Fig. 3

ES medium induced GSPCs to transform into ES-like state. a The morphology of GSPCs cultured in medium 3 for 1 passage was exhibited. b ES-like colonies appeared in GSPCs cultured in medium 3 for 3–4 passages. c ES-like colonies became dominant after a few passages. d The typical ES colonies were exhibited. e The growth curve of ES-like cells was exhibited. f The expression levels of Gfrα1, α6-integrin, Plzf, Mvh, Nanog, Sox2, Klf4, Oct4 and Gapdh were determined using RT-PCR (M. marker, (1) SSCs, (2) GSPCs, (3) ES-like cells, (4) ESCs). g Alkaline phosphatase activity was determined in ES-like cells derived from GSPCs. h ES-like cells derived from GSPCs induced teratoma in nude mice, while SSCs cultured in medium 1 could not induce teratoma. i-p IF staining assays detected the expression of pluripotent markers in ES-like cells derived from GSPCs (i, SSEA1. j, NANOG. k, DAPI. l, merge; m, CDH1. n, SOX2. o, DAPI. p, merge). q COBRA demonstrated the parental imprinting characteristics of SSCs, GSPCs and ES-like cells. r The schematic procedure of SSCs transformation into GSPCs and ES-like was summarized. Scale bar = 20 μm