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nature research | reporting summary
October 2018NANOG (AF1997) antibody was validated by the manufacturer using BG01V human stem cells and embryoid body. We verified
that this antibody stains the ICM and EPIs, as expected. More than 111 citations.- PODXL (MAB1658): https://www.rndsystems.com/cn/products/human-podocalyxin-antibody-222328_mab1658
PODXL (MAB1658): antibody was validated by the manufacturer using BG01V human stem cells. We verified that this antibody
indicated the polarity of EPIs, as expected. More than 7 citations. - HLA-G (AB52455): https://www.abcam.cn/hla-g-antibody-4h84-ab52455.html
HLA-G (AB52455) antibody was validated by the manufacturer using human spleen tissue. We verified that this antibody stains
the cytoplasm of parts of TEs, as expected. More than 11 citations. - GATA6 (AF1700): https://www.rndsystems.com/cn/products/human-gata-6-antibody_af1700
GATA6 (AF1700) antibody was validated by the manufacturer using human gastric carcinoma cell line. We verified that this
antibody stains the nuclei of hypoblast, as expected. More than 29 citations. - EZRIN(E8897):https://www.sigmaaldrich.com/catalog/product/sigma/e8897?lang=zh®ion=CN
EZRIN (E8897) antibody was validated by the manufacturer using A431 cells. We verified that this antibody expressed in apical
surface in EPIs and AME, as expected. More than 40 citations. - CER1(HPA019917):https://www.sigmaaldrich.com/catalog/product/sigma/hpa019917?lang=zh®ion=CN
CER1(HPA019917) antibody was validated by the manufacturer using human small intestine. We verified that this antibody
expressed in AVE, as expected. More than 1 citations. - Phalloidin (F-actin) Alexa Fluor®488 (A12379): https://www.thermofisher.com/order/catalog/product/A12379?SID=srch-hj-
A12379
Phalloidin (F-actin) Alexa Fluor®488 (A12379) antibody was validated by the manufacturer using bovine pulmonary artery
endothelial cells and muntjac skin fibroblasts. We verified that this antibody expressed in AVE, as expected. More than 176
citations. - HESX 1 (AB246949): https://www.abcam.cn/hesx1-antibody-ab246949.html
HESX 1 (AB246949) antibody was validated by the manufacturer using human testis and skin tissue. We verified that this
antibody stains the nuclei of part of EPIs, as expected. No citations at present. - Brachyury (T) (AF2085): https://www.rndsystems.com/cn/products/human-mouse-brachyury-antibody_af2085
Brachyury (T) (AF2085) antibody was validated by the manufacturer using differentiated human embryonic stem cells and BG01V
human stem cells. We verified that this antibody stains the nuclei of posterior EPIs, as expected. More than 56 citations. - FLK-1 (KDR) (AF357): https://www.rndsystems.com/cn/products/human-vegfr2-kdr-flk-1-antibody_af357
FLK-1 (KDR) (AF357) antibody was validated by the manufacturer using human placenta and kidney tissues. We verified that this
antibody stains the extraembryonic mesoderm. More than 25 citations. - WGA Alexa Fluor® 647 (W32466): https://www.thermofisher.com/order/catalog/product/W32466?SID=srch-hj-W32466.
WGA Alexa Fluor® 647 (W32466) antibody was validated by citations using mouse cardiomyocytes on the manufacturer’s
website. We verified that this antibody expressed in apical surface in EPIs and AME. More than 4 citations.
Human research participants
Policy information about studies involving human research participants
Population characteristics All embryos collected are from the volunteers including wives and husbands who are no more than 35 years old. All volunteers
have normal chromosome karyotype and no heredity case history. The embryo donors involved in this study are fertile with at
least one healthy baby. The donors with normal body mass index are in good health. 86% couples were treated with normal IVF
and 14% couples were treated with ICSI.Recruitment Research donors in the study were recruited from The First People’s Hospital of Yunnan Province. Before giving consent, donors
have received proper counselling about the implications of the donation and potential risks. Embryos were collected with written
informed consent from the donors in this study.Ethics oversight This work was approved by the Medicine Ethics Committee of The First People’s Hospital of Yunnan Province (2017LS[K]NO.035).
The informed consent process for embryo donation complied with International Society for Stem Cell Research (ISSCR)
Guidelines for Stem Cell Research and Clinical Translation (2016) and Ethical Guidelines for Human Embryonic Stem Cell research
(2003) jointly issued by the Ministry of Science and Technology and the Ministry of Health of People’s Republic of China. The
Medicine Ethics Committee of The First People’s Hospital of Yunnan Province is composed of 9 members, including lawyers,
scientists and clinicians with relevant expertise. The Committee evaluated the scientific merit and ethical justification of this
study and conducted a full review of the donations and use of these samples. No financial inducements were offered for the
donations. In the process, couples were informed that their embryos would be used to study the developmental mechanisms of
human embryos and that their donation would not affect their IVF cycle. The culture of all embryos was terminated at day 14
post-fertilization or upon the appearance of primitive streak anlage.Note that full information on the approval of the study protocol must also be provided in the manuscript.