技术资料

Human intestinal organoids (HIOs) derived from pluripotent stem cells provide a valuable model for investigating human intestinal organogenesis and physiology,but they lack the immune components required to fully recapitulate the complexity of human intestinal biology and diseases. To address this issue and to begin to decipher human intestinal-immune crosstalk during development,we generated HIOs containing immune cells by transplanting HIOs under the kidney capsule of mice with a humanized immune system. We found that human immune cells temporally migrate to the mucosa and form cellular aggregates that resemble human intestinal lymphoid follicles. Moreover,after microbial exposure,epithelial microfold cells are increased in number,leading to immune cell activation determined by the secretion of IgA antibodies in the HIO lumen. This in vivo HIO system with human immune cells provides a framework for future studies on infection- or allergen-driven intestinal diseases. View Publication

BACKGROUND AND AIMS The intestinal mucosa undergoes a continual process of proliferation,differentiation,and apoptosis. An imbalance in this highly regimented process within the intestinal crypts is associated with several intestinal pathologies. Although metabolic changes are known to play a pivotal role in cell proliferation and differentiation,how glycolysis contributes to intestinal epithelial homeostasis remains to be defined. METHODS Small intestines were harvested from mice with specific hexokinase 2 (HK2) deletion in the intestinal epithelium or LGR5+ stem cells. Glycolysis was measured using the Seahorse XFe96 analyzer. Expression of phospho-p38 mitogen-activated protein kinase,the transcription factor atonal homolog 1,and intestinal cell differentiation markers lysozyme,mucin 2,and chromogranin A were determined by Western blot,quantitative real-time reverse transcription polymerase chain reaction,or immunofluorescence,and immunohistochemistry staining. RESULTS HK2 is a target gene of Wnt signaling in intestinal epithelium. HK2 knockout or inhibition of glycolysis resulted in increased numbers of Paneth,goblet,and enteroendocrine cells and decreased intestinal stem cell self-renewal. Mechanistically,HK2 knockout resulted in activation of p38 mitogen-activated protein kinase and increased expression of ATOH1; inhibition of p38 mitogen-activated protein kinase signaling attenuated the phenotypes induced by HK2 knockout in intestinal organoids. HK2 knockout significantly decreased glycolysis and lactate production in intestinal organoids; supplementation of lactate or pyruvate reversed the phenotypes induced by HK2 knockout. CONCLUSIONS Our results show that HK2 regulates intestinal stem cell self-renewal and differentiation through p38 mitogen-activated protein kinase/atonal homolog 1 signaling pathway. Our findings demonstrate an essential role for glycolysis in maintenance of intestinal stem cell function. View Publication

Sulfated glycosaminoglycans (GAGs),or synthetic mimetics thereof,are not favorably viewed as orally bioavailable drugs owing to their high number of anionic sulfate groups. Devising an approach for oral delivery of such highly sulfated molecules would be very useful. This work presents the concept that conjugating cholesterol to synthetic sulfated GAG mimetics enables oral delivery. A focused library of sulfated GAG mimetics was synthesized and found to inhibit the growth of a colorectal cancer cell line under spheroid conditions with a wide range of potencies ( 0.8 to 46). Specific analogues containing cholesterol,either alone or in combination with clinical utilized drugs,exhibited pronounced in vivo anticancer potential with intraperitoneal as well as oral administration,as assessed by ex vivo tertiary and quaternary spheroid growth,cancer stem cell (CSC) markers,and/or self-renewal factors. Overall,cholesterol derivatization of highly sulfated GAG mimetics affords an excellent approach for engineering oral activity. View Publication