1 Saito Laboratory of Cell Technology, Yaita, Tochigi 329-1571 Japan
2 SPK Co., Ltd., Aizuwakamatsu, Fukushima 965-0025 Japan
3 College of Engineering, Nihon University, Koriyama, Fukushima 963-8642 Japan
4 School of Dentistry, College of Dental Medicine, Kaoshiung Medical University, 100 Shin-Chuan 1st Road, Kaohsiung, 807 Taiwan
5 Cell Engineering Division, RIKEN BioResource Center, Tsukuba, 3050074 Japan
6 Department of Biochemistry and Molecular Biology, Rutgers New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07101 USA
7 Institute of Farm Animal Genetics, Friedrich-Lo¨ffler-Institut, Mariensee, 31535 Neustadt, Germany
8 Graduate Institute of Medicine, Center of Stem Cell Research, Center of Environmental Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Rd, San Ming District, Kaohsiung, 807 Taiwan
9 Faculty of Science and Engineering, Tokushima Bunri University, Sanuki, 763-2193 Japan
10 Department of Molecular Preventive Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033 Japan