• Biotechnology and Bioprocess Engineering:BBE
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• v.4 no.1
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• pp.66-71
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• 1999

One of the practical limitations with the use of liposomes for delivery of the pharmaceutical substances such antigens is that liposomes are relatively unstable in storage. In order to extend the stability of liposome in storage without affecting their functional activity, solution-type liposomes were dehydrated to form a structurally intact dry liposomes. Comparative immunological evaluation was carried out for both dry and solution-type liposomes containing gag-V3 chimera, consequently it was found that dry liposomes elicited both humoral and cellular response as efficiently as solution-type liposemes did against the same gag-V3 antigen. Especially, long-term stability of the liposomes was remarkably enhanced by the dehydration made to loposomes without a significant change in its ability to elicit immune response in vivo. These results indicate that dry pH-sensitive liposome may become an effective delivery and adjuvant system for general vaccine development.

• Biomolecules & Therapeutics
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• v.20 no.3
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• pp.320-325
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• 2012

Rotavirus and hepatitis A virus (HAV) spread by the fecal-oral route and infections are important in public health, especially in developing countries. Here, two antigenic epitopes of the HAV polyprotein, domain 2 (D2) and domain 3 (D3), were recombined with rotavirus VP7, generating D2/VP7 and D3/VP7, cloned in a baculovirus expression system, and expressed in Spodoptera frugiperda 9 (Sf9) insect cells. All were highly expressed, with peak expression 2 days post-infection. Western blotting and ELISA revealed that two chimeric proteins were antigenic, but only D2/VP7 was immunogenic and elicited neutralizing antibody responses against rotavirus and HAV by neutralization assay, implicating D2/VP7 as a multivalent subunit-vaccine Candidate for preventing both rotavirus and HAV infections.

• Childhood Kidney Diseases
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• v.22 no.1
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• pp.1-6
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• 2018

Rituximab (RTX) is a chimeric monoclonal antibody that inhibits CD20-mediated B-cell proliferation and differentiation. Several studies have examined its use in intractable nephrotic syndrome (NS) with some positive results. However, those studies examined such effects for a short-term period of 1 year, and some patients continued to relapse after a lapse in RTX treatment. Our use of RTX as a maintenance therapy (RTX injection when the CD19 cell count exceeded $100-200/{\mu}L$ before relapse) showed some noticeable efficacy. We used RTX in 19 patients with steroid-dependent NS (SDNS). In 12 patients treated with RTX maintenance therapy, only one relapse occurred. The mean treatment period was $23.4{\pm}12.7months$, and the mean number of RTX administrations was $3.9{\pm}1.6$. The relapse rates were decreased (from 2.68/year to 0.04/year), and the drug-free period also increased (from 22.5 days/year to 357.1 days/year) during maintenance therapy. The other seven patients were treated with one cycle of RTX or additional cycles in case of relapse (non-maintenance therapy). Relapse rates were significantly decreased after RTX treatment (from 1.76/year to 0.96/year, P=0.017). The relapse-free period was $15.55{\pm}7.38$ (range, 5.3-30.7) months. No severe side effects of RTX were found except for a hypersensitivity reaction such as fever and chills during its infusion. In conclusion, RTX is considered an effective and safe option to reduce the relapse rate by a single- or maintenance-interval therapy in SDNS.

• Biomolecules & Therapeutics
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• v.5 no.1
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• pp.53-58
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• 1997

$[Lys^7$]dermorphin, abbreviated K7DA, which has structural features similar to a metabolically stable $\mu$-opioid peptide agonist $[D-Arg^2, Lys^4$]dermorphin analogue (DALDA), but is intrinsically more potent with respect to binding to the $\mu$-opioid peptide receptor. The present studies report on attempts to enhance brain uptake of systemically administered K7DA by conjugation to a complex of streptavidin (SA) and the OX26 murine monoclonal antibody to the rat transferrin receptor, which undergoes receptor-mediated transcytosis through the blood-brain barrier (BBB). SA-OX26 conjugate mediates BBB transport of biotinylated therapeutics. The K7DA is monobiotinylated at the $\varepsilon$-amino group of the $[Lys^7$] residue with cleavable linker using NHS-SS-biotin. The brain uptake of $^{125}I$ labeled biotinylated K7DA ($^{125}I$-bio-SSa-K7DA) was very small and rapidly metabolized after intravenous injection. The brain uptake, expressed as percent of injected dose delivered per gram of brain, of the $^{125}I$-bio-55-K7DA bound to the SA-OX26 conjugate $^{125}I$-bio-SS-K7DA/SA-OX26) was 0.14$\pm$0.01, a level that is 2-fold greater than the brain uptake of morphine. The cleavability of the disulfide linker in vivo in rat plasma and brain was assessed with gel filtration HPLC and intravenous injection of labeled opioid chimeric peptides. The disulfide linker is stable in plasma in vivo but is cleaved in rat brain in vivo. In conclusion, these studies show that delivery of these potential opioid peptides to the brain may be improved by coupling them to vector-mediated BBB drug delivery system.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2001.11a
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• pp.40-46
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• 2001

The use of pluripotent stem cells has tremendous advantages for various purposes but these cell lines with proven germ-line transmission have been completely established only in the mouse. Embryonic germ (EG) cell lines are also pluripotent and undifferentiated stem cells established from primordial germ cells (PGCs). This study was conducted to establish and characterize the chicken EG cells derived from gonadal primordial germ cells. We isolated gonadal PGCs from 5.5-day-old (stage 28) White leghorn (WL) embryos and established chicken EG cells lines with EG culture medium supplemented with human stem cell factor (hSCF), murine leukemia inhibitory factor (mLIF), bovine basic fibroblast growth factor (bFGF), human interleukin-11 (hIL-11), and human insulin-like growth factor-I (hIGF-I). These cells grew continuously for 4 months (10 passages) on a feeder layer of mitotically active chicken embryonic fibroblasts. These cells were characterized by screening with the Periodic acid-Shiff＇s reaction, anti-SSEA-1 antibody, and a proliferation assay after several passages. As the results, the chicken EG cells maintained characteristics of undifferentiated stem cells as well as that of gonadal PGCs. When cultured in suspension, the chicken EG cells successfully formed an embryoid body and differentiated into a variety of cell types when re-seeded onto culture dish. The chicken EG cells were injected into blastodermal layer at stage X and dorsal aorta of recipient embryo at stage 14 (incubation of 53hrs) and produced chimeric chickens with various differentiated tissues derived from the EG cells. The germline chimeras were also successfully induced by using EG cells. Thus, Chicken EG cells will be useful for the production of transgenic chickena and for studies of germ cell differentiation and genomic imprinting.

• Childhood Kidney Diseases
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• v.16 no.2
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• pp.138-141
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• 2012

Rituximab, a chimeric anti-CD20 IgG1 monoclonal antibody, has been used as a rescue therapy for steroid-dependent or refractory nephrotic syndrome. However, the adverse effects of rituximab are yet to be investigated. We report a case of a 9-year-old boy with steroid-dependent nephrotic syndrome who developed Kikuchi-Fujimoto disease after several cycles of rituximab therapy. Kikuchi-Fujimoto disease is a benign, self-limited necrotizing histiocytic lymphadenitis of unknown etiology. In the present case, Kikuchi-Fujimoto disease developed when the peripheral blood B-cell count of the patient was at nadir, and the lesion regressed slowly but spontaneously after recovery of the B-cell count. To our knowledge, although the pathologic diagnosis of Kikuchi-Fujimoto disease was unavailable, this is the first report of Kikuchi-Fujimoto disease with clinical diagnosis as a possible adverse effect of rituximab.

• Animal cells and systems
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• v.1 no.1
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• pp.157-164
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• 1997

Ly-6E.1 antigen was proposed as a regulatory molecule of T lymphocyte activation, a hematopoietic stem cell marker, a memory cell marker, and an adhesion molecule. Though there were several reports suggesting the presence of Ly-6 ligand, the characterization of the ligand was not yet performed, As an attempt to screen the expression of Ly-6E.1 ligand, we prepared a probe for detecting Ly-6E.1 ligand by producing a fusion protein between Ly-6E.1 and $hlgC_{r1}$, A mammalian cell expression vector with Ly-6E.$1/hlgC_{r1}$ chimeric cDNA was transfected in SP2/0-Ag14 myeloma cells, and stable transfectants were selected. The fusion protein was produced as a dimer and maintained the epitopes for monoclonal antibodies specific for Ly-6E.1 and for anti-human lgG antibody. The purified fusion protein through Gammabind G column was used for FACS analyses for the expression of Ly-6E.1 ligand. The fusion protein interacted with several cell lines originating from B cells, T cells, or monocytes. The fusion Protein also strongly stained bone marrow, lymph node, and spleen cells, but thymic cells weakly, if any. The staining was more obvious in C57BL/6 $(Ly-6^b)$ than Balb/c $(Ly-6^a)$ mice. These results suggest that the interaction of Ly-6E.1 with Ly-6E.1 ligand may function both in the stem cell environment and in the activation of mature lymphocytes. The fusion protein may be a valuable tool in characterization of biochemical properties of the Ly-6E.1 ligand and, further, in isolating its cDNA.