State of the art in the production of transgenic goats

2004 ◽  
Vol 16 (4) ◽  
pp. 465 ◽  
Author(s):  
H. Baldassarre ◽  
B. Wang ◽  
C. L. Keefer ◽  
A. Lazaris ◽  
C. N. Karatzas

This review summarises recent advances in the field of transgenic goats for the purpose of producing recombinant proteins in their milk. Production of transgenic goats via pronuclear microinjection of DNA expression vectors has been the traditional method, but this results in low efficiencies. Somatic cell nuclear transfer has dramatically improved efficiencies in rates of transgenesis. Characterisation of transfected cells in vitro before use in nuclear transfer guarantees that kids born are transgenic and of predetermined gender. Using these platform technologies, several recombinant proteins of commercial interest have been produced, although none of them has yet gained marketing approval. Before these technologies are implemented in goat improvement programmes, efficiencies must be improved, costs reduced, and regulatory approval obtained for the marketing of food products derived from such animals.

2003 ◽  
Vol 59 (3-4) ◽  
pp. 831-839 ◽  
Author(s):  
Hernan Baldassarre ◽  
Bin Wang ◽  
Nacereddine Kafidi ◽  
Melanie Gauthier ◽  
Nathalie Neveu ◽  
...  

2002 ◽  
Vol 63 (4) ◽  
pp. 437-443 ◽  
Author(s):  
Bin Wang ◽  
H. Baldassarre ◽  
T. Tao ◽  
M. Gauthier ◽  
N. Neveu ◽  
...  

2011 ◽  
Vol 23 (1) ◽  
pp. 133
Author(s):  
Y. S. Mu ◽  
D. D. Jiang ◽  
Y. J. Huan ◽  
J. Zhu ◽  
H. Li ◽  
...  

Data from mice showed that follistatin can block myostatin activity in vivo and follistatin overexpressed in transgenic mice can induce dramatic increases in muscle mass. In order to determine whether this effect of follistatin have the same results in swine, we design experiment to make a follistatin transgenic porcine by somatic cell nuclear transfer. We hope to get a follistatin transgenic porcine that has double muscle mass. The present study aimed to construct follistatin transgenic embryos by somatic cell nuclear transfer. A follistatin (FST) expression vector, pFST-1, which contains a porcine FST cDNA (with modification of codon usage) driven by the human cytomegalovirus (CMV) promoter, was constructed. A SV40-neo expression cassette as a selection marker was inserted into pFST-1 to generate pST101, which was transfected into early-passage male primary porcine fetal fibroblast cells by the lipofection method; the transfected cells were selected with 400 mg mL–1 G418. The G418-resistant colonies were pooled. Cell genome DNA was extracted and PCR analysis showed that CMV promoter, follistatin CDS, and SV40 polyA can be detected, indicating that the expression construct had integrated in cell genome. RT-PCR analysis showed that pST101 cells contained higher amounts of FST cDNA compared with the non-transfected cells, indicating that the follistatin was overexpressed in the primary porcine cells. Then, pST101 cell as donor cell and non-transfected cells as control donor cell were used to construct somatic cell nuclear transfer (SCNT) embryos. All of these SCNT embryos were cultured in Porcine Zygote Medium-3. The cleavage rate and blastocyst rate was assessed on 48 h and Day 6. All data were subjected to a Generalized Linear Model Procedure (PROC-GLM) of Statistical Analysis System (SAS, SAS Institute Inc., Cary, NC, USA). The cleavage rate of pST101 cell and control cell derived SCNT embryos were 83.6 ± 2.0% (267/318) and 84.0 ± 2.2% (139/167) respectively, there were no significant (P > 0.05) differences between them. The blastocyst rate from pST101 cell and control cell derived SCNT embryos were 21.4 ± 1.8% (65/318) and 15.0 ± 3.0% (26/167) respectively, the SCNT embryos derived from pST101 cell showed a higher (P < 0.05) blastocyst rate. These results indicated that follistatin transgenic porcine embryo can be successfully constructed and can develop in vitro to blastocyst with a higher rate than control SCNT embryo. Further study will be focused on the full development in vivo of the transgenic embryos and phenotype of transgenic piglets. This work was supported in part by the National High-tech Research and Development Program of China (2008AA101006) and Major Projects for Transgenic Animals of China (2008ZX08006-002).


Zygote ◽  
2011 ◽  
Vol 20 (1) ◽  
pp. 67-72 ◽  
Author(s):  
So Gun Hong ◽  
Hyun Ju Oh ◽  
Jung Eun Park ◽  
Min Jung Kim ◽  
Geon A. Kim ◽  
...  

SummarySomatic cell nuclear transfer (SCNT) has emerged as an important tool for producing transgenic animals and deriving transgenic embryonic stem cells. The process of SCNT involves fusion of in vitro matured oocytes with somatic cells to make embryos that are transgenic when the nuclear donor somatic cells carry ‘foreign’ DNA and are clones when all the donor cells are genetically identical. However, in canines, it is difficult to obtain enough mature oocytes for successful SCNT due to the very low efficiency of in vitro oocyte maturation in this species that hinders canine transgenic cloning. One solution is to use oocytes from a different species or even a different genus, such as bovine oocytes, that can be matured easily in vitro. Accordingly, the aim of this study was: (1) to establish a canine fetal fibroblast line transfected with the green fluorescent protein (GFP) gene; and (2) to investigate in vitro embryonic development of canine cloned embryos derived from transgenic and non-transgenic cell lines using bovine in vitro matured oocytes. Canine fetal fibroblasts were transfected with constructs containing the GFP and puromycin resistance genes using FuGENE 6®. Viability levels of these cells were determined by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay. Interspecies SCNT (iSCNT) embryos from normal or transfected cells were produced and cultured in vitro. The MTT measurement of GFP-transfected fetal fibroblasts (mean OD = 0.25) was not significantly different from non-transfected fetal fibroblasts (mean OD = 0.35). There was no difference between transgenic iSCNT versus non-transgenic iSCNT embryos in terms of fusion rates (73.1% and 75.7%, respectively), cleavage rates (69.7% vs. 73.8%) and development to the 8–16-cell stage (40.1% vs. 42.7%). Embryos derived from the transfected cells completely expressed GFP at the 2-cell, 4-cell, and 8–16-cell stages without mosaicism. In summary, our results demonstrated that, following successful isolation of canine transgenic cells, iSCNT embryos developed to early pre-implantation stages in vitro, showing stable GFP expression. These canine–bovine iSCNT embryos can be used for further in vitro analysis of canine transgenic cells and will contribute to the production of various transgenic dogs for use as specific human disease models.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Yu-Guo Yuan ◽  
Liyou An ◽  
Baoli Yu ◽  
Shaozheng Song ◽  
Feng Zhou ◽  
...  

To improve nutrient content of goat milk, we describe the construction of a vector (pBLAC) containing a hybrid goatβ-lactoglobulin (BLG) promoter/cytomegalovirus (CMV) enhancer. We also describe the generation of transgenic goats expressing rhLA by somatic cell nuclear transfer (SCNT). Of 334 one-cell stage embryos derived from three transgenic cell lines and 99 embryos derived from non-transgenic (NT) cells surgically transferred to the oviducts of 37 recipients, two recipients delivered two kids (2%) from the non-transfected line and five recipients delivered six kids (1.8%) from transgenic cell lines, three of which died within 2 days. Compared to the NT donor cells, transfection of donor cells does not negatively affect the development of nuclear transfer embryos into viable transgenic offspring. However, the clone efficiency in cell line number 1 was lower than that in numbers 2 and 3, and in the NT lines (0.9% versus 1.9% 2.4% and 2%;P<0.05). Two transgenic cloned goats expressed rhLA in the milk at 0.1–0.9 mg/mL. The mammary gland-specific expression vector pBLAC with hybrid BLG/CMV can drive the hLA gene to expressin vitroandin vivo. These data establish the basis for use of a hybrid promoter/enhancer strategy to produce rhLA transgenic goats.


2020 ◽  
Vol 4 ◽  
pp. 239784732097975
Author(s):  
Stéphanie Boué ◽  
Didier Goedertier ◽  
Julia Hoeng ◽  
Anita Iskandar ◽  
Arkadiusz K Kuczaj ◽  
...  

E-vapor products (EVP) have become popular alternatives for cigarette smokers who would otherwise continue to smoke. EVP research is challenging and complex, mostly because of the numerous and rapidly evolving technologies and designs as well as the multiplicity of e-liquid flavors and solvents available on the market. There is an urgent need to standardize all stages of EVP assessment, from the production of a reference product to e-vapor generation methods and from physicochemical characterization methods to nonclinical and clinical exposure studies. The objective of this review is to provide a detailed description of selected experimental setups and methods for EVP aerosol generation and collection and exposure systems for their in vitro and in vivo assessment. The focus is on the specificities of the product that constitute challenges and require development of ad hoc assessment frameworks, equipment, and methods. In so doing, this review aims to support further studies, objective evaluation, comparison, and verification of existing evidence, and, ultimately, formulation of standardized methods for testing EVPs.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sonya Middleton ◽  
Sabine Steinbach ◽  
Michael Coad ◽  
Kevina McGill ◽  
Colm Brady ◽  
...  

AbstractTuberculin Purified Protein Derivatives (PPDs) exhibit multiple limitations: they are crude extracts from mycobacterial cultures with largely unknown active components; their production depends on culture of mycobacteria requiring expensive BCL3 production facilities; and their potency depends on the technically demanding guinea pig assay. To overcome these limitations, we developed a molecularly defined tuberculin (MDT) by adding further antigens to our prototype reagent composed of ESAT-6, CFP-10 and Rv3615c (DIVA skin test, DST). In vitro screening using PBMC from infected and uninfected cattle shortlisted four antigens from a literature-based list of 18 to formulate the MDT. These four antigens plus the previously identified Rv3020c protein, produced as recombinant proteins or overlapping synthetic peptides, were formulated together with the three DST antigens into the MDT to test cattle experimentally and naturally infected with M. bovis, uninfected cattle and MAP vaccinated calves. We demonstrated significant increases in MDT-induced skin responses compared to DST in infected animals, whilst maintaining high specificity in unvaccinated or MAP vaccinated calves. Further, MDT can also be applied in in vitro blood-based interferon-gamma release assays. Thus, MDT promises to be a robust diagnostic skin and blood test reagent overcoming some of the limitations of PPDs and warrants full validation.


2020 ◽  
Vol 22 (1) ◽  
pp. 206
Author(s):  
Olga Azevedo ◽  
Miguel Fernandes Gago ◽  
Gabriel Miltenberger-Miltenyi ◽  
Nuno Sousa ◽  
Damião Cunha

Fabry disease (FD) is a lysosomal storage disorder caused by mutations of the GLA gene that lead to a deficiency of the enzymatic activity of α-galactosidase A. Available therapies for FD include enzyme replacement therapy (ERT) (agalsidase alfa and agalsidase beta) and the chaperone migalastat. Despite the large body of literature published about ERT over the years, many issues remain unresolved, such as the optimal dose, the best timing to start therapy, and the clinical impact of anti-drug antibodies. Migalastat was recently approved for FD patients with amenable GLA mutations; however, recent studies have raised concerns that “in vitro” amenability may not always reflect “in vivo” amenability, and some findings on real-life studies have contrasted with the results of the pivotal clinical trials. Moreover, both FD specific therapies present limitations, and the attempt to correct the enzymatic deficiency, either by enzyme exogenous administration or enzyme stabilization with a chaperone, has not shown to be able to fully revert FD pathology and clinical manifestations. Therefore, several new therapies are under research, including new forms of ERT, substrate reduction therapy, mRNA therapy, and gene therapy. In this review, we provide an overview of the state-of-the-art on the currently approved and emerging new therapies for adult patients with FD.


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