OBJECTIVETo investigate differences between hepatic and biliary lipid metabolism and secretion of genetically gallstone-susceptible (C57L) and resistant (AKR) mice and the mechanism of cholesterol gallstone formation.

METHODSThe inbred C57L and AKR mice were fed a lithogenic diet containing 15% fat, 1.25% cholesterol and 0.5% cholic acid for four weeks. Hepatic cholesterol content and secretion rates of biliary lipids, as well as phenotypes of the liver and gallbladder were determined and examined before and after the feeding of the lithogenic diet.

RESULTSBoth before and after ingestion of the lithogenic diet, hepatic secretion rates of all biliary lipids in C57L mice were markedly higher than that of AKR mice (P < 0.05, P < 0.01, respectively), whereas hepatic cholesterol contents of C57L mice were significantly lower than that of AKR mice (P < 0.05). Furthermore, after consumption of the lithogenic diet, the increase in hepatic secretion rate of biliary cholesterol in C57L mice was significantly higher than that in AKR mice (P < 0.01). Cholesterol gallstones formed in C57L mice and fatty livers developed in AKR mice.

CONCLUSIONSBiliary cholesterol hypersecretion is the key pathophysiological defect of gallstone formation, lith genes have effects on biliary cholesterol hypersecretion and susceptibility to cholesterol gallstone formation in C57L mice. Lithogenic bile is formed at the canalicular membrane and precedes the development of cholesterol gallstones. It is most likely that cholesterol and bile acid hyposecretion make the AKR strain susceptible to the development of fatty livers and resistant to gallstone formation.

Animals ; Bile ; metabolism ; Cholelithiasis ; genetics ; metabolism ; Cholesterol ; analysis ; metabolism ; Fatty Liver ; etiology ; Genetic Predisposition to Disease ; Lipid Metabolism ; Liver ; metabolism ; Male ; Mice ; Mice, Inbred AKR ; Mice, Inbred C57BL

Without serum to provide adherent factors, CHO-dhfr- cells grow in suspension when cultured in serum-free medium. Although this offers advantages in some applications, in most production systems adherent cell growth is preferable. Gene transfection, clonal selection and amplification can be easier for adherent cells; the density of immobilized cells is often higher than those in suspension culture, which results in a higher protein productivity; washout of cells by perfused medium during continuous fermentation can be avoided; for high-throughput microplate assays, adherent cells are preferred to facilitate medium changes and cell washing. It has been proved that purified vitronectin alone was able to mediate attachment and spreading of CHO cells in serum-free medium. So we constructed a tricistronic expression vector expressing Igf-1, Vitronectin and Bel-2 at the same time. The vector was transfected into CHO-dhfr- cells and one clone, namely CHO-IVB2, expressing high level of the three proteins was screened out by Western blot. The cell line showed similar apoptosis-resistant and serum-independent properties to CHO-IB, an engineered cell line constructed before. When cultured in IMEM protein-free medium without any components supplemented, CHO-IVB can grow adherently. The viable cell numbers and growth rate of CHO-IVB were much higher than CHO-IB, making CHO-IVB an apoptosis-resistant host for production of recombinant proteins which can grow adherently in protein-free medium.
Animals ; Apoptosis ; CHO Cells ; physiology ; Cell Adhesion ; Cell Line ; Cell Proliferation ; Cricetinae ; Cricetulus ; Culture Media, Serum-Free ; Flow Cytometry ; Mice ; Mice, Inbred BALB C ; Recombinant Proteins ; biosynthesis ; Vitronectin ; genetics

OBJECTIVETo further study the therapy of wasting muscle by myostatin as a new targets, the eucaryotic expression vector coupled the foreign T-helper epitope of tetanus toxin (TT) to the N terminus of myostatin was constructed, and the effects of the gene vaccine on forelimb grip were tested in immunized mice.

METHODSA DNA fragment encoding the TT epitope followed by the N terminus of mature myostatin (330bp) was synthesized. The eucaryotic expression vector of myostatin was constructed and the chinese hamster ovary (CHO) cells were infected with the recombinant plasmids pVAC-TT-Ms by liposome transfection according to routine laboratory procedure. The myostatin expression was tested by cell immunofluorescence technique in transfected CHO. The forelimbs grip were tested in immunized mice with myostatin gene vaccine.

RESULTSThe eucaryotic expression vector of myostatin coupled TT epitope was constructed successfully through the restriction analysis and sequencing. The recombinant plasmids pVAC-TT-Ms met quality criterion as gene vaccine by analysis OD260/280 and electrophoresis. The myostatin expression was detected obviously in transfected CHO. The forelimb grip in immunized mice had an obvious increase. The average value of forelimb grip of the mice immunized with pVAC-TT-Ms was about 29.88% greater than that of control mice.

CONCLUSIONThe construction of eucaryotic expression vector of myostatin coupled TT epitope is successful in expression for recombinant human mature peptide of myostatin. The gene vaccine of myostatin meet quality criterion. The immunized mice has an obvious increase in forelimb grip.

Animals ; CHO Cells ; Cricetinae ; Cricetulus ; Epitopes, T-Lymphocyte ; Genetic Vectors ; Hand Strength ; Humans ; Male ; Mice ; Mice, Inbred BALB C ; Muscle, Skeletal ; physiology ; Myostatin ; genetics ; immunology ; Plasmids ; Transfection ; Vaccines, DNA ; genetics ; immunology

Animals ; Cholelithiasis ; genetics ; Cholesterol ; metabolism ; Cholesterol 7-alpha-Hydroxylase ; genetics ; Genetic Predisposition to Disease ; Hydroxymethylglutaryl CoA Reductases ; genetics ; Liver ; enzymology ; Male ; Mice ; Mice, Inbred AKR ; Mice, Inbred C57BL ; Receptors, LDL ; genetics ; Sterol O-Acyltransferase ; genetics

This study aimed to explore the characteristics and the influencing factors of Qingkailing injection (QKLI) pseudoallergic reaction, and screen out the possible pseudoallergenic substances. The results showed that ICR and Kunming mice had stronger pseudoallergic reactions than BALB/c and C57 mice after being injected with the same dose of QKLI. The pseudoallergic reaction induced by QKLI that was prepared with 0.9% saline was stronger than that prepared with 5% glucose. When the dose was twice of the clinical dose, some batches of QKLI could cause significant or suspected pseudoallergic reactions; when the dose dropped to clinically equal times, all of the batches did not induce pseudoallergic reactions in mice. Different batches of QKLI induced different pseudoallergic reactions in mice. Therefore, QKLI's pseudoallergic reactions might have a certain relationship with different body constitutions. Different solvents might affect the safety of QKLI. QKIL-induced pseudoallergic reactions had the different characteristics between batches, and the dosage should be strictly controlled in clinical use. After the comparison of pseudoallergic reactions induced by different components and different intermediates of QKLI in mice, it was preliminary believed that pseudoallergenic substances might exist in intermediate Isatidis Radix extracts and Gardenia extracts, but specific pseudoallergens shall be furthered studied in subsequent experiences.
Animals ; Drug Hypersensitivity ; Drugs, Chinese Herbal ; adverse effects ; Injections ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Mice, Inbred ICR

Inducible costimulatory molecule (ICOS), a CD28 family member expressed on activated T cells, plays an important roles in T cell activation and effector function. This study was purposed to investigate the effect of blocking ICOS-B7h signal pathway by ICOS-Ig fusion protein on allogeneic reactive T cells and its mechanism. CHO cells stably and highly expressing ICOS-Ig were established, while the human ICOS-Ig fusion protein was harvested and purified from supernatant of CHO cells transfected with pSecTag2/Hygro A-ICOS-Ig. The CD4(+) cells from spleen of C57BL/6 mice were used as reactive cells, the bone marrow derived dendritic cells (DCs) from BALB/C mice were used as stimulatory cells, these cells were treated with different concentrations of ICOS-Ig or human Ig (h-Ig) as control. The results showed that the target protein with molecular weigh 54 kD and endotoxin level < 10 EU/ml was gained. The ICOS-Ig (> or = 10 microg/ml) could significantly inhibited the proliferative effect of allogeneic reactive T cells resulting from stimulation of DCs (p < 0.01). ICOS-Ig did not influence the activation of CD4(+) T cells. ICOS-Ig concentration positively related to the apoptosis of CD4(+) T cells. The percentages of CD4(+) Annexin V(+)PI(-) cells in simple stimulated group, ICOS-Ig 10 microg/ml group and ICOS-Ig 20 microg/ml group were 15.1%, 26.4% and 33.6% respectively. ICOS-Ig decreased secretion of TNFalpha and increased secretion of IL-4. It is concluded that the ICOS-Ig fusion protein has bioactivity of inhibiting T cell proliferation and altering the polarization of T helper cells to Th2 cells which promotes the apoptosis of allogeneic reactive T cells but had no effect on the activation of allo-reactive CD4(+) T cells.
Animals ; Antigens, Differentiation, T-Lymphocyte ; pharmacology ; Apoptosis ; drug effects ; CD4-Positive T-Lymphocytes ; drug effects ; immunology ; metabolism ; CHO Cells ; Cell Proliferation ; drug effects ; Cricetinae ; Cricetulus ; Inducible T-Cell Co-Stimulator Protein ; Interleukin-4 ; secretion ; Lymphocyte Activation ; immunology ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Recombinant Fusion Proteins ; pharmacology ; Signal Transduction ; Th1 Cells ; drug effects ; immunology ; metabolism ; Th2 Cells ; drug effects ; immunology ; metabolism

FTY720 is a synthetic compound derived from the metabolites of Isaria sinclairii. Its unique chemical structure and mechanism appear to be distinctive from other known immunosuppressors. In the present study, the effect of FTY720 on immunosuppression and toxicity to heart was evaluated by detection of lymphocytes count, heart rate in rats, the survival time of the allografts of skin slice in mice and binding to S1P1 and S1P3 receptors by confocal. The results showed that FTY720 could induce lymphopenia, reduce the heart rates in rats and prolong the survival time of the allografts of skin slice in mice. The assay results on confocal showed that FTY720 can bind with S1P1 and S1P3 on surface of CHO-S1P1 and CHO-S1P3 cells. FTY720 could be developed for wide application for organ transplantation and self-immunity diseases.
Animals ; Cricetinae ; Cricetulus ; Female ; Fingolimod Hydrochloride ; Graft Survival ; drug effects ; Heart Rate ; drug effects ; Immunosuppressive Agents ; pharmacology ; Lymphocyte Count ; Lymphocytes ; cytology ; drug effects ; Lymphopenia ; chemically induced ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Microscopy, Confocal ; Propylene Glycols ; pharmacology ; Protein Binding ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Lysosphingolipid ; agonists ; metabolism ; Skin Transplantation ; Sphingosine ; analogs & derivatives ; pharmacology ; Transplantation, Homologous

BACKGROUND: Hantavirus are widely distributed in rodents populations even in geographical areas where hemorrhagic fever with renal syndrome (HFRS) has not been reported. Multiple species of Murid and Arvicolid rodents serve as the natural reservoirs of hantaviruses. Serologic diagnosis using hantaviral antigens indicates that hantaviruses are widely distributed in wild rodents. This study was designed to find the distribution of hantaviruses among wild rodents and small mammals in Korea, 1995-1996. METHODS: Rodents were trapped alive in selected areas. A total of 551 wild rodents from 7 species and 97 small mammals from 4 species were captured in Korea. Serologic evidence for hantavirus infection were tested using five hantavirus antigens by indirect immunofluorescent antibody technique (IFA). Among 162 Apodemus agrarius, 23 Apodemus peninsulae, 8 Clethrionomys regulus, 6 Microtus fortis, 1 Mus musculus, 283 Tamias sibiricus, 68 Sciurus vulgaris, 14 Crocidura laciura, 80 Lepus sinensis, 2 Capereolus capereolus and 1 Nyctereutes procyonoides. RESULTS: 29 A. agrarius, 2 A. peninsulae, 1 C. laciura, 2 C. regulus, 27 T. sibiricus and 7 S. vulgaris were seropositive against Hantaan virus and 7 L. sinensis were IF antibody positive against Seoul virus. Some of Tamias sibiricus were only seropositive against Puumala virus or prospect hill virus. CONCLUSION: This data suggests that new serotypes of hantavirus might distribute among rodents in Korea.
Animals ; Arvicolinae ; Diagnosis ; Hantaan virus ; Hantavirus Infections* ; Hantavirus* ; Hares ; Hemorrhagic Fever with Renal Syndrome ; Korea* ; Mammals ; Mice ; Muridae ; Murinae ; Puumala virus ; Raccoon Dogs ; Rodentia* ; Sciuridae ; Seoul virus

To produce specific monoclonal antibody (McAb) against human thrombomodulin (hTM), the full-length hTM cDNA-expressing plasmid pThr402 was transfected into CHO cells by Lipofectamine 2000 reagent. The hTM-expressing CHO cells, which was confirmed by flow cytometry and Western blot, were obtained by G418 selection. Then the McAb against hTM was prepared with classic hybridoma technique. A cell line of CHO-TM5 with high level of hTM was used to immunize female Balb/c mice 3 times at an interval of 4 weeks. On the third day after the third immunization, mice were sacrificed and spleen cells were harvested to prepare hybridoma cells with SP2/0 cells at the ratio of 10 to 1. Hybridoma cells were then cultured at 96-well plates for screening. Cellular enzyme-linked immunoabsorbent assay (CELISA) was applied twice. The first CELISA was done with polythene ELISA plate with a monolayer of CHO-TM5 cells. The positive clones from the first screen were then selected by reacting with similar screening ELISA plate but with CHO cell monolayer instead. Only clones that were positive for the first screening and negative for the second screening were kept, and called as CHO-TM5(+)CHO(-) hybridoma cells. Balb/c mice were intraperitoneally injected with the selected hybridoma cells. Ascites were collected and monoclonal antibodies were purified using FPLC, and its Ig class, subclass, and titer were then determined respectively. The specificity of the yielded McAb was identified with CELISA, flow cytometry, ABC immunohistochemistry and immunoblotting. One line of hybridoma cells with high expression of specific McAb against hTM, NH-1, was obtained. The Ig subclass of the McAb was IgG1 and the titer of ascitic McAb was 1x10(-6). Flow cytometry, CELISA and Western blot assays demonstrated that McAb NH-1 could specifically recognize hTM expressed in CHO-TM5 cells and human umbilical vascular endothelial cells. Meanwhile, the tissue specificity of antigen recognized by McAb NH-1 was identified by immunohistochemical ABC staining. NH-1 can specifically recognize the natural hTM expressed mainly in vascular endothelial cells, which will potentially be useful for investigation of the functions and clinic values of hTM.
Animals ; Antibodies, Monoclonal ; biosynthesis ; immunology ; Antibody Specificity ; CHO Cells ; Cricetulus ; Female ; Humans ; Hybridomas ; secretion ; Mice ; Mice, Inbred BALB C ; Thrombomodulin ; immunology ; Transfection

OBJECTIVETo explore the influence of chemosensitivity of Tca8113 cells by modified MTT assay after the animal model of Tca8113 were treated by the ultrasound hyperthermia.

METHODSThe MTT assay of the BALB/C nu/nu mice model of Tca8113 cells treated by the ultrasound hyperthermia in vivo was performed.

RESULTSThe chemosensitivity to the 9 kinds of drugs demonstrated no significant differences between the Tca8113 cells in the control group, the 39 degrees C-treated group and the groups treated from 41 degrees C to 44 degrees C. But significant differences between the 40 degrees C-treated group and the 41 degrees C or 42 degrees C-treated group existed. In the heating-time grades test, there were no significant differences in the chemosensitivity to the 9 kinds of drugs between these three pairs of group (the control group and the 15 min-treated group, the 30 min-treated and the 45 min-treated group, the 60 min-treated and the 75 min-treated group). But there were significant differences between the 30 min-treated or the 45 min-treated group and the 60 min-treated or the 75 min-treated group.

CONCLUSIONUltrasound hyperthermia performed in 42 degrees C for 30-45 min can improve the chemosensitivity of Tca8113 cells to some drugs significantly, which confirms the rationality of synchronous combination of hyperthermia and chemotherapy in the chemosensitivity point of view for the first time.

Animals ; Antineoplastic Agents ; Heating ; Hyperthermia, Induced ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Mouth Neoplasms