Large, Stratified, and Mechanically Functional Human Cartilage Grown In Vitro by Mesenchymal Condensation Researchers report that clinically sized pieces of human cartilage with physiologic stratification and biomechanics can be grown in vitro by recapitulating some aspects of the developmental process of mesenchymal condensation. [Proc Natl Acad Sci USA] Abstract | Press Release Altered Bone Material Properties in HLA-B27 Rats Include Reduced Mineral to Matrix Ratio and Altered Collagen Cross-Links Investigators determined that in the HLA-B27 rat, an animal susceptible to both alveolar bone loss (ABL) and long bone osteopenia, there is a statistically significant negative correlation between ABL and long bone BMD, as well as mineral/matrix ratio at actively bone forming trabecular surfaces [J Bone Miner Res] Abstract Cardiac Differentiation of Cardiosphere-Derived Cells in Scaffolds Mimicking Morphology of the Cardiac Extracellular Matrix Towards elucidating the relationship between extracellular matrix (ECM) properties and cardiac differentiation, researchers created an in vitro model based on ECM-mimicking fibers and a type of cardiac progenitor cell, cardiosphere-derived cells. [Acta Biomater] Abstract Cationic Surface Charge Combined with Either Vitronectin or Laminin Dictates the Evolution of hESC/Microcarrier Aggregates and Cell Growth in Agitated Cultures Scientists describe an innovative technology, consisting of a cationic charge that underlies the extracellular matrix (ECM) coatings. By combining poly-L-lysine with a coating of ECM protein, cell attachment efficiency and cell spreading are improved, thus enabling seeding under agitation in a serum-free medium. [Stem Cells Dev] Abstract Sub-Toxic Nicotine Concentrations Affect Extracellular Matrix and Growth Factor Signaling Gene Expressions in Human Osteoblasts Investigators examined the effects of exposure to a single or multiple sub-toxic nicotine concentrations on human osteoblasts. Cell growth and expression of genes involved in bone differentiation, extracellular matrix metabolism, and growth factor signaling pathways were investigated in nicotine-treated cells compared to untreated cells. [J Cell Physiol] Abstract Novel Collagen Membranes for the Reconstruction of the Corneal Surface Investigators analyzed the suitability and biocompatibility of defined noncross-linked and UV/riboflavin cross-linked equine type I collagen membranes for the reconstruction of the corneal surface. [Tissue Eng Part A] Abstract Decreased Proliferative Capacity of Aged Dermal Fibroblasts in a Three Dimensional Matrix Is Associated with Reduced IGF1R Expression and Activation Scientists determined if expression and activation of IGF1R in aged human dermal fibroblasts, when compared to young fibroblasts, is associated with altered proliferative capacity in a 3D collagen matrix that better simulates the dermal extracellular matrix in vivo. [Biogerontology] Abstract Osteochondral Regeneration Using an Oriented Nanofiber Yarn-Collagen Type I/Hyaluronate Hybrid/TCP Biphasic Scaffold An oriented poly(L-lactic acid)-co-poly(ε-caprolactone)/collagen type I (Col-I) nanofiber yarn mesh, fabricated by dynamic liquid electrospinning served as a skeleton for a freeze-dried Col-I/hyaluronate (HA) chondral phase to enhance the mechanical strength of the scaffold. In vitro results show that the Yarn Col-I/HA hybrid scaffold can allow the cell infiltration like sponge scaffolds. [J Biomed Mater Res A] Abstract Photopolymerizable Chitosan-Collagen Hydrogels for Bone Tissue Engineering Researchers developed a composite hydrogel consisting of photocrosslinkable methacrylated glycol chitosan and semi-interpenetrating collagen with a riboflavin photoinitiator under blue light. [J Tissue Eng Regen Med] Abstract |