Teratoma formation assay for analysis of pluripotency in induced pluripotent stem cells (iPS)

• Grant number: 13/06841-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2013
• End date: December 31, 2015
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Simone Kashima Haddad
• Grantee: Isabela Gerdes Gyuricza
• Host Institution: Hemocentro de Ribeirão Preto. Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da USP (HCMRP). Secretaria da Saúde (São Paulo - Estado). Ribeirão Preto , SP, Brazil

Abstract

Embryonic stem-cells (ESC) are obtained from inner cell mass of the blastocyst and are identified by the ability to generate all the tissues of grown body. The establishment of ESC inaugurated the possibility of replace disabled cells for "new" ones. Nevertheless, medical utility of ESC are restricted by ethical issues that involves the use of human embryos, causing destruction of these, and the possible immunological response from treated individual. The description of induced pluripotent stem-cells (iPS), in other words, the description of the reprogramming of a somatic cell to a phase of pluripotency by the insertion of transcription factors, transposed the roadblocks of ESC using and represented a huge advance of science. It is due to iPS avoid the destruction of human embryos and immune rejection, since the cells would be obtained from the patient, reprogrammed, and then, inserted in the same individual. To confirm the pluripotent character of an originated iPS, several tests must be performed such as, analysis of surface markers, alkaline phosphatase, in vitro spontaneous differentiation and the teratoma formation assay, the last one considered the most important evaluation methods. It consists in the injection of iPS in immunodeficient mice, aiming the observation of a benign tumor composed of tissues from the three germ layers. The purposes of this study are to test and to establish the protocol of teratoma formation assay and, then, to confirm the pluripotent character of reprogrammed cells so posterior studies become possible. (AU)