Since 2005, Cell Systems 3-D has provided expertise in the design, development and engineering of 3-D in vitro cell-tissue culture models for biomedical research in infectious diseases, cancers and evaluation of novel therapeutic agents. Their 3-D model design utilizes a variety of scaffolds within a vertically rotating wall vessel (RWV) bioreactor in combination with Synthecon, Inc., Rotating Cell Culture System (RCCS). This cell-tissue culture system technology is now recognized as valid by numerous peer-reviewed scientific publications for growing 3-D tissue analogs. RWV bioreactors were originally developed at NASA to culture cells under quiescent conditions of extremely low turbulence and low shear for space applications. It was discovered that cells grew three-dimensionally, unlike conventional monolayers. When two or more cell lines combined in the bioreactor vessels, these cells coalesced to produce tissue-like organoids. These organoids develop phenotypic aspects of in vivo tissues, such as basement membrane formation, lateral wall junctional complexes and apical polarity. Although organoids do not demonstrate complete fidelity to in vivo tissue cytoarchitecture, they do exhibit comparable functionality. Lumenal-oriented epithelial cells demonstrate microvilli and mucus secretion; microvascular endothelial cells express VEGF and Von Willibrand’s Factor and fibrocytes express laminins, proteoglycans, fibronectin and collagens, components of the basement membrane and extracellular matrix (ECM).