalization, intracellular survival for up 3 days, competence to subvert lysosome fusion and the intracellular survival after cell reinfection.
  • Barriers and motivations for non-invasive drug delivery.

    Loretz, Brigitta; Schneider-Daum, Nicole; Windbergs, Maike; Schaefer, Ulrich; Schneider, Marc; Lehr, Claus Michael; HIPS, Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus E8.1,66123 Saarbrücken, Germany. (2017-09)
  • Nanoencapsulation of a glucocorticoid improves barrier function and anti-inflammatory effect on monolayers of pulmonary epithelial cell lines.

    Rigo, Lucas A; Carvalho-Wodarz, Cristiane S; Pohlmann, Adriana R; Guterres, Silvia S; Schneider-Daum, Nicole; Lehr, Claus Michael; Beck, Ruy C R; Helmholtz-Institut für Pharmazeutische Forschung Saarland [HIPS], Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2017-05-13)
    The anti-inflammatory effect of polymeric deflazacort nanocapsules (NC-DFZ) was investigated, and possible improvement of epithelial barrier function using filter grown monolayers of A549 and Calu-3 using as models was assessed. NC prepared from poly(ε-caprolactone) (PCL) had a mean size around 200 nm, slightly negative zeta potential (∼ - 8 mV), and low polydispersity index (< 0.10). Encapsulation of DFZ had an efficiency of 85%. No cytotoxic effects were observed at particle concentration of 9.85 x 10(11) NC/ml, which was therefore chosen to evaluate the effect of NC-DFZ at 1% (w/v) of PCL and 0.5% (w/v) of DFZ on the epithelial barrier function of Calu-3 monolayers. Nanoencapsulated drug at 0.5% (w/v) increased transepithelial electrical resistance and decrease permeability of the paracellular marker sodium fluorescein, while non-encapsulated DFZ failed to improve these parameters. Moreover, NC-DFZ reduced the lipopolysaccharide (LPS) mediated secretion of the inflammatory marker IL-8. In vitro dissolution testing revealed controlled release of DFZ from nanocapsules, which may explain the improved effect of DFZ on the cells. These data suggest that nanoencapsulation of pulmonary delivered corticosteroids could be advantageous for the treatment of inflammatory conditions, such as asthma and chronic obstructive pulmonary diseases.
  • Physiological, Biochemical, and Biophysical Characterization of the Lung-Lavaged Spontaneously-Breathing Rabbit as a Model for Respiratory Distress Syndrome.

    Ricci, Francesca; Catozzi, Chiara; Murgia, Xabier; Rosa, Brenda; Amidani, Davide; Lorenzini, Luca; Bianco, Federico; Rivetti, Claudio; Catinella, Silvia; Villetti, Gino; Civelli, Maurizio; Pioselli, Barbara; Dani, Carlo; Salomone, Fabrizio; Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2017)
    Nasal continuous positive airway pressure (nCPAP) is a widely accepted technique of non-invasive respiratory support in spontaneously-breathing premature infants with respiratory distress syndrome (RDS). Surfactant administration techniques compatible with nCPAP ventilation strategy are actively investigated. Our aim is to set up and validate a respiratory distress animal model that can be managed on nCPAP suitable for surfactant administration techniques studies. Surfactant depletion was induced by bronchoalveolar lavages (BALs) on 18 adult rabbits. Full depletion was assessed by surfactant component analysis on the BALs samples. Animals were randomized into two groups: Control group (nCPAP only) and InSurE group, consisting of a bolus of surfactant (Poractant alfa, 200 mg/kg) followed by nCPAP. Arterial blood gases were monitored until animal sacrifice, 3 hours post treatment. Lung mechanics were evaluated just before and after BALs, at the time of treatment, and at the end of the procedure. Surfactant phospholipids and protein analysis as well as surface tension measurements on sequential BALs confirmed the efficacy of the surfactant depletion procedure. The InSurE group showed a significant improvement of blood oxygenation and lung mechanics. On the contrary, no signs of recovery were appreciated in animals treated with just nCPAP. The surfactant-depleted adult rabbit RDS model proved to be a valuable and efficient preclinical tool for mimicking the clinical scenario of preterm infants affected by mild/moderate RDS who spontaneously breathe and do not require mechanical ventilation. This population is of particular interest as potential target for the non-invasive administration of surfactant.
  • In vitro and in vivo comparison between poractant alfa and the new generation synthetic surfactant CHF5633.

    Ricci, Francesca; Murgia, Xabier; Razzetti, Roberta; Pelizzi, Nicola; Salomone, Fabrizio; Helmholtz Institut für pharmazeutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2017-02)
    CHF5633 is a new generation synthetic surfactant containing both SP-B and SP-C analogues developed for the treatment of respiratory distress syndrome. Here, the optimal dose and its performance in comparison to the animal-derived surfactant poractant alfa were investigated.

View more