• 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; et al. (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.
    • Expression and Activity of Breast Cancer Resistance Protein (BCRP/ABCG2) in Human Distal Lung Epithelial Cells In Vitro.

      Nickel, Sabrina; Selo, Mohammed Ali; Fallack, Juliane; Clerkin, Caoimhe G; Huwer, Hanno; Schneider-Daum, Nicole; Lehr, Claus Michael; Ehrhardt, Carsten; Helmholtz Institut für Pharmaceutischr Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2017-05-03)
      Breast cancer resistance protein (BCRP/ABCG2) has previously been identified with high expression levels in human lung. The subcellular localisation and functional activity of the transporter in lung epithelia, however, remains poorly investigated. The aim of this project was to study BCRP expression and activity in freshly isolated human alveolar epithelial type 2 (AT2) and type 1-like (AT1-like) cells in primary culture, and to compare these findings with data obtained from the NCI-H441 cell line.
    • Ciprofloxacin-loaded PLGA nanoparticles against Cystic Fibrosis P. aeruginosa Lung Infections.

      Günday Türeli, Nazende; Torge, Afra; Juntke, Jenny; Schwarz, Bianca C; Schneider-Daum, Nicole; Türeli, Akif Emre; Lehr, Claus-Michael; Schneider, Marc; Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2017-05-02)
      Current pulmonary treatments against Pseudomonasaeruginosa infections in cystic fibrosis (CF) lung suffer from deactivation of the drug and immobilization in thick and viscous biofilm/mucus blend, along with the general antibiotic resistance. Administration of nanoparticles (NPs) with high antibiotic load capable of penetrating the tight mesh of biofilm/mucus can be an advent to overcome the treatment bottlenecks. Biodegradable and biocompatible polymer nanoparticles efficiently loaded with ciprofloxacin complex offer a solution for emerging treatment strategies. NPs were prepared under controlled conditions by utilizing MicroJet Reactor (MJR) to yield a particle size of 190.4±28.6 nm with 0.089 PDI. Encapsulation efficiency of the drug was 79% resulting in a loading of 14%. Release was determined to be controlled and medium-independent in PBS, PBS+0.2% Tween 80 and simulated lung fluid. Cytotoxicity assays with Calu3 cells and CF bronchial epithelial cells (CFBE41o(-)) indicated that complex loaded PLGA NPs were non-toxic at concentrations >MICcipro against lab strains of the bacteria. Antibacterial activity tests revealed enhanced activity when applied as nanoparticles. NPs' colloidal stability in mucus was proven. Notably, a decrease in mucus turbidity was observed upon incubation with NPs. Herewith, ciprofloxacin complex loaded PLGA NPs are introduced as promising pulmonary nano drug delivery systems against P.aeruginosa infections in CF lung.
    • Diverse Applications of Nanomedicine.

      Pelaz, Beatriz; Alexiou, Christoph; Alvarez-Puebla, Ramon A; Alves, Frauke; Andrews, Anne M; Ashraf, Sumaira; Balogh, Lajos P; Ballerini, Laura; Bestetti, Alessandra; Brendel, Cornelia; et al. (2017-03-28)
      The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic.
    • A 3D co-culture of three human cell lines to model the inflamed intestinal mucosa for safety testing of nanomaterials.

      Susewind, Julia; de Souza Carvalho-Wodarz, Cristiane; Repnik, Urska; Collnot, Eva-Maria; Schneider-Daum, Nicole; Griffiths, Gareth Wyn; Lehr, Claus-Michael; Helmholtz-Institut für Pharmaceutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2016)
      Oral exposure to nanomaterials is a current concern, asking for innovative biological test systems to assess their safety, especially also in conditions of inflammatory disorders. Aim of this study was to develop a 3D intestinal model, consisting of Caco-2 cells and two human immune cell lines, suitable to assess nanomaterial toxicity, in either healthy or diseased conditions. Human macrophages (THP-1) and human dendritic cells (MUTZ-3) were embedded in a collagen scaffold and seeded on the apical side of transwell inserts. Caco-2 cells were seeded on top of this layer, forming a 3D model of the intestinal mucosa. Toxicity of engineered nanoparticles (NM101 TiO2, NM300 Ag, Au) was evaluated in non-inflamed and inflamed co-cultures, and also compared to non-inflamed Caco-2 monocultures. Inflammation was elicited by IL-1β, and interactions with engineered NPs were addressed by different endpoints. The 3D co-culture showed well preserved ultrastructure and significant barrier properties. Ag NPs were found to be more toxic than TiO2 or Au NPs. But once inflamed with IL-1β, the co-cultures released higher amounts of IL-8 compared to Caco-2 monocultures. However, the cytotoxicity of Ag NPs was higher in Caco-2 monocultures than in 3D co-cultures. The naturally higher IL-8 production in the co-cultures was enhanced even further by the Ag NPs. This study shows that it is possible to mimic inflamed conditions in a 3D co-culture model of the intestinal mucosa. The fact that it is based on three easily available human cell lines makes this model valuable to study the safety of nanomaterials in the context of inflammation.
    • Biodegradable starch derivatives with tunable charge density-synthesis, characterization, and transfection efficiency.

      Thiele, Carolin; Loretz, Brigitta; Lehr, Claus Michael; Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS),Saarland Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2016-10-03)
      Regioselective oxidation of water-soluble starch and conversion with alkyl diamines resulted in defined cationic starch derivatives. Those were assessed in their potential for polyplex formation, biocompatibility, and transfection efficacy. The new polymers have the advantage of being biodegradable, being not cytotoxic at rather high concentrations (LC50 > 400 μg/ml) for C2 substitution, and reach transfection efficiencies comparable to commercial transfection reagents. The polymer with the highest transfection efficacy is a C12 substituted polymer (degree of substitution = 30 %) at N/P 3. The LC50 value of that highly modified polymer is still one order of magnitude lower than that of PEI 25 kDa.
    • Lymphatic endothelial cells are a replicative niche for Mycobacterium tuberculosis.

      Lerner, Thomas R; de Souza Carvalho-Wodarz, Cristiane; Repnik, Urska; Russell, Matthew R G; Borel, Sophie; Diedrich, Collin R; Rohde, M; Wainwright, Helen; Collinson, Lucy M; Wilkinson, Robert J; et al. (2016-03-01)
      In extrapulmonary tuberculosis, the most common site of infection is within the lymphatic system, and there is growing recognition that lymphatic endothelial cells (LECs) are involved in immune function. Here, we identified LECs, which line the lymphatic vessels, as a niche for Mycobacterium tuberculosis in the lymph nodes of patients with tuberculosis. In cultured primary human LECs (hLECs), we determined that M. tuberculosis replicates both in the cytosol and within autophagosomes, but the bacteria failed to replicate when the virulence locus RD1 was deleted. Activation by IFN-γ induced a cell-autonomous response in hLECs via autophagy and NO production that restricted M. tuberculosis growth. Thus, depending on the activation status of LECs, autophagy can both promote and restrict replication. Together, these findings reveal a previously unrecognized role for hLECs and autophagy in tuberculosis pathogenesis and suggest that hLECs are a potential niche for M. tuberculosis that allows establishment of persistent infection in lymph nodes.
    • Autologous co-culture of primary human alveolar macrophages and epithelial cells for investigating aerosol medicines. Part II: evaluation of IL-10-loaded microparticles for the treatment of lung inflammation.

      Hittinger, Marius; Mell, Nico Alexander; Huwer, Hanno; Loretz, Brigitta; Schneider-Daum, Nicole; Lehr, Claus Michael; Helmholtz-Institute for Pharmaceutical Research Saarland,Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2016-09)
      Acute respiratory distress syndrome is linked to inflammatory processes in the human lung. The aim of this study was to mimic in vitro the treatment of lung inflammation by using a cell-based human autologous co-culture model. As a potential trial medication, we developed a pulmonary dry powder formulation loaded with interleukin-10 (IL-10), a potent anti-inflammatory cytokine. The inflammatory immune response was stimulated by lipopolysaccharide. The co-culture was combined with the Pharmaceutical Aerosol Deposition Device on Cell Cultures )PADDOCC), to deposit the IL-10-loaded microparticles on the inflamed co-culture model at the air-liquid interface. This treatment significantly reduced the secretion of interleukin-6 and tumour necrosis factor, as compared to the deposition of placebo (unloaded) particles. Our results show that the alveolar co-culture model, in combination with a deposition device such as the PADDOCC, may serve as a powerful tool for testing the safety and efficacy of dry powder formulations for pulmonary drug delivery.
    • Autologous co-culture of primary human alveolar macrophages and epithelial cells for investigating aerosol medicines. Part I: model characterisation.

      Hittinger, Marius; Janke, Julia; Huwer, Hanno; Scherließ, Regina; Schneider-Daum, Nicole; Lehr, Claus Michael; Helmholtz-Institute for Pharmaceutical Research Saarland,Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2016-09)
      The development of new formulations for pulmonary drug delivery is a challenge on its own. New in vitro models which address the lung are aimed at predicting and optimising the quality, efficacy and safety of inhaled drugs, to facilitate the more rapid translation of such products into the clinic. Reducing the complexity of the in vivo situation requires that such models reproducibly reflect essential physiological factors in vitro. The choice of cell types, culture conditions and the experimental set-up, can affect the outcome and the relevance of a study. In the alveolar space of the lung, epithelial cells and alveolar macrophages are the most important cell types, forming an efficient cellular barrier to aerosols. Our aim was to mimic this barrier with primary human alveolar cells. Cell densities of alveolar macrophages and epithelial cells, isolated from the same human donor, were optimised, with a focus on barrier properties. The combination of 300,000 epithelial cells/cm² together with 100,000 macrophages/cm² showed a functional barrier (transepithelial electrical resistance > 500Ω.cm²). This cell model was combined with the Pharmaceutical Aerosol Deposition Device on Cell Cultures. The functionality of the in vitro system was investigated with spray-dried fluorescently labelled poly(lactic-co-glycolic) acid particles loaded with ovalbumin as a model drug.
    • Three-dimensional hierarchical cultivation of human skin cells on bio-adaptive hybrid fibers.

      Planz, Viktoria; Seif, Salem; Atchison, Jennifer S; Vukosavljevic, Branko; Sparenberg, Lisa; Kroner, Elmar; Windbergs, Maike; Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS),Saarland, Universitätscampus E8.1, 66123 Saarbrücken, Germany. (2016-07-11)
      The human skin comprises a complex multi-scale layered structure with hierarchical organization of different cells within the extracellular matrix (ECM). This supportive fiber-reinforced structure provides a dynamically changing microenvironment with specific topographical, mechanical and biochemical cell recognition sites to facilitate cell attachment and proliferation. Current advances in developing artificial matrices for cultivation of human cells concentrate on surface functionalizing of biocompatible materials with different biomolecules like growth factors to enhance cell attachment. However, an often neglected aspect for efficient modulation of cell-matrix interactions is posed by the mechanical characteristics of such artificial matrices. To address this issue, we fabricated biocompatible hybrid fibers simulating the complex biomechanical characteristics of native ECM in human skin. Subsequently, we analyzed interactions of such fibers with human skin cells focusing on the identification of key fiber characteristics for optimized cell-matrix interactions. We successfully identified the mediating effect of bio-adaptive elasto-plastic stiffness paired with hydrophilic surface properties as key factors for cell attachment and proliferation, thus elucidating the synergistic role of these parameters to induce cellular responses. Co-cultivation of fibroblasts and keratinocytes on such fiber mats representing the specific cells in dermis and epidermis resulted in a hierarchical organization of dermal and epidermal tissue layers. In addition, terminal differentiation of keratinocytes at the air interface was observed. These findings provide valuable new insights into cell behaviour in three-dimensional structures and cell-material interactions which can be used for rational development of bio-inspired functional materials for advanced biomedical applications.
    • Calcium Phosphate System for Gene Delivery: Historical Background and Emerging Opportunities.

      Mostaghaci, Babak; Loretz, Brigitta; Lehr, Claus-Michael; Helmholtz Institut f?r Pharmazeutische Forschung Saarland, Universit?tscampus E8.1, 66123 Saarbr?cken, Germany. (2016)
      Calcium phosphate system has been used widely in in vitro gene delivery for almost four decades. Excellent biocompatibility and simple application have motivated the researchers to always consider this system in their transfection experiments. However, there was a major drawback regarding the low transfection efficiency of calcium phosphate. Hence, there have been many efforts in order to increase the gene delivery potential of this system. In this paper, the application of calcium phosphate in gene delivery is introduced. Moreover, the recent progresses in the application of calcium phosphate in the delivery of (oligo)nucleotides and different approaches to improve the properties of this system are reviewed.
    • Synthesis of a deuterated probe for the confocal Raman microscopy imaging of squalenoyl nanomedicines

      Buchy, Eric; Vukosavljevic, Branko; Windbergs, Maike; Sobot, Dunja; Dejean, Camille; Mura, Simona; Couvreur, Patrick; Desmaële, Didier; Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1,56123 Saarbrücken, Germany. (2016-06-06)
    • Non-animal models of epithelial barriers (skin, intestine and lung) in research, industrial applications and regulatory toxicology.

      Gordon, Sarah; Daneshian, Mardas; Bouwstra, Joke; Caloni, Francesca; Constant, Samuel; Davies, Donna E; Dandekar, Gudrun; Guzman, Carlos A; Fabian, Eric; Haltner, Eleonore; et al. (2015)
      Models of the outer epithelia of the human body - namely the skin, the intestine and the lung - have found valid applications in both research and industrial settings as attractive alternatives to animal testing. A variety of approaches to model these barriers are currently employed in such fields, ranging from the utilization of ex vivo tissue to reconstructed in vitro models, and further to chip-based technologies, synthetic membrane systems and, of increasing current interest, in silico modeling approaches. An international group of experts in the field of epithelial barriers was convened from academia, industry and regulatory bodies to present both the current state of the art of non-animal models of the skin, intestinal and pulmonary barriers in their various fields of application, and to discuss research-based, industry-driven and regulatory-relevant future directions for both the development of new models and the refinement of existing test methods. Issues of model relevance and preference, validation and standardization, acceptance, and the need for simplicity versus complexity were focal themes of the discussions. The outcomes of workshop presentations and discussions, in relation to both current status and future directions in the utilization and development of epithelial barrier models, are presented by the attending experts in the current report.
    • Different macro- and micro-rheological properties of native porcine respiratory and intestinal mucus.

      Bokkasam, Harish; Ernst, Matthias; Guenther, Marco; Wagner, Christian; Schaefer, Ulrich F; Lehr, Claus-Michael; Helmholtz-Institut für pharmazeutische Forschung Saarland, Universitätscampus E8.1, 66123 Saarbrücken. (2016-06-13)
      Aim of this study was to investigate the similarities and differences at macro- and microscale in the viscoelastic properties of mucus that covers the epithelia of the intestinal and respiratory tract. Natural mucus was collected from pulmonary and intestinal regions of healthy pigs. Macro-rheological investigations were carried out through conventional plate-plate rheometry. Microrheology was investigated using optical tweezers. Our data revealed significant differences both in macro- and micro-rheological properties between respiratory and intestinal mucus.
    • Impact of PEG and PEG-b-PAGE modified PLGA on nanoparticle formation, protein loading and release.

      Rietscher, René; Czaplewska, Justyna A; Majdanski, Tobias C; Gottschaldt, Michael; Schubert, Ulrich S; Schneider, Marc; Lehr, Claus-Michael (2016-03-16)
      The effect of modifying the well-established pharmaceutical polymer PLGA by different PEG-containing block-copolymers on the preparation of ovalbumin (OVA) loaded PLGA nanoparticles (NPs) was studied. The used polymers contained poly(d,l-lactic-co-glycolic acid) (PLGA), polyethylene glycol (PEG) and poly(allyl glycidyl ether) (PAGE) as building blocks. The double emulsion technique yielded spherical NPs in the size range from 170 to 220nm (PDI<0.15) for all the differently modified polymers, allowing to directly compare protein loading of and release. PEGylation is usually believed to increase the hydrophilic character of produced particles, favoring encapsulation of hydrophilic substances. However, in this study simple PEGylation of PLGA had only a slight effect on protein release. In contrast, incorporating a PAGE block between the PEG and PLGA units, also eventually enabling active targeting introducing a reactive group, led to a significantly higher loading (+25%) and release rate (+100%), compared to PLGA and PEG-b-PLGA NPs.
    • Characterization of Microvesicles Released from Human Red Blood Cells.

      Nguyen, Duc Bach; Thuy Ly, Thi Bich; Wesseling, Mauro Carlos; Hittinger, Marius; Torge, Afra; Devitt, Andrew; Perrie, Yvonne; Bernhardt, Ingolf; Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS),Saarland 9 University, 66123 Saarbrücken, Germany. (2016)
      Extracellular vesicles (EVs) are spherical fragments of cell membrane released from various cell types under physiological as well as pathological conditions. Based on their size and origin, EVs are classified as exosome, microvesicles (MVs) and apoptotic bodies. Recently, the release of MVs from human red blood cells (RBCs) under different conditions has been reported. MVs are released by outward budding and fission of the plasma membrane. However, the outward budding process itself, the release of MVs and the physical properties of these MVs have not been well investigated. The aim of this study is to investigate the formation process, isolation and characterization of MVs released from RBCs under conditions of stimulating Ca2+ uptake and activation of protein kinase C.
    • Human alveolar epithelial cells expressing tight junctions to model the air-blood barrier.

      Kuehn, Anna; Kletting, Stephanie; de Souza Carvalho-Wodarz, Cristiane; Repnik, Urska; Griffiths, Gareth; Fischer, Ulrike; Meese, Eckart; Huwer, Hanno; Wirth, Dagmar; May, Tobias; et al. (2016-03-17)
      This paper describes a new human alveolar epithelial cell line (hAELVi - human Alveolar Epithelial Lentivirus immortalized) with type I-like characteristics and functional tight junctions, suitable to model the air-blood barrier of the peripheral lung. Primary human alveolar epithelial cells were immortalized by a novel regimen, grown as monolayers on permeable filter supports and characterized morphologically, biochemically and biophysically. hAELVi cells maintain the capacity to form tight intercellular junctions, with high trans-epithelial electrical resistance (> 1000 Ω*cm²). The cells could be kept in culture over several days, up to passage 75, under liquid-liquid as well as air-liquid conditions. Ultrastructural analysis and real time PCR revealed type I-like cell properties, such as the presence of caveolae, expression of caveolin-1, and absence of surfactant protein C. Accounting for the barrier properties, inter-digitations sealed with tight junctions and desmosomes were also observed. Low permeability of the hydrophilic marker sodium fluorescein confirmed the suitability of hAELVi cells for in vitro transport studies across the alveolar epithelium. These results suggest that hAELVi cells reflect the essential features of the air-blood barrier, as needed for an alternative to animal testing to study absorption and toxicity of inhaled drugs, chemicals and nanomaterials.
    • Enhanced uptake and siRNA-mediated knockdown of a biologically relevant gene using cyclodextrin polyrotaxane

      Dandekar, P.; Jain, R.; Keil, M.; Loretz, B.; Koch, M.; Wenz, G.; Lehr, C.-M.; Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS),Saarland 9 University, 66123 Saarbrücken, Germany. (2015)