An approach for producing transgenic cloned cows by nuclear transfer of cells transfected with human alpha 1-antitrypsin gene Goo Jang a , M.M.U. Bhuiyan a , Hyun Yong Jeon a , Kyeong Hee Ko a , Hee Jung Park a , Min Kyu Kim a , Joung Ju Kim a , Sung Keun Kang a,b , Byeong Chun Lee a,b, * , Woo Suk Hwang a,b,c a Department of Therigenology and Biotechnology, College of Veterinary Medicine, Seoul National University, San56-1, Shillim-Dong, Kwanak-Gu, Seoul 151-742, South Korea b The Xenotransplantation Research Center, Seoul National University Hospital, Seoul 110-744, South Korea c School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, South Korea Received 16 April 2005; received in revised form 12 October 2005; accepted 15 October 2005 Abstract In an attempt to produce transgenic cloned cows secreting alpha 1-antitrypsin (a1-AT) protein into milk, bovine cumulus cells were transfected with a plasmid containing an a1-AT gene and green fluorescent protein (GFP) reporter gene using Fugene 6 1 as a lipid carrier. The GFP-expressing cells were selected and transferred into enucleated bovine oocytes. Couplets were fused, chemically activated and cultured. Developmental competence was monitored and the number of inner cell mass (ICM) and trophectoderm (TE) cells in blastocysts were counted after differential staining. The percentage of blastocysts was lower (P < 0.05) in transgenic cloned embryos compared to non- transgenic cloned embryos (23% versus 35%). No difference in the numbers of ICM and TE cells between the two groups of embryos was observed. One or two GFP-expressing blastocysts were transferred into the uterus of each recipient cow. Out of 49 recipient cows, three pregnancies were detected by non-return estrus and rectal palpation. However, the pregnancies failed to maintain to term; two fetuses were aborted at Day 60 and 150, respectively, and one fetus at Day 240. The www.journals.elsevierhealth.com/periodicals/the Theriogenology 65 (2006) 1800–1812 * Corresponding author. Tel.: +82 2 880 1269; fax: +82 2 884 1902. E-mail address: bclee@snu.ac.kr (B.C. Lee). 0093-691X/$ – see front matter # 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.theriogenology.2005.10.014