Three-Dimensional Biohybrid StarPEG-Heparin Hydrogel Cultures for Modeling Human Neuronal Development and Alzheimer's Disease Pathology.

In this chapter, we present the methodology currently used in our laboratory to generate a starPEG-MMP (starPEG)- and heparin maleimide HM06 (heparin)-based 3D cell culture system, in a hydrogel, that can be used to study human neuronal development and Alzheimer's disease (AD) pathology. A 3D cell culture system can mimic the in vivo cellular environment better than a 2D format, in which these cells exhibit neural network formation, electrophysiological activity, tissue-specific extracellular matrix (ECM) deposition, and neurotransmitter responsiveness. When treated with amyloid beta-42 (Aβ42) peptides, this system recapitulates many of the pathological effects of AD, including reduced neural stem cell proliferation, impaired neuronal network formation, dystrophic axonal ends, synaptic loss, failure to deposit ECM, elevated tau hyperphosphorylation, and formation of neurofibrillary tangles.

Biochemical characterization and detection of antitumor activity of l-asparaginase from thermophilic Geobacillus kaustophilus DSM 7263.

L-asparaginases, which are oncolytic enzymes, have been used in clinical applications for many years. These enzymes are also important in food processing industry due to their potential in acrylamide-mitigation. In this study, the gene for l-asparaginase (GkASN) from a thermophilic bacterium, Geobacillus kaustophilus, was cloned and expressed in E.