This study is designed to obtain recombinant human acetylcholinesterase (rhAChE) and apply it in screening acetylcholinesterase inhibitors. The rhAChE was overexpressed in HEK293 cells transfected by plasmid of pCMV-AChE with the cationic liposome and rhAChE was found to be secreted into cell culture medium. AChE activity was assayed according to modified Ellman method to obtain kinetic parameters. IC so50 values for donepezil compounds of rhAChE were calculated to determine their activities of inhibition. The results showed that Km value was 151.9 micromol.L-1 donepezil inhibited rhAChE in a mixed competitive-noncompetitive way (Ki= 16.03 nmol.L-1, Ki = 18.36 nmol.L-1) and that most new compounds tested exhibited high activities of inhibition on rhAChE. The study suggests that rhAChE is available to be applied in screening AChE inhibitors in vitro.
Acetylcholinesterase ; genetics ; metabolism ; Cholinesterase Inhibitors ; analysis ; pharmacology ; HEK293 Cells ; Humans ; Indans ; analysis ; pharmacology ; Inhibitory Concentration 50 ; Kinetics ; Piperidines ; analysis ; pharmacology ; Plasmids ; Recombinant Proteins ; genetics ; metabolism ; Transfection

OBJECTIVETo explore the effects of hippophae juice on free radical metabolism of rat skeletal muscle and partial biomarkers in blood.

METHODSRandomly dividing the 30 SD rats into 3 groups (n = 10): sedentary group, training group and hippophae training group. Measuring related indices of skeletal muscle and blood in rat after 6 week training and hippophae juice supplement.

RESULTSCompared with training group, hippophae training group showed obviously longer exhaustive time, significantly increased antioxidant enzyme in skeletal muscle, remarkably decreased malonaldehyde (MDA) content in skeletal muscle, obviously increased testosterone (T) and hemoglobin (Hb) content in blood, significantly decreased creatine kinase (CK).

CONCLUSIONHippophae juice can impove the antioxidant ability of rat skeletal muscle, the level of T and Hb in blood, delay fatigue, therefore effectively enhance the aerobic stamina of rat.

Animals ; Creatine Kinase ; blood ; Free Radicals ; metabolism ; Hemoglobins ; metabolism ; Hippophae ; Male ; Muscle, Skeletal ; metabolism ; Rats ; Rats, Sprague-Dawley ; Testosterone ; blood

Objective To observe the effects of 75 gram glucose oral tolerance test (75 g OGTT) and standard mixed meal test (SMMT) on insulin secretion function of the islets of Langerhans and plasma free fatty acid (FFA) in patients with type 2 diabetes mellitus.Methods Seventy-six patients with type 2 diabetes without using insulin and with no obvious complications were recruited for 75 g OGTT following overnight fasting on the first day and SMMT (bread 50 g,egg 50 g and milk 250 ml) on the 7th day.Blood specimens were collected from each patients before the tests and 30 min,60 min,120 min and 180 min after glucose or meal load to measure their levels of plasma glucose,serum insulin,C peptide,FFA and lipids (total cholesterol,triglyceride,high-density and low-density lipoprotein cholesterol).Results No difference in fasting plasma glucose,serum insulin,C peptide,FFA and lipids between 75 g OGTT and SMMT was found.Postprandial plasma glucose 30 min,60 min,120 min and 180 min after 75 g OGTT was significantly higher than that after SMMT,with (15.3?3.5) vs (9.9?3.4) mmol/L,(18.2?4.8) vs (12.8?4.0) mmol/L,(16.3?5.8) vs (12.2?4.9) mmol/L and (10.6?5.4) vs (9.5?4.5) mmol/L (F=28.1,P

BACKGROUNDThe B7/CD28 pathway provides critical costimulatory signals for complete T cell activation, and members of this pathway have served as useful targets for immunotherapeutic strategies. In this study, we investigated the RNA interference (RNAi) effect induced by small interfering RNA (siRNA) targeting CD28 mRNA on human lymphocytes and its specificity.

METHODSAccording to CD28 gene sequence, we designed and synthysized three different siRNAs (siRNA-1, siRNA-2, siRNA-3) containing 21 bases using Silencertrade mark siRNA construction kit. These siRNAs were transfected into freshly isolated human lymphocytes with Lipofectamine 2000 reagent. At 24-hour, 48-hour and 72-hour post transfection, these cells were collected and analyzed. The changes of surface expression of CD28 gene were detected by flow cytometry, and the changes of CD28 mRNA levels were determined by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). The cell viability of transfected lymphocytes was determined by methyl thiazolyl tetrazolium (MTT) assay and trypan blue dye exclusion assay.

RESULTSThree siRNAs (siRNA-1, siRNA-2, siRNA-3) specifically targeting CD28 mRNA were successfully designed and constructed. Flow cytometry analysis showed that a decrease in CD28 expression was detectable at 24-hour post transfection. Different siRNA showed different inhibition effects on CD28 expression. At 48-hour post transfection, the degrees of reduction with siRNA-1, siRNA-2 and siRNA-3 were 22.10% +/- 1.63%, 73.50% +/- 1.02% and 42.90% +/- 0.89% respectively compared with the control (P < 0.001). Neither of the groups transfected only with siRNA or lipo showed marked reduction in CD28 expression (3.15% +/- 0.75% and 4.55% +/- 0.80%) (P > 0.05). Moreover, lymphocytes treated with siRNA-co showed no marked reduction in CD28 expression (5.07% +/- 0.96%) (P > 0.05). The results of semi-quantitative RT-PCR assay indicated CD28 mRNA level was inhibited after transfection of specific siRNAs. At least 4-fold of reduction in siRNA-2 group occurred at 48-hour post transfection compared with the control (P < 0.001). MTT assay and trypan blue dye exclusion assay demonstrated that the viable cell rations of transfected lymphocytes were significantly reduced in siRNA-1, siRNA-2 and siRNA-3 groups at 48-hour post transfection (P < 0.01). The control groups showed no marked reduction in cell viability (P > 0.05).

CONCLUSIONSThree different siRNAs were synthesized and transfected into lymphocytes. They could reduce the expression of CD28 and the CD28 mRNA level. siRNA-2 was the most efficient. The cell viability reduced correspondingly. Therefore, the silencing effect on CD28 mRNA induced by siRNA may contribute to costimulatory blockade. This result show that siRNA may be useful for further study on graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (allo-BMT).

Adolescent ; Adult ; CD28 Antigens ; genetics ; Cell Survival ; Cells, Cultured ; Flow Cytometry ; Gene Silencing ; Humans ; Lymphocytes ; metabolism ; RNA, Small Interfering ; pharmacology ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo construct a recombinant lentiviral vector (pXZ208-BDDhFVIII) mediating B-domain-deleted human coagulation factor VIII (BDDhFVIII) gene and investigate its expression in HLF, Chang-Liver and MSC cells.

METHODSBDDhFVIII gene fragment was separated by endonuclease digestion and was cloned into the multiple cloning sites of pXZ208 to construct a recombinant lentiviral vector pXZ208-BDDhFVIII. Viral particles were prepared by means of three-plasmid cotransfection of 293T package cells by calcium phosphate precipitation. After infection, the coagulant activity of human FVIII in the culture medium of 293T, HLF, Chang-Liver and MSC cells was assayed by one-stage method. The gene transduction efficiency was assayed by flow cytometry (FCM). Furthermore, PCR was performed to test the integration of BDDhFVIII.

RESULTSThe infection rates of HLF, Chang-Liver and MSC were (74.52 +/- 7.57)%, (27.24 +/- 6.53)% and (42.34 +/- 5.84)% respectively. The activities of FVIII in supernatants of HLF, Chang-Liver and MSC were (54.1 +/- 5.6)%, (22.5 +/- 2.9)% and (12.5 +/- 2.7)% respectively. BDDhFVIII gene integration was detected in all the infected cells.

CONCLUSIONThe recombinant lentiviral vector pXZ208-BDDhFVIII was successfully constructed and efficiently integrated into target cells to express human FVIII activity in vitro.

Cell Line ; Factor VIII ; biosynthesis ; genetics ; metabolism ; Gene Expression ; Genetic Vectors ; Humans ; Lentivirus ; genetics ; Plasmids ; Transfection

This study was aimed to propagate and identify the prdm1 gene-knockout mice, so as to lay the foundation for studying Blimp-1 protein. Two kinds of transgenic homozygous mice with B6.prdm1(flox/flox) and B6.Lck-Cre were feed and propagated; after successful propagating, the first passage mice were obtained; after the first passage mice were copulated once again, the genotypes were obtained as follows: B6. prdm1(wild/wild). Lck-Cre, B6. prdm1(wild/wild), B6.prdm1(flox/flox). Lck-Cre, B6.prdm1(flox/wild). Lck-Cre, B6.prdm1(flox/flox), B6. prdm1(flox/wild). The genomic DNA of second passage mice was extracted, the Cre and loxp gene fragments were amplified by PCR, then the size of Cre and loxp genomic DNA were detected by agarose gel electrophoresis. The mice with B6.prdm1(flow/flox). Lek-Cre were used as conditionally prdm1-knockout mice, B6.prdm1(flox/wild). Lck-Cre mice, B6.prdm1(flox/flox) and B6 mice were used as controls. The spleen T lymphocytes and B lymphocytes were sorted by using magnetic beads, the blimp-1 target protein was identified by Western blot. The results showed that the two transgenic homozygous mice had the ability to reproduce, and the separation ratio of second passage mice generated from propagation of their offspring cach other meet Mendelian laws, and the prdm1 gene-knockout mice also could successfully obtained. It is concluded that the application of Cre-loxp system may successfully obtain plentiful prdm1 gene-knockout mice.
Animals ; Genotype ; Mice ; Mice, Inbred C57BL ; genetics ; Mice, Knockout ; genetics ; Reproduction ; Transcription Factors ; genetics

OBJECTIVETo explore the prophylaxis effect of pretreatment of allograft with methoxypolyethylene glycol-succinimidyl-propionic acid ester (mPEG-SPA) and anti-OX40L monoclonal antibody (McAb) on acute graft-versus-host disease (aGVHD) after allogeneic bone marrow transplantation (allo-BMT) in mice.

METHODSResponder splenocytes from C57BL/6 donor mice (H-2(b)) were co-cultured with stimulator splenocytes from BALB/c recipient mice (H-2(d)) for 7 days in the presence or absence of anti-OX40L McAb followed by mPEG-SPA chemical modification. Donor bone marrow cells plus the mixed culture of T-cells were then transplanted into lethally irradiated BALB/c mice. The BALB/c recipient mice were divided into four groups: group A (allo-BMT control group), group B(mPEG-SPA modification group), group C (anti-OX40L McAb pretreated group) and group D (mPEG-SPA and anti-OX40L McAb dual-treated group). Survival time and survival rate of the recipients were observed after allo-BMT. GVHD was assessed by clinical signs and histological changes of skin, liver and small intestines. Enzyme-linked immunosorbent assay (ELISA) was used to detect cytokines (IL-4, IL-10 and INF-gamma) production. Flow cytometry (FCM) analysis was used to detect allogeneic chimerism.

RESULTS(1) The mice in group A developed typical clinical signs of aGVHD and all mice died within 17 days after BMT with an average survival time (AST) of (12.1 +/- 5.5) days. The signs of aGVHD were less evident in mice of groups B, C and D, and their AST (36.2 +/- 24.9, 32.0 +/- 24.8 and 44.3 +/- 23.2 days, respectively) were all longer than that in group A (P < 0.05). AST of group D being the longest (P < 0.05). The survival rates at day 60 post-BMT in groups B, C and D were 50%, 41.7% and 66.7%, respectively. (2) Serum IFN-gamma level was increased after BMT in group A, and peaked in day 10 to day 15 post-BMT, while the level was decreased in groups B, C and D, reached the nadir on the day 10 post-BMT, with the lowest in group D (P < 0.01). After BMT, IL-4 and IL-10 levels were slightly decreased in group A, their levels were elevated in groups B and C (P < 0.05) and even more significantly increased in group D (P < 0.01). IL-4 and IL-10 levels peaked between day 10 and 15 post-BMT. (3) The average proportion of H-2(b) positive cells in recipient mice was 95% - 100% on day 60 post-BMT, with complete donor-type implantation.

CONCLUSIONCombination of mPEG-SPA and anti-OX40L McAb can block T-cell activated antigens and co-stimulatory pathway, regulate the T cells differentiation and induce the immune shift of Th0 cells toward Th2 cells. The immune tolerance induced by this method can significantly relieve aGVHD after allo-BMT.

Animals ; Bone Marrow Transplantation ; Graft vs Host Disease ; prevention & control ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Transplantation, Homologous

OBJECTIVETo prepare the genetic engineering regulatory T cells (Treg) via the self-inactivating (SIN) lentiviral vectors carrying Foxp3 gene, and assay the phenotype and abilities of its proliferation and immunosuppression.

METHODSThe bicistronic SIN lentiviral transfer plasmid containing Foxp3 gene and internal ribosomal entry site-green fluorescent protein gene (IRES-GFP) was constructed. Human embryonic kidney 293T cells were co-transfected using liposome by lentiviral packing system, which included the packaging plasmid Delta NRF, the transfer plasmid and the envelope plasmid VSVG. The efficiency of gene transduction and the expressions of Foxp3, CD25, GITR, CTLA-4 of CD4(+)CD25(-) T cells, which were isolated by magnetic beads from the spleen, and then co-cultured with 293T cells, were detected by flow cytometry (FCM). The proliferative and suppressive capacities of transduced T cells were estimated by Cell Count Kit-8 (CCK-8) and the cytokine production was performed by ELISA.

RESULTSThe lentiviral transfer plasmid pXZ208-Foxp3-IRES-GFP was successfully constructed, the virus titers were above 10(6) IU/ml in the supernatant. pXZ208-IRES-GFP was used as control group. After cocultured, the CD4(+)CD25(-) T cells expressed significantly higher Foxp3, CD25, GITR and CTLA-4 in experimental group than in control group. Upon stimulation with anti-CD3 epsilon and APCs, the proliferative capacity of Foxp3-transduced T cells and the production of IL-2, IL-4, IL-10, IFN-gamma were significantly lower than those in control group (P < 0.01); Foxp3-transduced T cells also significantly inhibited the proliferation of CD4(+)CD25(-) T cells.

CONCLUSIONSThe genetic engineering Treg mediated by SIN lentiviral vectors are successfully constructed and their phenotype and function are similar to natural CD4(+)CD25(+) Treg.

Animals ; Cell Proliferation ; Cells, Cultured ; Forkhead Transcription Factors ; genetics ; metabolism ; Genetic Engineering ; Genetic Vectors ; HEK293 Cells ; Humans ; Lentivirus ; genetics ; Mice ; Mice, Inbred BALB C ; Phenotype ; T-Lymphocytes, Regulatory ; cytology ; immunology ; metabolism ; Transfection

OBJECTIVETo explore the expression of beta protein 1 (BP1) gene in adult acute leukemia (AL) and its relationship with acute leukemia.

METHODSExpression of BP1 gene mRNA was detected in 70 adult AL, 10 normal controls and HEL cell line, by reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTSNo detectable BP1 gene was found in peripheral blood or bone marrow cells of normal controls and 20 acute myeloid leukemia (AML) in complete remission (CR) stage. BP1 gene was highly expressed in HEL cell line, 57% (20/35) of AML and 80% (8/10) of AML-M(5) cases. BP1 gene could not be detected in adult acute lymphoid leukemia.

CONCLUSIONBP1 gene was highly expressed in AML. It might be used as a molecular marker of AML.

Acute Disease ; Adolescent ; Adult ; Female ; Genes, Homeobox ; Globins ; genetics ; Homeodomain Proteins ; genetics ; Humans ; Leukemia ; genetics ; Male ; Middle Aged ; Transcription Factors ; genetics

OBJECTIVETo explore the killing effect of the mutant herpes simplex virus thymidine kinase (HSV-sr39tk) and its wild-type (HSV-tk) mediated by lentiviral vector on T lymphocytes in vitro and compare T cell survival rate after GCV or ACV treatment.

METHODSThe three-plasmid lentiviral vector system including packaging plasmid DeltaNRF, envelope plasmid VSV-G and vector plasmid (pTK151 + HSV-sr39tk or pTK151 + HSV-tk) were cotransfected into human embryonic kidney 293T cells using modified calcium phosphate precipitation methods. The packaged virus was harvested 72 h later. The survival of T cells expressing HSV-sr39tk or HSV-tk was measured by MTT assay after 4 day-culture against a gradient of GCV or ACV concentrations.

RESULTSThe three plasmids were effectively cotransfected and a high titre of lentivirus was obtained (2 x 10(6) IU/ml). 39tk(+) T cell survival rates declined promptly when the prodrug GCV/ACV concentrations increased from 0 micromol/L to 10 micromol/L. The T cell survival rates in GCV group declined from (96.04 +/- 3.23)% to (36.76 +/- 4.38)% while in ACV group from (97.31 +/- 4.61)% to (43.75 +/- 8.99)%. However, when GCV/ACV concentrations were more than 10 micromol/L, further decline of 39tk(+) T cell survival rates became unobvious. The growth rate of 39tk(+) T cell exposed to GCV or ACV was obviously lower than that in un-transfected T cells (P < 0.05). Tk(+) T cells were sensitive to GCV (P < 0.05), but not to ACV (P > 0.05). There was a significant difference in killing effects between 39tk(+) T cell + GCV group and tk(+) T cell + GCV group (P < 0.05).

CONCLUSIONThe lentiviral vectors containing HSV-sr39tk gene could infect T lymphocytes effectively and stably without affecting the proliferation of the transduced cell. In contrast to HSV-tk gene, T cells infected HSV-sr39tk were more sensitive not only to GCV but also to ACV.

Acyclovir ; pharmacology ; Animals ; Cell Survival ; drug effects ; Cells, Cultured ; Ganciclovir ; pharmacology ; Genetic Vectors ; Lentivirus ; genetics ; Mice ; Mice, Inbred C57BL ; Plasmids ; genetics ; T-Lymphocytes ; cytology ; drug effects ; Thymidine Kinase ; genetics ; Transfection