Ko, "Efficient generation of integration-free human induced pluripotent stem cells from keratinocytes by simple transfection of
episomal vectors," Stem Cells Translational Medicine, vol.
(b) Emergence of the first colonies on MEF, 11 days after the
episomal transfection.
Since the
episomal vector Pvec contains hygromycin resistance under the ubiquitous Thymidine Kinase (TK) promoter (Figure 1(a)), A11 cells survived and differentiated efficiently to neuroectodermal, endodermal, and mesodermal lineages (Supplementary Figure S2).
When retrovirus, Sendai virus, and
episomal vectors were used for iPSC generation, different reprogramming strategies were applied to obtain human iPSCs.
The addition of small molecules significantly improved
episomal reprogramming efficiency.
New World isolates have a distinct chromosomal translocation and an
episomal variation in the open reading frame (ORF) 470 DNA sequence that distinguishes them from the other isolates tested.
Life Technologies is also introducing the
Episomal iPSC Reprogramming Vectors, which leverages non-viral, non-integrating technology to deliver six genes to initiate the reprogramming of human somatic cells, such as blood and skin cells, to iPS cells.
Although T lymphocytes lack the putative EBV receptor CD21, the presence of
episomal EBV genome in T-cell lymphomas (52,53) and T lymphocytes [Yom patients with virus-associated HLH is well described (54,55).
An
episomal or lentiviral vector-mediated OCT4 expression followed by a subsequent culture of treated cells on fibronectin in commercially available MSC Medium Kit allowed the rapid and efficient programming of human CD34(+) cells directly into MSCs.
CDI produces iPSCs using a proprietary
episomal reprogramming process established by CDI founder James Thomson, Ph.D.
CDI will generate the iPSCs using the
episomal, or footprint-free, reprogramming method first developed by CDI.
In a study by Kaplan et al, (8) clonal analysis of specimens from 8 patients with PTLD--all classified as B-cell monomorphous, high-grade lymphomas--was performed using both
episomal EBV and immunoglobulin genes as markers.
Induced pluripotent stem cells (iPSCs) were obtained from foreskin fibroblast by reprogramming with
episomal vectors containing genes OCT4, SOX2, NANOG, KLF4, L-MYC, Lin28, and shRNA-p53 and the miR-302/367 cluster, along with the GFP marker (System Biosciences).
Evidence that the enterotoxin gene can be
episomal in Clostridium perfringens isolates associated with nonfood-borne human gastrointestinal diseases.
Episomal vector and Sender virus vector were once thought to be ideal nonintegrating methods, as the former works as extrachromosomal DNA in the nucleus while the latter is a method of transgene-free induction.
