@conference {2280, title = {Multi-organ-on-plate system for in-vitro studies of intestinal drug absorption and hepatotoxicity}, booktitle = {ESTIV 2014}, year = {2014}, pages = {107}, address = {Egmond aan Zee, The Netherlands}, abstract = {

More meaningful in-vitro models which simulate the physiological conditions of native tissue are becoming essential in the pharmaceutical field, for early and rapid screening of drug candidates. Here, we describe a multi-organ-on-plate system based on single and double flow mini bioreactor modules for dynamic in-vitro studies of intestinal drug absorption, drug metabolism and more relevant toxicity studies. The double flow module for membrane culture was firstly characterized using computational fluid dynamic models and measurements of pressure gradients, in order to indentify the optimal flow rates for maximizing the passage of solutes through the membrane. Then, cell culture experiments were performed with fully differentiated Caco-2 cells seeded on the semi-permeable membrane as a dynamic model of the intestinal epithelium, connected to a single flow chamber with metabolically competent human upcyte{\^A}{\textregistered} hepatocytes (Medicyte GmbH, Germany) seeded on a 3D collagen cryogel. First we assessed the role of flow in modulating the passage of compounds across the epithelial barrier. Then toxicity tests were performed by administering different concentrations of hepatotoxic compounds (i.e. Diclofenac, Nimesulide, industrial nanoparticles) in the apical compartment of the MB, compared the data with cell cultures in transwells. Our results show: i) the presence of flow significantly increases translocation of all molecules tested across the membrane, ii) flow conditioned Caco-2 cells are more permeable to small hydrophilic compounds, despite having high TEER values iii) although they display higher levels of phenotypic markers (tight junctions, albumin expression etc), cells in the system are more susceptible to drug induced toxicity. In conclusion, the multi-organ-on-plate system predicts drug adsorption and toxicity better than traditional cell cultures and could be used to reduce, refine and eventually replace animal tests.

}, keywords = {Bioengineering}, author = {S. Giusti and Sbrana, T. and D. Giacopelli and V. Di Patria and A. Ahluwalia} } @conference {1803, title = {A multi-stimuli environment for cardiac tissue engineering}, booktitle = {TERMIS 3rd World Congress}, year = {2012}, address = {Vienna, Austria}, abstract = {

The identification of the ideal cell source to generate cardiac tissue able to integrate into the host myocardium and with the contractile system is crucial for cardiac engineering. Amongst different cell sources so far proposed, human adult Cardiac Progenitor Cells (hCPCs) show the ability to proliferate and differentiate toward cardiac lineages when grown in appropriate microenvironmental conditions. It is widely accepted that conventional 2D cultures may provide a physiological environment for growing cells. For this reason the need to have an engineered microenvironment, matching physiological requirements, is crucial. A 3D context with spatial and time varying distribution of regulatory factors using mechanically matched scaffolds and bioreactors could represent an in vitro cell culture model being able to more closely reflects the in vivo conditions. In the present study, the possibility of using biocompatible and biodegradable scaffolds of collagen based or derivatives hydrogels in combination with Linneg/Sca-1pos hCPCs gathered from human heart biopsies was investigated. Bio-constructs were placed in the low shear, high flow MCmB (MultiCompartment modular Bioreactor) and the combined effects of dynamic culture conditions and 3D scaffolds on cell morphology and differentiation were studied in order to investigate the possibility of fabricating stem cell-derived cardiac patches to replace infarcted tissue.

}, keywords = {Bioengineering, Bioreactors, Dynamic 3D Cultures}, author = {Tirella, A and A. Ahluwalia and P. Di Nardo and Gaudiello, E and S. Giusti and F. Pagliari} } @inbook {1286, title = {Multi-Compartmental Modular Bioreactor as Innovative System for Dynamic Cell Cultures and Co-Cultures}, booktitle = {Bioreactors: Design, Properties and Applications}, number = {978-1-62100-164-5}, year = {2011}, pages = {159 - 178}, publisher = {Nova Science Publishers, Inc}, organization = {Nova Science Publishers, Inc}, chapter = {Multi-Compartimental Modular Bioreactor as Innovative System for Dynamic Cell Cultures and Co-Cultures}, abstract = {

In this chapter, the design, fabrication process and preliminary tests of a Multi- Compartmental Modular Bioreactor used as a system for dynamic cell cultures and co-cultures is described. Although the microwell (MW) plate has become a standard in cell culture, the complexity of the physiological environment is not replicated in petri dishes or microplates. All cells are exquisitely sensitive to their micro-environment which is rich with cues from other cells and from mechanical stimuli due to flow, perfusion and movement. Microwells do not offer any form of dynamic chemical or physical stimulus to cells, such as concentration gradients, flow, pressure or mechanical stress. This is a major limitation in experiments investigating cellular responses in-vitro since the complex interplay of mechanical and biochemical factors is absent. Most researchers and industry have started to accept that classical in vitro experiments offer poor predictive value or mechanistic understanding and are shifting their interests to new technologies such as bioreactors. For this reason, a large number of bioreactor systems for cell culture have been recently designed and described. With the purpose of developing cell culture models to establish a physiological-like interaction between different cell types, a novel Multi-Compartmental Modular Bioreactor (MCmB)was realized. The modular chamber was designed with shape and dimensions similar to the 24-MultiWell allowing an easy transfer of microwell protocols. The MCmB consists of a cell culture chamber made of bio-compatible silicon polymer, with excellent self-sealing proprieties, transparency and flexibility. The modular chambers can be also connected together in series or in parallel as desired, in order to allow cell-cell cross-talk or replicate in vitro models of metabolism or diseases using allometric design principles. In this chapter we describe the bioreactor design process starting from a finite-element method (FEM) model, developed in order to study the shear stress and the oxygen concentration at the cell surface. A further version of the MCmB is also described, in which a semipermeable membrane is placed into the bioreactor allowing to create a double-chamber system (MCmB-dc) for biological barriers simulation like for example lung or intestine. Allometric methods for designing in-vitro organ models using combinations of different cell types or tissues cultured in different chambers are also presented. Allometric laws mathematically correlate non linear quantities such as organ mass, blood flow, blood retention time and metabolic rate. Using these laws the modules can be assembled in various configurations enabling organ and system physiology to be recapitulated in vitro. Preliminary experiments using the modules are also described.

}, keywords = {Bioengineering}, issn = {978-1-62100-164-5}, author = {D. Mazzei and S. Giusti and Sbrana, T. and A. Ahluwalia}, editor = {Antolli, P. G. and Zhiming Liu} }