Objective To investigate the diversity and the distribution of host animal species of hantavirus and the effect on human health in Jiuhua Mountain area,China.Methods The host animal species of hantavirus was surveyed ...Objective To investigate the diversity and the distribution of host animal species of hantavirus and the effect on human health in Jiuhua Mountain area,China.Methods The host animal species of hantavirus was surveyed by using the trap method and the species diversity was evaluated by using the Simpson,Shannon-Weaner,and Pielou indices.Hantavirus antigens or antibodies in lung and blood samples of all the captured host animals were detected by direct or indirect immunofluorescence.Results Nine animal species of hantavirus were distributed in the forest ecosystem of Jiuhua Mountain.Of these,Niviventer confucianus and Apodemus agrarius were predominant,and N.confucianus,Rattus norvegicus,and Mus musculus had relatively large niche breadth index values.The host animals in the eastern and western mountain regions shared similar biodiversity index characteristics,predominant species,and species structures.Hantavirus was detected in 5 host animal species in Jiuhua Mountain area,the carriage rate of hantavirus was 6.03%.The average density of host animals in forest areas of the mountainous area was only 2.20%,and the virus infection rate in the healthy population was 2.33%.Conclusion The circulation of hantavirus was low in the forest areas of Jiuhua Mountain and did not pose a threat to human health.展开更多
To explore the feasibility of stable expression of Hantavirus H8205 strain G1 segment and human IL-2 fusion gene in Vero cells, and to examine the immune protection effects on mice vaccinated with this recombinant euk...To explore the feasibility of stable expression of Hantavirus H8205 strain G1 segment and human IL-2 fusion gene in Vero cells, and to examine the immune protection effects on mice vaccinated with this recombinant eukaryotic expression vector containing Hantavirus G1 gene and IL-2 gene. With the help of lipofectamine, the Vero cells were transfected with pcDNA3.1/HisB-IL-2-G1 and the positive cells were selected by G418. IFAT and SDS-PAGE elec- trophoresis were used to determine the stable transfection and expression of recombinant protein. Each mouse was inoculated with plasmids intramuscularly （i.m.） three times, 2 boosts were given at 2-week intervals, serum anti-hantavirus antibodies were detected by ELISA and neutralizing antibodies （NAb） were detected by Plaque Reduction Neutralization Test. The fusion protein expressed in Vero cells was 78 kD, corresponding to the estimated molecular size. The neutralizing antibody titers of mice with pcDNA3.1/HisB-IL-2-G1 were 1：20-1：80. IL-2/G1 fusion gene could be transferred in Vero cells and stably express the fusion protein. Specific humeral immune responses in mice can be induced with the recombinant eukaryotic expression vector containing the fusion gene, which lays the foundation for further development of therapeutic HTNV vaccine.展开更多
Monoclonal antibodies (McAb) to Hantavirus (HTV)were derived from the hybridoma fused with Lou/c plasmocytoma rat cells (IR983F) and spleen cells from lou/c inbred rat immunized with HTV Chen strain. Eleven cell lines...Monoclonal antibodies (McAb) to Hantavirus (HTV)were derived from the hybridoma fused with Lou/c plasmocytoma rat cells (IR983F) and spleen cells from lou/c inbred rat immunized with HTV Chen strain. Eleven cell lines producing monoclonal antibodies direc展开更多
Hantavirus is a zoonosis transmitted from rodents to humans. Asymptomatic infected rodents can secrete hantaviruses in the urine, feces, and saliva. The main route of infection transmission to human is aerosols contam...Hantavirus is a zoonosis transmitted from rodents to humans. Asymptomatic infected rodents can secrete hantaviruses in the urine, feces, and saliva. The main route of infection transmission to human is aerosols contaminated with the virus. This study was designed to evaluate the serological and molecular prevalence of hantavirus as an emerging zoonoses disease among street sweepers in Isfahan province, central Iran. Serum samples from 200 street sweepers in healthy condition and those with recent renal failure were tested by ELISA (IgM and IgG). Molecular analysis was subsequently applied for IgM positive cases. From these samples, 9 (4.5%) were positive, of which 2 (22.22%) were positive for both IgM and RT-PCR, while 7 (77.77%) were positive for IgG. The mean age and work experience of the positive cases were 39.7 and 11.5 respectively. According to our observations, all positive cases reported prevalence of rodents in their work place. The logistic regression test showed that the age and work experience were not risk factors for being positive, but prevalence of rodents in work place was a risk factor for being positive, when compared with negative cases. This is the first comprehensive study on the prevalence of hantavirus with positive results coming from Iranian population, which can raise the public awareness for the hantavirus infections as a public health threat.展开更多
BACKGROUND Serologic cross-reactivity between hantaviruses often complicates the interpretation of the results.AIM To analyze the diagnostic value of indirect immunofluorescence assay(IFA)and western blot(WB)in the di...BACKGROUND Serologic cross-reactivity between hantaviruses often complicates the interpretation of the results.AIM To analyze the diagnostic value of indirect immunofluorescence assay(IFA)and western blot(WB)in the diagnosis of hantavirus infections.METHODS One hundred eighty-eight serum samples from Puumala(PUUV)and Dobrava(DOBV)orthohantavirus infected patients were analyzed.Serology was performed using commercial tests(Euroimmun,Lübeck,Germany).RESULTS Using IFA,49.5%of acute-phase samples showed a monotypic response to PUUV,while 50.5% cross-reacted with other hantaviruses.The overall cross-reactivity was higher for immunoglobulin G(IgG)(50.0%)than for immunoglobulin M(IgM)(25.5%).PUUV IgM/IgG antibodies showed low/moderate reactivity with orthohantaviruses Hantaan(12.3%/31.5%),Seoul(7.5%/17.8%),DOBV(5.4%/28.1%),and Saaremaa(4.8%/15.7%).Both DOBV IgM and IgG antibodies were broadly reactive with Hantaan(76.2%/95.2%),Saaremaa(80.9%/83.3%),and Seoul(78.6%/85.7%)and moderate with PUUV(28.5%/38.1%).Using a WB,serotyping was successful in most cross-reactive samples(89.5%).CONCLUSION The presented results indicate that WB is more specific than IFA in the diagnosis of hantavirus infections,confirming serotype in most IFA cross-reactive samples.展开更多
The aim of this study is to further understand the genotype of Hantavirus （HV） from peripheral blood of patients with hemorrhagic fever with renal syndrome （HFRS） and the epidemiological significance of this disea...The aim of this study is to further understand the genotype of Hantavirus （HV） from peripheral blood of patients with hemorrhagic fever with renal syndrome （HFRS） and the epidemiological significance of this disease in Heilongjiang province in recent years. Thirty-one serum samples of clinically diagnosed patients with HFRS were examined by RT-PCR to decide the genetic subtype. On the basis of infection season, the serum samples were divided into two groups： winter （Nov, 2003--Feb, 2004）, spring and summer （April, 200d--Sep, 2004）. Further analysis was performed in combination with clinical symptoms. It was found that among the total 31 samples, 22 were sero-positive. Among 14 serum samples in winter, 8 were sero-positive, of which 5 cases were of type Ⅰ （Hantaan virus, HTNV） and 3 of type Ⅱ （Seoul virus, SEOV）. Among 17 samples in spring and summer, 14 were sero-positive, of which 5 cases were of type Ⅰ and 9 of type Ⅱ . So it concludes that both of the two types of Hantavirus exist in Heilongjiang. The type Ⅰ is the main pathogen of HFRS in winter, and typeⅡ is the main in spring and summer.展开更多
Hantaviruses are comprised of tri-segmented negative sense single-stranded RNA, and are members of the Bunyaviridae family. Hantaviruses are distributed worldwide and are important zoonotic pathogens that can have sev...Hantaviruses are comprised of tri-segmented negative sense single-stranded RNA, and are members of the Bunyaviridae family. Hantaviruses are distributed worldwide and are important zoonotic pathogens that can have severe adverse effects in humans. They are naturally maintained in specific reservoir hosts without inducing symptomatic infection. In humans, however,hantaviruses often cause two acute febrile diseases, hemorrhagic fever with renal syndrome(HFRS) and hantavirus cardiopulmonary syndrome(HCPS). In this paper, we review the epidemiology and epizootiology of hantavirus infections worldwide.展开更多
Objective To identify new recombinant antigens with potential for diagnosis of hemorrhagic fever with renal syndrom (HFRS) and establish reverse transcription-polymerase chain reaction-restriction fragments length po...Objective To identify new recombinant antigens with potential for diagnosis of hemorrhagic fever with renal syndrom (HFRS) and establish reverse transcription-polymerase chain reaction-restriction fragments length polymorphism (RT-PCR-RFLP) for genotyping of hantavirus.Methods One group of primers was used to clone the full-length S genome segment and the partial S genorme segment of the N-terminal. The two cloned genes were both fusionally expressed and nonfusionally expressed in the T7 system. The other group of primers was used to establish a RT-PCR method to detect RNAs in 37 virus isolates, 2 positive standard virus strains of hantavirus and 5 negative controls.The method for typing RFLP was set up by digesting the PCR products of 20 virus isolates with Ras Ⅰ and Hind Ⅲ.Results The non-fusionally expressed products with a working concentration of 1:10 000 by chapping enzyme-linked immunosorbent assay (cELISA), presented good biological activity though yields were lower than that of the fusionally expressed products.The specific component of the hantavirus genome (299 bp or 577 bp) wes seen in all viral samples. The genotyping of hantavirus showed that 9 out of the total were hantann (HTN) viruses, 8 were seol (SEO) viruses and 3 were not determined.Conclusions The good working titrer of expressed recombinant antigen showed that it has the potential to replace the natural antigen for detecting hantavirus antibodies. On comparison with cELISA, the detection rates for these two methods were 100% and 84.6%, and the coincidence rate was 84.6%. The former had a 15.4% higher sensitivity than the latter. The typing efficiency of RT-PCR-RFLP and sero-typing method was 85% (17/20) and 55% (11/20), respectively, showing that the former was 30% higher than the latter, while their results were highly consistant.展开更多
Hantavirus infection is a global health challenge,causing widespread public concern.In recent years,cases of hantavirus infection in pregnant women have been reported in many countries.The infected pregnant women and ...Hantavirus infection is a global health challenge,causing widespread public concern.In recent years,cases of hantavirus infection in pregnant women have been reported in many countries.The infected pregnant women and their fetuses appear to have more severe clinical symptoms and worse clinical outcomes.Hence,to study the prevalence of hantavirus infection in pregnant women,this study will focus on the epidemiological distribution of the virus,different virus species penetrating the placental barrier,and factors affecting the incidence and clinical outcome of the infection in pregnant women and their fetuses.In addition,this review will also discuss the diagnostic tools and treatments for pregnant patients and provide an overview of the relevant future research.展开更多
Background China is the most severe endemic area of hemorrhagic fever with renal syndrome （HFRS） in the world with 30 000-50 000 cases reported annually, which accounts for more than 90% of total number of cases wor...Background China is the most severe endemic area of hemorrhagic fever with renal syndrome （HFRS） in the world with 30 000-50 000 cases reported annually, which accounts for more than 90% of total number of cases worldwide. The incidence rate of the syndrome in Shandong Province is one of the highest in China, which has ever reached 50 per 100 000 persons per year. However, the molecular characteristics of hantaviruses （HV） epidemic in Shandong Province remain unclear. Therefore it is useful to clarify nucleotide sequence and phylogenetic characteristics of HV isolated in Shandong Province in order to provide better advices to control and prevent HFRS. Methods RNAs were extracted from sera of clinically diagnosed patients and positive rodent lungs that were detected by indirect immunofluorescent assay （IFA）. Partial M segments of HV were amplified from the RNAs with reverse transcription nested polymerase chain reactions （nested PCR） using hantavirus genotype specific primers. The nested PCR products were sequenced and compared with those from previously epidemic isolates in Shandong and with other representative HV sequences from GenBank. Phylogenetic tree analyses were performed based on the sequences of the M genes. Results Thirty-four HV isolates in Shandong showed 67.1%-100% nucleotide identities. The nucleotide homologies among 6 Hantaan viruses （HTNV） isolates in Shandong were 78.1%-98.7%, while the homologies among 28 Seoul virus （SEOV） isolates in Shandong were 93.7%-100%. There were at least 3 subtypes HTNV （H2, H5, H9） and 2 subtypes SEOV （S2, S3） in Shandong Province. Conclusions In Shandong Province, the homologies of HTNV were lower and there were no predominant subtypes, while the homologies of SEOV were higher and S3 was the predominant subtype. The homologies of SEOV from rodents were higher than those from patients. The distribution of subtypes in Shandong was similar to that of the adjoining provinces. Phylogenetic analyses of the sequences showed geographic clustering of HV in Shandong.展开更多
Background The heavy incidence and mortality of hemorrhagic fever with renal syndrome, as well as no specific drugs in curing the disease, clearly indicate the need for development Of the more effective hantavirus vac...Background The heavy incidence and mortality of hemorrhagic fever with renal syndrome, as well as no specific drugs in curing the disease, clearly indicate the need for development Of the more effective hantavirus vaccine. Refining the DNA vaccination strategy to elicit more clinically efficacious immune responses is now under intensive investigation. In the present study, we examined the effects of using an interleukin-12 expression plasmid as a genetic adjuvant to enhance the immune responses induced by a DNA vaccine based on the S gene encoding nucleocapsid protein against hantavirus. Methods BALB/c mice were immunized three times by intramuscular inoculations of DNA vaccine encoding of hantanvirus nucleoeapsid protein alone or in combination with a plasmid expressing murine interleukin-12 (pcIL-12). Booster immunizations were employed 2 times at 2-week interval. To evaluate the Immoral and cellular immune responses, antigen-specific lymphocyte proliferation and antibody production were assayed by MTT method and ELISA respectively. The level of interleukin-4 and interferon-gamma in the splenic lymphocytic cultured supernatant were detected with ELISA kit at day 5, 10, 17, 35 and 42 after primary immunization. Results Antigen-specific IgG antibodies was increased markedly at day 17 in the experiment groups and reached a plateau after day 35. As pcIL-12 co-injected, a significant inhibition of antigen-specific IgG levels was displayed over the period and the antibody mean titre was decreased to only about 1: 50 at day 42 after primary immunization, significantly lower than the group immunized with pcDNA3.1 + S alone, in which the mean titre was about 1:70. Interferon-gamma was increased remarkably by the co-injection of pcIL-12 compared with the injection of pcDNA3.1 + S alone. However, the production of interleukin-4 was inhibited by pcIL-12 coinjection. Furthermore, pcIL-12 co-injection efficiently enhanced antigen-specific lymphocyte proliferation. Conclusion Humoral and cytokine responses elicited by pcDNA3.1 + S inoculation can be modulated by coinoculation with pcIL-12 and efficiently induced Th1-dominant immune responses.展开更多
Background Hemorrhagic fever with renal syndrome （HFRS） is endemic in Junan county, Shandong Province, China. We conducted geographic information system （GIS）-based spatial analysis with the objective of estimatin...Background Hemorrhagic fever with renal syndrome （HFRS） is endemic in Junan county, Shandong Province, China. We conducted geographic information system （GIS）-based spatial analysis with the objective of estimating the spatial distribution of rodent populations and their hantavirus infection patterns, to describe the spatial relationships of hantavirus strains in small ecological areas and to identify key areas in endemic areas of HFRS for future public health planning and resource allocation.展开更多
基金supported by grants from the‘Twelfth Five-year Plan’from the Ministry of Science and Technology of China(2011BAD12B04-02)
文摘Objective To investigate the diversity and the distribution of host animal species of hantavirus and the effect on human health in Jiuhua Mountain area,China.Methods The host animal species of hantavirus was surveyed by using the trap method and the species diversity was evaluated by using the Simpson,Shannon-Weaner,and Pielou indices.Hantavirus antigens or antibodies in lung and blood samples of all the captured host animals were detected by direct or indirect immunofluorescence.Results Nine animal species of hantavirus were distributed in the forest ecosystem of Jiuhua Mountain.Of these,Niviventer confucianus and Apodemus agrarius were predominant,and N.confucianus,Rattus norvegicus,and Mus musculus had relatively large niche breadth index values.The host animals in the eastern and western mountain regions shared similar biodiversity index characteristics,predominant species,and species structures.Hantavirus was detected in 5 host animal species in Jiuhua Mountain area,the carriage rate of hantavirus was 6.03%.The average density of host animals in forest areas of the mountainous area was only 2.20%,and the virus infection rate in the healthy population was 2.33%.Conclusion The circulation of hantavirus was low in the forest areas of Jiuhua Mountain and did not pose a threat to human health.
基金This project was supported by a grant from the National Natural Sciences Foundation of China (No. 30170819)
文摘To explore the feasibility of stable expression of Hantavirus H8205 strain G1 segment and human IL-2 fusion gene in Vero cells, and to examine the immune protection effects on mice vaccinated with this recombinant eukaryotic expression vector containing Hantavirus G1 gene and IL-2 gene. With the help of lipofectamine, the Vero cells were transfected with pcDNA3.1/HisB-IL-2-G1 and the positive cells were selected by G418. IFAT and SDS-PAGE elec- trophoresis were used to determine the stable transfection and expression of recombinant protein. Each mouse was inoculated with plasmids intramuscularly （i.m.） three times, 2 boosts were given at 2-week intervals, serum anti-hantavirus antibodies were detected by ELISA and neutralizing antibodies （NAb） were detected by Plaque Reduction Neutralization Test. The fusion protein expressed in Vero cells was 78 kD, corresponding to the estimated molecular size. The neutralizing antibody titers of mice with pcDNA3.1/HisB-IL-2-G1 were 1：20-1：80. IL-2/G1 fusion gene could be transferred in Vero cells and stably express the fusion protein. Specific humeral immune responses in mice can be induced with the recombinant eukaryotic expression vector containing the fusion gene, which lays the foundation for further development of therapeutic HTNV vaccine.
文摘Monoclonal antibodies (McAb) to Hantavirus (HTV)were derived from the hybridoma fused with Lou/c plasmocytoma rat cells (IR983F) and spleen cells from lou/c inbred rat immunized with HTV Chen strain. Eleven cell lines producing monoclonal antibodies direc
文摘Hantavirus is a zoonosis transmitted from rodents to humans. Asymptomatic infected rodents can secrete hantaviruses in the urine, feces, and saliva. The main route of infection transmission to human is aerosols contaminated with the virus. This study was designed to evaluate the serological and molecular prevalence of hantavirus as an emerging zoonoses disease among street sweepers in Isfahan province, central Iran. Serum samples from 200 street sweepers in healthy condition and those with recent renal failure were tested by ELISA (IgM and IgG). Molecular analysis was subsequently applied for IgM positive cases. From these samples, 9 (4.5%) were positive, of which 2 (22.22%) were positive for both IgM and RT-PCR, while 7 (77.77%) were positive for IgG. The mean age and work experience of the positive cases were 39.7 and 11.5 respectively. According to our observations, all positive cases reported prevalence of rodents in their work place. The logistic regression test showed that the age and work experience were not risk factors for being positive, but prevalence of rodents in work place was a risk factor for being positive, when compared with negative cases. This is the first comprehensive study on the prevalence of hantavirus with positive results coming from Iranian population, which can raise the public awareness for the hantavirus infections as a public health threat.
文摘BACKGROUND Serologic cross-reactivity between hantaviruses often complicates the interpretation of the results.AIM To analyze the diagnostic value of indirect immunofluorescence assay(IFA)and western blot(WB)in the diagnosis of hantavirus infections.METHODS One hundred eighty-eight serum samples from Puumala(PUUV)and Dobrava(DOBV)orthohantavirus infected patients were analyzed.Serology was performed using commercial tests(Euroimmun,Lübeck,Germany).RESULTS Using IFA,49.5%of acute-phase samples showed a monotypic response to PUUV,while 50.5% cross-reacted with other hantaviruses.The overall cross-reactivity was higher for immunoglobulin G(IgG)(50.0%)than for immunoglobulin M(IgM)(25.5%).PUUV IgM/IgG antibodies showed low/moderate reactivity with orthohantaviruses Hantaan(12.3%/31.5%),Seoul(7.5%/17.8%),DOBV(5.4%/28.1%),and Saaremaa(4.8%/15.7%).Both DOBV IgM and IgG antibodies were broadly reactive with Hantaan(76.2%/95.2%),Saaremaa(80.9%/83.3%),and Seoul(78.6%/85.7%)and moderate with PUUV(28.5%/38.1%).Using a WB,serotyping was successful in most cross-reactive samples(89.5%).CONCLUSION The presented results indicate that WB is more specific than IFA in the diagnosis of hantavirus infections,confirming serotype in most IFA cross-reactive samples.
文摘The aim of this study is to further understand the genotype of Hantavirus （HV） from peripheral blood of patients with hemorrhagic fever with renal syndrome （HFRS） and the epidemiological significance of this disease in Heilongjiang province in recent years. Thirty-one serum samples of clinically diagnosed patients with HFRS were examined by RT-PCR to decide the genetic subtype. On the basis of infection season, the serum samples were divided into two groups： winter （Nov, 2003--Feb, 2004）, spring and summer （April, 200d--Sep, 2004）. Further analysis was performed in combination with clinical symptoms. It was found that among the total 31 samples, 22 were sero-positive. Among 14 serum samples in winter, 8 were sero-positive, of which 5 cases were of type Ⅰ （Hantaan virus, HTNV） and 3 of type Ⅱ （Seoul virus, SEOV）. Among 17 samples in spring and summer, 14 were sero-positive, of which 5 cases were of type Ⅰ and 9 of type Ⅱ . So it concludes that both of the two types of Hantavirus exist in Heilongjiang. The type Ⅰ is the main pathogen of HFRS in winter, and typeⅡ is the main in spring and summer.
基金supported by the National Natural Science Foundation of China (No. 81373118)the National Basic Research Programme of China (973 Programme No. 2012CB518905)
文摘Hantaviruses are comprised of tri-segmented negative sense single-stranded RNA, and are members of the Bunyaviridae family. Hantaviruses are distributed worldwide and are important zoonotic pathogens that can have severe adverse effects in humans. They are naturally maintained in specific reservoir hosts without inducing symptomatic infection. In humans, however,hantaviruses often cause two acute febrile diseases, hemorrhagic fever with renal syndrome(HFRS) and hantavirus cardiopulmonary syndrome(HCPS). In this paper, we review the epidemiology and epizootiology of hantavirus infections worldwide.
基金ThisstudywassupportedbytheNationalNaturalScienceFoundationofChina (No .396 70 6 45 )
文摘Objective To identify new recombinant antigens with potential for diagnosis of hemorrhagic fever with renal syndrom (HFRS) and establish reverse transcription-polymerase chain reaction-restriction fragments length polymorphism (RT-PCR-RFLP) for genotyping of hantavirus.Methods One group of primers was used to clone the full-length S genome segment and the partial S genorme segment of the N-terminal. The two cloned genes were both fusionally expressed and nonfusionally expressed in the T7 system. The other group of primers was used to establish a RT-PCR method to detect RNAs in 37 virus isolates, 2 positive standard virus strains of hantavirus and 5 negative controls.The method for typing RFLP was set up by digesting the PCR products of 20 virus isolates with Ras Ⅰ and Hind Ⅲ.Results The non-fusionally expressed products with a working concentration of 1:10 000 by chapping enzyme-linked immunosorbent assay (cELISA), presented good biological activity though yields were lower than that of the fusionally expressed products.The specific component of the hantavirus genome (299 bp or 577 bp) wes seen in all viral samples. The genotyping of hantavirus showed that 9 out of the total were hantann (HTN) viruses, 8 were seol (SEO) viruses and 3 were not determined.Conclusions The good working titrer of expressed recombinant antigen showed that it has the potential to replace the natural antigen for detecting hantavirus antibodies. On comparison with cELISA, the detection rates for these two methods were 100% and 84.6%, and the coincidence rate was 84.6%. The former had a 15.4% higher sensitivity than the latter. The typing efficiency of RT-PCR-RFLP and sero-typing method was 85% (17/20) and 55% (11/20), respectively, showing that the former was 30% higher than the latter, while their results were highly consistant.
基金supported by the National Scientific Research Program of China:New technology and project on intervention and elimination of cytokine storm and secondary infection in acute severe respiratory infectious diseases(2017ZX10204401-002-005)。
文摘Hantavirus infection is a global health challenge,causing widespread public concern.In recent years,cases of hantavirus infection in pregnant women have been reported in many countries.The infected pregnant women and their fetuses appear to have more severe clinical symptoms and worse clinical outcomes.Hence,to study the prevalence of hantavirus infection in pregnant women,this study will focus on the epidemiological distribution of the virus,different virus species penetrating the placental barrier,and factors affecting the incidence and clinical outcome of the infection in pregnant women and their fetuses.In addition,this review will also discuss the diagnostic tools and treatments for pregnant patients and provide an overview of the relevant future research.
基金This work was funded by NSFC(No.30671812)the Medical Development Foundation of Shandong Province Government,China(No.CX02207).
文摘Background China is the most severe endemic area of hemorrhagic fever with renal syndrome （HFRS） in the world with 30 000-50 000 cases reported annually, which accounts for more than 90% of total number of cases worldwide. The incidence rate of the syndrome in Shandong Province is one of the highest in China, which has ever reached 50 per 100 000 persons per year. However, the molecular characteristics of hantaviruses （HV） epidemic in Shandong Province remain unclear. Therefore it is useful to clarify nucleotide sequence and phylogenetic characteristics of HV isolated in Shandong Province in order to provide better advices to control and prevent HFRS. Methods RNAs were extracted from sera of clinically diagnosed patients and positive rodent lungs that were detected by indirect immunofluorescent assay （IFA）. Partial M segments of HV were amplified from the RNAs with reverse transcription nested polymerase chain reactions （nested PCR） using hantavirus genotype specific primers. The nested PCR products were sequenced and compared with those from previously epidemic isolates in Shandong and with other representative HV sequences from GenBank. Phylogenetic tree analyses were performed based on the sequences of the M genes. Results Thirty-four HV isolates in Shandong showed 67.1%-100% nucleotide identities. The nucleotide homologies among 6 Hantaan viruses （HTNV） isolates in Shandong were 78.1%-98.7%, while the homologies among 28 Seoul virus （SEOV） isolates in Shandong were 93.7%-100%. There were at least 3 subtypes HTNV （H2, H5, H9） and 2 subtypes SEOV （S2, S3） in Shandong Province. Conclusions In Shandong Province, the homologies of HTNV were lower and there were no predominant subtypes, while the homologies of SEOV were higher and S3 was the predominant subtype. The homologies of SEOV from rodents were higher than those from patients. The distribution of subtypes in Shandong was similar to that of the adjoining provinces. Phylogenetic analyses of the sequences showed geographic clustering of HV in Shandong.
文摘Background The heavy incidence and mortality of hemorrhagic fever with renal syndrome, as well as no specific drugs in curing the disease, clearly indicate the need for development Of the more effective hantavirus vaccine. Refining the DNA vaccination strategy to elicit more clinically efficacious immune responses is now under intensive investigation. In the present study, we examined the effects of using an interleukin-12 expression plasmid as a genetic adjuvant to enhance the immune responses induced by a DNA vaccine based on the S gene encoding nucleocapsid protein against hantavirus. Methods BALB/c mice were immunized three times by intramuscular inoculations of DNA vaccine encoding of hantanvirus nucleoeapsid protein alone or in combination with a plasmid expressing murine interleukin-12 (pcIL-12). Booster immunizations were employed 2 times at 2-week interval. To evaluate the Immoral and cellular immune responses, antigen-specific lymphocyte proliferation and antibody production were assayed by MTT method and ELISA respectively. The level of interleukin-4 and interferon-gamma in the splenic lymphocytic cultured supernatant were detected with ELISA kit at day 5, 10, 17, 35 and 42 after primary immunization. Results Antigen-specific IgG antibodies was increased markedly at day 17 in the experiment groups and reached a plateau after day 35. As pcIL-12 co-injected, a significant inhibition of antigen-specific IgG levels was displayed over the period and the antibody mean titre was decreased to only about 1: 50 at day 42 after primary immunization, significantly lower than the group immunized with pcDNA3.1 + S alone, in which the mean titre was about 1:70. Interferon-gamma was increased remarkably by the co-injection of pcIL-12 compared with the injection of pcDNA3.1 + S alone. However, the production of interleukin-4 was inhibited by pcIL-12 coinjection. Furthermore, pcIL-12 co-injection efficiently enhanced antigen-specific lymphocyte proliferation. Conclusion Humoral and cytokine responses elicited by pcDNA3.1 + S inoculation can be modulated by coinoculation with pcIL-12 and efficiently induced Th1-dominant immune responses.
基金This study was supported by a grant from the National Natural Science Foundation of China （No. 30471489）.
文摘Background Hemorrhagic fever with renal syndrome （HFRS） is endemic in Junan county, Shandong Province, China. We conducted geographic information system （GIS）-based spatial analysis with the objective of estimating the spatial distribution of rodent populations and their hantavirus infection patterns, to describe the spatial relationships of hantavirus strains in small ecological areas and to identify key areas in endemic areas of HFRS for future public health planning and resource allocation.
