SUMMARY Cerebral organoids, three-dimensional cultures that model organogenesis, provide a new platform to investigate human brain development. High cost, variability and tissue heterogeneity limit their broad applications. Here we developed a miniaturized spinning bioreactor (SpinΩ) to generate forebrain-specific organoids from human iPSCs. These organoids recapitulate key features of human cortical development, including progenitor zone organization, neurogenesis, gene expression, and notably, a distinct human-specific outer radial glia cell layer. We also developed protocols for midbrain and hypothalamic organoids. Finally, we employed the forebrain organoid platform to model Zika virus (ZIKV) exposure. Quantitative analyses revealed preferential, productive infection of neural progenitors with either African or Asian ZIKV strains. ZIKV infection leads to increased cell death and reduced proliferation, resulting in decreased neuronal cell layer volume resembling microcephaly. Together, our brain region-specific organoids and SpinΩ provide an accessible and versatile platform for modeling human brain development and disease, and for compound testing including potential ZIKV antiviral drugs.

Battery-free, wireless microfluidic/electronic system for multiparameter sweat analysis.

Sweat is a largely unexplored biofluid that contains many important biomarkers ranging from electrolytes and metabolites to proteins, cytokines, antigens, and exogenous drugs. The eccrine and apocrine glands produce and excrete sweat through microscale pores on the epidermal surface, offering a noninvasive means for capturing and probing biomarkers that reflect hydration state, fatigue, nutrition, and physiological changes. Recent advances in skin-interfaced wearable sensors capable of real-time in situ sweat collection and analytics provide capabilities for continuous biochemical monitoring in an ambulatory mode of operation. This review presents a broad overview of sweat-based biochemical sensor technologies with an emphasis on enabling materials, designs, and target analytes of interest. The article concludes with a summary of challenges and opportunities for researchers and clinicians in this swiftly growing field.