Peter Gowland - Academia.edu (original) (raw)
Papers by Peter Gowland
Transfusion Clinique et Biologique
Transfusion Medicine and Hemotherapy, 2016
Transfusion, Oct 22, 2004
AIDS, Nov 1, 1998
Bruno Ledergerber* and the Swiss HIV Cohort Study § Objective: To clarify the relationship betwee... more Bruno Ledergerber* and the Swiss HIV Cohort Study § Objective: To clarify the relationship between the number of provirus-bearing peripheral blood mononuclear cells (PBMC) and HIV-1 disease progression during the natural history of infection. Design: Twenty-four HIV-1-infected subjects with known seroconversion dates and long-term follow-up were retrospectively identified using the Swiss HIV Cohort Database. PBMC specimens from this cohort were retrieved from storage for analysis. Methods: Infected PBMC equivalents were determined by HIV-1 DNA quantitative competitive (QC)-PCR. The results were analysed with respect to HIV-1 disease stage and compared with a mathematical model of long-term HIV-1 disease progression. Results: PBMC HIV-1 DNA did not correlate with major indices of disease progression, including time following primary infection, time before reaching a CD4 cell count less than 200 × 10 6 /l, and time before death. The number of PBMC harbouring HIV-1 provirus was relatively constant throughout the clinical stages of HIV-1 infection, consistent with simulated data from a mathematical model of longterm HIV-1 infection. We also showed that a biased interpretation of the QC-PCR data may arise when the values are expressed as HIV-1 DNA copies per PBMC or per CD4 cell. Conclusions: This analysis suggests that levels of provirus-bearing PBMC remain constant during the natural course of HIV-1 infection, whereas plasma virus load typically increases logarithmically during the same period. The hypothesis that plasma virus levels are directly related to the number of infected cells may deserve reconsideration.
Transfusion Medicine and Hemotherapy, 2009
Molecular and Cellular Biology, Sep 1, 1989
Transcription of the mouse mammary tumor virus DNA is known to be induced by several steroid horm... more Transcription of the mouse mammary tumor virus DNA is known to be induced by several steroid hormones. Using chimeric MMTV plasmids containing mutations within the hormone regulatory element, we have previously studied the regions required for the glucocorticoid response in mouse fibroblasts. Here we report the characterization of elements essential for the stimulation by progestins and androgens as compared with glucocorticoids. The same set of mutant plasmids was transfected into the human mammary tumor cell line T47D, and the specific transcripts were analyzed by an Si nuclease protection assay. Androgen-mediated stimulation, although weak, showed an extended sensitivity to mutations, with a slight preference for the proximal region. The results with progestin suggest that sequences within all the described sites protected by the receptor in vitro are required and that the promoter-proximal region (-128 to-78 from the RNA start site) is more important than the distal one (-190 to-160). Moreover, a binding site for nuclear factor I was not required for the progestin response, whereas it was required for glucocorticoids. Thus, the various steroid receptors play a role in the differential regulation of mouse mammary tumor virus transcription by recognizing distinct sequence differences in the hormone regulatory element and interacting with different factors bound to the promoter.
Journal of Virological Methods, Sep 1, 2014
The performance of the rapid confirmatory HIV 1/2 assay Geenius was compared with the conventiona... more The performance of the rapid confirmatory HIV 1/2 assay Geenius was compared with the conventional HIV 1/2 line immunoblot (INNO-LIA HIV I/II Score). One hundred HIV 1/2 confirmed positive samples from donors and patients and 136 negative screening samples from blood donors were evaluated with both assays. A 20 member performance panel consisting of different HIV 1 and 2 subtypes was also analysed. Ninety-nine of the confirmed HIV positive samples were positive with both assays. One sample was positive with the INNO-LIA HIV I/II Score but indeterminate with the Geenius HIV 1/2. From 136 negative blood donor samples (negative with a combo HIV assay and a highly sensitive ID-NAT), 125 were concordant negative. Six and five samples were incorrectly indeterminate with the INNO-LIA HIV I/II Score and the Geenius HIV 1/2, respectively. One sample was weak positive with the INNO-LIA HIV I/II Score but negative with the Geenius HIV 1/2. The 20 member performance showed equivalent results with both assays. The rapid assay showed a comparable sensitivity and specificity for confirmation for positive and negative HIV donor and patient samples as well for a 20 member performance panel.
Vox Sanguinis, Apr 1, 2009
Background and Objectives RH48 (JAL) is a low-incidence Rh antigen of unknown molecular backgroun... more Background and Objectives RH48 (JAL) is a low-incidence Rh antigen of unknown molecular background associated with weakened expression of RhCE antigens. The objective of this study was to establish the molecular basis of JAL. Materials and Methods Seventeen JAL+ samples, from seven black (one of them a Brazilian of mixed race: black/Caucasian), nine European Caucasians and one Asian individuals, were typed with anti-D,-C,-c,-E and-e. Some samples were also tested for V/VS and ce (f). Titration studies and flow cytometry were used to analyse the expression of the JAL antigen and genomic DNA sequencing of all RHCE exons was conducted on all samples. Routine genotyping for RHCE was carried out on all samples. Screening of RHD exons 1-10, which included detection of the DAU allele, was carried out on all except one of the black samples. The Caucasian samples and remaining black sample were screened for the DAU mutation 1136C>T (T379M). Results Six black individuals had the Dce haplotype with RHCE mutations 340C>T (R114W) and 733C>G (L245V) [V/VS] and the RHD mutation T379M [DAU]. One mixed race individual had the Dce haplotype with the RHCE mutation 340C>T (R114W) but without the V/VS or DAU mutation. Eight Caucasians had the DCe haplotype with the 340C>T mutation. One Caucasian and one Asian had the Dce haplotype with a different mutation in an adjacent nucleotide, 341G>A (R114Q). All Caucasian individuals were negative for the DAU mutation 1136C>T (T379M). Previously described weakness of CE-related Rh antigens when present in single dose on JAL+ samples of DCe and Dce haplotypes was observed. Weak expression of V/VS was observed in the three black samples tested and weakness of JAL was observed in the black samples compared to the Caucasian samples. Conclusion The same mutation (340C>T, R114W) in two different haplotypes (DCe and Dce) and another mutation (341G>A, R114Q) in one of these haplotypes (Dce) are associated with expression of the JAL antigen. One of the RHCE mutations detected in our samples (340C>T) has been previously described but not in association with the JAL antigen. Our results indicate that the previously described RhCeMA and ce s (340) alleles encode the JAL antigen. Expression of V/VS antigen is weakened in the presence of JAL and expression of JAL is usually weaker when associated with the Dce haplotype compared to DCe.
Transfusion, Jun 21, 2010
BACKGROUND: The risk of transfusion-transmitted hepatitis B virus (HBV) in Switzerland by testing... more BACKGROUND: The risk of transfusion-transmitted hepatitis B virus (HBV) in Switzerland by testing blood donors for hepatitis B surface antigen (HBsAg) alone has been historically estimated at 1:160,000 transfusions. The Swiss health authorities decided not to introduce mandatory antibody to hepatitis B core antigen (anti-HBc) testing but to evaluate the investigation of HBV nucleic acid testing (NAT). STUDY DESIGN AND METHODS: Between June 2007 and February 2009, a total of 306,000 donations were screened routinely for HBsAg and HBV DNA by triplex individual-donation (ID)-NAT (Ultrio assay on Tigris system, Gen-Probe/Novartis Diagnostics). ID-NAT repeatedly reactive donors were further characterized for HBV serologic markers and viral load by quantitative polymerase chain reaction. The relative sensitivity of screening for HBsAg, anti-HBc, and HBV DNA was assessed. The residual HBV transmission risk of NAT with or without anti-HBc and HBsAg was retrospectively estimated in a mathematical model. RESULTS: From the 306,000 blood donations, 31 were repeatedly Ultrio test reactive and confirmed HBV infected, of which 24 (77%) and 27 (87%) were HBsAg and anti-HBc positive, respectively. Seven HBV-NAT yields were identified (1:44,000), two pre-HBsAg window period (WP) donations (1:153,000) and five occult HBV infections (1:61,000). Introduction of ID-NAT reduced the risk of HBV WP transmission in repeat donors from 1:95,000 to 1:296,000. CONCLUSIONS: Triplex NAT screening reduced the HBV WP transmission risk approximately threefold. NAT alone was more efficacious than the combined use of HBsAg and anti-HBc. The data from this study led to the decision to introduce sensitive HBV-NAT screening in Switzerland. Our findings may be useful in designing more efficient and cost-effective HBV screening strategies in low-prevalence countries.
Viruses, Nov 23, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Methods in Enzymology, 1983
Publisher Summary A major breakthrough in DNA sequence analysis has been achieved by the gel to p... more Publisher Summary A major breakthrough in DNA sequence analysis has been achieved by the gel to paper transfer technique developed by Southern. It permits a rapid and precise analysis of the size distribution of a few specific DNA sequences among a mixture of many different sequences. The inherent simplicity of the method is captivating. A mixture of defined DNA fragments that have been separated electrophoretically in an agarose gel is denatured and transferred to a nitrocellulose filter by blotting. The fragments of interest are then selectively detected by annealing with a specific radioactive probe. The main limitation of the original method, as pointed out by Southern, is that binding to nitrocellulose of DNA fragments shorter than a few hundred base pairs decreases rapidly with size. An improved method of transfer to nitrocellulose overcomes this problem. Nitrocellulose and diazo papers are similar in sensitivity even for transfers of small DNA fragments. Transfer to nitrocellulose paper is probably preferable in most instances because it is simpler and cheaper. Transfer to diazo paper is recommended, however, when it is important that the same transfer be hybridized repeatedly with different labeled probes or when conditions (e.g., urea gels) interfere with transfer to nitrocellulose.
Antiviral Chemistry & Chemotherapy, Oct 1, 1995
N4-hexadecyl-5′-0-(4-monomethoxytrityl)-2′-deoxycytidine-3′-hydrogenphosphonate and 5′-0-(4-monom... more N4-hexadecyl-5′-0-(4-monomethoxytrityl)-2′-deoxycytidine-3′-hydrogenphosphonate and 5′-0-(4-monomethoxytrityl)-2′-deoxythymidine-3′-0-hydrogenphosphonate were condensed with 2′,3′-dideoxycytidine (ddC) according to the hydrogenphosphonate method to yield N4-hexadecyl-2′-deoxycytidylyl-(3′-5′)-2′,3′-dideoxycytidine (N4-hexadecyldC-ddC) and 2′-deoxythymidylyl-(3′-5′)-N4-palmitoyl-2′,3′-dideoxycytidine (dT-N4-palmddC). N4-palmitoyl-2′,3′-dideoxycytidine (N4-palmddC) was synthesized by reacting palmitic anhydride with ddC. Both dinucleoside phosphates have amphiphilic properties and represent a new class of ddC derivatives in which in the case of the dinucleosides, the ddC-5′-monophosphate is masked with lipophilic residues of variable stability. The ddC derivatives can be solubilized in water by micelle formation and, because they have lipophilic residues, they can be incorporated into the lipid membranes of liposomes. The ddC derivatives were shown to have antiviral activities comparable to those of AZT and ddC when tested in vitro against HIV-1-infected HeLa and H9 cells as well as infected human monocytes/macrophages.
PubMed, Mar 1, 2023
Background: Disease morbidity of tick-borne encephalitis (TBE) has been increasing over the last ... more Background: Disease morbidity of tick-borne encephalitis (TBE) has been increasing over the last decades. Since the 1990s, however, no extensive seroprevalence studies on TBE in humans have been performed in Switzerland. Here we assessed the prevalence of anti-TBE virus (TBEV) antibodies among different groups of the Swiss blood donor population. Materials and methods: The study was carried out from July 2014 to January 2015. Blood donors participating in the study (n=9,328) were asked to fill in a questionnaire relating to vaccination against or infection with different flaviviruses, and blood samples were collected. All samples were screened for the presence of anti-TBEV IgG antibodies using ELISA testing. Seropositivity rates in different groups of blood donors were compared using Chi square tests with Bonferroni correction. Results: In 2014 and 2015, 24.6% of healthy Swiss blood donors indicated vaccination against TBE. Among vaccinated blood donors, antibody prevalence was significantly higher in younger (<40y: 85.3%) than older individuals (≥40 to <55y: 80.0%, ≥55y: 76.7%; p=0.005). In non-vaccinated individuals, antibody prevalence was significantly higher in younger (<40y: 10.0%) than older (≥40 to <55y: 4.0%, ≥55y: 3.9%; p<0.005), male (6.8%) than female (3.7%, p<0.0001), and blood donors from endemic (7.0%) than border (6.2%) or non-endemic regions (4.2%, p<0.001). Possible asymptomatic infection, as defined by positive IgG ELISA results in blood donors indicating no vaccination against TBEV, was found in 5.6%. Discussion: Our data importantly complement the knowledge on TBEV vaccination rates and estimate the frequency of subclinical TBE in Switzerland.
Cellular and Molecular Life Sciences, 1986
Experientia 42 (1986), Birkhfiuser Verlag, CH-4010 Basel/Switzerland 303 patients, only 148 (48.8... more Experientia 42 (1986), Birkhfiuser Verlag, CH-4010 Basel/Switzerland 303 patients, only 148 (48.8 %) reacted to the vaccine. The influence of administered drugs on the weak response within the patient's group is discussed.
Transfusion Medicine and Hemotherapy, 2021
Background: Malaria is a mosquito-borne infectious disease caused by protozoan parasites of the g... more Background: Malaria is a mosquito-borne infectious disease caused by protozoan parasites of the genus Plasmodium. As migration of populations from endemic areas to Europe and overseas recreational travel to endemic regions increase, there is also a growing risk of transfusion-transmitted tropical diseases by blood components. Material and Methods: In the present study two routine Plasmodium spp. ELISA (CAPTIA™ Malaria EIA, Trinity Biotech, and Malaria EIA, Bio-Rad) were compared with a new commercial ELISA (ELISA IgG, EUROIMMUN). From December 1, 2015 until November 30, 2016, 1,096 plasma samples from blood donors with a potential risk of malaria infection were collected at two blood transfusion centres in Germany and Switzerland. Results: The samples were tested comparatively with the ELISA from EUROIMMUN and the routine test used at the respective centre. Thirty-four of 595 (5.7%) tested blood samples from centre 1 and 49 of 501 (9.8%) tested blood samples from centre 2 showed reactivity on either or both ELISAs. All 83 reactive samples were sent for confirmation to the Diagnostic Centre of the Swiss Tropical and Public Health Institute (Swiss TPH) in Basel, Switzerland. Sixteen samples, which previously were reactive in the routine Plasmodium spp. EIA assays, were proven positive after confirmation testing (i.e., 4 positive and 12 inconclusive results), indicating an anti-Plasmodium antibody prevalence in blood donations of 1.5%. From these 16 reactive samples, 13 were also detected by the index test, resulting in an assay sensitivity of 81.2%. A specificity of 98.6% was calculated (1,065/1,080 confirmed negative samples). The overall agreement with the reference centre was 95.8% in centre 1 and 94% in centre 2. Conclusion: The comparison of the new EUROIMMUN ELISA and the established CAPTIA™ Malaria EIA (Trinity Biotech) and Malaria EIA (BioRad) used for routine blood donor screening in two laboratory blood donation centres revealed that all tested ELISAs show comparable sensitivities and are equally suitable for anti-Plasmodium antibody screening in blood banks.
Antiviral Chemistry & Chemotherapy, Dec 1, 1994
N 4-hexadecyl-S'-O-(4-monomethoxytrityl)-2'-deoxycyti-. dine-3'-hydrogenphosphate was reacted wit... more N 4-hexadecyl-S'-O-(4-monomethoxytrityl)-2'-deoxycyti-. dine-3'-hydrogenphosphate was reacted with 3'-azido-2',3'-dideoxythymidine (AZT) according to the hydrogenphosphate method to yield N 4-hexadecyl-2'deoxycytidylyl-(3'-S')-3'-azido-2',3'-dideoxythymidi ne. N 4-palmitoyl-S'-O-(4-monomethoxytrityl)-2'-deoxycytidine-3'-(2-chlorophenyl)-phosphate was condensed to AZT using the triester method to give N 4-palmitoyl-2'-deoxycytidylyl-(3'-S')-3'-azido-2',3'-dideoxythymidine. Both dinucleosidephosphates have amphiphilic properties and represent a new class of AZT derivatives in which the polar AZT-S'-monophosphate is masked with lipophilic deoxycytidine residues of variable stability. The AZT derivatives are water soluble, by forming micelles, and as a result of their amphiphilic nature, they can be incorporated into the llpld membranes of Iiposomes. In contrast to the micellar drug preparations, the Iiposomal formulations were shown to exert no lytic activity on human erythrocytes. Both AZT derivatives have anti HIV-1 activity in vitro.
Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology, 1997
Journal of Infectious Diseases, 1994
A phase I/IIA clinical trial with the chimeric mouse-human monoclonal antibody CGP 47 439 to the ... more A phase I/IIA clinical trial with the chimeric mouse-human monoclonal antibody CGP 47 439 to the principal neutralization determinant in the V3 region of human immunodeficiency virus type 1 (HIV-1) strain IIIB envelope protein gp 120 is reported. The trial was an uncontrolled single-center, open-label, multidose tolerability, immunogenicity, and pharmacokinetic study in homosexual men with advanced HIV disease. Patient groups were formed on the basis of the reactivity of the antibody with the gp 120 of their HIV-1 isolates. Intravenous infusions of 1, 10, and 25 mg of antibody were followed by seven escalated doses of 50, 100, and 200 mg, every 3 weeks. The antibody was well tolerated; no toxicity was observed. Some patients showed a transient but insignificant antibody response to the antibody with no apparent adverse reactions or accelerated elimination of it. Substantial serum levels of the antibody were maintained with a mean t1/2 of 8-16 days. A virus burden reduction was observed in some patients
Objectives In a COVID-19 sero-surveillance cohort study with predominantly healthy and vaccinated... more Objectives In a COVID-19 sero-surveillance cohort study with predominantly healthy and vaccinated individuals, the objectives were (i) to investigate longitudinally the factors associated with the quantitative dynamics of anti-spike IgG antibody levels, (ii) to evaluate whether the antibody levels were associated with protection from SARS-CoV-2 infection and (iii) to assess whether the association was different in the pre-Omicron compared with the Omicron period. Methods The QuantiVac Euroimmun ELISA test was used to quantify anti-S1 IgG levels. The entire study period (16 months), the 11-month pre-Omicron period and the cross-sectional analysis prior to the Omicron surge included 3219, 2310 and 895 reactive serum samples from 949, 919 and 895 study participants, respectively. Mixed-effect linear, mixed-effect time-to-event and logistic regression models were used to achieve the objectives. Results Age and time since infection or vaccination were the only factors associated with a d...
Transfusion Clinique et Biologique
Transfusion Medicine and Hemotherapy, 2016
Transfusion, Oct 22, 2004
AIDS, Nov 1, 1998
Bruno Ledergerber* and the Swiss HIV Cohort Study § Objective: To clarify the relationship betwee... more Bruno Ledergerber* and the Swiss HIV Cohort Study § Objective: To clarify the relationship between the number of provirus-bearing peripheral blood mononuclear cells (PBMC) and HIV-1 disease progression during the natural history of infection. Design: Twenty-four HIV-1-infected subjects with known seroconversion dates and long-term follow-up were retrospectively identified using the Swiss HIV Cohort Database. PBMC specimens from this cohort were retrieved from storage for analysis. Methods: Infected PBMC equivalents were determined by HIV-1 DNA quantitative competitive (QC)-PCR. The results were analysed with respect to HIV-1 disease stage and compared with a mathematical model of long-term HIV-1 disease progression. Results: PBMC HIV-1 DNA did not correlate with major indices of disease progression, including time following primary infection, time before reaching a CD4 cell count less than 200 × 10 6 /l, and time before death. The number of PBMC harbouring HIV-1 provirus was relatively constant throughout the clinical stages of HIV-1 infection, consistent with simulated data from a mathematical model of longterm HIV-1 infection. We also showed that a biased interpretation of the QC-PCR data may arise when the values are expressed as HIV-1 DNA copies per PBMC or per CD4 cell. Conclusions: This analysis suggests that levels of provirus-bearing PBMC remain constant during the natural course of HIV-1 infection, whereas plasma virus load typically increases logarithmically during the same period. The hypothesis that plasma virus levels are directly related to the number of infected cells may deserve reconsideration.
Transfusion Medicine and Hemotherapy, 2009
Molecular and Cellular Biology, Sep 1, 1989
Transcription of the mouse mammary tumor virus DNA is known to be induced by several steroid horm... more Transcription of the mouse mammary tumor virus DNA is known to be induced by several steroid hormones. Using chimeric MMTV plasmids containing mutations within the hormone regulatory element, we have previously studied the regions required for the glucocorticoid response in mouse fibroblasts. Here we report the characterization of elements essential for the stimulation by progestins and androgens as compared with glucocorticoids. The same set of mutant plasmids was transfected into the human mammary tumor cell line T47D, and the specific transcripts were analyzed by an Si nuclease protection assay. Androgen-mediated stimulation, although weak, showed an extended sensitivity to mutations, with a slight preference for the proximal region. The results with progestin suggest that sequences within all the described sites protected by the receptor in vitro are required and that the promoter-proximal region (-128 to-78 from the RNA start site) is more important than the distal one (-190 to-160). Moreover, a binding site for nuclear factor I was not required for the progestin response, whereas it was required for glucocorticoids. Thus, the various steroid receptors play a role in the differential regulation of mouse mammary tumor virus transcription by recognizing distinct sequence differences in the hormone regulatory element and interacting with different factors bound to the promoter.
Journal of Virological Methods, Sep 1, 2014
The performance of the rapid confirmatory HIV 1/2 assay Geenius was compared with the conventiona... more The performance of the rapid confirmatory HIV 1/2 assay Geenius was compared with the conventional HIV 1/2 line immunoblot (INNO-LIA HIV I/II Score). One hundred HIV 1/2 confirmed positive samples from donors and patients and 136 negative screening samples from blood donors were evaluated with both assays. A 20 member performance panel consisting of different HIV 1 and 2 subtypes was also analysed. Ninety-nine of the confirmed HIV positive samples were positive with both assays. One sample was positive with the INNO-LIA HIV I/II Score but indeterminate with the Geenius HIV 1/2. From 136 negative blood donor samples (negative with a combo HIV assay and a highly sensitive ID-NAT), 125 were concordant negative. Six and five samples were incorrectly indeterminate with the INNO-LIA HIV I/II Score and the Geenius HIV 1/2, respectively. One sample was weak positive with the INNO-LIA HIV I/II Score but negative with the Geenius HIV 1/2. The 20 member performance showed equivalent results with both assays. The rapid assay showed a comparable sensitivity and specificity for confirmation for positive and negative HIV donor and patient samples as well for a 20 member performance panel.
Vox Sanguinis, Apr 1, 2009
Background and Objectives RH48 (JAL) is a low-incidence Rh antigen of unknown molecular backgroun... more Background and Objectives RH48 (JAL) is a low-incidence Rh antigen of unknown molecular background associated with weakened expression of RhCE antigens. The objective of this study was to establish the molecular basis of JAL. Materials and Methods Seventeen JAL+ samples, from seven black (one of them a Brazilian of mixed race: black/Caucasian), nine European Caucasians and one Asian individuals, were typed with anti-D,-C,-c,-E and-e. Some samples were also tested for V/VS and ce (f). Titration studies and flow cytometry were used to analyse the expression of the JAL antigen and genomic DNA sequencing of all RHCE exons was conducted on all samples. Routine genotyping for RHCE was carried out on all samples. Screening of RHD exons 1-10, which included detection of the DAU allele, was carried out on all except one of the black samples. The Caucasian samples and remaining black sample were screened for the DAU mutation 1136C>T (T379M). Results Six black individuals had the Dce haplotype with RHCE mutations 340C>T (R114W) and 733C>G (L245V) [V/VS] and the RHD mutation T379M [DAU]. One mixed race individual had the Dce haplotype with the RHCE mutation 340C>T (R114W) but without the V/VS or DAU mutation. Eight Caucasians had the DCe haplotype with the 340C>T mutation. One Caucasian and one Asian had the Dce haplotype with a different mutation in an adjacent nucleotide, 341G>A (R114Q). All Caucasian individuals were negative for the DAU mutation 1136C>T (T379M). Previously described weakness of CE-related Rh antigens when present in single dose on JAL+ samples of DCe and Dce haplotypes was observed. Weak expression of V/VS was observed in the three black samples tested and weakness of JAL was observed in the black samples compared to the Caucasian samples. Conclusion The same mutation (340C>T, R114W) in two different haplotypes (DCe and Dce) and another mutation (341G>A, R114Q) in one of these haplotypes (Dce) are associated with expression of the JAL antigen. One of the RHCE mutations detected in our samples (340C>T) has been previously described but not in association with the JAL antigen. Our results indicate that the previously described RhCeMA and ce s (340) alleles encode the JAL antigen. Expression of V/VS antigen is weakened in the presence of JAL and expression of JAL is usually weaker when associated with the Dce haplotype compared to DCe.
Transfusion, Jun 21, 2010
BACKGROUND: The risk of transfusion-transmitted hepatitis B virus (HBV) in Switzerland by testing... more BACKGROUND: The risk of transfusion-transmitted hepatitis B virus (HBV) in Switzerland by testing blood donors for hepatitis B surface antigen (HBsAg) alone has been historically estimated at 1:160,000 transfusions. The Swiss health authorities decided not to introduce mandatory antibody to hepatitis B core antigen (anti-HBc) testing but to evaluate the investigation of HBV nucleic acid testing (NAT). STUDY DESIGN AND METHODS: Between June 2007 and February 2009, a total of 306,000 donations were screened routinely for HBsAg and HBV DNA by triplex individual-donation (ID)-NAT (Ultrio assay on Tigris system, Gen-Probe/Novartis Diagnostics). ID-NAT repeatedly reactive donors were further characterized for HBV serologic markers and viral load by quantitative polymerase chain reaction. The relative sensitivity of screening for HBsAg, anti-HBc, and HBV DNA was assessed. The residual HBV transmission risk of NAT with or without anti-HBc and HBsAg was retrospectively estimated in a mathematical model. RESULTS: From the 306,000 blood donations, 31 were repeatedly Ultrio test reactive and confirmed HBV infected, of which 24 (77%) and 27 (87%) were HBsAg and anti-HBc positive, respectively. Seven HBV-NAT yields were identified (1:44,000), two pre-HBsAg window period (WP) donations (1:153,000) and five occult HBV infections (1:61,000). Introduction of ID-NAT reduced the risk of HBV WP transmission in repeat donors from 1:95,000 to 1:296,000. CONCLUSIONS: Triplex NAT screening reduced the HBV WP transmission risk approximately threefold. NAT alone was more efficacious than the combined use of HBsAg and anti-HBc. The data from this study led to the decision to introduce sensitive HBV-NAT screening in Switzerland. Our findings may be useful in designing more efficient and cost-effective HBV screening strategies in low-prevalence countries.
Viruses, Nov 23, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Methods in Enzymology, 1983
Publisher Summary A major breakthrough in DNA sequence analysis has been achieved by the gel to p... more Publisher Summary A major breakthrough in DNA sequence analysis has been achieved by the gel to paper transfer technique developed by Southern. It permits a rapid and precise analysis of the size distribution of a few specific DNA sequences among a mixture of many different sequences. The inherent simplicity of the method is captivating. A mixture of defined DNA fragments that have been separated electrophoretically in an agarose gel is denatured and transferred to a nitrocellulose filter by blotting. The fragments of interest are then selectively detected by annealing with a specific radioactive probe. The main limitation of the original method, as pointed out by Southern, is that binding to nitrocellulose of DNA fragments shorter than a few hundred base pairs decreases rapidly with size. An improved method of transfer to nitrocellulose overcomes this problem. Nitrocellulose and diazo papers are similar in sensitivity even for transfers of small DNA fragments. Transfer to nitrocellulose paper is probably preferable in most instances because it is simpler and cheaper. Transfer to diazo paper is recommended, however, when it is important that the same transfer be hybridized repeatedly with different labeled probes or when conditions (e.g., urea gels) interfere with transfer to nitrocellulose.
Antiviral Chemistry & Chemotherapy, Oct 1, 1995
N4-hexadecyl-5′-0-(4-monomethoxytrityl)-2′-deoxycytidine-3′-hydrogenphosphonate and 5′-0-(4-monom... more N4-hexadecyl-5′-0-(4-monomethoxytrityl)-2′-deoxycytidine-3′-hydrogenphosphonate and 5′-0-(4-monomethoxytrityl)-2′-deoxythymidine-3′-0-hydrogenphosphonate were condensed with 2′,3′-dideoxycytidine (ddC) according to the hydrogenphosphonate method to yield N4-hexadecyl-2′-deoxycytidylyl-(3′-5′)-2′,3′-dideoxycytidine (N4-hexadecyldC-ddC) and 2′-deoxythymidylyl-(3′-5′)-N4-palmitoyl-2′,3′-dideoxycytidine (dT-N4-palmddC). N4-palmitoyl-2′,3′-dideoxycytidine (N4-palmddC) was synthesized by reacting palmitic anhydride with ddC. Both dinucleoside phosphates have amphiphilic properties and represent a new class of ddC derivatives in which in the case of the dinucleosides, the ddC-5′-monophosphate is masked with lipophilic residues of variable stability. The ddC derivatives can be solubilized in water by micelle formation and, because they have lipophilic residues, they can be incorporated into the lipid membranes of liposomes. The ddC derivatives were shown to have antiviral activities comparable to those of AZT and ddC when tested in vitro against HIV-1-infected HeLa and H9 cells as well as infected human monocytes/macrophages.
PubMed, Mar 1, 2023
Background: Disease morbidity of tick-borne encephalitis (TBE) has been increasing over the last ... more Background: Disease morbidity of tick-borne encephalitis (TBE) has been increasing over the last decades. Since the 1990s, however, no extensive seroprevalence studies on TBE in humans have been performed in Switzerland. Here we assessed the prevalence of anti-TBE virus (TBEV) antibodies among different groups of the Swiss blood donor population. Materials and methods: The study was carried out from July 2014 to January 2015. Blood donors participating in the study (n=9,328) were asked to fill in a questionnaire relating to vaccination against or infection with different flaviviruses, and blood samples were collected. All samples were screened for the presence of anti-TBEV IgG antibodies using ELISA testing. Seropositivity rates in different groups of blood donors were compared using Chi square tests with Bonferroni correction. Results: In 2014 and 2015, 24.6% of healthy Swiss blood donors indicated vaccination against TBE. Among vaccinated blood donors, antibody prevalence was significantly higher in younger (<40y: 85.3%) than older individuals (≥40 to <55y: 80.0%, ≥55y: 76.7%; p=0.005). In non-vaccinated individuals, antibody prevalence was significantly higher in younger (<40y: 10.0%) than older (≥40 to <55y: 4.0%, ≥55y: 3.9%; p<0.005), male (6.8%) than female (3.7%, p<0.0001), and blood donors from endemic (7.0%) than border (6.2%) or non-endemic regions (4.2%, p<0.001). Possible asymptomatic infection, as defined by positive IgG ELISA results in blood donors indicating no vaccination against TBEV, was found in 5.6%. Discussion: Our data importantly complement the knowledge on TBEV vaccination rates and estimate the frequency of subclinical TBE in Switzerland.
Cellular and Molecular Life Sciences, 1986
Experientia 42 (1986), Birkhfiuser Verlag, CH-4010 Basel/Switzerland 303 patients, only 148 (48.8... more Experientia 42 (1986), Birkhfiuser Verlag, CH-4010 Basel/Switzerland 303 patients, only 148 (48.8 %) reacted to the vaccine. The influence of administered drugs on the weak response within the patient's group is discussed.
Transfusion Medicine and Hemotherapy, 2021
Background: Malaria is a mosquito-borne infectious disease caused by protozoan parasites of the g... more Background: Malaria is a mosquito-borne infectious disease caused by protozoan parasites of the genus Plasmodium. As migration of populations from endemic areas to Europe and overseas recreational travel to endemic regions increase, there is also a growing risk of transfusion-transmitted tropical diseases by blood components. Material and Methods: In the present study two routine Plasmodium spp. ELISA (CAPTIA™ Malaria EIA, Trinity Biotech, and Malaria EIA, Bio-Rad) were compared with a new commercial ELISA (ELISA IgG, EUROIMMUN). From December 1, 2015 until November 30, 2016, 1,096 plasma samples from blood donors with a potential risk of malaria infection were collected at two blood transfusion centres in Germany and Switzerland. Results: The samples were tested comparatively with the ELISA from EUROIMMUN and the routine test used at the respective centre. Thirty-four of 595 (5.7%) tested blood samples from centre 1 and 49 of 501 (9.8%) tested blood samples from centre 2 showed reactivity on either or both ELISAs. All 83 reactive samples were sent for confirmation to the Diagnostic Centre of the Swiss Tropical and Public Health Institute (Swiss TPH) in Basel, Switzerland. Sixteen samples, which previously were reactive in the routine Plasmodium spp. EIA assays, were proven positive after confirmation testing (i.e., 4 positive and 12 inconclusive results), indicating an anti-Plasmodium antibody prevalence in blood donations of 1.5%. From these 16 reactive samples, 13 were also detected by the index test, resulting in an assay sensitivity of 81.2%. A specificity of 98.6% was calculated (1,065/1,080 confirmed negative samples). The overall agreement with the reference centre was 95.8% in centre 1 and 94% in centre 2. Conclusion: The comparison of the new EUROIMMUN ELISA and the established CAPTIA™ Malaria EIA (Trinity Biotech) and Malaria EIA (BioRad) used for routine blood donor screening in two laboratory blood donation centres revealed that all tested ELISAs show comparable sensitivities and are equally suitable for anti-Plasmodium antibody screening in blood banks.
Antiviral Chemistry & Chemotherapy, Dec 1, 1994
N 4-hexadecyl-S'-O-(4-monomethoxytrityl)-2'-deoxycyti-. dine-3'-hydrogenphosphate was reacted wit... more N 4-hexadecyl-S'-O-(4-monomethoxytrityl)-2'-deoxycyti-. dine-3'-hydrogenphosphate was reacted with 3'-azido-2',3'-dideoxythymidine (AZT) according to the hydrogenphosphate method to yield N 4-hexadecyl-2'deoxycytidylyl-(3'-S')-3'-azido-2',3'-dideoxythymidi ne. N 4-palmitoyl-S'-O-(4-monomethoxytrityl)-2'-deoxycytidine-3'-(2-chlorophenyl)-phosphate was condensed to AZT using the triester method to give N 4-palmitoyl-2'-deoxycytidylyl-(3'-S')-3'-azido-2',3'-dideoxythymidine. Both dinucleosidephosphates have amphiphilic properties and represent a new class of AZT derivatives in which the polar AZT-S'-monophosphate is masked with lipophilic deoxycytidine residues of variable stability. The AZT derivatives are water soluble, by forming micelles, and as a result of their amphiphilic nature, they can be incorporated into the llpld membranes of Iiposomes. In contrast to the micellar drug preparations, the Iiposomal formulations were shown to exert no lytic activity on human erythrocytes. Both AZT derivatives have anti HIV-1 activity in vitro.
Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology, 1997
Journal of Infectious Diseases, 1994
A phase I/IIA clinical trial with the chimeric mouse-human monoclonal antibody CGP 47 439 to the ... more A phase I/IIA clinical trial with the chimeric mouse-human monoclonal antibody CGP 47 439 to the principal neutralization determinant in the V3 region of human immunodeficiency virus type 1 (HIV-1) strain IIIB envelope protein gp 120 is reported. The trial was an uncontrolled single-center, open-label, multidose tolerability, immunogenicity, and pharmacokinetic study in homosexual men with advanced HIV disease. Patient groups were formed on the basis of the reactivity of the antibody with the gp 120 of their HIV-1 isolates. Intravenous infusions of 1, 10, and 25 mg of antibody were followed by seven escalated doses of 50, 100, and 200 mg, every 3 weeks. The antibody was well tolerated; no toxicity was observed. Some patients showed a transient but insignificant antibody response to the antibody with no apparent adverse reactions or accelerated elimination of it. Substantial serum levels of the antibody were maintained with a mean t1/2 of 8-16 days. A virus burden reduction was observed in some patients
Objectives In a COVID-19 sero-surveillance cohort study with predominantly healthy and vaccinated... more Objectives In a COVID-19 sero-surveillance cohort study with predominantly healthy and vaccinated individuals, the objectives were (i) to investigate longitudinally the factors associated with the quantitative dynamics of anti-spike IgG antibody levels, (ii) to evaluate whether the antibody levels were associated with protection from SARS-CoV-2 infection and (iii) to assess whether the association was different in the pre-Omicron compared with the Omicron period. Methods The QuantiVac Euroimmun ELISA test was used to quantify anti-S1 IgG levels. The entire study period (16 months), the 11-month pre-Omicron period and the cross-sectional analysis prior to the Omicron surge included 3219, 2310 and 895 reactive serum samples from 949, 919 and 895 study participants, respectively. Mixed-effect linear, mixed-effect time-to-event and logistic regression models were used to achieve the objectives. Results Age and time since infection or vaccination were the only factors associated with a d...