S P E C I A L S E C T I O N
sciencemag.org SCIENCE
A P P R OX I M AT I N G
REVIEWS
Self-organization of stem cells into embryos: A window on early mammalian development p. 948
Cancer modeling meets human organoid technology p. 952
Organoids by design p. 956
Organoids-on-a-chip p. 960
946 7 JUNE 2019 • VOL 364 ISSUE 6444
Less complex than a whole organ but more representative than clusters
of cells in culture, organoids are composed of specifi c cell types that
self-organize and recapitulate various aspects of organogenesis.
As such, these 3D models enable studies of early organ devel-
opment and tissue interactions. Furthermore, when constructed
from patient-derived cells, they help us understand what happens
in the disease state, including cancer. However, organs in a dish
only approximate the real thing. They lack elements of the natu-
ral environment that are critical for infl uencing cell dynamics
and morphogenesis. In addition, multiple cell lineages may contribute
to a single organ, or physical features may be key. Hence, research-
ers are tasked with identifying and reconstructing these elements and
interactions—whether they involve coculture with other cells to gener-
ate vasculature and provide innervation, or simulation of fl uid fl ow
as with organoids-on-a-chip. These engineered biological constructs
can then more closely approximate nature’s form and function.
Continued tweaking of methods will yield exciting advances and
solve classical embryology questions surrounding the generation of
the three germ layers, breaking of symmetry, and axis formation,
and may eventually lead to the replacement of faulty body parts
though transplantation of organoid-generated tissues and organs.
By Beverly A. Purnell and Marc Lavine
ORGANS
Published by AAAS
on August 25, 2021
http://science.sciencem
ag.org/D
ownloaded from
7 JUNE 2019 • VOL 364 ISSUE 6444 947SCIENCE sciencemag.org
Lung-on-a-chip. The red and blue chambers are where airway cells are cultured to model human small airways. The device has six chambers for the generation
of six biological replicates. PHOTO: THE BIOLINES LABORATORY DIRECTED BY D. HUH AT THE UNIVERSITY OF PENNSYLVANIA
Published by AAAS
on August 25, 2021
http://science.sciencem
ag.org/D
ownloaded from
Approximating organsBeverly A. Purnell and Marc Lavine
DOI: 10.1126/science.aay1351 (6444), 946-947.364Science
ARTICLE TOOLS http://science.sciencemag.org/content/364/6444/946
CONTENTRELATED
http://stm.sciencemag.org/content/scitransmed/10/456/eaam6474.fullhttp://stm.sciencemag.org/content/scitransmed/11/478/eaau5758.fullhttp://stm.sciencemag.org/content/scitransmed/11/485/eaau7531.fullhttp://stm.sciencemag.org/content/scitransmed/11/492/eaav4523.fullhttp://science.sciencemag.org/content/sci/364/6444/960.fullhttp://science.sciencemag.org/content/sci/364/6444/956.fullhttp://science.sciencemag.org/content/sci/364/6444/952.fullhttp://science.sciencemag.org/content/sci/364/6444/948.full
PERMISSIONS http://www.sciencemag.org/help/reprints-and-permissions
Terms of ServiceUse of this article is subject to the
is a registered trademark of AAAS.ScienceScience, 1200 New York Avenue NW, Washington, DC 20005. The title (print ISSN 0036-8075; online ISSN 1095-9203) is published by the American Association for the Advancement ofScience
Science. No claim to original U.S. Government WorksCopyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of
on August 25, 2021
http://science.sciencem
ag.org/D
ownloaded from