PhD Candidate University College London (UCL) London, United Kingdom
Abstract: Fetal tissue-derived organoids are a powerful tool for modeling developing organs, studying congenital diseases and advancing translational therapies. However, ethical and legislative constraints restrict fetal tissue collection for research in several countries. The amniotic fluid (AF) can be collected through routine clinical procedures, such as amniocentesis, amniodrainage and fetal surgery, performed throughout the second and third trimester of pregnancy. Through single-cell mapping and organoid culture, our team has recently demonstrated that tissue-specific epithelial stem/progenitor cells can be isolated from the AF. These AF-derived cells consistently generate primary epithelial lung, kidney and small intestinal organoids. This study outlines a streamlined approach for establishing, characterizing and cryopreserving clonal AF-derived organoids (AFOs). This includes a rapid and cost-effective immunofluorescence method for identifying AFO’s tissue of origin. Through this approach, we derived over a thousand clonal AFO lines from 67 AF samples spanning 16 to 39 weeks of gestation including the isolation of AFOs from samples obtained at term via c-section, extending the window of applicability of our protocol. AFOs recapitulate the differentiation potential, transcriptomic profile, and functional features of their fetal tissue of origin. They also provide a unique opportunity to study fetal human epithelia during gestation, facilitating research on late human development, when tissue biopsies to derive organoids are hardly accessible. The AF offers a minimally-invasive and ethically accessible alternative to derive primary epithelial organoids from continuing pregnancies, with fewer regulatory constraints. Although restricted to the fetal epithelia, AFOs derived from the third trimester allowed to access a developmental window previously untapped. As a consequence, AFOs could find application to model congenital conditions and develop prenatal regenerative medicine strategies personalised for the fetus.
Funding Source: This work was supported by the Academy of Medical Science, UCL Therapeutic Acceleration Support, GOSH-CC, Kidney Research UK, CDH-UK, NIHR GOSH BRC and Rosetrees Trust. GD is supported by an EMBO Scientific Exchange Grant.
