Patent ID: 11920164
Assignee: YEDA RESEARCH AND DEVELOPMENT CO. LTD.
Field: Biotechnology (Chemistry)
Classification: CPC C | IPC C

Claim 0:
1. A cell culture comprising naïve human pluripotent stem cells (PSC) and a culture medium comprising about 1-300 ng/ml of LIF, about 0.05-5 μM of BIRB796, about 0.1-5 μM of CHIR99021, about 0.1-50 μM of PD032590, about 0.5-25 μM of SP600125, about 0.1-25 μM of Y27632, about 0.2-10 μM of CGP77675, about 0.1-20 ng/ml of TGFβ1 and about 0.5-10 μM of IWR1, and
wherein the culture medium is capable of maintaining the human naive PSC in a naive state for at least 5 passages, and wherein
(i) when said naive PSC is a female PSC, then said naive female PSC has two unmethylated alleles of the promoter of the X-inactive specific transcript (XIST) gene; and
(ii) when said naive PSC is a male PSC, then said naive male PSC has an unmethylated allele of said promoter of said XIST gene, and

said naive state is characterized by: ability to maintain pluripotency the absence of DNA methyltransferase 1 (DNMT1) expression as determined by OCT4 expression in an immunostaining assay; and
an expression level of transcription factor E3 (TFE3) in said naive PSC is characterized by a nucleus to cytoplasm expression ratio which is equal to or higher than 1 as determined by an immunostaining assay.