Long-term in vivo chimeric cells tracking in non-human primate.

Non-human primates (NHPs) are increasingly used in preclinical trials to test the safety and efficacy of biotechnology therapies. Nonetheless, given the ethical issues and costs associated with this model, it would be highly advantageous to use NHP cellular models in clinical studies. However, developing and maintaining the naïve state of primate pluripotent stem cells (PSCs) remains difficult as does in vivo detection of PSCs, thus limiting biotechnology application in the cynomolgus monkey. Here, we report a chemically defined, xeno-free culture system for culturing and deriving monkey PSCs in vitro. The cells display global gene expression and genome-wide hypomethylation patterns distinct from monkey-primed cells. We also found expression of signaling pathways components that may increase the potential for chimera formation. Crucially for biomedical applications, we were also able to integrate bioluminescent reporter genes into monkey PSCs and track them in chimeric embryos in vivo and in vitro. The engineered cells retained embryonic and extra-embryonic developmental potential. Meanwhile, we generated a chimeric monkey carrying bioluminescent cells, which were able to track chimeric cells for more than 2 years in living animals. Our study could have broad utility in primate stem cell engineering and in utilizing chimeric monkey models for clinical studies.

Establishment of Epithelial Inflammatory Injury Model Using Intestinal Organoid Cultures.

Intestinal epithelial dysfunction is critical in the development of inflammatory bowel disease (IBD). However, most cellular experiments related to epithelial barrier studies in IBD have been based on tumor cell line that lack a variety of intestinal epithelial cell types. Thus, intestinal organoids can present the three-dimensional structure and better simulate the physiological structure and function of the intestinal epithelium in vitro. Here, the crypts were isolated from the small intestine of mice; with the participation of major cytokines (EGF, Noggin, and R-Spondin 1 included), the intestinal organoids were established at a density of 100 crypts per well, containing intestinal stem cells (ISC), Paneth cells, goblet cells, and intestinal endocrine cells. We found that tumor necrosis factor-alpha (TNF-α) could induce the inflammatory response of intestinal organoids, and a dose of 10 ng/mL could maintain stable passaging of organoids for dynamic observation. After stimulation with TNF-α, the intestinal organoid cultures showed lower expression of the cell proliferation-related protein identified by monoclonal antibody Ki 67 (Ki67), the ISC marker leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5), and the intestinal tight junction proteins occludin (Ocln) and claudin-1 (Cldn1) while higher expression of the inflammatory cytokine interleukin- (IL-) 15 and the chemokines C-X-C motif ligand 2 (Cxcl2) and Cxcl10 significantly. In this study, we successfully established an epithelial inflammatory injury model of intestinal organoids, which provides an effective in vitro model for studying the pathogenesis and treatment of IBD.

Current state of stem cell research in non-human primates: an overview.

The remarkable similarity between non-human primates (NHPs) and humans establishes them as essential models for understanding human biology and diseases, as well as for developing novel therapeutic strategies, thereby providing more comprehensive reference data for clinical treatment. Pluripotent stem cells such as embryonic stem cells and induced pluripotent stem cells provide unprecedented opportunities for cell therapies against intractable diseases and injuries. As continue to harness the potential of these biotechnological therapies, NHPs are increasingly being employed in preclinical trials, serving as a pivotal tool to evaluate the safety and efficacy of these interventions. Here, we review the recent advancements in the fundamental research of stem cells and the progress made in studies involving NHPs.