Biomedical subjects

Jin Su

Publications and source records attributed to Jin Su.

At least 19 recordsLinked to original sources

PubMed2006

Identification and characterization of major flavonoids and caffeoylquinic acids in three Compositae plants by LC/DAD-APCI/MS.

In this study, a liquid chromatography/diode array detector-atmospheric pressure chemical ionization/mass spectrometry (LC/DAD-APCI/MS) was successfully developed to identify and characterize the main flavonoids and caffeoylquinic acids (CQAs) of three common Compositae plants (Chrysanthemum morifolium Raman, Artemisia annua, and Chrysanthemum coronarium) which have been used as herbal medicine. Identifications were performed by comparing the retention time, UV and mass spectra of samples with standards or/and earlier publications. The crude methanolic extracts of these plants were assayed directly using LC/MS without any further pretreatment. The proposed method is rapid and reproducible and is useful for characterization and evaluation of different plant flavonoids and CQAs. A total of 41 different flavonoids and 6 CQAs were identified and confirmed by APCI-MS. The main components of three Compositae plants were also compared. Although there exist some similarities in the flavonoidic content of the leaf and flower of C. morifolium, significant variations in their varieties and concentrations were observed. Artemisia annua processes substantial amount of alkylated derivatives of flavones and Chrysanthemum coronarium contains only CQAs. These findings suggest that although all the plants studied are from the same Compositae family, their flavonoids and phenolic compositions are markedly different. The proposed method is useful for further chromatographic fingerprinting of plant flavonoids.

Asteraceae↗

PubMed2006

The repression of human differentiation-related gene NDRG2 expression by Myc via Miz-1-dependent interaction with the NDRG2 core promoter.

The N-myc downstream-regulated gene 1 (ndrg1) is highly expressed in N-myc knock-out mice through an unknown regulatory mechanism. As one member of the human NDRG gene family, NDRG2 encodes a protein highly homologous to Ndrg1. However, it is uncertain whether the expression of human NDRG2 is regulated by Myc because mouse ndrg2 and -3 are not affected by Myc. In this study, we provide the novel evidence that the expression of human NDRG2 is down-regulated by Myc via transcriptional repression. A high level of NDRG2 was observed as Myc expression was reduced in differentiated cells, whereas a low level of NDRG2 was shown following increased Myc expression upon serum stimulation. The ectopic expression of c-Myc dramatically reduces the cellular Ndrg2 protein and mRNA level. We further identified the core promoter region of NDRG2 that is required for Myc repression on NDRG2 transcription, and we verified the interaction of Myc with the core promoter region both in vitro and in vivo. Moreover, the c-Myc-mediated repression of NDRG2 requires association with Miz-1, and possibly the recruitment of other epigenetic factors, such as histone deacetylases, to the promoter. The regulatory function of Myc on NDRG2 gene expression implicated the role of the Ndrg2 in regulating cell differentiation.

Animals↗

PubMed2006

Expression of discoidin domain receptor 2 (DDR2) extracellular domain in pichia pastoris and functional analysis in synovial fibroblasts and NIT3T3 cells.

Discoidin domain receptor 2 (DDR2) is a kind of protein tyrosine kinases associated with cell proliferation and tumor metastasis, and collagen, identified as a ligand for DDR2, up-regulates matrix metallloproteinase 1 (MMP-1) and MMP-2 expression in cellular matrix. To investigate the roles of DDR2 in destruction of cartilage in rheumatoid arthritis (RA) and tumor metastasis, we tried to express extracellular domain of DDR2 fused with a His tag to increase protein solubility and facilitate purification (without signal peptide and transmembrane domain, designated DR) in Pichia pastoris, purify the expressed protein, and characterize its function, for purpose of future application as a specific DDR2 antagonist. Two clones of relative high expression of His-DR were obtained. After purification by a Ni-NTA (nitric-tri-acetic acid) chromatographic column, soluble fused His-DR over 90% purity were obtained. Competitive binding inhibition assay demonstrated that expressed His-DR could block the binding of DDR2 and natural DDR2 receptors on NIT3T3 and synovial cell surfaces. Results of RT-PCR, Western blotting, and gelatinase zymography showed that His-DR was capable of inhibiting MMP-1 and MMP-2 secretion from NIT3T3 cells and RA synoviocytes stimulated by collagen II. For MMP-1, the inhibitory effect was displayed at the levels of mRNA and protein, whereas for MMP-2 it was demonstrated at the level of protein physiological activity. All these findings suggested that the fused expressed His-DR inhibited the activity of natural DDR2, and relevant MMP-1 and MMP-2 expression in synoviocytes and NIH3T3 cells provoked by collagen II.

Amino Acid Sequence↗

PubMed2006

Evaluation of the stress-inducible production of choline oxidase in transgenic rice as a strategy for producing the stress-protectant glycine betaine.

Glycine betaine (GB) is a compatible solute that is also capable of stabilizing the structure and function of macromolecules. Several GB-producing transgenic rice lines were generated in which the Arthrobacter pascens choline oxidase (COX) gene, fused to a chloroplast targeting sequence (TP) was expressed under the control of an ABA-inducible promoter (SIP; stress-inducible promoter) or a ubiquitin (UBI) gene promoter that is considered to be constitutive. This comparison led to interesting observations that suggest complex regulation with respect to GB synthesis and plant growth response under stress. In spite of the use of the well-studied stress-inducible promoter, the highest level of GB accumulation (up to 2.60 micromol g(-1) DW) in the SIP lines grown under saline conditions was not as high as in the UBI lines (up to 3.12 micromol g(-1) DW). Therefore, the use of an ABA-inducible promoter was not more beneficial for de novo production of GB. Interestingly, saline growth conditions enhanced GB accumulation by up to 89% in the SIP lines, whereas up to 44% increase was seen in a UBI line. In all these cases the GB levels were many-fold below the range reported for plant species that produce GB naturally. In spite of lower GB concentrations, statistically greater levels of stress tolerance were found in SIP lines than in UBI lines, suggesting that the stress protection observed in SIP plants cannot be totally explained by the increase in the GB content.

Abscisic Acid↗

PubMed2006

Integration of double-fluorescence expression vectors into zebrafish genome for the selection of site-directed knockout/knockin.

Production of zebrafish by modifying endogenous growth hormone (GH) gene through homologous recombination is described here. We first constructed the targeting vectors pGHT1.7k and pGHT2.8k, which were used for the knockout/knockin of the endogenous GH gene of zebrafish, and injected these two vectors into the embryos of zebrafish. Overall, the rate of targeted integration with the characteristic of germ line transmission in zebrafish was 1.7 x 10(-6). In one experimental patch, the integrating efficiency of pGHT2.8k was higher than that of pGHT1.7k, but the lethal effect of pGHT2.8k was stronger than that of pGHT1.7k. The clones with the correct integration of target genes were identified by a simple screening procedure based on green fluorescent protein (GFP) and RFP dual selection, which corresponded to homologous recombination and random insertion, respectively. The potential homologous recombination zebrafish was further bred to produce a heterozygous F1 generation, selected based on the presence of GFP. The potential targeted integration of exogenous GH genes into a zebrafish genome at the P0 generation was further verified by polymerase chain reaction and Southern blot analysis. Approximately 2.5% of potential founder knockout and knockin zebrafish had the characteristic of germ line transmission. In this study, we developed an efficient method for producing the targeted gene modification in zebrafish for future studies on genetic modifications and gene functions using this model organism.

Animals↗

PubMed2006

Myxoma virus M11L blocks apoptosis through inhibition of conformational activation of Bax at the mitochondria.

Many viruses inhibit or retard apoptosis, a strategy that subverts one of the most ancient antiviral mechanisms. M11L, a myxoma virus-encoded antiapoptotic protein, has been previously shown to localize to mitochondria and block apoptosis of virus-infected cells (H. Everett, M. Barry, S. F. Lee, X. J. Sun, K. Graham, J. Stone, R. C. Bleackley, and G. McFadden, J. Exp. Med. 191:1487-1498, 2000; H. Everett, M. Barry, X. Sun, S. F. Lee, C. Frantz, L. G. Berthiaume, G. McFadden, and R. C. Bleackley, J. Exp. Med. 196:1127-1139, 2002; and G. Wang, J. W. Barrett, S. H. Nazarian, H. Everett, X. Gao, C. Bleackley, K. Colwill, M. F. Moran, and G. McFadden, J. Virol. 78:7097-7111, 2004). This protection from apoptosis involves constitutive-forming inhibitory complexes with the peripheral benzodiazepine receptor and Bak on the outer mitochondrial membrane. Here, we extend the study to investigate the interference of M11L with Bax activation during the process of apoptosis. Myxoma virus infection triggers an early apoptotic signal that induces rapid Bax translocation from cytoplasm to mitochondria, despite the existence of various viral antiapoptotic proteins. However, in the presence of M11L, the structural activation of Bax at the mitochondrial membrane, which is characterized by the occurrence of a Bax conformational change, is blocked in both M11L-expressing myxoma-infected cells and M11L-transfected cells under apoptotic stimulation. In addition, inducible binding of M11L to the mitochondrially localized Bax is detected in myxoma virus-infected cells and in M11L/Bax-cotransfected cells as measured by immunoprecipitation and tandem affinity purification analysis, respectively. Importantly, this inducible Bax/M11L interaction is independent of Bak, demonstrated by the complete block of Bax-mediated apoptosis in myxoma-infected cells that lack Bak expression. Our findings reveal that myxoma M11L modulates apoptosis by multiple independent strategies which all contribute to the blockade of apoptosis at the mitochondrial checkpoint.

Animals↗

PubMed2006

[Effects of glucose and free fatty acids on apoptosis of human vascular endothelial cells].

This study sought to assess effect of high level of glucose or free fatty acids (FFAs) on apoptosis of vascular endothelial cell, and to examine whether the combined presence of high concentrations of glucose and FFAs may cross-amplify their individual detrimental effect. Cultured endothelial cell sline (ECV304) were incubated with various concentrations of glucose and/or selected FFAs (palmitate and/or oleate) for 24-96 h. Microscopic changes were observed by electron microscopy. DNA fragmentation was visualized by agarose gel electrophoresis. Apoptotic percentage of endothelial cells were determined using flow cytometry. After treatment with 30 mmol/L of glucose, 0.25 of palmitate (PA) and 0.5 mmol/L of oleate (OA) respectively, typical apoptosis morphological changes including condensed chromatin, nuclear fragmentation, reduction in volume and apoptotic bodies were observed under electron microscope, and the agarose gel electrophoresis of DNA from cells treated with high levels of glucose and FFAs revealed "Ladder" pattern. Both high concentrations of glucose and FFAs elicited apoptosis in a time- and dose-dependent manner in endothelial cells, and flow cytometry showed the cells were mainly blocked at G0/G1 phase. The apoptotic percentage of endothelial cells treated with high levels of glucose plus FFAs was significantly higher than that treated with high concentration of glucose or FFAs (PA and/or OA) alone. Both glucose and FFAs at high concentrations can induce apoptosis of endothelial cells. The combined presence of high level of glucose and FFAs may cross-amplify their individual effect.

Apoptosis↗

PubMed2006

[Construction of Tet-on inducible CXCR1 eukaryotic expression plasmid and identification of the expression character in NIH3T3 cells].

AIM: To construct tetracycline (Tet)-controlled inducible vector CXCR1-pTREhyg, and then detect the expression character of CXCR1 under the regulation of Dox in NIH3T3 cells. METHODS: A full length cDNA of human CXCR1 was cloned from sample of fibroblast like synovium (FLS) in rheumatoid arthritis (RA) patient by RT-PCR and then sub-cloned into the pTREhyg plasmid after sequence analysis. CXCR1-pTREhyg and pTet-on was co-transfected with Lipofect2000 to NIH3T3 cells, and the expression of IL-8RA was detected by Western blot after given different concentration of Dox. RESULTS: Western blot showed that CXCR1 could be induced by Dox in NIH3T3 cells, and the phosphorylated Erk-1/2 level was significantly increased after IL-8 stimulation. CONCLUSION: Tet inducible recombinant vector of CXCR1-pTREhyg was successfully constructed, and it could be expressed in NIH3T3 cells. The stimulation of IL-8 obviously changed the activity of Erk-1/2 in the transfected NIH3T3 cells. This work has laid foundations for further study on the relationship between CXCR1 and RA disease.

Animals↗

PubMed2006

[Expression, purification and identification of mouse granulocyte-macrophage colony-stimulating factor].

OBJECTIVE: To construct mouse granulocyte-macrophage colony-stimulating factor (mGM-CSF) expression vector and express, purify and refold mGM-CSF protein. METHOD: Based on previously constructed fusion protein hIL-2/mGM-CSF expression vector, pET-11c/mGM-CSF expression vector was constructed routinely and transformed into BL21 (DE3). The inclusion body protein was washed with our patented method and refolded with renaturation buffer containing low-concentration guanidinium chloride (Gu.Cl). The refolded protein was purified with affinity chromatography. RESULTS: pET-11c/mGM-CSF vector was constructed successfully. The host bacteria was cultured in TH broth and induced with 0.1 mmol/L IPTG at 32 degrees C, which resulted in the expression level of 60.6%. The best refolding effect was achieved with the renaturation media containing glutathione and 1.5 mol/L Gu.HCl. After purification with affinity chromatography, the purity of the target mGM-CSF protein reached 95% with activity of 5x10(6) U/mg. CONCLUSION: Engineered bacteria BL21/pET- 11c/mGM-CSF with efficient mGM-CSF expression and laboratory scale renaturation and purification of mGM-CSF have been established, which facilitates further researches into the anti-tumor function of the dendritic cells and GM-CSF in vivo.

Animals↗

PubMed2005

Novel simian immunodeficiency virus CTL epitopes restricted by MHC class I molecule Mamu-B*01 are highly conserved for long term in DNA/MVA-vaccinated, SHIV-challenged rhesus macaques.

Simian immunodeficiency virus (SIV) infection of rhesus macaques provides an excellent model for investigating the basis of protective immunity against human immunodeficiency virus (HIV). One limitation of this model, however, has been the availability of a small number of known MHC class I-restricted CTL epitopes for investigating virus-specific immune responses. We assessed CTL responses against SIV Gag in a cohort of DNA/modified vaccinia virus Ankara (MVA)-vaccinated/simian-human immunodeficiency virus (SHIV)-challenged rhesus macaques. Here, we report the identification of five novel SIV CTL epitopes in Gag for the first time (Gag(39-46) NELDRFGL, Gag(169-177) EVVPGFQAL, Gag(198-206) AAMQIIRDI, Gag(257-265) IPVGNIYRR and Gag(296-305) SYVDRFYKSL) that are restricted by the common MHC class I molecule Mamu-B*01. CTL responses to these epitopes were readily detected in cryopreserved PBMC in multiple animals up to 62 weeks post-infection, both by IFN-gamma enzyme-linked immunospot assay and intracellular IFN-gamma staining. Importantly, viral sequencing results revealed that these epitopes are highly conserved in the SIV-challenged macaques over a long period of time, indicating functional constraints in these regions. Moreover, the presence of CTL responses targeting these epitopes has been confirmed in two independent cohorts of rhesus macaques that have been challenged by SHIV or SIV. Our findings provide valuable candidates for poly-epitope vaccines and for long-term quantitative monitoring of epitope-specific CD8(+) responses in the context of this common Mamu class I allele. It may thus help increase the supply of rhesus macaques in which epitope-specific immunity can be studied in the context of SIV vaccine design.

Animals↗

PubMed2005

Dietary exposure to heterocyclic amines in a Chinese population.

Heterocyclic aromatic amines (HAAs) formed in meat during high-temperature cooking have been associated with risk of colorectal and breast cancer. Incidence of these cancers is increasing in Singapore, a country with 77% ethnic Chinese. The purpose of this study was to estimate HAA levels in the Chinese diet and individual levels of exposure to these compounds because little is known. Twenty-five samples (each pooled from three sources) of meat and fish, cooked as commonly consumed, were analyzed by high-performance liquid chromatography for concentrations (ng/g) of 2-amino-3-methylimidazo[4,5-f]quinoline, 2-amino-3, 4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8- dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3, 4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx), 2- amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline, 2-amino -1,6-dimethylfuro[3,2-e]imidazo[4,5-b]pyridine, and 2- amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Dietary meat consumption data (g/day), including meat type and cooking method, were gathered from food-frequency questionnaires completed by 497 randomly sampled Chinese men and women aged 20-59 yr. PhIP, MeIQx, and 4,8-DiMeIQx were the most abundant HAAs detected. Total HAA concentrations ranged from <0.10 to 6.77 ng/g, of which Chinese-style roasted pork had the highest levels. The estimated mean daily exposure to HAA was 49.95 ng/day (P10 14.0 ng/day, P90 95.8 ng/day); this was 50% higher among younger (20-39 yr) compared with older individuals. Seven specific meat-cooking method combinations contributed 90.1% of this intake, namely, pan-fried fish, pork, and chicken, deep-fried chicken as well as fish, roasted/barbecued pork, and grilled minced beef.

Adult↗

PubMed2005

[Survey on the contamination of microcystin-LR in water supply of Shanghai city].

OBJECTIVE: To study the pollution level of microcystin-LR in water supply of Shanghai city and the removal efficacy for microcystin-LR through routine water treatment technique. METHODS: High performance liquid chromatogram (HPLC) was applied to determine the concentration of microcystin-LR in source water, water samples after various water treatment procedures and tap water. RESULTS: The concentration of microcystin-LR varied with sampling seasons and sites and reached peak during summer and fall. The maximum of microcystin-LR was 2.38 microg/L in source water. Coagulation plus chlorine disinfection were found to be effective for the removal of microcystin-LR, while the remove rate through filtration was not significant. And it could also be detected in tap water as high as 1.27 microg/L. CONCLUSION: The source waters of Shanghai city were polluted by cyanobacteria toxins represented by microcystin-LR. The source water in suburb was more polluted. Routine water treatment techniques can not remove the toxins effectively.

China↗

PubMed2005

Highly effective expression of glutamine synthetase genes GS1 and GS2 in transgenic rice plants increases nitrogen-deficiency tolerance.

Glutamine synthetase (GS, EC6.3.1.2) is a key enzyme in ammonia assimilation both in plants and in Gram-negative microorganisms. It plays an important role in efficient use of nitrogen sources and nitrogen metabolism in organisms. Two groups of GS isoenzymes, plastidic (GS2) and cytosolic (GS1), have been identified in higher plants. A plant constitutive expression vector p2GS harboring GS1 and GS2 under the control of rice actin 1 (Act1) and maize ubiquitin (Ubi) promoters was constructed for the first time in a single plasmid, and 3 rounds of ligation and transformation were performed. There has been no report about studies on rice transformation with the two GS enzymes (GS1 and GS2). The p2GS thus constructed was introduced into rice var. Zhonghua 10 by Agrobacterium-mediated transfer method, and transgenic plants with resistance to hygromycin (Hyg) were obtained. Results of PCR and Southern blot analysis showed that the foreign genes have been integrated into the rice genome. The transcription of GS1-GS2 genes in the transformants was also confirmed by Northern blot analysis. The transgenic rice plants thus obtained can grow well in an MS medium in which the nitrogen source was replaced by (NH(4))(2)SO(4) 0.7 mmol/L, and fresh weight of the transformants was significantly higher than the control rice plants. The result suggests that expression of p2GS makes the transgenic rice plants tolerant to nitrogen-deficiency.

Adaptation, Physiological↗

PubMed2005

[Study on DNA damage induced by microcystin-LR].

OBJECTIVE: To investigate whether microcystin-LR (MC-LR) at doses which were not cytotoxic can induce DNA damage and compare its effect on HL-7702 and KB cell lines. METHODS: Cytotoxin and DNA damage were detected by MTT and comet assay, respectively. RESULTS: As doses ranged from 10 to 100 micro/L, MC-LR showed no significant impact on viability of these two cell lines. However, DNA damage induced by MC-LR occurred at the dose of 30 microg/L in HL-7702 cell and significantly increased with dose. MC-LR did not induce DNA damage in KB cell. CONCLUSION: MC-LR has potential genotoxicity, DNA damage induced by MC-LR is more significant in hepatocyte with bile acid transportation system than other cell lines.

Cell Line↗

PubMed2004

Monomeric C18 chromatographic method for the liquid chromatographic determination of lipophilic antioxidants in plants.

Reversed-phase liquid chromatography was used to determine lipophilic antioxidants in plants using two monomeric C18 columns operated at 30 degrees C and 4 degrees C, with a column-switching technique and acetonitrile-methanol gradient elution. The chromatograms were extracted at different wavelengths using a UV diode array detector (DAD). A wide range of plant antioxidants, including nine carotenoids (neoxanthin, violaxanthin, lutein, zeaxanthin, beta-cryptoxanthin, lycopene, canthaxanthin, alpha-carotene and beta-carotene) together with all-trans-retinol, capsaicin, dihydrocapsaicin, chlorophyll a, and chlorophyll b can be separated within 50 min. Fluorometric detection was applied to quantify trace amounts of six vitamin E analogues (alpha-, delta- and gamma-tocopherols and tocotrienols). The detection limits were 0.2-0.4 microg/g for various xanthophylls and 0.04-0.10 microg/g for vitamin E analogues.

Antioxidants↗

PubMed2004

Sequence of beta(2)-microglobulin from rhesus macaque ( Macaca mulatta) includes an allelic variation in the 3'-untranslated region.

The rhesus macaque ( Macaca mulatta) has become a popular animal model for several human infectious diseases, such as HIV (modeled by SIV infection), hepatitis, and malaria. Investigation of T-cell responses in experimental infectious diseases in rhesus macaques has benefited from an expanding understanding of the diversity of macaque MHC class I heavy chains and the restriction of antigen presentation by macaque class I molecules. Here we add to this understanding with the first nucleotide sequences of M. mulatta beta(2)-microglobulin (beta(2)m) mRNA, including a portion of the 3'-untranslated region (3'UTR). In pairwise comparison, the beta(2)m protein of M. mulatta differs from human and chimpanzee beta(2)m by nine amino-acid substitutions (92% identity), and from Macaca fascicularis by one amino-acid difference in the signal peptide region (99% identity). Allelic variations were identified at one site in the 3'UTR. A structural analysis of human or chimpanzee beta(2)m and M. mulatta beta(2)m suggests that the differences cluster in three solvent-exposed clusters and do not involve contacts with the class I heavy chain. We predict that human and macaque beta(2)m should bind interchangeably with the class I heavy chains of the other species, and show that four M. mulatta class I alleles form cell surface complexes with human beta(2)m. Further, we predict that W6/32 (a monoclonal antibody that recognizes a combined epitope of some class I heavy chains and beta(2)m with a subtle species dependence) should bind similarly human or macaque class I molecules that are bound with beta(2)m of either species, supported by evidence of recognition of both heterologous and homologous complexes of macaque class I heavy chains. Our findings contribute to the growing understanding of rhesus macaque histocompatibility antigens and antigen presentation, and to the phylogeny of beta(2)m in primates.

3' Untranslated Regions↗

PubMed2002

Tripeptide interference with human immunodeficiency virus type 1 morphogenesis.

Capsid assembly during virus replication is a potential target for antiviral therapy. The Gag polyprotein is the main structural component of retroviral particles, and in human immunodeficiency virus type 1 (HIV-1), it contains the sequences for the matrix, capsid, nucleocapsid, and several small polypeptides. Here, we report that at a concentration of 100 micro M, 7 of 83 tripeptide amides from the carboxyl-terminal sequence of the HIV-1 capsid protein p24 suppressed HIV-1 replication (>80%). The three most potent tripeptides, glycyl-prolyl-glycine-amide (GPG-NH(2)), alanyl-leucyl-glycine-amide (ALG-NH(2)), and arginyl-glutaminyl-glycine-amide (RQG-NH(2)), were found to interact with p24. With electron microscopy, disarranged core structures of HIV-1 progeny were extensively observed when the cells were treated with GPG-NH(2) and ALG-NH(2). Furthermore, nodular structures of approximately the same size as the broad end of HIV-1 conical capsids were observed at the plasma membranes of treated cells only, possibly indicating an arrest of the budding process. Corresponding tripeptides with nonamidated carboxyl termini were not biologically active and did not interact with p24.

Capsid Proteins↗

PubMed2002

Preparation and identification of monoclonal antibodies against human brain-derived neurotrophic factor.

OBJECTIVE: To prepare monoclonal antibodies (mAbs) against human brain-derived neurotrophic factor (BDNF). METHODS: BALB/C mice were immunized with purified BDNF protein in conjunction with acid-treated Salmonella (antigen:thallus=1:5), and mAbs were subsequently derived by hybridoma technique. RESULTS: Three hybridoma cell lines secreting anti-BDNF mAbs were obtained, designated as B1, B2 and 4D1 respectively and all categorized into IgG1 subtype. The titers of the mAbs in the ascitic fluid of the rats ranged from 1x10(6) to 1x10(5), and their relative affinities were B2>B1>4D1. CONCLUSION: mAbs against BDNF are successfully prepared, which can be instrumental for further study of the expression and distribution of BDNF in vivo, and the detection of BDNF produced by genetic engineering.

Animals↗