P075 OCT4B1, a spliced variant of OCT4, is expressed in Inflammatory Bowel Disease
G. Karamanolis*1, M. Maragkoudaki2, A. Vaiopoulou3, G. Theodoropoulos4, M. Gazouli3
1Athens Medical School, Gastroenterology Unit, 2nd Surgical Department, Athens, Greece, 2"Aghia Sofia" Children's Hospital, University of Athens, Paediatric , Athens, Greece, 3Athens Medical School, 3Department of Basic Medical Sciences, Laboratory of Biology, Athens, Greece, 4Athens Medical School, First Propaedeutic Surgical Department, Athens, Greece
OCT4, a POU-domain transcription factor is considered to be a key factor in maintaining the pluripotency of stem cells. Several OCT4 isoforms are differentially expressed in human pluripotent and non-pluripotent cells. Aim of our study was to identify the presence of developmentally early cells in both peripheral blood and intestinal tissue from patients with Crohn's disease (CD) and ulcerative colitis (UC).
Both blood and tissue samples were collected from 17 patients with active CD and 13 UC, as well as form 4 healthy individuals. Total RNA was extracted and cDNA was prepared. OCT4 expression and isoform determination were documented by reverse transcription-PCR and real-time PCR. SOX-2 expression levels were also examined by real-time PCR. The isoforms expressed in the studied cases were confirmed by sequencing.
In all samples, OCT4B1 isoform was expressed. OCT4B1 expression levels were higher in blood samples from CD and UC. More specifically, in blood samples OCT4B1 was expressed 6.87 ± 1.94-fold greater in CD and 3.37 ± 0.53-fold greater in UC compared with healthy controls. Similar Results were obtained in tissues samples, also. On the other hand, the mRNA levels of SOX2 were found slightly increased compared to healthy controls, in both blood and tissue samples of CD patients only.
Our Results are in agreement with previous studies, showing that OCT4 is expressed in peripheral blood in patients with CD. Developmentally early cells, such as hematopoietic stem progenitor cells (HSPCs), mesenchymal stem cells (MSCs), endothelial progenitor cells (EPCs), and very small embryonic-like stem cells (VSELs), are mobilized into peripheral blood in response to tissue/organ injury, suggesting a role of these cells in repair of damaged intestinal tract.