Efecto de células alimentadoras inactivadas de dos segmentos del oviducto en el desarrollo in vitro de embriones bovinos

The aim of this study was to evaluate the effect of inactivated feeder cells (feeder layer system) from two segments of the bovine oviduct (isthmus and ampulla) in the in vitro development of bovine embryos. Cell lines from segments of the isthmus and ampulla were generated and subsequently inactivated with mitomycin C (40 μg/ml) to inhibit their ability to divide and eliminate competition for nutrients with embryos. Bovine oocytes were matured in vitro for 24 h and were fertilized for 18 h in conventional culture with Brangus bovine semen. The expected fertilized oocytes were cultured for seven days in the feeder layer system with isthmus and ampulla cells separately at a concentration of 1.44 x 10 5 cells/ml. The best results in the production of in vitro bovine embryos were obtained with ampullary cells (280/84, 30%) in comparison with the isthmus cells (278/75, 26.9%) and the control group (275/73, 26.5%) in a conventional system. It is concluded that the cells of the oviduct can fulfill functions like those that the oviduct fulfills in the in vivo process, improving the in vitro production of embryos.El objetivo del estudio fue evaluar el efecto de células alimentadoras inactivadas (sistema feeder layer) provenientes de dos segmentos del oviducto bovino (istmo y ámpula) en el desarrollo in vitro de embriones bovinos. Se generaron líneas celulares de segmentos del istmo y ámpula para posteriormente ser inactivadas con mitomicina C (40 µg/ml) para inhibir su capacidad de división y eliminar la competencia por nutrientes con los embriones. Se maduraron in vitro ovocitos bovinos por 24 h y fueron fertilizados por 18 h en cultivo convencional con semen bovino Brangus. Los ovocitos supuestamente fertilizados fueron cultivados por siete días en el sistema feeder layer con células de istmo y ámpula separadamente a una concentración de 1.44 x 105 células/ml. Se obtuvo mejores resultados de producción de embriones bovinos in vitro con células ampulares (280/84; 30%) en comparación con las células del istmo (278/75; 26.9%) y el grupo control (275/73; 26.5%) realizado en un sistema convencional. Se concluye que las células del oviducto pueden cumplir funciones similares a las que cumple el oviducto en el proceso in vivo, mejorando la producción in vitro de embriones

The use of somatic cell nuclear transfer to obtain interspecific cloned embryos from brown brocket deer karyoplast and bovine cytoplast: Embryo development and nuclear gene expression

abstract: The brown brocket deer is a species of neotropical deer that is found in several regions of Brazil. Although not considered an endangered species, it can be used as a model for studies with somatic cell nuclear transfer (SCNT) in endangered species. Thus, this study aimed to verify the embryo development and nuclear gene expression in intraSCNT (bovine-bovine), interSCNT (deer-bovine) and in vitro fertilized (IVF) bovine embryos. Thus, from a culture of brown brocket deer fibroblasts and enucleated bovine oocytes, inter and intraspecific embryos were produced. In addition, a group of IVF bovine embryos was prepared. Quantitative PCR (qPCR) was performed from the blastocysts obtained from each experimental group to analyze the expression of OCT4, T-FAM, GJA1, BAX and BCL2. The blastocyst rate was higher (P  0.05) among experimental groups. In conclusion, bovine cytoplast was able to reprogram the brown brocket deer karyoplast and these cloned embryos were able to reach the blastocyst stage. The inverse relationship for BAX and BCL2 can indicate a high degree of apoptosis in blastocysts from interSCNT