title: Extra-embryonic human Wharton's jelly stem cells do not induce tumorigenesis, unlike human embryonic stem cells.
abstract: Tumorigenesis is the major obstacle of tissues derived from human embryonic stem cells (ESC) and human induced pluripotent stem cell (IPSC) for transplantation therapy. This prompted a search for other sources of ESC. This study isolated and characterized stem cells from the extra-embryonic human umbilical cord Wharton's jelly (WJSC). These cells are non-controversial, available in abundance, proliferative, multipotent and hypoimmunogenic. However, their tumorigenic potential has not been properly addressed. Their tumour-producing capabilities were compared with human ESC using the immunodeficient mouse model. Unlabelled human ESC+matrigel (2×10(6)cells/site), labelled human WJSC (red fluorescent protein; 5×10(6)cells/site) and unlabelled human WJSC+matrigel (5×10(6)cells/site) were injected via three routes (s.c., i.m. and i.p.). Animals that received human ESC+matrigel developed teratomas in 6 weeks (s.c. 85%; i.m. 75%; i.p. 100%) that contained tissues of ectoderm, mesoderm and endoderm. No animal that received human WJSC developed tumours or inflammatory reactions at the injection sites when maintained for a prolonged period (20 weeks). Human WJSC produced increases in anti-inflammatory cytokines in contrast to human ESC, which increased pro-inflammatory cytokines. Human WJSC, being hypoimmunogenic and non-tumorigenic, have the potential for safe cell-based therapies.
authors.affiliation: Department of Obstetrics and Gynaecology, National University of Singapore, Singapore, Singapore.
authors.forename: Kalamegam
authors.initials: K
authors.lastname: Gauthaman
authors.forename: Chui-Yee
authors.initials: CY
authors.lastname: Fong
authors.forename: Cheyyatraivendran-Arularasu
authors.initials: CA
authors.lastname: Suganya
authors.forename: Arjunan
authors.initials: A
authors.lastname: Subramanian
authors.forename: Arijit
authors.initials: A
authors.lastname: Biswas
authors.forename: Mahesh
authors.initials: M
authors.lastname: Choolani
authors.forename: Ariff
authors.initials: A
authors.lastname: Bongso
mesh_terms: D000818:Animals; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000378:metabolism*; D016207:Cytokines / Q000097:blood; D053595:Embryonic Stem Cells / Q000378:metabolism; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular; D007274:Injections, Intraperitoneal; D007279:Injections, Subcutaneous; D007378:Interleukins / Q000096:biosynthesis; D051379:Mice; D016513:Mice, SCID; D039902:Multipotent Stem Cells / Q000166:cytology* / Q000502:physiology; D059631:Wharton Jelly / Q000166:cytology*
chemical_list: D016207:Cytokines; D007378:Interleukins