Z Chen

Zhejiang Medical University, Hang-hsien, Zhejiang Sheng, China

Are you Z Chen?

Claim your profile

Publications (7)3.16 Total impact

  • R H Dennin · J Wo · Z Chen · Ch Roos
    [Show abstract] [Hide abstract]
    ABSTRACT: The DNA from PBMCs of both hepatitis C virus (HCV)-positive patients and healthy HCV-negative human individuals tested thus far contains essential parts--up to 272/341 nucleotides--of the HCV 5'-non-coding region (5'-NCR). These findings bring up the question of the possible evolutionary background of these sequences. Therefore, using the same methodology, we looked for the same sequences in animals closely related to man, i.e., in nonhuman primates (two chimpanzees, one orang-utan, one Debrazza monkey, two New World monkey species and a prosimian). The DNA from PBMCs of the studied animals belonging to nonhuman primates contains essential parts--up to 272/341 nucleotides--of the HCV 5'-non-coding region (5'-NCR). A common sequence of 82 nucleotides is contained in the DNA of all the tested animals but only the chimpanzee's DNA harbors the same, longer sequence region of 272/341 nucleotides of the 5'-NCR found in human DNA. The results may provide a clue as to the possible origin of parts of the IRES containing sequence area of the HCV.
    No preview · Article · Jan 2001 · Zeitschrift für Gastroenterologie
  • J Dou · KZ Liu · Z Chen · J Wo · NX He · Y Liu · MT Zhang · XZ Wang · CH Xu
    [Show abstract] [Hide abstract]
    ABSTRACT: To explore the possibility and the efficacy of immune responses in mice inoculated with recombinant plasmid pCD-HCV1 and to lay a foundation for HCV nucleic acid vaccine development in the future. The gene fragment coding C and E regions of HCV-II (type I b) was inserted into pCD-SR alpha 1 expression vector and formed pCD-HCV1 and then was injected into quadriceps muscles of Balb/c mouse. Serum anti-HCV level of mice was tested by ELISA (A value). Spleen cells proliferation responses to HCV antigens were detected by 3H-TdR incorporation (cpm). Balb/c mice immunized with recombinant plasmid pCD-HCV1 three or four times can generate specific antibody responses to HCV antigens and the antibody levels gradually ascend to the plateaus and did not have the trend of descending in 18 weeks detected. The serum antibodies in mice immunized by recombinant plasmid pCD-HCV1 were 100 percent positive when the serum were diluted 40 times and the positive rate of antibody still were 16.6 percent positive when the serum were diluted 320 times. Balb/c mice immunized with recombinant plasmid pCD-HCV1 (100 micrograms, 50 micrograms 10 micrograms/mouse three times respectively) can elicit antibody responses to HCV antigens and the antibody levels of three groups were 0.70 +/- 0.07, 0.33 +/- 0.04 and 0.11 +/- 0.09 respectively. Spleen cells of Blab/c mice injected with pCD-HCV1 three times were induced to produce proliferation responses to HCVc + e specific antigens. These results demonstrated that constructs expressioning HCV core and envelope proteins can generate anti-HCVc + e specific antibody responses and lymphoproliferation responses in mice, which suggested it to be possible to elicit immune responses to viral epitopes from HCV via DNA immunization with HCV-DNA recombinant and to warrant further investigation as a potential vaccine against HCV infections.
    No preview · Article · Dec 1999 · Chinese medical journal
  • Z Chen · Y Liu · M Chen
    [Show abstract] [Hide abstract]
    ABSTRACT: To establish an MT-2 cell model infected by HCV in vitro. Human T-lymphocyte cell line MT-2 was infected with HCV-RNA positive serum and detected for HCV RNA by RT-PCR 1, 4, 7, 10, 14, 18, 21, 24, 28, 31, 35 and 39 days after the infection. PCR products were determined by southern blot. MT-2 cell infected with HCV-RNA negative serum was used as control. HCV-RNA began to turn positive at 7 days postinoculate (p.i.) till at least 28 days(p.i.). Intracellular negative-stranded HCV-RNA was detected from 10 to 18 days (p.i.). No HCV RNA was detected in the control group. HCV may replicate and express in MT-2 cell for a short period.
    No preview · Article · Oct 1999 · Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology
  • J Dou · K Liu · Z Chen · J Wo · Y Liu · C Xu · M Chen · J Jin · N He
    [Show abstract] [Hide abstract]
    ABSTRACT: To inquire into the immune responses to expression protein in mice immunized with genetic vaccine of hepatitis C virus (HCV) and lay a foundation for HCV genetic vaccine development in future. The gene fragments coding C and most E regions of HCV-II type were inserted into pCD-SRalpha(1) of eukaryotic expression vector and formed genetic vaccine constructs of pCD-HCV(1) and then was injected into the quadriceps muscles of Balb/c mice. The serum anti-HCV level of mice was tested by ELISA and peripheral blood mononuclear cell (PBMC) proliferative responses to HCV antigens were detected by (3)H-TdR incorporation method (cpm). The serum antibody level reached to 0.71 +/- 0.08 - 0.77 +/- 0.06 (A value, the same below) after genetic vaccine pCD-HCV(1) (100 microg/mouse) were inoculated into the mice (n = 12) three or four times while blank vector pCD-SRalpha(1) could not induce the mice (n = 8) to generate antibody response in same way. After the antibody levels in mice (n = 8) immunized by pCD-HCV(1) had ascended to peak value (0.71), there was no trend of descending during the following 18 weeks of detection (0.68 +/- 0.06 - 0.75 +/- 0.07). Specific fragment of HCV cDNA identified by polymerase chain reaction (PCR) from DNA extracted from the muscles of the mice after pCD-HCV(1) had been inoculated three months. PBMC proliferative responses to HCV synthetic peptides CP(9) and gene recombinant antigens C, E(1) in the mice immunized with pCD-HCV(1) were detected and its stimulation indexes (SI) were 4.07 +/- 1.58, 3.88 +/- 0.70 and 3.69 +/- 1.13 respectively and there was a significant difference (P < 0.001) as compared with that of PBMC in mice immunized with pCD-SRalpha(1). These investigations demonstrated that genetic vaccine constructs made of HCV structural region can induce Balb/c mice to generate antibody and PBMC proliferative responses to HCV antigens via DNA immunization.
    No preview · Article · Jun 1999 · Zhonghua nei ke za zhi [Chinese journal of internal medicine]
  • F Chen · W Cai · Z Chen · R Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: To explore the changes in TGF-beta 1 mRNA in patients with schistosomal liver fibrosis. Reverse-transcription polymerase chain reaction and dot blot analysis were used to determine the level of TGF-beta 1 mRNA in PBMC. The serum levels of hyaluronic acid, type IV collagen, laminine and procollagen III peptide were also measured simultaneously. The mean level (m +/- s) of PBMC TGF-beta 1 mRNA was significantly higher in late-stage schistosomiasis group (LSS) (1.26 +/- 0.14), liver cirrhosis group (LC) (2.05 +/- 0.81) and hepatocellular carcinoma group (HCC) than that in control group (0.62 +/- 0.40) (P < 0.05). PBMC TGF-beta 1 mRNA level was higher in LC and HCC than that in LSS (P < 0.05). No significant difference was found in TGF-beta 1 mRNA between PBMC and liver tissue in patients with HCC. All patients with increased fibrogenic activity (i.e., abnormal levels of serum HA, Col-IV and LN) had increased levels of TGF-beta 1 mRNA. The level of TGF-beta 1 mRNA is correlated with the fibrotic activity of liver, the increasement of TGF-beta 1 mRNA in schistosomiasis patients after praziquantel treatment might induce liver fibrosis.
    No preview · Article · Jan 1999 · Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases
  • R H Dennin · Z Chen · J Wo
    [Show abstract] [Hide abstract]
    ABSTRACT: The sequence 'GOR47-1' is a consistent part of human DNA; the expressed polypeptide of it 'GOR' is accepted to be an autoantigen, and the anti-GOR an autoantibody. However, GOR47-1 was originally isolated through a cDNA clone from blood of a chimpanzee. This animal belonged to a series of chimpanzees, in which human plasma of a patient with non-A, non-B hepatitis had been passaged. To date, nothing is known how it is that this 'sequence GOR47-1' without recognizable self-replicating properties and allocated to the human genome could be isolated from a chimpanzee plasma. The aim of this study was to detect by polymerase chain reaction GOR47-1 sequences in healthy, anti-HCV-negative humans, HCV-positive patients, chimpanzee, snake, and in maize and tobacco plants. The GOR47-1 sequence is present not only in human DNA but also with a high degree of homology in chimpanzee DNA. Essential parts of this sequence are also present in DNA of a snake and the two plants listed above. Our findings reveal that the GOR47-1 sequence isolated from a chimpanzee was probably of the chimpanzee origin. This fact has not yet been considered up until now, when discussing the role of GOR/anti-GOR in humans particularly suffering from chronic hepatitis C.
    No preview · Article · Nov 1998 · Zeitschrift für Gastroenterologie
  • F Chen · W Cai · Z Chen · R Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: To establish a method to measure the TGF-beta 1 mRNA level for studying the mechanism of fibrogenesis caused by schistosomiasis japonica. Reverse-transcription polymerase chain reaction and dot blot analysis were used. A plasmid of TGF-beta 1 was constructed for standardization, and beta-actin was used as control. Eight different concentrations of the plasmid and 11 double-tube of TGF-beta 1 mRNA in the peripheral blood mononuclear cell (PBMC) of different persons were measured. Quantitative results of 8 different dilutions of TGF-beta 1 plasmid had positive with the logarithm of the original concentration. The results of the 11 double-tube were 1.71 +/- 0.90 and 1.54 +/- 0.88. The duplicability and stability of the method showed it can be used to analyse the TGF-beta 1 mRNA level of the peripheral blood mononuclear cells.
    No preview · Article · Feb 1998 · Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases