Table of Content

30 April 2006, Volume 24 Issue 2

Previous Issue    Next Issue

论著

Anti-Schistosomiasis Effect Induced by Full Length DNA Vaccine Coding Paramyosin of Schistosoma japonicum in C57BL/6 Mice

CHENJia-xu;LIUShu-xian;CAOJian-ping;SONGGuang-cheng;XUYu-xin

2006, 24(2):  1-85. 

Asbtract ( )   PDF (272KB) ( )  

Related Articles | Metrics

Objective To observe the anti-schistosomiasis effect in mice immunized with Sjc97 DNA vaccine.Methods C57BL/6 mice were vaccinated intramuscularly with the Sjc97 DNA twice at an interval of 3 weeks， and challenged with 30±2 cercariae of Schistosoma japonicum three weeks after immunization. Mice in blank plasmid vector control and infection control groups were also infected with same number of cercariae. The mice were sacrificed 7 weeks after challenge infection. The size of single egg granulomas in livers was measured with micrometer. The level of hyaluronic acid （HA） and laminin （LN） in sera of the mice was determined by ELISA. PCR-ELISA was used to examine the expression of TGF-β1 mRNA in liver. Results The mean hepatic egg granuloma diameters of the three groups， the Sjc97 DNA， blank plasmid vector and infection control， were 183.75±42.36 microns， 303.12±37.36 microns and 304.38±53.23 microns， respectively. The hepatic granuloma was significantly smaller in the Sjc97 DNA group than that in control. The level of HA and LN in sera of Sjc97 DNA vaccinated mice was markedly lower than those in the two control groups（P<0.01）. The amount of TGF-β1 mRNA isolated from the livers of mice in Sjc97 DNA group decreased significantly. Conclusion The results showed that Sjc97 DNA vaccine may act as an effective inhibitor against formation of egg granuloma and reduce immunopathological damage caused by Schistosoma japonicum in the host.

Identification of the SjARG Novel Gene and Study on Its Protective Potential as a Vaccine

LIZi;YUXin-bing;WUZhong-dao;HUXu-chu

2006, 24(2):  2-91. 

Asbtract ( )   PDF (348KB) ( )  

Related Articles | Metrics

Objective To recognize and identify the arginase （ARG） gene of Schistosoma japonicum（Sj）, and to study its protection potential as a vaccine. Methods The 5′-end of the ARG gene from the Sj cercariae cDNA library was amplified by nested-PCR and the sequence was identified by bioinformatics. The complete coding sequence（CDS） was cloned into pET30a（+） vector, and a recombinant SjARG protein （rSjARG） was expressed， purified and used to raise antibodies. ARG′s activity
as an enzyme was tested by ornithine-ninhydrin reaction. Western blotting was used to compare the immunologic characteristics of rSjARG with that of the native one in Sj adult worm. Indirect immunofluorescence assay was used to immunolocalize it. For evaluating the protection potential of rSjARG, mice were immunized by the recombinant protein and challenged by cercariae of S. japonicum. Results The CDS length of the SjARG novel gene was identified as 1095bp. rSjARG showed enzyme activity and the same immunologic characteristics with the native arginase in adult worm. SjARG located in the genital organ and gut of both sexes. The worm reduction rate and egg reduction rate in rSjARG group were 55.8% and 48.8% respectively, higher than that of the rSj26GST group （28.6% and 6.89% respectively）. Conclusion SjARG gene was identified, which shows a higher protection than the Sj26GST.

Study on PCR Method for Detecting the AsymptomaticInfection of Leishmania infantum

GAOChun-hua;WANGJun-yun;YANGYue-tao;BAOYi-fang

2006, 24(2):  3-96. 

Asbtract ( )   PDF (381KB) ( )  

Related Articles | Metrics

Objective To establish PCR method for the detection of the asymptomatic infection of Leishmania infantum. Methods Six primer pairs were selected for detecting Chinese strain of L.infantum by optimizing conditions which affect amplification. Their sensitivity and specificity were compared by using DNAs extracted from human blood seeded with cultured L.infantum promastigotes （MHOM/CN/86/GS） as template. Blood samples of the inhabitants without symptoms of visceral leishmaniasis in the endemic area were analyzed with two selected primer pairs with good sensitivity and specificity. Results The specificity of all six primer pairs reached 100%， and the sensitivity varied among the primer pairs. The primer pairs RV1-RV2（0.1 parasite/ml blood） and K13A-K13B（1 parasite/ml blood） were most sensitive. Leishmania DNA was detected in 33% （33/100） and 30% （30/100） human blood samples by RV1-RV2 and K13A-K13B primer pairs respectively. Conclusion This study suggests that RV1-RV2 and K13A-K13B primer pairs are suitable in detecting the asymptomatic infection of L.infantum， and the prevalence of the asymptomatic infection is high in human population in the endemic area.

Construction and Expression of Schistosoma japonicum Bivalent DNAVaccines and Their Efficiencies of Protective Immunity

HUYuan;SHIYou-en;ZHUXiao-hua;NINGChang-xiu;ZHUHong-gang

2006, 24(2):  4-101. 

Asbtract ( )   PDF (307KB) ( )  

Related Articles | Metrics

Objective To study the efficiency of protective immunity afforded by the constructed bivalent DNA vaccines of Schistosoma japonicum. Methods The plasmids pVIVO2-mcs-SjFABP-Sj23 and pVIVO2-mcs-Sj23-SjFABP， co-expressed bivalent DNA vaccines， were constructed and identified. The presence of bivalent DNA vaccine in the mouse muscle cells was also tested by indirect immunofluorescent antibody tests （IFAT）. 70 BALB/c mice were randomly divided into seven groups to be injected with normal saline, pVIVO2-mcs, pVIVO2-mcs-Sj23, pVIVO2-mcs-SjFABP, pVIVO2?-mcs-Sj23-SjFABP, pVIVO2-mcs-SjFABP-Sj23 plasmid DNA, and a mixture of pVIVO2-mcs-Sj23-SjFABP plasmid DNA and amylose adjuvant, respectively. At day 45 after challenge the mice were sacrificed. The number of adult worms and hepatic eggs were counted. Result Successful construction of co-expressed bivalent DNA vaccines were identified by restriction analysis and sequencing. It was confirmed by IFAT that the bivalent DNA vaccine was expressed in the plasma and on the surface of muscle cells from mouse. The worm reduction rate was 41.20%-53.85% and the egg reduction rate was 47.02%-53.83% bivalent DNA groups. Furthermore， the worm and egg reduction rates in pVIVO2-mcs-Sj23-SjFABP plasmid DNA and amylose adjuvant group were 68.89% and 84.04% respectively， significantly higher than single antigenic DNA vaccine and bivalent DNA vaccine （P<0.05）. Conclusion The co-expressed bivalent DNA vaccines of Schistosoma japonicum can induce immune protection in mice. The protective immunity of amylose adjuvant group is higher than that of the univalent DNA and bivalent vaccines.

Establishment of In vitro Microtest for Determining Sensitivity ofPlasmodium falciparum to Pyronaridine

LIUDe-quan;FENGXiao-ping;LIURui-jun;ZHANGChun-yong

2006, 24(2):  5-105. 

Asbtract ( )   PDF (240KB) ( )  

Related Articles | Metrics

Objective To establish an in vitro microtest for determining the sensitivity of Plasmodium falciparum to pyronaridine Methods Pyronaridine-coated plate and culture medium which is easy to use in the field were prepared. P.falciparum parasites from in vitro continuous passage culture（FCC1/HN） were used for experimental tests in the laboratory. When they were proved stable and reliable through repeated determinations， field trials were made in Hainan and Yunnan Provinces during the malaria transmission season with blood samples from clinical falciparum malaria cases. A 4-week in vivo test was carried out as a control. Results The pyronaridine-coated plate and culture medium were proved to be stable. The effective period of pyronaridine-coated plate， the ampule sealed liquid culture medium and the bottled lyophilized culture medium， all stored at 4 ℃ was 6 months， 2 months and 2 years respectively. Through several years field determinations， the baseline data of pyronaridine-sensitivity of P.falciparum in the country were collected and the sensitivity of P.falciparum to pyronaridine was also revealed to have decreased gradually. The mean drug concentration for in vitro complete inhibition of schizont formation raised by 2-4 times although the clinical therapeutic efficacy of pyronaridine was still satisfactory at the present time. Conclusion The developed in vitro microtest can be used for determination of the sensitivity of P.falciparum to pyronaridine， and it is more convenient and sensitive than the 4-week in vivo method.

Immunoscreening of Schistosomulum cDNA Library of Schistosomajaponicum and Preliminary Identification of Membrane-AssociatedProtein Abundant in Tegument

ZHUShao-chun;ZHAOZhi-rong;LEILi;ZHANGLin-jie;SHENJi-jia;

2006, 24(2):  6-110. 

Asbtract ( )   PDF (383KB) ( )  

Related Articles | Metrics

Objective To obtain genes encoding the novel molecules for diagnosis of schistosomiasis. Methods Juvenile S. japonicum cDNA library was immunoscreened to obtain positive clones. By DNA sequencing and sequence analysis， the target gene was amplified by PCR and subcloned into prokaryotic plasmid pET28a. The recombinant plasmid was transformed into E. coli BL21 followed by expression of the protein induced by IPTG. The protein was identified by Western blotting. Results 34 positive clones were obtained， 24 of which were chosen to be sequenced， 13 of which were Sj22600 gene. The protein were recognized with sera of infected rabbits and patients with acute and chronic schistosomiasis by Western blotting. Conclusion The gene coding for Sj22600 membrane protein was screened with high frequency in the cDNA library. The E. coli BL21 transformed with the recombinant plasmid can express the fusion protein，which shows immunoactivity.

A Comparative Study on Isoenzymes of Sarcocystis spp. fromCattle and Water Buffaloes

LIANGYi-long;XIEYong-fang;ZUOYang-xian;TANDe-yong;SHUKun-xian;CHENXin-wen

2006, 24(2):  7-113. 

Asbtract ( )   PDF (201KB) ( )  

Related Articles | Metrics

Objective To analyze the zymogram of peroxidase （PER） and phosphoglucose isomerase （PGI） of three species of Sarcocystis. Methods The collected parasites were homogenized and fragmented by ultrasonication. After centrifugation, the supernatants were analyzed by isoelectric focusing electrophoresis. Results The isolates of S. cruzi from infected water buffalo and cattle all showed identical enzyme profiles, 7 bands of PER at pH4.44~6.98 and 6 bands of PGI at pH 4.66~6.53；and same with the isolates of S. hirsuta. 5 bands of PER at pH 4.97~7.15 and 4 bands of PGI at pH 4.70~6.51. The zymograms among S. cruzi, S. hirsuta and S. fusiformis were different considerably. Conclusion The data support the hypothesis that both water buffalo and cattle are the natural intermediate hosts of S. cruzi and S. hirsuta at the gene level. S. cruzi, S. hirsuta and S. fusiformis are different species.

Effect of Chronic Toxoplasma Infection on the Spatial Learningand Memory Capability in Mice

WANGHui-ling;BAOAn-yu;WANGGao-hua;WANGGao-hua;LIUZhong-chun;DONGHui-fen;GUOYi

2006, 24(2):  8-118. 

Asbtract ( )   PDF (456KB) ( )  

Related Articles | Metrics

Objective To investigate the effect of chronic infection of Toxoplasma gondii on the spatial learning and memory capability in mice. Methods Toxoplasma tachyzoites （RH strain） were reanimated at 37 ℃ after 15 days′ storage at -20 ℃， and injected intraperitoneally to mice of the experimental group each with 7.7×10⁵. Normal saline was given to the control group， 0.5 ml per mouse. Two months later， all mice were tested in the Morris Water Maze. Smears of the mice brain homogenate and pathological sections were examined. Results ① The density of cysts in the brain homogenate was 15/HP， and there was no evident pathological change in the hippocampus and adjacent areas of mice in the brain in the experimental mice. ② Latency to platform， cumulative distance to the platform， total distance traveled in both experimental and control groups decreased significantly with the increase of training days （P<0.01）. The latency and cumulative distance in experimental group were significantly longer than that of the control group （P<0.01）. ③ The searching strategy of mice in the experimental group was significantly different from that of the control group. Conclusion Toxoplasma tachyzoites can induce chronic infection in mice and the infection can damage at some extent the spatial learning and memory capability of mice.

实验报道

Sequence Analysis of ITS2 and CO1 Genes of Paragonimus harinasutai

QIANBao-zhen;H.Sugiyama;J.Waikagul;ZHUZhi-hang

2006, 24(2):  9-121. 

Asbtract ( )   PDF (193KB) ( )  

Related Articles | Metrics

Objective To identify Paragonimus harinasutai from Ninghai， Zhejiang Province， China. Methods Meta-cercariae were collected from the crabs Sinopotamon chekiangenes in Xixi village of Ninghai County for ITS2 sequence analysis， CO1 sequence analysis and endonuclease BsaHI and StuI analysis by PCR-RFLP. Results The fingerprintings of PCR-RFLP were virtually same to the isolate from Thailand （Nakorn-nayok）. The ITS2 sequence with 366 bp and CO1 sequence with 390 bp of the metacercariae collected from Ninghai revealed a nucleotide identity 95.6% and 89.5% respectively to the Thai isolate. Conclusion The study confirmed that Paragonimus harinasutai is present in Ninghai， China， with certain variation on molecular biology in comparison to the Thai isolate.

Changes of Peripheral Blood T Lymphocytes， IFN-γ， TNF-α andIL-4 in Rats Infected by Toxoplasma gondii

WANGChun-li;ZHOUYong-hua;LIUJian-hu

2006, 24(2):  10-124. 

Asbtract ( )   PDF (211KB) ( )  

Related Articles | Metrics

Objective To observe the changes of peripheral blood T lymphocytes， IFN-γ, TNF-α and IL-4 in rats infected by T. gondii. Methods 48 Sprague-Dawley（SD） rats were intra-abdominally injected with 2×10⁵/L of cellulose purified living tachyzoites in 2 ml and randomly divided into 8 groups. Six rat was intra-abdominally injected 2 ml of saline as control and 4 rats were remained as normal control. Peripheral blood was collected and the level of IFN-γ, TNF?-α, IL-4 was analyzed by ELISA on day 1, 3, 7, 14, 28, 35, 42, 60. Results Level of IFN-γ （6.73 pg/ml） and IL-4 （6.91 pg/ml） increased in experimental rats on day 7 （P<0.05） and maintained. Level of TNF-α （14.37 pg/ml） increased in experimental rats on day 28 （P<0.05）， and that of CD8+ T lymphocytes （14.22%） was significantly lower than that in control （23.08%） （P<0.05） and recovered on day 28. No considerable change was observed on the level of CD4+ T lymphocytes. Conclusion The level of CD8+ T lymphocytes, IFN-γ, TNF-α and IL-4 in the rat can be affected by the infection of T. gondii and the level of CD4+ T lymphocytes shows no change.

Effect of rmu-IFN-γ on the Splenic T Cell Subsets and NK Cellsof Pregnant Mice Infected with Toxoplasma gondii

LUOFang-jun

2006, 24(2):  11-128. 

Asbtract ( )   PDF (222KB) ( )  

Related Articles | Metrics

Objective To explore the effect of rmu-IFN-γ on the change of T cell subsets and natural killer cells of pregnant mice infected with T. gondii. Methods Early pregnant mice infected with T. gondii were administered with different doses（1 U/g or 10 U/g） of rmu-IFN-γ for three days before euthanasia. The numbers of splenic CD4+ and CD8+ T cells and natural killer cells were detected by flow cytometry. Results Compared with the infected mice that were not treated， the level of splenic CD4+ T cells in mice administered with two doses of rmu-IFN-γ increased on the day 10， 12， 14 of gestation， while the level of CD8+ T cells decreased on the day 10， 14 of gestation. The ratio of CD4+/CD8+ T cells increased significantly on the day 10， 12， 14 of gestation. Survival days of the two administered groups were longer than those of the infected group. Conclusion A proper dose of rmu-IFN-γ can reverse the decline of the ratio of T cell subsets， improve the proliferation of NK cells， and so increase the level of peripheral cellular immunity of pregnant mice.

Study on the Effect of Heluoshugan Capsule on Liver FibrosisInduced by Schistosoma japonicum Infection in Mice

TONGQiao-xia;WUYan-yan;XUBiao;LUODuan-de

2006, 24(2):  12-132. 

Asbtract ( )   PDF (304KB) ( )  

Related Articles | Metrics

Objective To investigate the effect of Chinese traditional medicine heluoshugan capsule on liver fibrosis induced by Schistosoma japonicum infection in mice. Methods Liver fibrosis in mice was established by Schistosoma japonicum infection in 6 weeks. Suspension of heluoshugan prepared with normal saline was given orally to the mice， 2 capsules for 20 mice daily for 8 weeks. The level of vascular endothelial growth factor （VEGF）、 focal adhesion kinase （FAK） and type I、 III collagen in liver tissue were detected by immuno-histochemistry. Results The results showed that heluoshugan improved the pathological change of the liver tissue， decreased the level of type I、 III collagen， espec-ially type III collagen （P<0.01）. The level of VEGF and FAK expression was inhibited after the administration of heluosh-ugan， though the level usually increased in liver fibrosis due to the infection. Conclusions The result suggests that heluoshugan capsule might have therapeutic effect on liver fibrosis induced by the infection of Schistosoma japonicum in mice， by inhibiting the activation of hepatic stellate cells and the pathological change of liver blood vessel.

专家论坛

Discussion on the Usage of Terminology of Some Parasites and Parasitic Diseases

WANGZhong-quan;CUIJing

2006, 24(2):  13-135. 

Asbtract ( )   PDF (179KB) ( )  

Related Articles | Metrics

According to the International Code of Zoological Nomenclature and the Standardized Nomenclature of Animal Parasitic Diseases （SNOAPAD）， and considering the new advances in parasitology， the usage of the terminology of some parasites and parasitic diseases （such as Trichinella and trichinellosis， filariae and filariasis， Echinococcus and echinococcosis， etc.） was discussed.

综述

Proteomics and Its Application in Parasitology

ZHAOQin-ping;JIANGMing-sen

2006, 24(2):  14-139. 

Asbtract ( )   PDF (228KB) ( )  

Related Articles | Metrics

Proteomics is an important high throughout method in modern life science. In this paper, the definition, background and methods used in proteomics were introduced, and the last part was focused on its application in parasitology.

Comparative Studies on the Difference Between Ascaris lumbricoides and Ascaris suum

WENGPei-lan;PENGWei-dong

2006, 24(2):  15-143. 

Asbtract ( )   PDF (230KB) ( )  

Related Articles | Metrics

There has been continued controversy on the taxonomy of Ascaris lumbricoides Linnaeus, 1758 from humans and Ascaris suum Goeze, 1782 from pigs. This article reviews a range of comparative studies related to host susceptibility， morphology, karyotype, immunology and biochemistry, as well as molecular genetics in recent years.

研究简报

Detection of Mycoplasma hominis in Trichomonas vaginalis by PCR

FANGShun-li;XIAOJian-chun;LUNZhao-rong

2006, 24(2):  16-145. 

Asbtract ( )   PDF (277KB) ( )  

Related Articles | Metrics

Twelve of 28 isolates of Trichomonas vaginalis collected from patients in hospitals in Guangzhou were found naturally infected with Mycoplasma hominis by PCR using specific primers. It suggests that the symbiosis of M. hominis in T. vaginalis also commonly occurs in China.

Antibody Detection in Sera of Patients with SchistosomiasisJaponica by Dot Immunogold Filtration Assay

XUJing;YANZi-zhu;ZHANGRui-jian;FENGTing;WUXiao-hua;ZHUDan;GUOJia-gang;ZHOUXiao-nong

2006, 24(2):  17-147. 

Asbtract ( )   PDF (247KB) ( )  

Related Articles | Metrics

Serum antibody of schistosomiasis patients was detected by dot immunogold filtration method (DIGFA) in laboratory and field, and F-ELISA was used as control. The results showed that there was no significant difference between these two assays in sensitivity and specificity（P>0.05）， with a high coincidence. DIGFA is easy to operate and may deserve a wide application in the diagnosis of schistosomiasis.

Inhibition of Quercetin on Liver Fibrosis due to Schistosoma japonicum Infection and on the Expression of Immediate Early Gene and Metalloproteinase 1 Inhibitor in Liver Tissue of Mice

XUBiao;HESheng-song;HANChun-rong

2006, 24(2):  18-149. 

Asbtract ( )   PDF (196KB) ( )  

Related Articles | Metrics

Quercetin and praziquantel were used to treat mice with hepatic fibrosis due to Schistosoma japonicum infection. Quercetin treatment obviously relieved the degree of hepatic fibrosis, significantly reduced the expression of immediate early gene, tissue inhibitor of metalloproteinase 1 （TIMP 1）, typesⅠ and Ⅲ collagen compared to the control. The expression of c-jun mRNA, typeⅠ and type Ⅲ collagen were reduced significantly compared to the group treated with praziquantel, whereas no difference in the expression of c-fos mRNA and TIMP1 between the two groups, indicating that quercetin may have better effect on schistosomal liver fibrosis than praziquantel in the long term.

Adjuvant Effect of CpG DNA Recombinant Plasmid onAntigen of Cysticercus cellulosae

JINGZhi-zhong;MENGXue-lian;WANGPei-ya;DOUYong-xi;LIHui;LUOXue-nong;ZHENGYa-dong;CAIXue-peng

2006, 24(2):  19-152. 

Asbtract ( )   PDF (247KB) ( )  

Related Articles | Metrics

In order to prove the adjuvant effect of CpG DNA recombinant plasmid, the total antibodies and their IgG2a subtype induced by antigen of Cysticercus cellulosae, and content of IL-4 and IFN-γ secreted from splenic cell of mouse immunized were measured. The recombinant plasmids showed an adjuvant effect, and CpG2 was the best adjuvant among the plasmids. It is proved that the CpG DNA possesses a synergistic effect with Al(OH)3 and 206 adjuvant, and is an effective Th1 type adjuvant in mice.

Induction of Protective Immunity Against Schistosoma japonicumBy pcDNA3.1/Sj20.8 Nucleic Acid Vaccine in BALB/c Mice

ZENGQiao;XIAOJian-hua;WANZhi-gang;LIAOLi;ZHANGYu-kuai;LIUChuan-ai;YANGQiu-lin

2006, 24(2):  20-155. 

Asbtract ( )   PDF (174KB) ( )  

Related Articles | Metrics

Sj20.8 gene was amplified by PCR and inserted into eukaryotic expression plasmid pcDNA3.1 to construct recombinant plasmid pcDNA3.1/Sj20.8， which was then injected into the quadriceps femoris of the BALB/c mice. Results showed that the Sj20.8 antigen was low expressed in the local tissue of the mice， and was not able to significantly reduce eggs in the liver than in the control mice.

Investigation of Demodex Infection Among Medical Students

WANGGuo-ying;ZHANGYun-sheng

2006, 24(2):  21-157. 

Asbtract ( )   PDF (282KB) ( )  

Related Articles | Metrics

Squeezing and smear method was used to detect Demodex infection for college students, the overall infection rate was 30.81% with Demodex folliculorum as the major one, D. brevis and mixed infection as the second ones. Certain relations were found between facial signs, lipid content and the infection. Prevalence was higher in those students who used to share washing materials (towels, etc.) with family members.

Epidemiological Surveillance after Filariasis TransmissionInterrupted in Jiangxi Province

ZHANGKun-zhao;LIZhi-hong;YANYu-fu;JINJin-yang;GONGYan-feng;QIUHai-qing;CHENDu;HUJian-guo

2006, 24(2):  22-159. 

Asbtract ( )   PDF (129KB) ( )  

Related Articles | Metrics

In 10 years after the interruption of filariasis transmission, the surveillance covered 29.5% of the townships and 3.7% of the population in the endemic areas, and 25.8% and 2.5% respectively after 10 years. No case with microfilaremia was found. 8 248 floating people were also blood-examined with negative result. No filarial larva was detected in 103 261 Culex quinquefasciatus dissected. Out of 703498 people investigated in 708 villages of 249 townships, 667 chronic filariasis patients were found. Among 2 928 people formerly with microfilaremia, no positive was found. The results indicate that Jiangxi Province has met the criteria of filaiasis elimination set by the Ministry of Health.