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Studies investigating physiological deviations from normality in newborn calves derived from in vitro fertilization procedures remain important for the understanding of factors that reduce calf survival after birth. The aim of this study was to investigate parameters affecting health and welfare of newborn Flemish calves derived from in vitro embryo production (IVP) in the first hours of life in comparison to in vivo-derived calves. Physical traits of newborn calves and fetal membranes (FM) were recorded soon after birth. Newborn venous blood samples were collected at several time points within the first 24 h of life for analyses of energy substrates, electrolytes, blood gases, acid-base balance, blood chemistry, and haematology. A liver biopsy was taken within the first hour after birth for analysis of gene expression of key enzymes of the fructolytic and glycolytic pathways. Newborn IVP calves were heavier and larger at birth, which was associated with heavier FM. At several time points during the first 24 h of life, IVP-derived calves had altered rectal temperature, blood gases, electrolyte concentrations, blood parameters for liver, kidney and muscle function, and acid-base balance, plasma lipid metabolism, and hemogram parameters. The relative mRNA abundances for triokinase and lactate dehydrogenase-B were greater in IVP calves. In summary, IVP-derived newborn calves were at higher risk of clinical problems after birth, which was markedly greater in heavier and larger calves. Such animals take longer to adapt to extrauterine life and should receive a special attention during the immediate neonatal period.

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The genotyping of genetically-modified cells is a crucial step in studies of transgenics and genomic editing with systems such as CRISPR/Cas. The detection of genome editing events can be directly related to the genotyping methodology used, which is influenced by its costs, since many experiments require the analysis of a large number of samples. The aim of this study was to compare the performance of direct lysis methods of genomic DNA (gDNA) extraction for the detection of knockins and knockouts in primary goat cells. Initially, three gDNA extraction protocols (protocol A, heat denaturation/freeze-thaw in water; protocol B, heat denaturation/proteinase K; and protocol C, CellsDirect Kit) were tested using different quantities (1,000, 5,000 and 10,000 cells) and types of goat primary cells (fibroblasts and goat mammary epithelial cells-GMECs) for subsequent validation by PCR amplification of small (GAPDH) and large amplicons (hLF transgene). All protocols were successful in the detection of the small amplicon; however, in GMECs, only protocol B resulted efficient amplification (protocol A-0%, protocol B-93%, protocol C-13.33%, P <0.05). In a proof-of-principle experiment, the TP53 gene was knocked out in GMECs by CRISPR/Cas9-mediated deletion while constructs containing the anti-VEGF monoclonal antibody (pBC-anti-VEGF) and bacterial L-Asparaginase (pBC-ASNase) transgenes were knocked-in separately in fibroblasts. Detection of successful editing was performed using protocol B and PCR. The integration rates of the pBC-ASNase and pBC-anti-VEGF transgenes were 93.6% and 72%, respectively, as per PCR. The efficiency of biallelic editing in GMECs using CRISPR/Cas9 for the TP53 deletion was 5.4%. Our results suggest that protocol B (heat denaturation/proteinase K) can be used as an inexpensive and quick methodology for detecting genetic modifications in different types of primary goat cells, with efficiency rates consistent with values previously described in the literature when using extraction kits or more complex proteinase K formulations.

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OBJECTIVE: L-Asparaginase (ASNase) is an enzyme used in the treatment of acute lymphoblastic leukemia (ALL). As the therapeutic ASNases has bacterial origin, severe side effects are associated with its use, among them hypersensitivity and inactivation of the enzyme. In this context, the objective of this work was to produce a recombinant ASNase of bacterial origin in human cells in order to determine the presence and consequences of potential post-translational modifications on the enzyme. RESULTS: Recombinant ASNase was expressed in human cells with a molecular weight of 60 kDa, larger than in Escherichia coli, which is 35 kDa. N-glycosylation analysis demonstrated that the increased molecular weight resulted from the addition of glycans to the protein by mammalian cells. The glycosylated ASNase presented in vitro activity at physiological pH and temperature. Given that glycosylation can act to reduce antigenicity by masking protein epitopes, our data may contribute to the development of an alternative ASNase in the treatment of ALL in patients who demonstrate side effects to currently marketed enzymes.

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Gaucher disease (GD) is an orphan disease characterized by the lack or incapacity of glucocerebrosidase (hGCase) to properly process glucosylceramide, resulting in its accumulation in vital structures of the human body. Enzyme replacement therapy supplies hGCase to GD patients with a high-cost recombinant enzyme produced in vitro in mammalian or plant cell culture. In this study, we produced hGCase through the direct injection of recombinant adenovirus in the mammary gland of a non-transgenic goat. The enzyme was secreted in the milk during six days at a level up to 111.1 ± 8.1 mg/L, as identified by mass spectrometry, showing high in vitro activity. The milk-produced hGCase presented a mass correspondent to the intermediary high-mannose glycosylated protein, which could facilitate its delivery to macrophages through the macrophage mannose receptor. Further studies are underway to determine the in vivo delivery capacity of milk-hGCase, but results from this study paves the way toward the generation of transgenic goats constitutively expressing hGCase in the milk.

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Background: The production of transgenic animals has been envisioned as a viable strategy to improve food quality, animal yield, and for the production of bioproducts that can be used for the benefit of the human and animal population. Transgenic animals have been used to improve production traits, to add value to animal products, to minimize the impact on the environment, to promote disease resistance, and most notably, to produce recombinant proteins in natural fluids, such as milk, that can be collected, purified and used as biomedical products (biopharming). This review aims to discuss past and recent technological advances in animal transgenesis, and the perspective for biopharming in Brazil.Review: Since the production of recombinant human insulin from Escherichia coli in the 1970s, continuous development of new platforms has allowed a significant expansion in the biopharmaceutical market. The animal platform has been shown to be highly competitive by adding value as low cost implementation, production and scale up, as well as high productivity of synthesized proteins. The expression of recombinant proteins in milk represents the most developed system for production of biopharmaceutical drugs in animals, with two approved biopharmaceuticals for human use: Atryn®, a recombinant antithrombin produced in the milk of goats, approved in 2006 by European Medicines Agency (EMA) and in 2009 by US Food and Drug Administration (FDA), and more recently, Ruconest®, a recombinant human C1 esterase inhibitor protein (C1INH) produced in the milk of rabbits, first approved by EMA in 2012, followed by the FDA approval in 2014. Transgenic animals have been produced by many strategies that have gradually evolved over the decades, including the use of embryo microinjection, viral vectors and transposable elements, sperm-mediated gene transfer, and cloning by somatic cell nuclear transfer (SCNT).[...]

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Background: The production of transgenic animals has been envisioned as a viable strategy to improve food quality, animal yield, and for the production of bioproducts that can be used for the benefit of the human and animal population. Transgenic animals have been used to improve production traits, to add value to animal products, to minimize the impact on the environment, to promote disease resistance, and most notably, to produce recombinant proteins in natural fluids, such as milk, that can be collected, purified and used as biomedical products (biopharming). This review aims to discuss past and recent technological advances in animal transgenesis, and the perspective for biopharming in Brazil.Review: Since the production of recombinant human insulin from Escherichia coli in the 1970s, continuous development of new platforms has allowed a significant expansion in the biopharmaceutical market. The animal platform has been shown to be highly competitive by adding value as low cost implementation, production and scale up, as well as high productivity of synthesized proteins. The expression of recombinant proteins in milk represents the most developed system for production of biopharmaceutical drugs in animals, with two approved biopharmaceuticals for human use: Atryn®, a recombinant antithrombin produced in the milk of goats, approved in 2006 by European Medicines Agency (EMA) and in 2009 by US Food and Drug Administration (FDA), and more recently, Ruconest®, a recombinant human C1 esterase inhibitor protein (C1INH) produced in the milk of rabbits, first approved by EMA in 2012, followed by the FDA approval in 2014. Transgenic animals have been produced by many strategies that have gradually evolved over the decades, including the use of embryo microinjection, viral vectors and transposable elements, sperm-mediated gene transfer, and cloning by somatic cell nuclear transfer (SCNT).[...](AU)

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A clonagem animal por transferência nuclear de célula somática (TNCS) apresenta inúmeras aplicações científicas e comerciais, incluindo a produção de animais transgênicos, a preservação de animais de genética desejável, rara ou em extinção, ou mesmo a aplicação para o estudo de aspectos básicos em biologia molecular, celular e do desenvolvimento. Não obstante, a clonagem por TNCS ainda é ineficiente, com menos de 5% dos embriões clones produzidos resultando em animais nascidos vivos. O sucesso na clonagem exige o exímio domínio técnico e científico de várias disciplinas e áreas de conhecimento, havendo pelo menos cinco etapas críticas no processo associadas a falhas de desenvolvimento, desde a produção in vitro dos embriões até o nascimento de um animal viável. A identificação de fatores associados às falhas em cada etapa, em especial aqueles relacionados ao oócito receptor (citoplasto), à célula doadora (carioplasto) e aos procedimentos técnicos per se de produção de embriões clones, além da observação cuidadosa dos sinais de anormalidades subsequentes à transferência dos embriões para fêmeas receptoras, é essencial para a optimização de todos os procedimentos para a obtenção, em seu final, de um animal clonado viável e que sobreviva até a vida adulta. Esta revisão visa descrever alguns eventos técnicos e biológicos associados ao sucesso e/ou insucesso da clonagem animal.(AU)

Animal cloning by somatic cell nuclear transfer (SCNT) has numerous scientific and commercial applications, including the production of transgenic animals, preservation of animals from desirable or rare gene pools, and animals in risk of extinction, or even for the study of basic aspects in molecular, cell and developmental biology. Nevertheless, cloning by SCNT is still inefficient, with less than 5% of cloned embryos resulting in liveborn animals. The cloning success depends on a proficient technical and scientific know-how of a number of disciplines and areas of knowledge, with at least five critical steps in the process associated with developmental failures, from the in vitro production of cloned embryos through the birth of a viable animal. The identification of factors associated with failures in each step, in special to those related to the recipient oocyte (cytoplast), to the nucleus donor cell (karyoplast), and to the technical procedures for the production of cloned embryos per se, along with the careful observation of signs of abnormalities following the transfer of embryos to recipient females, is essential for the optimization of procedures that, ultimately, may result in a cloned animal that survives to adulthood. This review aims to discuss some technical and biological events associated with success and/or failure in animal cloning.(AU)

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Materials, Methods & Results: In vitro-matured bovine cumulus-oocyte complexes (COC) were manually bisected after cumulus and zona pellucida removal; then, two enucleated hemi-oocytes were paired and fused with either a wild type (WT) or a GFP-expressing (GFP) fetal skin cell at the 11th and 19th passages, respectively. Following chemical activation, reconstructed cloned embryos and zona-free parthenote embryos were in vitro-cultured in microwells, for 7 days, either individually (1 x 100%) or after the aggregation of two structures (2 x 100%) per microwell, as follows: (G1) one WT cloned embryo; (G2) two aggregated WT embryos; (G3) one GFP cloned embryo; (G4) two aggregated GFP embryos; (G5) aggregation of a WT embryo and a GFP embryo; (G6) one parthenote embryo; or (G7) two aggregated parthenote embryos. Fusion (clones), cleavage (Day 2), and blastocyst (Day 7) rates, and embryonic cell allocation were compared by the 2 or Fisher tests. Total cell number (TCN) in blastocysts was analyzed by the Student´s test (P 0.05). Fusion and cleavage rates, and cell allocation were similar between groups. On a per WOW basis, development to the blastocyst stage was similar between groups, except for lower rates of development seen in G3. However, when based on number of embryos per group (one or two), blastocyst development was higher in G1 than all other groups, which were simi

Background: The in vitro production (IVP) of embryos by in vitro fertilization or cloning procedures has been known to cause epigenetic changes in the conceptus that in turn are associated with abnormalities in pre- and postnatal development. Handmade cloning (HMC) procedures and the culture of zona-free embryos in individual microwells provide excellent tools for studies in developmental biology, since embryo development and cell allocation patterns can be evaluated under a wide range of embryo reconstruction arrangements and in in vitro embryo culture conditions. As disturbances in embryonic cell allocation after in vitro embryo manipulations and unusual in vivo conditions during the fi rst third of pregnancy appear to be associated with large offspring, embryo aggregation procedures may allow a compensation for epigenetic defects between aggregated embryos or even may infl uence more favorable cell allocation in embryonic lineages, favoring subsequent development. Thus, the aim of this study was to evaluate in vitro embryo developmental potential and the pattern of cell allocation in blastocysts developed after the aggregation of handmade cloned embryos produced using syngeneic wild type and/or transgenic somatic cells.Materials, Methods & Results: In vitro-matured bovine cumulus-oocyte complexes (COC) were manually bisected after cumulus and zona pellucida removal; then

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Background: The in vitro production (IVP) of embryos by in vitro fertilization or cloning procedures has been known to cause epigenetic changes in the conceptus that in turn are associated with abnormalities in pre-and postnatal development. Handmade cloning (HMC) procedures and the culture of zona-free embryos in individual microwells provide excellent tools for studies in developmental biology, since embryo development and cell allocation patterns can be evaluated under a wide range of embryo reconstruction arrangements and in in vitro embryo culture conditions. As disturbances in embryonic cell allocation after in vitro embryo manipulations and unusual in vivo conditions during the first third of pregnancy appear to be associated with large offspring, embryo aggregation procedures may allow a compensation for epigenetic defects between aggregated embryos or even may influence more favorable cell allocation in embryonic lineages, favoring subsequent development. Thus, the aim of this study was to evaluate in vitro embryo developmental potential and the pattern of cell allocation in blastocysts developed after the aggregation of handmade cloned embryos produced using syngeneic wild type and/or transgenic somatic cells. Materials, Methods & Results: In vitro-matured bovine cumulus-oocyte complexes (COC) were manually bisected after cumulus and zona pellucida removal; then, two enucleated hemi-oocytes were paired and fused with either a wild type (WT) or a GFP-expressing (GFP) fetal skin cell at the 11th and 19th passages, respectively. Following chemical activation, reconstructed cloned embryos and zona-free parthenote embryos were in vitro-cultured in microwells, for 7 days, either individually (1 x 100%) or after the aggregation of two structures (2 x 100%) per microwell, as follows: (G1) one WT cloned embryo; (G2) two aggregated WT embryos; (G3) one GFP cloned embryo; (G4) two aggregated GFP embryos; (G5) aggregation of a WT embryo and a GFP embryo; (G6) one parthenote embryo; or (G7) two aggregated parthenote embryos. Fusion (clones), cleavage (Day 2), and blastocyst (Day 7) rates, and embryonic cell allocation were compared by the x² or Fisher tests. Total cell number (TCN) in blastocysts was analyzed by the Student's test (P < 0.05). Fusion and cleavage rates, and cell allocation were similar between groups. On a per WOW basis, development to the blastocyst stage was similar between groups, except for lower rates of development seen in G3. However, when based on number of embryos per group (one or two), blastocyst development was higher in G1 than all other groups, which were similar between one another. Cloned GFP embryos had lower in vitro development to the blastocyst stage than WT embryos, which had more TCN than parthenote or aggregated chimeric WT/GFP embryos. Aggregated GFP embryos had fewer cells than the other embryo groups. Discussion: The in vitro development of GFP cloned embryos was lower than WT embryos, with no effects on cell allocation in resulting blastocysts. Differences in blastocyst rate between groups were likely due to lower GFP-expressing cell viability, as GFP donor cells were at high population cell doublings when used for cloning. On a per embryo basis, embryo aggregation on Day 1 resulted in blastocyst development similar to non-aggregated embryos on Day 7, with no differences in cell proportion between groups. The use of GFP-expressing cells was proven a promising strategy for the study of cell allocation during embryo development, which may assist in the elucidation of mechanisms of abnormalities after in vitro embryo manipulations, leading to the development of improved protocols for the in vitro production (IVP) of bovine embryos.

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A clonagem animal por transferência nuclear de célula somática (TNCS) apresenta inúmeras aplicações científicas e comerciais, incluindo a produção de animais transgênicos, a preservação de animais de genética desejável, rara ou em extinção, ou mesmo a aplicação para o estudo de aspectos básicos em biologia molecular, celular e do desenvolvimento. Não obstante, a clonagem por TNCS ainda é ineficiente, com menos de 5% dos embriões clones produzidos resultando em animais nascidos vivos. O sucesso na clonagem exige o exímio domínio técnico e científico de várias disciplinas e áreas de conhecimento, havendo pelo menos cinco etapas críticas no processo associadas a falhas de desenvolvimento, desde a produção in vitro dos embriões até o nascimento de um animal viável. A identificação de fatores associados às falhas em cada etapa, em especial aqueles relacionados ao oócito receptor (citoplasto), à célula doadora (carioplasto) e aos procedimentos técnicos per se de produção de embriões clones, além da observação cuidadosa dos sinais de anormalidades subsequentes à transferência dos embriões para fêmeas receptoras, é essencial para a optimização de todos os procedimentos para a obtenção, em seu final, de um animal clonado viável e que sobreviva até a vida adulta. Esta revisão visa descrever alguns eventos técnicos e biológicos associados ao sucesso e/ou insucesso da clonagem animal.

Animal cloning by somatic cell nuclear transfer (SCNT) has numerous scientific and commercial applications, including the production of transgenic animals, preservation of animals from desirable or rare gene pools, and animals in risk of extinction, or even for the study of basic aspects in molecular, cell and developmental biology. Nevertheless, cloning by SCNT is still inefficient, with less than 5% of cloned embryos resulting in liveborn animals. The cloning success depends on a proficient technical and scientific know-how of a number of disciplines and areas of knowledge, with at least five critical steps in the process associated with developmental failures, from the in vitro production of cloned embryos through the birth of a viable animal. The identification of factors associated with failures in each step, in special to those related to the recipient oocyte (cytoplast), to the nucleus donor cell (karyoplast), and to the technical procedures for the production of cloned embryos per se, along with the careful observation of signs of abnormalities following the transfer of embryos to recipient females, is essential for the optimization of procedures that, ultimately, may result in a cloned animal that survives to adulthood. This review aims to discuss some technical and biological events associated with success and/or failure in animal cloning.

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