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Recent research showed that some pluripotent stem cells were exited in umbilical cord, umbilical cord blood, amniotic fluid and peripheral blood, but research results are not consistent; Oct-4, Nanog, Sox-2, Rex-1, SSEAs as markers of embryonic stem cells, were often used in evaluation the pluripotency of stem cells. The study on expression analysis of pluripotent stem cell-related genes Oct-4, Nanog, Sox-2 and Rex-1 in human umbilical cord, umbilical cord blood and amniotic fluid by semi-quantitative RT-PCR, and analysis of these genes by homologous; Meanwhile, to test expression and distribution of Oct-4, Nanog, Sox-2, SSEA-1, SSEA-3, SSEA-4 by SP immunohistochemical method, the results were as follows:1> Oct-4, Nanog, Sox-2 and Rex-1 genes expressed stably (positive rate≥80%) in these tissues of umbilical cord, umbilical cord blood and amniotic fluid of human-derived; The expression level of the same gene in above-mentioned tissues is different, no significant difference between the expression level of umbilical cord, Middle and late amniotic fluid (P>0.05), but such is significantly higher than the expression level of umbilical cord blood (P<0.05).2、Oct-4, Nanog and Sox-2 genes expressed stably (positive rate≥80%) in the peripheral blood of different growth stages of physiological state of rhesus macaque; The expression level of the same gene in the peripheral blood of rhesus macaque was negatively correlated with ages, but that had no significant difference (P>0.05).3、Oct-4, Nanog, Sox-2 gene sequences cloned from human umbilical cord, umbilical cord blood, amniotic fluid and rhesus macaque peripheral blood homology comparison of these genes’full-length cDNA sequences from human, rhesus macaque, pig, cow, mouse, brown rat, dog, rabbit and some other species, the results showed that people and rhesus macaque, rabbits, pigs, cattle had a higher homology (75%-95.9%), even with the mice and Rattus norvegicus of the homology was ove 60%; Meanwhile, biological evolution analysis of the genes showed that the genes sequences cloned had closest relationship with the same genes sequence from human and mscaques, the three constituted a closest relationship branch; then with pigs, cattle and dogs make up of a large branch. Secondly, phylogenetic relationships followed by rabbits, rats and mice, etc.4、The positive greater than or equal (++) expression rates of markers including Oct-4, Nanog, Sox-2, SSEA-1, SSEA-3, SSEA-4 is over 75%, and no significant difference for the expression rate between two of the various factors (P>0.05), Oct-4、Nanog and Sox-2 of immunoreactive cells were mainly distributed in the human umbilical cord Wharton’s jelly and umbilical vascular around, but, few was nearby endothelial cells.
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