Tuyển tập các báo cáo nghiên cứu khoa học ngành y học tạp chí Medical Sciences dành cho các bạn sinh viên ngành y tham khảo đề tài: Low temperature tolerance of human embryonic stem cells. | Int. J. Med. Sci. 2006 3 124 Short research communication International Journal of Medical Sciences ISSN 1449-1907 2006 3 4 124-129 2006 Ivyspring International Publisher. All rights reserved Low temperature tolerance of human embryonic stem cells Boon Chin Heng 1 Kumar Jayaseelan Vinoth 1 Hua Liu 1 Manoor Prakash Hande 2 Tong Cao 1 1. Stem Cell Laboratory Faculty of Dentistry National University of Singapore 5 Lower Kent Ridge Road 119074 Singapore. 2. Department of Physiology Yong Loo Lin School of Medicine National University of Singapore MD9 2 Medical Drive 117597 Singapore. Correspondence to Dr. Tong Cao e-mail dencaot@ Tel 65-6516-4630 Fax 65-6774-5701 Received Accepted Published This study investigated the effects of exposing human embryonic stem cells hESC to 4oC and 25oC for extended durations of 24h and 48h respectively. Cell survivability after low temperature eXposure was assessed through the MTT assay. The results showed that hESC survivability after exposure to 25oC and 4oC for 24h was and respectively significantly different P . The corresponding survival rates after 48h exposure to 25oC and 4oC was and respectively not significantly different P . Spontaneous differentiation of hESC after low temperature exposure was assessed by morphological observations under bright-field and phase-contrast microscopy and by immunocytochemical staining for the pluripotency markers SSEA-3 and TRA-1-81. hESC colonies were assigned into 3 grades according to their degree of spontaneous differentiation 1 Grade A which was completely or mostly undifferentiated 2 Grade B which was partially differentiated and 3 Grade C which was mostly differentiated. In all low temperature exposed groups about 95 of colonies remain undifferentiated Grade A which was not significantly different P from the unexposed control group maintained at 37oC. Additionally normal karyotype .