Production of transgenic cloned piglets from genetically transformed fetal fibroblasts selected by green fluorescent protein Gab sang Lee a , Hye soo Kim a , Sang hwan Hyun a , So hyun Lee a , Hyun yong Jeon a , Dong hyun Nam a , Yeon woo Jeong a , Sue Kim a , Ji hye Kim a , Jae yong Han b , Curie Ahn c , Sung keun Kang a,d , Byeong chun Lee a,d , Woo suk Hwang a,b,d, * a Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, Sillim-Dong, Kwanak-ku, Seoul 151-742, South Korea b School of Agricultural Biotechnology, Seoul National University, Sillim-Dong, Kwanak-ku, Seoul 151-742, South Korea c Department of Nephrology, Seoul National University Hospital, Seoul 110-744, Korea d The Xenotransplantation Research Center, Seoul National University Hospital, Seoul 110-744, Korea Received 19 January 2004; received in revised form 13 April 2004; accepted 19 April 2004 Abstract This study was performed to develop a system for porcine somatic cell nuclear transfer (SCNT) and to produce human erythropoietin (hEPO)-transgenic cloned piglets. Porcine fetal fibroblasts were transfected with an expression plasmid (phEPO-GFP). In Experiment 1, the effect of transfection of phEPO-GFP transgene on development of porcine SCNT embryos was investigated. Three fetal fibroblast cell lines (two male and one female) with or without transfected with phEPO-GFP trasngene were used as donor cells for SCNT. Lower fusion rates were observed in two lines of transfected cells as compared to those of the control cells. In Experiment 2, the effect was examined of elevated Ca 2+ concentration in the fusion/activation medium on development of transfected SCNT embryos. The rates of fusion and blastocyst formation were significantly increased by supplementing www.journals.elsevierhealth.com/periodicals/the Theriogenology 63 (2005) 973–991 * Corresponding author. Tel.: +82 2 880 1280; fax: +82 2 884 1902. E-mail address: hwangws@snu.ac.kr (W.s. Hwang). 0093-691X/$ – see front matter # 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.theriogenology.2004.04.017