Expression of intracellular interferon-alpha confers antiviral properties in transfected bovine fetal fibroblasts and does not affect the full development of SCNT embryos

Upregulation of interferon-alpha gene in bovine embryos produced in vitro in response to experimental infection with noncytophatic bovine-viral-diarrhea virus

In-vitro fertilization is a routine livestock-breeding technique widely used around the world. Several studies have reported the interaction of bovine viral-diarrhea virus (BVDV) with gametes and in-vitro-produced (IVP) bovine embryos. Since, gene expression in BVDV-infected IVP bovine embryos is scarcely addressed. The aim of this work was to evaluate the differential expression of genes involved in immune and inflammatory response. Groups of 20-25 embryos on Day 6 (morula stage) were exposed (infected) or not (control) to an NCP-BVDV strain in SOF medium. After 24 h, embryos that reached expanded blastocyst stage were washed. Total RNA of each embryo group was extracted to determine the transcription levels of 9 specific transcripts related with antiviral and inflammatory response by SYBR Green real time quantitative (RT-qPCR). Culture media and an aliquot of the last embryos wash on Day 7 were analyzed by titration and virus isolation, respectively. A conventional PCR confirmed BVDV presence in IVP embryos. A significantly higher expression of interferon-α was observed in blastocysts exposed to NCP-BVDV compared to the controls (p < 0.05). In this study, the upregulation of INFα and TLR7 genes involved in inflammatory and immune response in BVDV-infected IVP bovine embryos is a new finding in this field. This differential expression suggest that embryonic cells could function in a manner like immune cells by recognizing and responding early to interaction with viral pathogens. These results provide new insights into the action of BVDV on the complex molecular pathways controlling bovine early embryonic development.

Evolutionary Pattern of Interferon Alpha Genes in Bovidae and Genetic Diversity of IFNAA in the Bovine Genome

Interferons are secretory proteins induced in response to specific extracellular stimuli which stimulate intra- and intercellular networks for regulating innate and acquired immunity, resistance to viral infections, and normal and tumor cell survival and death. Type 1 interferons plays a major role in the CD8 T-cell response to viral infection. The genomic analysis carried out here for type I interferons within Bovidae family shows that cattle, bison, water buffalo, goat, and sheep (all Bovidae), have different number of genes of the different subtypes, with a large increase in the numbers, compared to human and mouse genomes. A phylogenetic analysis of the interferon alpha (IFNA) proteins in this group shows that the genes do not follow the evolutionary pattern of the species, but rather a cycle of duplications and deletions in the different species. In this study we also studied the genetic diversity of the bovine interferon alpha A (IFNAA), as an example of the IFNA genes in cattle, sequencing a fragment of the coding sequence in 18 breeds of cattle from Pakistan, Nigeria and USA. Similarity analysis allowed the allocation of sequences into 22 haplotypes. Bhagnari, Brangus, Sokoto Gudali, and White Fulani, had the highest number of haplotypes, while Angus, Hereford and Nari Master had the least. However, when analyzed by the average haplotype count, Angus, Bhagnari, Hereford, Holstein, Muturu showed the highest values, while Cholistani, Lohani, and Nari Master showed the lowest values. Haplotype 4 was found in the highest number of individuals (74), and in 15 breeds. Sequences for yak, bison, and water buffalo, were included within the bovine haplotypes. Medium Joining network showed that the sequences could be divided into 4 groups: one with highly similar haplotypes containing mostly Asian and African breeds, one with almost all of the Bos taurus American breeds, one mid-diverse group with mostly Asian and African sequences, and one group with highly divergent haplotypes with five N'Dama sequences and one from each of White Fulani, Dhanni, Tharparkar, and Bhagnari. The large genetic diversity found in IFNAA could be a very good indication of the genetic variation among the different genes of IFNA and could be an adaptation for these species in response to viral challenges they face.

Biological effects and clinical characteristics of microRNA-106a in human colorectal cancer

MicroRNAs serve important roles in various diseases, particularly cancer. microRNA-106a (miR-106a) exhibits abnormal expression and oncogenic activity in carcinogenesis. The clinical significance of the abnormal expression of miR-106a in colorectal cancer is poorly understood. In the present study, miR-106a expression from colorectal cancer tissues was quantified using the reverse transcription-quantitative polymerase chain reaction. The overexpression or knockdown of miR-106a was performed by transfection with microRNA mimic or inhibitor in human colorectal carcinoma HCT116 cells. The overexpression of miR-106a promoted viability and inhibited apoptosis in colorectal cancer cells. The association between miR-106a expression and clinicopathological factors was analyzed, and it was identified that miR-106a exhibited significantly increased expression in adenocarcinoma tissues compared with in mucinous carcinoma tissues, and the expression of miR-106a was identified to be associated with the depth of invasion and differentiation. The expression of miR-106a in plasma was also determined and it was identified that increased expression of miR-106a, as a characteristic of patients with colorectal cancer, may be distinguished from that of other patients by digitization of the areas under the receiver operating characteristic curves. These data suggested that miR-106a is a potential biomarker in the diagnosis of colorectal carcinoma. However, the underlying molecular mechanism of miR-106a-promoted viability and inhibition of apoptosis requires further investigation.

Effective Oocyte Vitrification and Survival Techniques for Bovine Somatic Cell Nuclear Transfer

Bovine somatic cell nuclear transfer (SCNT) using vitrified-thawed (VT) oocytes has been studied; however, the cloning efficiency of these oocytes is not comparable with that of nonvitrified (non-V) fresh oocytes. This study sought to optimize the survival and cryopreservation of VT oocytes for SCNT. Co-culture with feeder cells that had been preincubated for 15 h significantly improved the survival of VT oocytes and their in vitro developmental potential following SCNT in comparison to co-culture with feeder cells that had been preincubated for 2, 5, or 24 h (p<0.05). Spindle assessment via the Oosight Microscopy Imaging System and microtubule staining revealed that vitrified metaphase II oocytes (VT group) were not suitable for SCNT. However, enucleating and/or activating oocytes prior to freezing enhanced their developmental potential and suitability for SCNT. The cloning efficiency of the enucleated-activated-vitrified-thawed (EAVT) group (21.6%) was better than that of the other vitrification groups [enucleated-vitrified-thawed (EVT) group, 13.7%; VT group, 15.0%; p<0.05] and was comparable with that of the non-V group (25.9%). The reactive oxygen species level was significantly lower in the EAVT group than in the other vitrification groups (p<0.05). mRNA levels of maternal genes (ZAR1, BMP15, and NLRP5) and a stress gene (HSF1) were lower in the vitrification groups than in the non-V group (p<0.05), whereas the level of phospho-p44/42 mitogen-activated protein kinase did not differ among the groups. Among the vitrification groups, blastocysts in the EAVT group had the best developmental potential, as judged by their high mRNA expression of developmental potential-related genes (POU5f1, Interferon-tau, and SLC2A5) and their low expression of proapoptotic (CASP3) and stress (Hsp70) genes. This study demonstrates that SCNT using bovine frozen-thawed oocytes can be successfully achieved using optimized vitrification and co-culture techniques.