AIM:To investigate molecular phenotypes of myocardial B19V-infection to determine the role of B19V in myocarditis and dilated cardiomyopathy(DCM).METHODS:Endomyocardial biopsies(EMBs) from 498 B19V-positive patients w...AIM:To investigate molecular phenotypes of myocardial B19V-infection to determine the role of B19V in myocarditis and dilated cardiomyopathy(DCM).METHODS:Endomyocardial biopsies(EMBs) from 498 B19V-positive patients with myocarditis and DCMwere analyzed using molecular methods and functional experiments.EMBs were obtained from the University Hospitals of Greifswald and Tuebingen and additionally from 36 German cardiology centers.Control tissues were obtained at autopsy from 34 victims of accidents,crime or suicide.Identification of mononuclear cell infiltrates in EMBs was performed using immunohistological staining.Anti-B19V-IgM and anti-B19V-IgG were analyzed by enzyme-linked immunosorbent assay(ELISA).B19V viral loads were determined using in-house quantitative real-time polymerase chain reaction(PCR).For B19V-genotyping a new B19V-genotype-specific restriction fragment length polymorphism(RFLP)-PCR was established.B19V-genotyping was verified by direct DNAsequencing and sequences were aligned using BLAST and BioEdit software.B19V P6-promoter and HHV6-U94-transactivator constructs were generated for cell culture experiments.Transfection experiments were conducted using human endothelial cells 1.Luciferase reporter assays were performed to determine B19Vreplication activity.Statistical analysis and graphical representation were calculated using SPSS and Prism5 software.RESULTS:The prevalence of B19V was significantly more likely to be associated with inflammatory cardiomyopathy(iCMP) compared to uninflamed DCM(59.6% vs 35.3%)(P < 0.0001).The detection of B19V-mRNA replication intermediates proved that replication of B19V was present.RFLP-PCR assays showed that B19V-genotype 1(57.4%) and B19V-genotype 2(36.7%) were the most prevalent viral genotypes.B19V-genotype 2 was observed more frequently in EMBs with iCMP(65.0%) compared to DCM(35%)(P = 0.049).Although there was no significant difference in gender-specific B19V-loads,women were more frequently infected with B19V-genotype 2(44.6%) than men(36.0%)(P = 0.0448).Coinfection with B19V and other cardiotropic viruses was found in 19.2% of tissuesamples and was associated with higher B19V viral load compared to B19V-monoinfected tissue(P = 0.0012).The most frequent coinfecting virus was human herpes virus 6(HHV6,16.5%).B19V-coinfection with HHV6 showed higher B19V-loads compared to B19V-monoinfected EMBs(P = 0.0033),suggesting that HHV6 had transactivated B19V.In vitro experiments confirmed a 2.4-fold increased B19V P6-promoter activity by the HHV6 U94-transactivator.CONCLUSION:The finding of significantly increased B19V loads in patients with histologically proven cardiac inflammation suggests a crucial role of B19V-genotypes and reactivation of B19V-infection by HHV6-coinfection in B19V-associated iCMP.Our findings suggest that B19V-infection of the human heart can be a causative event for the development of an endothelial cell-mediated inflammatory disease and that this is related to both viral load and genotype.展开更多
Objective: To determine the seroprevalence of B19V IgM as a measure of acute infection and associated risk factors among < 5 years children at Oyo state, Nigeria. Methods: One hundred and sixteen (116) and thirty e...Objective: To determine the seroprevalence of B19V IgM as a measure of acute infection and associated risk factors among < 5 years children at Oyo state, Nigeria. Methods: One hundred and sixteen (116) and thirty eight (38) blood samples were individually collected from severe anaemia and age-matched non-anaemic children between 1-60 months old at Oyo state, Nigeria. EDTA anticoagulated blood was tested for their packed cell volume, while sera were tested for human parvovirus IgM antibodies using microhaematocrit centrifuge and Enzyme Linked Immunosorbent Assay, respectively. Interviewer-based questionnaires were used to collect participants' sociodemographic variables. Results: Anti-B19V IgM was detected in 17 (14.7%) severe anaemia subjects, whereas, only 2 (5.3%) non-anaemia subjects had B19V IgM. The prevalence of parvovirus B19 IgM antibodywas higher in anaemic subjects than non-anaemic control group. There is significant association between the seroprevalence of anti-B19V IgM and family size (P=0.001), number of siblings (P=0.032) and education status (P=0.01) of anaemic children but seroprevalence of anti-B19V IgM is not significantly associated with gender, family type and age (P>0.05). Conclusions: The seroprevalence of 14.7% among anaemic children confirm that these infections are endemic in Nigeria. This level of infectivity suggests that there is a high risk of transmission to healthy children as well as children with underlying haemolytic or acquired anaemia in Nigeria.展开更多
基金Supported by Grants of the Deutsche Forschungsgemeinschaft,Sonderforschungsbereich-Transregio 19(project B5)
文摘AIM:To investigate molecular phenotypes of myocardial B19V-infection to determine the role of B19V in myocarditis and dilated cardiomyopathy(DCM).METHODS:Endomyocardial biopsies(EMBs) from 498 B19V-positive patients with myocarditis and DCMwere analyzed using molecular methods and functional experiments.EMBs were obtained from the University Hospitals of Greifswald and Tuebingen and additionally from 36 German cardiology centers.Control tissues were obtained at autopsy from 34 victims of accidents,crime or suicide.Identification of mononuclear cell infiltrates in EMBs was performed using immunohistological staining.Anti-B19V-IgM and anti-B19V-IgG were analyzed by enzyme-linked immunosorbent assay(ELISA).B19V viral loads were determined using in-house quantitative real-time polymerase chain reaction(PCR).For B19V-genotyping a new B19V-genotype-specific restriction fragment length polymorphism(RFLP)-PCR was established.B19V-genotyping was verified by direct DNAsequencing and sequences were aligned using BLAST and BioEdit software.B19V P6-promoter and HHV6-U94-transactivator constructs were generated for cell culture experiments.Transfection experiments were conducted using human endothelial cells 1.Luciferase reporter assays were performed to determine B19Vreplication activity.Statistical analysis and graphical representation were calculated using SPSS and Prism5 software.RESULTS:The prevalence of B19V was significantly more likely to be associated with inflammatory cardiomyopathy(iCMP) compared to uninflamed DCM(59.6% vs 35.3%)(P < 0.0001).The detection of B19V-mRNA replication intermediates proved that replication of B19V was present.RFLP-PCR assays showed that B19V-genotype 1(57.4%) and B19V-genotype 2(36.7%) were the most prevalent viral genotypes.B19V-genotype 2 was observed more frequently in EMBs with iCMP(65.0%) compared to DCM(35%)(P = 0.049).Although there was no significant difference in gender-specific B19V-loads,women were more frequently infected with B19V-genotype 2(44.6%) than men(36.0%)(P = 0.0448).Coinfection with B19V and other cardiotropic viruses was found in 19.2% of tissuesamples and was associated with higher B19V viral load compared to B19V-monoinfected tissue(P = 0.0012).The most frequent coinfecting virus was human herpes virus 6(HHV6,16.5%).B19V-coinfection with HHV6 showed higher B19V-loads compared to B19V-monoinfected EMBs(P = 0.0033),suggesting that HHV6 had transactivated B19V.In vitro experiments confirmed a 2.4-fold increased B19V P6-promoter activity by the HHV6 U94-transactivator.CONCLUSION:The finding of significantly increased B19V loads in patients with histologically proven cardiac inflammation suggests a crucial role of B19V-genotypes and reactivation of B19V-infection by HHV6-coinfection in B19V-associated iCMP.Our findings suggest that B19V-infection of the human heart can be a causative event for the development of an endothelial cell-mediated inflammatory disease and that this is related to both viral load and genotype.
文摘Objective: To determine the seroprevalence of B19V IgM as a measure of acute infection and associated risk factors among < 5 years children at Oyo state, Nigeria. Methods: One hundred and sixteen (116) and thirty eight (38) blood samples were individually collected from severe anaemia and age-matched non-anaemic children between 1-60 months old at Oyo state, Nigeria. EDTA anticoagulated blood was tested for their packed cell volume, while sera were tested for human parvovirus IgM antibodies using microhaematocrit centrifuge and Enzyme Linked Immunosorbent Assay, respectively. Interviewer-based questionnaires were used to collect participants' sociodemographic variables. Results: Anti-B19V IgM was detected in 17 (14.7%) severe anaemia subjects, whereas, only 2 (5.3%) non-anaemia subjects had B19V IgM. The prevalence of parvovirus B19 IgM antibodywas higher in anaemic subjects than non-anaemic control group. There is significant association between the seroprevalence of anti-B19V IgM and family size (P=0.001), number of siblings (P=0.032) and education status (P=0.01) of anaemic children but seroprevalence of anti-B19V IgM is not significantly associated with gender, family type and age (P>0.05). Conclusions: The seroprevalence of 14.7% among anaemic children confirm that these infections are endemic in Nigeria. This level of infectivity suggests that there is a high risk of transmission to healthy children as well as children with underlying haemolytic or acquired anaemia in Nigeria.
