Clonación de células embrionales humanas

Human Embryonic Stem Cells Derived by Somatic Cell Nuclear Transfer

Aquí les facilito el "abstract" de una investigación fundamental llevada a cabo por un nutrido grupo de estudiosos. Hasta ahora todos los intentos  de clonar células humanas habían sido infructuosos. De modo muy siplificado lo que hacen los científicos es reprogramar células ya diferenciadas, es decir somáticas, con una determinada función, en células pluripotenciales, aptas para asumir nuevas funciones. La técnica pasa por la transferencia nuclear (ver esquema). Es un paso  significativo para lograr terapias individuales (el paciente recibe sus propias células). Esperemos que una correcta información a los ciudadanos/as conjure los fantasmas retrógrados que ven una amenaza en cualquier avance científico. El presente experimento no va contra la dignidad del ser humano. Ni vulnera su integridad.

Masahito Tachibana¹, Paula Amato², Michelle Sparman¹, Nuria Marti Gutierrez¹, Rebecca Tippner-Hedges¹, Hong Ma¹, Eunju Kang¹, Alimujiang Fulati¹, Hyo-Sang Lee^{1, 6}, Hathaitip Sritanaudomchai³, Keith Masterson², Janine Larson², Deborah Eaton², Karen Sadler-Fredd², David Battaglia², David Lee², Diana Wu², Jeffrey Jensen^{1, 4}, Phillip Patton², Sumita Gokhale⁵, Richard L. Stouffer^{1, 2}, Don Wolf¹ and Shoukhrat Mitalipov^{1, 2, ,}

¹ Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, 505 NW 185th Avenue, Beaverton, OR 97006, USA
² Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
³ Department of Oral Biology, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand
⁴ Womens Health Research Unit, Oregon Health & Science University, 3303 SW Bond Avenue, Portland, OR 79239, USA
⁵ Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA

Corresponding author

⁶ Present address: Laboratory Animal Center, Osong Medical Innovation Foundation, Chungbuk 363-951, Republic of Korea

Graphical Abstract

• Summary

• Reprogramming somatic cells into pluripotent embryonic stem cells (ESCs) by somatic cell nuclear transfer (SCNT) has been envisioned as an approach for generating patient-matched nuclear transfer (NT)-ESCs for studies of disease mechanisms and for developing specific therapies. Past attempts to produce human NT-ESCs have failed secondary to early embryonic arrest of SCNT embryos. Here, we identified premature exit from meiosis in human oocytes and suboptimal activation as key factors that are responsible for these outcomes. Optimized SCNT approaches designed to circumvent these limitations allowed derivation of human NT-ESCs. When applied to premium quality human oocytes, NT-ESC lines were derived from as few as two oocytes. NT-ESCs displayed normal diploid karyotypes and inherited their nuclear genome exclusively from parental somatic cells. Gene expression and differentiation profiles in human NT-ESCs were similar to embryo-derived ESCs, suggesting efficient reprogramming of somatic cells to a pluripotent state.