Optimized and Scalable Precoating‐Free Reprogramming of Human Peripheral Blood Mononuclear Cells into iPSCs

Abstract Human disease modeling has been profoundly transformed by the introduction of human induced pluripotent stem cells (iPSCs), marking the onset of a new era. This ground‐breaking development offers a tailored framework for generating pluripotent cells from any individual, effectively enabling the development of cellular models for the study of human physiology and diseases on an unprecedented scale. Although technologies for iPSCs generation have advanced rapidly over the past two decades, protocols for reprogramming patient‐derived somatic cells into stem cells still pose a major challenge for the development of automated pipelines capable of generating iPSCs at scales that are cost‐effective, reproducible, and easy to implement. Most methods commonly rely on extracellular matrix protein mixtures or synthetic substrates to promote efficient proliferation of iPSCs. Nonetheless, employing these substances entails a laborious and time‐consuming process, as the culture surface requires coating treatments before cell seeding. Here we describe a method for reprogramming blood‐derived mononucleated cells that eliminates the need to precoat culture surfaces for the entire experimental flow. This procedure is suitable for fresh or frozen purified peripheral blood mononuclear cells (PBMCs) and allows seeding of reprogrammed cells in a culture medium containing a fragment of laminin‐511, regardless of the method of reprogramming employed. Our protocol incorporates a streamlined workflow that optimizes key factors, including cell density, culture medium composition, and iPSC culture propagation techniques. Using a precoating‐free approach, we eliminate the time‐consuming steps, while our optimized subcloning method improves the scalability of the protocol, making it suitable for large‐scale applications. Additionally, the automation‐friendly nature of our protocol allows for high‐throughput processing, reducing the labor and costs associated with manual handling. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1 : Miniaturized and time efficient precoating‐free reprogramming of fresh or frozen PBMCs Alternate Protocol : Erythroid progenitor cells (EPCs) enrichment and reprogramming into iPSCs using Sendai viral vectors Basic Protocol 2 : Picking and precoating‐free optimized expansion of iPSC clones