RESUMO
Interferons (IFNs) are commonly grouped into type I and type II IFN. Type I IFNs are known as antiviral IFNs including IFN-α, IFN-ß, and IFN-ω whereas type II IFN is referred to immune IFN and IFN-γ is only member of the type II IFN. Type I IFNs are induced by virus invading however type II IFN is produced by mitogenic or antigenic stimuli. IFN-τ was first identified in ruminant ungulates as a pregnancy recognition hormone, trophoblastin. IFN-τ constitutes a new class of type I IFN, which possesses the common features of type I IFN, such as the ability to prevent viral infection and to limit cell proliferation. In addition, IFN-τ is unique in that it is induced by pregnancy unlike other type I IFNs. We cloned Bos taurus (B. T.) Coreanae IFN-τ from peripheral blood mononuclear cells. The amino acid sequence of B. T. Coreanae IFN-τ shares only 90.3% identity with that of Holstein dairy cow. Recombinant B. T. Coreanae and Holstein IFN-τ proteins were expressed in Escherichia coli and the antiviral activity of IFN-τ proteins were examined. Both recombinant proteins were active and protected human WISH and bovine MDBK cells from the cytopathic effect of vesicular stomatitis virus. The recombinant IFN-τ protein of B. T. Coreanae and Holstein properly induced the expression of antiviral genes including 2',5'-oligoadenylate synthetase (OAS) and Mx GTPase 1 (Mx-1).
Assuntos
Aminoácidos/química , Bovinos/metabolismo , Interferon Tipo I/química , Proteínas da Gravidez/química , 2',5'-Oligoadenilato Sintetase/metabolismo , Sequência de Aminoácidos , Animais , Antivirais/farmacologia , Sequência de Bases , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/imunologia , Linhagem Celular , Clonagem Molecular , Efeito Citopatogênico Viral/efeitos dos fármacos , Cães , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Interferon Tipo I/farmacologia , Dados de Sequência Molecular , Proteínas da Gravidez/genética , Proteínas da Gravidez/metabolismo , Proteínas da Gravidez/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologiaRESUMO
We examined the effects of IVM duration on rates of Korean Native Cow (KNC) first polar body extrusion, embryo development and offspring. Cumulus oocytes complexes were cultured in vitro for up to 24h. Extrusion of the first polar body was highest at 16h. At selected times during IVM, oocytes were fertilized and in vitro development was compared to blastocysts collected from superovulated KNC. After fertilization, the cleavage rate did not differ for oocytes with different durations of IVM, but the development rates of the 8-cell and blastocyst stages were significantly higher in IVM 18-h than other durations. The mean inner cell mass, trophectoderm and total cell numbers of in vivo blastocysts (40.0+/-3.8, 87.5+/-3.5 and 127.5+/-1.6, respectively) were similar to those for IVM 18-h group. When in vitro- and in vivo-derived blastocysts were transferred to Holstein heifer recipients, pregnancy and abortion rates did not differ among treatments. Mean gestation length was significantly shorter for in vivo-derived blastocysts than those derived from oocytes with 24h of IVM. Birth weight produced by the IVM 24-h group (32.0+/-2.2kg) was significantly higher than that of in vivo and IVM 18-h groups. The sex ratio of calves was similar between the in vivo and the IVM 24-h group, but all calves derived from the IVM 18-h group were males. Therefore, duration of bovine oocyte IVM played a critical role in embryo development and blastocyst cell number. In addition, it also affected birth weight and sex ratio.
