Programmatic introduction of parenchymal cell types into blood vessel organoids

Abstract

Pluripotent stem cell-derived organoids have transformed our ability to recreate complex three-dimensional models of human tissue. However, the directed differentiation methods used to create them do not afford the ability to introduce cross-germ-layer cell types. Here, we present a bottom-up engineering approach to building vascularized human tissue by combining genetic reprogramming with chemically directed organoid differentiation. As a proof of concept, we created neuro-vascular and myo-vascular organoids via transcription factor overexpression in vascular organoids. We comprehensively characterized neuro-vascular organoids in terms of marker gene expression and composition, and demonstrated that the organoids maintain neural and vascular function for at least 45 days in culture. Finally, we demonstrated chronic electrical stimulation of myo-vascular organoid aggregates as a potential path toward engineering mature and large-scale vascularized skeletal muscle tissue from organoids. Our approach offers a roadmap to build diverse vascularized tissues of any type derived entirely from pluripotent stem cells.

Fate and state transitions during human blood vessel organoid development

“…Hence, in order to find appropriate culture conditions for organ-specific hBVOs, one needs to first decipher the major drivers of the differences between vascular cells of different organs. Epigenetic memory needs to be taken into consideration to improve approaches which have already been applied for certain tissues, such as co-culture of PSC-derived ECs with the desired tissue (Giacomelli et al, 2017; Helle et al, 2021; Sances et al, 2018), culture in tissue-conditioned media (Puech et al, 2018), addition of small molecules (Roudnicky et al, 2020a) or synergistic overexpression of transcription factors (Dailamy et al, 2021; Roudnicky et al, 2020b). We highlight the high degree of intraorgan heterogeneity displayed by ECs, which likely governs the difference in development and severity of vascular disorders.…”

“…After mesoderm induction, vessels sprout, networks form, and subsequently develop approximate aspects of human vasculature development in vivo (Wimmer et al, 2019a). The hBVO system offers great promise for modeling human disease (Monteil et al, 2020; Wimmer et al, 2019b), and as a tool for therapy development and more accurate or complex tissue engineering (Ahn et al, 2021; Dailamy et al, 2021). However, we lack a detailed cell state atlas across hBVO development, and we do not yet understand the power and limitations of this system in order to harness its full potential.…”

Recent advancements and future requirements in vascularization of cortical organoids

“…They also reported increased BBB marker expression and significantly improved electrophysiological activity. A reverse approach was taken by Dailamy et al (2021) where iPSCs and inducible neurons were incorporated into vascular organoids and neuronal expression was induced on day 15 of vascular differentiation. This approach resulted in clusters of neural and vascular networks with some co-localization at their borders but without spanning the organoid uniformly.…”

Angiorganoid: vitalizing the organoid with blood vessels

“…In the study of building retina-on-a-chip, researchers were able to ensure the stability of the system environment by monitoring generated proteins that are crucial for the development of retinal organoids ( 43 ). For a more comprehensive summary of this area, an excellent review paper has just been published ( 45 ).…”

“…Blood vessel organoids are amenable to model physiological structures, such as the blood–brain barrier ( 25 ), or pathological models, such as diabetic microangiopathy ( 44 ), and these models can be used for drug screening. In addition, some strategies of angiorganoid also need to construct the vascular system first and then directly introduce parenchymal cells into vascular organoids ( 45 ). Kusuma et al induced iPSC to differentiate into early derivatives of the vascular lineage, which can mature into ECs and pericytes.…”