1.The role of Siglec-1 in chemokines secretion and phagocytosis of oxidized low-density lipoprotein on macrophages
Yisong XIONG ; Chang LI ; Yi SUN ; Renqian ZHONG
Chinese Journal of Laboratory Medicine 2010;33(7):691-696
Objective By in vitro culture of mouse macrophage cell line RAW264. 7 and primary mouse bone marrow macrophages, the expression of Siglec-1 when stimulated by ox-LDL was observed. Meanwhile, Siglec-1 was up-regulated by M-CSF and down-regulated by small interference RNA targeting Siglec-1 ( si-RNA-Siglec-1) , and the expression of chemokines and lipid uptake ability by macrophages were observed, to explore the role of Siglec-1 on macrophages in atherosclerosis. Methods LDL was oxidized by copper. According to preliminary experiment results, ox-LDL 100 μg/ml was selected as a stimulus. There were 6 experimental groups:normal control group,ox-LDL 100 μg/ml group, ox-LDL 100 μg/ml + si-RNA 2509 2 ng/ml group,ox-LDL 100 μg/ml + si-RNA 3618 2 ng/ml group,ox-LDL 100 μg/ml + M-CSF 5 ng/ml group and ox-LDL 100 μg/ml + M-CSF 10 ng/ml group. si-RNA-Siglec-1 was transfected into macrophage to inhibit the expression of Siglec-1, whereas M-CSF 10 ng/ml or 5 ng/ml were added into the culture medium to enhance the expression of Siglec-1. Quantitative real-time polymerase chain reaction ( qRT-PCR) was used to determine the interfere efficiency of si-RNA-Siglec-1 or M-CSF. After stimulation with ox-LDL for 48 h, cell culture supernatants were collected to determine MIP-1 alpha, MCP-1 and IL-8 concentration by ELISA (n =3 for each group) to evaluate the activation of macrophages. Internalization of lipid particles by macrophages was analyzed by oil red 0 staining. Results Observed by fluorescence microscope, si-RNA-Siglec-1 could be effectively transfected into macrophages with a transfection efficiency about 90% ;PCR results showed that si-RNA 2509 and si-RNA 3618 in a concentration of 40 pmol/L had an inhibition rate of 0. 54 ±0. 11 or 0. 52 ±0. 16 vs 1. 00 ±0. 24 (control group) , t =5. 227 and 4. 992, respectively, all P < 0.01, while M-CSF 10 ng/ml could increase Siglec-1 mRNA expression approximately 4-fold (4. 16 ± 1. 25 vs 1.00 ±0. 24, t =7. 448, P<0. 01). The secretion of MCP-1, MIP-1 alpha, and MIP-2 in si-RNA3618-Siglec-1 group [(359. 28±47. 80) pg/ml, (33. 76 ± 14. 28) ng/ml and (7.87±1.55) ng/ml for MCP-1,MIP-1 alpha, and MIP-2, respectively] was significantly reduced in compare with ox-LDL 100 μg/ml group [ (577. 89 ± 35. 95 ) pg/ml, (69. 17 ± 11. 82) ng/ml and (12.28 ± 1.19) ng/ml for MCP-1, MIP-1 alpha, and MIP-2, respectively], with P value of 0.01, 0.05 and 0.01. In contrary, ox-LDL 100 μg/ml plus M-CSF 10 ng/ml group could significantly promote macrophage chemokine secretion [ (672. 89 ± 43.80) pg/ml, (101.31 ±24.17) ng/ml and (14.81 ±0.54) ng/ml for MCP-1, MIP-1 alpha, and MIP-2, respectively], with P < 0.05 compared with ox-LDL 100 μg/ml group. Meanwhile, lipid intemalization and foam cell formation was inhibited in si-RNA3618-Siglec-l group while ox-LDL 100 μg/ml plus M-CSF 10 ng/ml group could enhance the phagocytosis of ox-LDL by macrophage. Conclusions Siglec-1 may served as a potential phagocytic receptor for ox-LDL involving in macrophage uptake of lipid and turn into foam cells. Furthermore, it can active macrophages and enhance the secretion of MIP-1 alpha, MCP-1 and IL-8, attracting more macrophages and lymphocytes to the site of inflammatory plaque. Targeted inhibition of Siglec-1 reduces macrophage uptake of lipid and secretion of chemokines. Siglec-1 may possibly serve as a potential target of treatment or delay the development of atherosclerosis.
2.Screening differentially expressed proteins of fibroblast-like synoviocytes in rheumatoid arthritis by 2-DE and MALDI-TOF-MS
Xiaoqin ZHAO ; Xiaojun LI ; Jianning ZHAO ; Xiaojuan PANG ; Fangfang CHEN ; Wei YU ; Bing LUO
Chinese Journal of Laboratory Medicine 2010;33(7):625-630
Objective To identify synovium-associated proteins of by analyzing proteome of FLS between RA patients and traumatic arthritis. Methods The total protein of FLS from 3 patients of RA and 6 normal controls were separated by 2-DE. The differentially expressed proteins were identified by MALDI-TOF-MS. Results The 2-DE image results showed that there were many proteins differentially expressed in FLS from RA and control. A total of 33 differential proteins that were up-regulated in RA as compared with controls were selected and 30 proteins including pyruvate kinase isozymes M1/M2, α-enolase, protein disulfide-isomerase A3 precursor, glutathione transferase, peroxiredoxin 1, ubiquitin-conjugating enzyme E2K, platelet-activating factor acetylhydrolase IB, dihydropyrimidinase-related protein 2, adenosine kinase, transaldolase, δ-δ-dienoyl-CoAisomerase, 26S protease regulatory subunit 6A, annexin All, tryptophanyl-tRNA synthetase isoform b, lamin-A/C, myomesin-1 isoform b, ruvB-like 1, actin-cytoplasmic 1, T-complex protein 1, stress-70 protein, mitochondrial precursor, α-crystallin B chain, 78 000 glucose-regulated protein, PSME4, SELENBP1 and so on. Conclusion The differentially expressed proteins are present in FLS from RA and control, which may be the synovium biomakers and involved in pathogenesis of RA.
3.Study of molecular mechanisms of hereditary protein C deficiency in four Chinese families
Yingting WU ; Qiulan DING ; Jing DAI ; Yeling LU ; Xiaodong XI ; Xuefeng WANG ; Hongli WANG
Chinese Journal of Laboratory Medicine 2010;33(7):599-605
Objective To investigate the phenotype, genotype and molecular mechanisms in four Chinese pedigrees with venous thrombosis caused by hereditary PC deficiency. Methods The plasma activity of PC: A, TPS: A and FPS: A of the probands and their family members were detected with chromogenic and coagulation assay. The antigen of PC and FPS were identified with ELISA. Thrombin generation tests were applied to indicate the coagulation status. All of the nine exons and intron-exon boundaries of PC gene and PS gene were amplified by PCR and directly sequenced for mutaiton investigation. Results Compound heterozygous mutations of L-34P, K150del and A209V with 36% of PC: A and 57% of PC: Ag were identified in proband 1. PC: A was 46% , PC: Ag was 64. 4% while TPS: A, FPS: A and FPS: Ag were 36% , 19.5% and 20.9% respectively in proband 2. Two independent heterozygous mutations of R147W in PC gene inherited from his mother and T519stop in PS gene inherited from his father were identified. The anticoagulant activity of Proband 2 and his parents were declined in thrombin generation assay. In proband with PS defeciency and his father, the inhibition of thrombin generation capacity was decreased with exogenous APC, while his mother did not have significant difference. In Proband 3, PC: A was 32% while PC: Ag was 48.42% . Two independent mutations of R147W and R178W in Exon 7 were detected. Compound heterozygous mutations of R178W and D255H,with 21% of PC : A and 18. 36% of PC: Ag were identified in the Proband 4. Conclusions Hereditary PC deficiency or combined PC and PS deficiency result in venous thrombosis in four Chinese families. Mutants of L-34P, A209V, R178W, R147W and D255H might be the molecular mechanisms of PC deficiency.
4.Determination of serum betaine by high performance liquid chromatography
Ying CHANG ; Bingyan TAN ; Lin ZHENG ; Shiwei Lü ; Huilian ZHU
Chinese Journal of Laboratory Medicine 2010;33(5):405-408
Objective To establish a novel method for the determination of betaine in serum by high performance liquid chromatography with UV detection.Methods Pre-column derivatization of serum was performed directly in acetonitrile without extraction with p-bromophenacyl bromide and 18-crown-6 ether as catalyst.The p-bromophenacyl ester derivatives were then separated by Supelcosil LC-SCX, using an was 0.8 ml/min and the effluent was monitored at 259 nm. Betaine was used for preparation of standard curve and quantification with external standards.Results The linearity of this method was 6.25-200.00 μmol/L,the regression was 0.999 8.The detection limit was 3.0 μmol/L.The within-day imprecision was 1.88%-3.79% ( average 3.24% ), the between-day imprecision was 3.14%-6.76% ( average 4.39% ), the recovery rates were 95.89%-102.86% (average 99.16% ).Conclusion This method is sensitive, rapid, accurate and suitable for the research and routine clinical practice.
5.Serum cholesteryl ester n-3 fatty acid analysis by high performance liquid chromatography
Ruifang CUI ; Jun DONG ; Weiyan ZHOU ; Hanbang GUO ; Hongxia LI ; Yong MAN ; Shu WANG ; Wenxiang CHEN
Chinese Journal of Laboratory Medicine 2010;33(5):400-404
Objective To develop an HPLC method for the measurement of n-3 fatty acid index of serum cholesteryl esters.Methods Serum triglycerides were hydrolyzed with ethanolic sodium hydroxide and cholesteryl esters (CEs) were extracted with hexane.The extracted CEs were analyzed by reversed phase HPLC with a UV detection at 205 nm.Cholesteryl eicosapentaenoate and docosahexaenoate ( major n-3 fatty acid cholesteryl esters) were identified by liquid chromatography-tandem mass spectrometry and cholesterol in each CE fraction was measured.Peak areas of CEs were corrected for cholesterol and CE n-3 index was calculated using the corrected peak area and expressed as the percentage of n-3 fatty acid CEs in total CEs.Results The HPLC analysis can be finished in 6 minutes.Triglycerides which interfere with the determination of n-3 fatty acid index, were hydrolyzed with ethanolic sodium hydroxide (4 mol/L) in 30 seconds.The within-run and total CVs for CE n-3 index averaged 0.66% and 0.90%, respectively.CE n-3 indexes of 70 volunteers and 36 coronary heart disease patients apparently healthy subjects and patients with coronary heart disease in Beijing Hospital appeared to be positively skewed and leptokurtic distribution ( skewness = 1.25, kurtosis = 1.70 ).The median of n-3 indices were 0.98% ( 0.37% - 2.40% ).The logarithm of n-3 index appeared to be normal distribution and the average is 0.003 7% with standard deviations of 0.15.The distribution of n-3 indices of gender groups was similar with the total.The medians of females and males were 1.08% (0.60% -2.40%) and 0.95% (0.37% -2.11%) respectively, and the former were significantly higher than the latter( t = - 3.021, P = 0.003 ).Conclusion A new method for the measurement of n-3 index of serum cholesteryl esters by HPLC has been established.It is simple and precise and can be used in predicting cardiovascular diseases risks and monitoring dietary intake of n-3 fatty acids.
6.Management of point-of-care testing glucose monitoring program in hospital in the JCI accreditation
Jie WANG ; Jian CHEN ; Yuan Lü
Chinese Journal of Laboratory Medicine 2010;33(5):392-394
Point-of-care testing (POCT) of blood glucose has been widely used for continuous monitoring of glucose in clinic due to high sensitivity, convenience, accessibility and shorter TAT.It has been developed rapidly in recent years. But glucose POCT is often out of control and management from central laboratory and usually it was performed by non-laboratorians.It becomes the growing concerns that how to avoid the discrepancy between POCT results and central laboratory results, how to ensure POCT quality of each batch of blood glucose results, how to solve issues in the application and ensure that patients' results are accurate and reliable. The hospital should put the POCT management under the whole management system and improve the accuracy of POCT to achieve the complete quality assurance. This article introduced the management program experiences of glucose POCT in Huashan hospital according to the JCI accreditation and CAP-LAP.
7.Evaluation of coagulation in vitro with platelet mapping and rapid TEGTM on thrombelastography
Jian LI ; Yulong CONG ; Zulan LI ; Li YANG ; Chengbin WANG ; Furong LEI
Chinese Journal of Laboratory Medicine 2010;33(5):453-456
Objective To evaluate performance of PlateletMapping(R) and RapidTEGTM based on thrombelastography by blocking platelet function with Reopro.Methods PlateletMapping was carried out with whole blood from healthy volunteers mixed with Reopro in vitro in a serial of titration.TEG(R) ACT of heparinized blood was tested with Rapid TEG kits.Linearity, repeatability and validity were calculated for two methods.Results MA activated by Kaolin, AA and ADP decreased with the increase of the concentration of Reopro. Inhibition rates (%)for AA and ADP induced aggregation were repeatable in channels and systems.At the Reopro levels of (1-4) × 10-2 mg, inhibition rate increased statistically( AA:27.99% ± 2.8% vs 63.37% ± 0.0% ,t = 21.9, P < 0.01;ADP: 35.9% ± 0.56% vs 91.42% ± 1.14%,t=58.9,P < 0.01 ) after addition of Reopro.Dose-dependent effect relationship could be seen between TEG(R) ACT and heparin;In Rapid TEG assay, measurement repeatability of K, α angle, MA and TEG(R)ACT were all good ( CV < 5% ) except for R.Conclusions PlateletMapping(R) is sensitive to the inhibition of platelet function with good precision with dose-dependent effect.Moreover, Rapid TEG provides analysis of the overall coagulation function besides monitoring heparin therapy.
8.Cross reaction characteristics of recombinant fusion protein of human papillomavirus 16 type L2
Lingling LI ; Jianxiao LIU ; Shanli ZHU ; Xiangyan XUE ; Jun CHEN ; Lifang ZHANG
Chinese Journal of Laboratory Medicine 2010;33(5):435-440
Objective To investigate the cross reaction characteristics of recombinant human papillomavirus 16 type L2 full-length fusion protein in HPV types of 6, 11, 18.Methods The serum samples of 108 condyloma acuminatum patients, 156 cervix cancer patients and 100 healthy control subjects were collected.The gene of full-length HPV16 L2 was amplificated from the tissue DNA of cervical cancer patient and inserted into the prokaryotic expression vector PGEX-4T-1 to construct the recombinant plasmid PGEX-4T-1-HPV16 L2.After sequencing identification, the recombinant plasmid was tranformed into E.coli BL21 (DE3).After induction by IPTG, the fusion protein containing HPV16 L2 was expressed and analyzed by both SDS-PAGE and WB.Furthermore, the specific binding capacity of the fusion protein to the HPV 6,11, 16 and 18 DNA positive patient's sera were analyzed by WB.The fusion protein was purified with NiNTA Agarose Kit and coated with ELISA reaction plates.The specific serum IgG were detected by indirect ELISA.Results The recombinant plasmid PGEX-4T-1-HPV16 L2 was constructed successfully. Highly expressed HPV16 L2 full-length fusion protein was obtained and the expression level was 27.2 %.The relative molecular mass(Mr) of the fusion protein is about 82 × 103, which matches up to the expected Mr.Meanwhile, the sera of HPV 6,11,16,18 DNA positive patients were used as the primary antibody and the Mr of the specific band was detected to be about 82 × 103 by WB.The results of indirect ELISA showed that the average levels of specific IgG in condyloma acuminatum group, cervical cancer group and healthy control subjects were 0.848 ±0.257, 0.822 ±0.247 and 0.173 ±0.143 with the positive rate of 92.6%, 94.2%and 8.0% respectively.There was no significance of the specific IgG levels between condyloma acuminatum group and cervical cancer group ( F = 0, P > 0.05 ), but there was significant difference of specific IgG levels and positivity among the three groups ( F = 305.201 ,x2 = 253.178, P < 0.01 ).Conclusions The HPV16 L2 full-length fusion protein has better antigenicity.However cross reactions with HPV6, 11 and 18 were found.It can be applied in serological screening reagents for HPV infection and associated cancer.
9.The preparation of quality control materials for human papillomavirus genotyping
Jie HUANG ; Shoufang QU ; Ren XU ; Shangxian GAO
Chinese Journal of Laboratory Medicine 2010;33(6):559-562
Objective To prepare the HPV genotyping control materials. Methods Three hundred cervical smears with different HPV genotypes were collected and detected by surface plasmon resonance and sequencing. The primers for specific genotype were designed according to GenBank. The recombinant plasmid was constructed through PCR amplification, ligation and transformation. Thirty recombinant plasmids were identified through PCR amplification, sequencing, and the sequences were compared using BLAST. Results The collected HPV infectious samples contained 30 different genotypes including HPV 6,16,18 and so on.The fragment sequences of PCR amplification were concordant with the designed. The fragment sizes of the other types ranged from 1 500 to 2 000 bp except HPV CP8304. And the 30 recombinant plasmids identified by PCR were concordant with the target. The identity of BLAST was 99%. In the fragment of 1500 bp in length, 11 bases were inconsistent with the reference sequence. Conclusions Genotyping control materials were developed successfully. The human papillomavirns genotyping control materials covered all the most common types and included 14 types with high-risk, 3 types with medium-risk and 13 types with low-risk.
10.Evaluation for the treatment efficacy for cryptococcus neoformans meningitis by VAD1 mRNA detection with real-time fluorescent quantitative polymerase chain reaction
Ling JIANG ; Wen LI ; Qishui OU
Chinese Journal of Laboratory Medicine 2010;33(6):531-534
Objective To establish a new approach for quantitative detection of VAD1 mRNA in cryptococcus neoformans by RT-FQ-PCR, and evaluate the treatment efficacy of CNM. MethodsThe primers and TaqMan probe were designed according to the published sequence of VAD1 mRNA (GenBank),and RT-FQ-PCR method to detect VAD1 mRNA was established. Cerebrospinal fluid from 25 CNM patients and 30 controls were detected and sensitivity and specificity of the method were evaluated. VAD1 mRNA concentration in cerebrospinal fluid from both acute phase and recovery phase of 25 CNM patients were also detected and significance of CNM treatment efficacy with VAD1 mRNA analysis was evaluated. Results Correlation coefficient of standard curve was - 0. 997 9 in detection of VAD1 mRNA by RT-FQ-PCR, and the detection limit was 101 copies/μl. The intra CV of plasmid standard for high, medium and low concentrations were 0. 65% ,0. 89% and 1.23% respectively, the sensitivity of cryptococcus neoformans detection by RT-FQPCR was 96% (24/25) ,while specificity was 100% (30/30). VAD1 mRNA concentration in acute phase were significant higher than that in recovery phase (3. 042 ±0. 906 vs 2. 187 ±0. 665 ,t =4. 583 ,P <0. 01).Conclusions The established RT-FQ-PCR method for the detection of VAD1 mRNA is provided with sound sensitivity, specificity and reproducibility, which might be fit for the detection of VAD1 mRNA. The expression level of VAD1 mRNA is relevant with the treatment efficacy of CNM.