In the field of regenerative medicine, one of the ultimate goals is to generate functioning organs from pluripotent cells, such as ES cells or induced pluripotent stem cells (PSCs). We have recently generated functional pancreas and kidney from PSCs in pancreatogenesis-or nephrogenesis-disabled mice, providing proof of principle for organogenesis from PSCs in an embryo unable to form a specific organ. Key when applying the principles of in vivo generation to human organs is compensation for an empty developmental niche in large nonrodent mammals. Here, we show that the blastocyst complementation system can be applied in the pig using somatic cell cloning technology. Transgenic approaches permitted generation of porcine somatic cell cloned embryos with an apancreatic phenotype. Complementation of these embryos with allogenic blastomeres then created functioning pancreata in the vacant niches. These results clearly indicate that a missing organ can be generated from exogenous cells when functionally normal pluripotent cells chimerize a cloned dysorganogenetic embryo. The feasibility of blastocyst complementation using cloned porcine embryos allows experimentation toward the in vivo generation of functional organs from xenogenic PSCs in large animals.apancreatic pig | organ reconstitution | transplantation | somatic cell nuclear transfer | chimera

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Two experiments were conducted to investigate the effect of dietary taurine and cystine on growth and body composition of juvenile red sea bream Pagrus major. In Experiment I, a casein-based semi-purified diet included a small amount of fish meal were supplemented with taurine at the levels of 0 (control) and 1.0 %. The experimental diets in Experiment II were without fishmeal and supplemented with taurine at 0 (control), 0.5, 1.0 and 2.0 % or cystine at 1.0 and 2.0%. These diets were fed three times a day for 6 weeks to fish (average body weight: 2.3g in Experiment I and 2.5g in Experiment II). In Experiment I, fish fed the taurine supplemented diet showed significantly (P<0.05) improved growth, feed efficiency and feed consumption relative to fish fed the unsupplemental diet. The whole body taurine content increased, whereas the non-essential amino acid contents decreased, in fish fed the taurine-supplemental diet compared to fish fed the unsupplemented diet. In Experiment II, the growth, feed efficiency and feed consumption of fish fed the taurine-supplmented diets, irrespective of the dietary taurine levels, were significantly higher than those of fish fed the control diet and the cystine-supplemented diets.Taurine content in the whole body increased with the dietary taurine level, while the taurine contents did not increase by the supplemental cystine. Other free amino acid contents in the taurine supplemented diet groups followed similar trends to those in Experiment I. These results indicate that supplemental taurine to a casein-based semi-purified diet at more than 0.5% improved the growth and feed performance of juvenile red sea bream. It is also suggested that juvenile red sea bream can not metabolize cystine into taurine.3