• Korean Journal of Animal Reproduction
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• v.25 no.1
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• pp.85-90
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• 2001

To study the signaling effect of growth hormone (GH) in vivo on animal physiology, transgenic mice containing GH Receptor (GHR) gene fused to metallothionein promoter were produced by DNA microinjection into one-cell stage embryos. Three founder mice were produced with transgenic mice with approximately 4~6 copies of GHR genes and transgene was transmitted into the progeny. The founder mice were mated with normal mice to produce F$_1$ mice, and intergation and transmission of transgene were checked by polymerase chain reaction and Southern blot methods. Transmission rate of GHR transgenic mice were 20~50% in F$_1$ generation and 50% in F$_2$ generation which means that some founder mice were mosaic and transgene in F$_1$ mice was transmitted to F$_2$ progeny with Mendelian ratio. Death rate of GHR transgenic mice after birth was about 10~30% in F$_1$ and F$_2$ progenies indicating that GHR gene may affect death of transgnenic progeny.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.6
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• pp.743-749
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• 2004

The gene encoding human serum albumin (HSA) was cloned from human liver cDNA library by PCR. The HSA cDNA in size of 2,176 bp, including 1,830 bp of open reading frame, was cloned into the plasmid carried with the 5'flanking sequence of goat $\beta$-casein gene (-4,044 to +2,025 bp) to get a tissue specific expression vector in mammary gland named pGB562/HSA (12.5 kb). A 9.6 kb DNA fragment in which the sequence is in order of goat $\beta$-casein gene regulatory sequence, HSA cDNA and SV40 polyadenylation signals was isolated from the pGB562/HSA by SacI and DraIII cutting, and used to microinject into the pronuclei of mouse fertilized eggs to produce transgenic mice. Three transgenic mice (2 female and 1 male) were identified by PCR and dot Southern blot analysis. The copy numbers of integrated transgene were more than 10 copies in line #21 and #26 as well as over 50 copies in line #31 of transgenic mice. HSA protein collected from the milk of lactating transgenic mice was confirmed by immuno-detection of Western and slot blot. The concentrations of HSA in the milk were from 0.05 to 0.4 mg/ml. An obvious antigen and antibody conjugate could be observed in immunohistochemical stain of mammary gland tissue from lactating day 11 of HSA transgenic mice. The transmission of transgene and its expression was recognized according to the results of RT-PCR and sequences analyses of their progeny.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.46-46
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• 2003

Interleukin-10 (IL-10) is a homodimeric protein with a wide spectrum of anti-inflammatory and immune activities. It inhibits cytokine production and expression of immune surface molecules in various cell types. The transgenic mice carrying the human IL-10 gene in conjunction with the bovine $\beta$-casein promoter produced the human IL-10 in milk during lactation. Transgenic mice were generated using a standard method as described previously. To screen transgenic mice, PCR was carried out using chromosomal DNA extracted from tail or toe tissues with a primer set. In this study, stability of germ line transmission and expression of IL-10 gene integrated into host chromosome were monitored up to generation F15 of a transgenic line. When female mouse of generation F9 was crossbred with normal male, generation F9 to F15 mice showed similar transmission rates (66.0$\pm$20.13%, 61.5$\pm$16.66%, 41.1$\pm$8.40%, 40.7$\pm$20.34%, 61.3$\pm$10.75%, 49.2$\pm$18.82%, and 43.8$\pm$25.91%, respectively), implying that the IL-10 gene can be transmitted stably up to long term generation in the transgenic mice. For ELISA analysis, IL-10 expression levels were determined with an hIL-10 ELISA and a mIL-10 ELISA kit in accordance with the supplier's protocol. Expression levels of human IL-10 from milk of generation F9 to F13 mice were 3.6$\pm$1.20 mg/ml, 4.2$\pm$0.93 mg/ml, 5.7$\pm$1.46 mg/ml, 6.3$\pm$3.46 mg/ml, and 6.8$\pm$4.52 mg/ml, respectively. These expression levels are higher than in generation F1 (1.6 mg/ml) mice. We concluded that transgenic mice faithfully passed the transgene on their progeny and successively secreted target proteins into their milk through several generations, although there was a little fluctuation in the transmission frequency and expression level between the generations.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.427-438
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• 2020

Middle East respiratory syndrome coronavirus (MERS-CoV) infects the lower respiratory airway of humans, leading to severe acute respiratory failure. Unlike human dipeptidyl peptidase 4 (hDPP4), a receptor for MERS-CoV, mouse DPP4 (mDPP4) failed to support MERS-CoV infection. Consequently, diverse transgenic mouse models expressing hDPP4 have been developed using diverse methods, although some models show no mortality and/or only transient and mild-to-moderate clinical signs following MERS-CoV infection. Additionally, overexpressed hDPP4 is associated with neurological complications and breeding difficulties in some transgenic mice, resulting in impeding further studies. Here, we generated stable hDPP4-transgenic mice that were sufficiently susceptible to MERS-CoV infection. The transgenic mice showed weight loss, decreased pulmonary function, and increased mortality with minimal perturbation of overexpressed hDPP4 after MERS-CoV infection. In addition, we observed histopathological signs indicative of progressive pulmonary fibrosis, including thickened alveolar septa, infiltration of inflammatory monocytes, and macrophage polarization as well as elevated expression of profibrotic molecules and acute inflammatory response in the lung of MERS-CoV-infected hDPP4-transgenic mice. Collectively, we suggest that this hDPP4-transgenic mouse is useful in understanding the pathogenesis of MERS-CoV infection and for antiviral research and vaccine development against the virus.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.17-17
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• 2003

The milk of transgenic animals may provide an attractive vehicle for large-scale production of hEPO. Since glycosylation is cell type specific, recombinant human EPO (rhEPO) produced in different host cells contain different patterns of oligosaccharides, which could affect the biological functions. However, there have been no reports on the characteristics of rhEPO derived from milk of transgenic animals. To address this objective, several transgenic mice by using pWAPhEPO and/or pBC1hEPO expression vector were produced. However, 2 lines of pWAPhEPO founder female mouse died during late gestational day (day 18) before offspring could be obtained. They showed a severe splenomegaly, Unlike those of pWAPhEPO, mammary gland epithelial cells from biopsies of lactating pBC1hEPO transgenic mice had marked immunoreactivity to EPO and any activity was not detected in other tissues. The expression level of rhEPO is about 0.7% of mammary gland cellular total soluble proteins and an amount of 300~500 mg/L rhEPO is secreted into milk. Furthermore, the pBC1hEPO transgenic mice transmitted this character to their progeny in mendelian manner. In order to determine the extent of glycosylation variation, N-linked oligosaccharide structures present in the milk-derived rhEPO were characterized. Most of milk-derived rhEPO is fully glycosylated. the biological activity of milk-derived rhEPO was comparable to that of purified CHO-derived rhEPO, and milk-derived rhEPO showed relatively stable after freezing and thawing. Taken together, the results illustrate the potential of transgenic animals in the large-scale production of biopharmaceuticals.

• Korean Journal of Animal Reproduction
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• v.22 no.2
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• pp.145-152
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• 1998

Many trials have been made to produce transgenic animals using sperm cells as a vector transferring foreign DNA into eggs, but reliable results are yet to be obtained (Brinster et al., 1989; Lavitrano et al., 1989; Bachiller et al., 1991; Sato et al., 1994). Recently, one of author(SO) demonstrated that mouse blastocysts derived from eggs fertilized by spermatozoa of male mice single injected with liposome-DNA complexes within the testis expressed thegene (Ogawa et al., 1995.) Here we report that a single injection of liposome-encapsulated DNAs into the testis of either male rats or mice resulted in successfully gene transfer to the postpartum progeny. The expression of mRNA derived from transgenes was also demonstrated in transgenic animals thus obtained. Further, the transmission of the exogenous gene to the descedants was confirmed in one line of transgenic rat up to F4 generation, indicating that the gene was stably incorporated into the germ line. Thus, direct single injection of foreign DNA into the testis provides a novel and convenient means to generate transgenic animals.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.59-59
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• 2001

Interleukin-10 (IL-10) is known as a regulator of inflammation and pathogenesis in mammalian organs, but its precise role is little known in the mammary gland. Our initial experiment showed that IL-10 expression levels in mice decreased at the lactation stage otherwise increased at the involution stage. To reveal the effects of IL-10 on the involution of mammary gland, expression profiles of the apoptosis-related genes were examined in transgenic mice expressing human IL-10 as well as in knock-out mice (IL-10-/-). Mild inflammatory legions by lymphocytes were observed in the mammary glands of transgenic lines at the lactation stage. The expression of TRAIL (Tumor necrosis factor-Related Apoptosis-Inducing Ligand) among the apoptosis-related genes was highly elevated in the transgenic mice while others were not significantly changed. Furthermore, TRAIL was down regulated by four fold in the IL-10-/- mice at the involution stage. The expression of DR4 was elevated at the involution stage of normal mice. DR4 was detected in the milk of transgenic mice but absent in that of normal mice. Our results proposed that the elevated IL-10 at the involution stage recruit lymphocytes and induce TRAIL and DR4 genes, therefore, lead to enter involution stage of mammary glands.

• Korean Journal of Biological Psychiatry
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• v.6 no.2
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• pp.149-152
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• 1999

Transgenic mice models of Alzheimer's disease were produced by overexpressing APP(amyloid precursor protein) mutant and presenilin mutant genes using the promotors that induced neuronal expression. The neuropathologies, electrophysiological changes and behavioral changes that were demonstrated in these transgenic mice models were amyloid changes, gliotic changes, A-beta increases, deficit in LTP(long-term potentiation) and behavioral changes. Some or all of the above changes were found in each transgenic mice model. These models generally showed amyloid neuropathology but they usually lacked the neurofibrillary tangles. So, they can be regarded as partial models of Alzheimer's disease. The development of them is undoubtedly the great progress toward future research.

• KSBB Journal
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• v.13 no.6
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• pp.718-723
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• 1998

The effect of glycyrrhizin on melanoma cells was investigated. DNA fragmentation in cultured melanoma cells was promoted by the addition of glycyrrhizin in a dose dependent manner. Administration(i.m.) of glycyrrhizin to Mel/ret transgenic mice resulted in apoptosis induction, reduction of mitochondrial transmembrane potential in melanoma cells. Decreased B220+ B cells were recovered by the treatment of glycyrrhizin in splenocytes and mesenteric lymph node cells, while Thy-1+ T cells were not influenced. Results suggested that glycyrrhizin acted as an inducer of apoptosis of melanoma cells and an immuno-potentiator via recovered B lymphocyte population in Mel/ret transgenic mice.

• Food Industry And Nutrition
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• v.4 no.3
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• pp.83-87
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• 1999

Non-insulin-dependent diabetes mellitus (NIDDM) is characterized by insulin resistance and impaired insulim secretion. The transgenic technology, in which a specific gene can be introduced or deleted to study its function, has been established. A number of transgenic mice, altered the expression of genes potentially involved in insulin action or pancreatic ${\beta}$-cell function, have recently been developed to address questions concerning NIDDM. Thransgenic mice model may help understanding the molecular basis of complex patho-physiologies of NIDDM. This review outlines the new insights obtained from the studies of transgenic mice that overxpress or show decreased expression of putative key genes involved in the regulation of insulin resistance and pancreatic ${\beta}$-cell function, therefore in the control of glucose homeostasis.