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1.
Nat Commun ; 12(1): 2518, 2021 05 04.
Article in English | MEDLINE | ID: mdl-33947856

ABSTRACT

Immunization with Plasmodium falciparum (Pf) sporozoites under chemoprophylaxis (PfSPZ-CVac) is the most efficacious approach to malaria vaccination. Implementation is hampered by a complex chemoprophylaxis regimen and missing evidence for efficacy against heterologous infection. We report the results of a double-blinded, randomized, placebo-controlled trial of a simplified, condensed immunization regimen in malaria-naive volunteers (EudraCT-Nr: 2018-004523-36). Participants are immunized by direct venous inoculation of 1.1 × 105 aseptic, purified, cryopreserved PfSPZ (PfSPZ Challenge) of the PfNF54 strain or normal saline (placebo) on days 1, 6 and 29, with simultaneous oral administration of 10 mg/kg chloroquine base. Primary endpoints are vaccine efficacy tested by controlled human malaria infection (CHMI) using the highly divergent, heterologous strain Pf7G8 and safety. Twelve weeks following immunization, 10/13 participants in the vaccine group are sterilely protected against heterologous CHMI, while (5/5) participants receiving placebo develop parasitemia (risk difference: 77%, p = 0.004, Boschloo's test). Immunization is well tolerated with self-limiting grade 1-2 headaches, pyrexia and fatigue that diminish with each vaccination. Immunization induces 18-fold higher anti-Pf circumsporozoite protein (PfCSP) antibody levels in protected than in unprotected vaccinees (p = 0.028). In addition anti-PfMSP2 antibodies are strongly protection-associated by protein microarray assessment. This PfSPZ-CVac regimen is highly efficacious, simple, safe, well tolerated and highly immunogenic.


Subject(s)
Malaria Vaccines/immunology , Malaria, Falciparum/prevention & control , Plasmodium falciparum/immunology , Vaccination/methods , Vaccines, Attenuated/immunology , Adult , Antimalarials/therapeutic use , Cell Line , Chemoprevention , Chloroquine/therapeutic use , Female , Humans , Immunoglobulin G/immunology , Malaria Vaccines/adverse effects , Malaria, Falciparum/drug therapy , Malaria, Falciparum/immunology , Malaria, Falciparum/parasitology , Male , Parasitemia/immunology , Protein Array Analysis , Sporozoites/immunology , Vaccination/adverse effects , Vaccines, Attenuated/adverse effects
2.
Preprint in English | medRxiv | ID: ppmedrxiv-20225359

ABSTRACT

BackgroundHealth conditions and immune dysfunction associated with trisomy 21 (Down syndrome, DS) may impact the clinical course of COVID-19 once infected by SARS-CoV-2. MethodsThe T21RS COVID-19 Initiative launched an international survey for clinicians or caregivers/family members on patients with COVID-19 and DS (N=1046). De-identified survey data collected between April and October 2020 were analysed and compared with the UK ISARIC4C survey of hospitalized COVID-19 patients with and without DS. COVID-19 patients with DS from the ISARIC4C survey (ISARIC4C DS cases=100) were matched to a random set of patients without DS (ISARIC4C controls=400) and hospitalized DS cases in the T21RS survey (T21RS DS cases=100) based on age, gender, and ethnicity. FindingThe mean age in the T21RS survey was 29 years (SD=18), 73% lived with their family. Similar to the general population, the most frequent signs and symptoms of COVID-19 were fever, cough, and shortness of breath. Pain and nausea were reported less frequently (p<0.01), whereas altered consciousness/confusion were reported more frequently (p<0.01). Risk factors for hospitalization and mortality were similar to the general population (age, male gender, diabetes, obesity, dementia) with the addition of congenital heart defects as a risk factor for hospitalization. Mortality rates showed a rapid increase from age 40 and were higher than for controls (T21RS DS versus controls: risk ratio (RR)=3.5 (95%-CI=2.6;4.4), ISARIC4C DS versus controls: RR=2.9 (95%-CI=2.1;3.8)) even after adjusting for known risk factors for COVID-19 mortality. InterpretationLeading signs/symptoms of COVID-19 and risk factors for severe disease course are similar to the general population. However, individuals with DS present significantly higher rates of mortality, especially from age 40. FundingDown Syndrome Affiliates in Action, Down Syndrome Medical Interest Group-USA, GiGis Playhouse, Jerome Lejeune Foundation, LuMind IDSC Foundation, Matthews Foundation, National Down Syndrome Society, National Task Group on Intellectual Disabilities and Dementia Practices.

3.
Ecol Evol ; 10(12): 5431-5439, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32607164

ABSTRACT

Common carp (Cyprinus carpio) has an outstanding economic importance in freshwater aquaculture due to its high adaptive capacity to both food and environment. In fact, it is the third most farmed fish species worldwide according to the Food and Agriculture Organization. More than four million tons of common carp are produced annually in aquaculture, and more than a hundred thousand tons are caught from the wild. Historically, the common carp was also the first fish species to be domesticated in ancient China, and now, there is a huge variety of domestic carp strains worldwide. In the present study, we used double digestion restriction site-associated DNA sequencing to genotype several European common carp strains and showed that they are divided into two distinct groups. One of them includes central European common carp strains as well as Ponto-Caspian wild common carp populations, whereas the other group contains several common carp strains that originated in the Soviet Union, mostly as cold-resistant strains. We believe that breeding with wild Amur carp and subsequent selection of the hybrids for resistance to adverse environmental conditions was the attribute of the second group. We assessed the contribution of wild Amur carp inheritance to the common carp strains and discovered discriminating genes, which differed in allele frequencies between groups. Taken together, our results improve our current understanding of the genetic variability of common carp, namely the structure of natural and artificial carp populations, and the contribution of wild carp traits to domestic strains.

4.
Malar J ; 18(1): 424, 2019 Dec 16.
Article in English | MEDLINE | ID: mdl-31842893

ABSTRACT

BACKGROUND: Malaria remains a major public health problem, affecting mainly low-and middle-income countries. The management of this parasitic disease is challenged by ever increasing drug resistance. This study, investigated the therapeutic efficacy, tolerability and safety of artemether-lumefantrine (AL) and artesunate-amodiaquine (AS-AQ), used as first-line drugs to treat uncomplicated malaria in Lambaréné, Gabon. METHODS: A non-randomized clinical trial was conducted between October 2017 and March 2018 to assess safety, clinical and parasitological efficacy of fixed-doses of AL and AS-AQ administered to treat uncomplicated Plasmodium falciparum malaria in children aged from 6 months to 12 years. After 50 children were treated with AL, another 50 children received ASAQ. The 2009 World Health Organization protocol for monitoring of the efficacy of anti­malarial drugs was followed. Molecular markers msp1 and msp2 were used to differentiate recrudescence and reinfection. For the investigation of artemisinin resistant markers, gene mutations in Pfk13 were screened. RESULTS: Per-protocol analysis on day 28 showed a PCR corrected cure rate of 97% (95% CI 86-100) and 95% (95% CI 84-99) for AL and AS-AQ, respectively. The most frequent adverse event in both groups was asthenia. No mutations in the kelch-13 gene associated with artemisinin resistance were identified. All participants had completed microscopic parasite clearance by day 3 post-treatment. CONCLUSION: This study showed that AL and AS-AQ remain efficacious, well-tolerated, and are safe to treat uncomplicated malaria in children from Lambaréné. However, a regular monitoring of efficacy and a study of molecular markers of drug resistance to artemisinin in field isolates is essential. Trial registration ANZCTR, ACTRN12616001600437. Registered 18 November, http://www.anzctr.org.au/TrialSearch.aspx?searchTxt=ACTRN12616001600437p&isBasic=True.


Subject(s)
Amodiaquine/therapeutic use , Antimalarials/therapeutic use , Artemether, Lumefantrine Drug Combination/therapeutic use , Artemisinins/therapeutic use , Drug Monitoring/statistics & numerical data , Malaria, Falciparum/drug therapy , Child , Child, Preschool , Drug Combinations , Female , Gabon , Humans , Infant , Male , Plasmodium falciparum/drug effects , Plasmodium falciparum/isolation & purification , Protozoan Proteins/genetics
5.
J Oral Maxillofac Surg ; 69(1): 242-7, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21050637

ABSTRACT

PURPOSE: Currently, no consensus has been reached regarding which track, single- or dual-degree, better prepares a resident for oral and maxillofacial surgery (OMS) practice. It is doubtful that such a consensus will ever exist. The purpose of the present study was to explore the trends in the selection of, and competition for, single- and dual-degree residency positions, with the ultimate goal of determining which degree track is in greater demand among recent applicants. MATERIALS AND METHODS: National match statistics were obtained from the American Association of Oral and Maxillofacial Surgeons. Data were drawn from each annual residency match for 1986-1987 through 2009-2010. For each match year, the data included the total number of OMS residency applicants participating in the National Matching Service, the total number of OMS positions offered, and the number of single- and dual-degree OMS positions that had been successfully matched. A piecewise regression analysis was used to evaluate the trends in the data. RESULTS: During the 1996-1997 to 2009-2010 period, both the preference for single- and dual-degree positions and the proportion of single- and dual-degree positions offered remained relatively constant. On average, 50.19% ± 2.27% of applicants preferred single-degree positions, 24.44% ± 2.42% preferred dual-degree positions, and 25.70% ± 2.27% had no preference. The demand for each single-degree position from 1996-1997 to 2009-2010 was 1.44 times greater than that for each dual-degree position (P < .0001). CONCLUSIONS: The proportions of single- and dual-degree OMS residency positions and applicant preference for a single- or dual-degree position have remained relatively constant during the past 14 match years. Recent trends have suggested a significantly greater demand for the single- versus dual-degree OMS residency position.


Subject(s)
Education, Dental, Graduate , Education, Medical, Graduate , Internship and Residency , Surgery, Oral/education , Attitude of Health Personnel , Education, Dental, Graduate/statistics & numerical data , Education, Medical, Graduate/statistics & numerical data , Humans , Internship and Residency/statistics & numerical data , Personnel Selection/statistics & numerical data , Surgery, Oral/statistics & numerical data , United States
6.
J Infect Dis ; 193(11): 1552-6, 2006 Jun 01.
Article in English | MEDLINE | ID: mdl-16652284

ABSTRACT

Targeting viral proteins early during infection may limit exacerbation of human cytomegalovirus infection. The viral chemokine-receptor homologue US28 interferes with leukocyte trafficking and, possibly, viral replication. Because US28 molecules are abundant on the surface of infected cells, this homologue is a potential target for antiviral therapy. To assess the relationship between US28 and disease activity, we measured, by quantitative reverse-transcription polymerase chain reaction, the levels of US28 and immediate-early (IE) 1 gene transcripts in the blood of lung-transplant recipients. We found that, during primary and secondary infection, the IE1 and US28 genes have early transcription kinetics and are expressed at similar levels. This may render US28 an attractive target for antiviral therapy.


Subject(s)
Cytomegalovirus Infections/virology , Gene Expression , Lung Transplantation , Receptors, Chemokine/genetics , Viral Proteins/genetics , Adult , Antigens, Viral/blood , Humans , Immediate-Early Proteins/genetics , Kinetics , Middle Aged , Phosphoproteins/blood , RNA, Messenger/blood , RNA, Viral/blood , Reverse Transcriptase Polymerase Chain Reaction , Transcription, Genetic , Viral Matrix Proteins/blood
7.
Virus Res ; 118(1-2): 196-200, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16448715

ABSTRACT

The activation of the major immediate-early promoter (MIEP) is a key event in the cytomegalovirus replication cycle and is dependent on cellular transcription factors which are partially activated by viral proteins. Expression of the viral chemokine receptor homolog US28 results in constitutive activation of pro-inflammatory transcription factors that may be involved in the activation of the major immediate-early promoter/enhancer. Using reporter gene assays in human embryonic kidney cells, we found that US28 signaling was responsible for increased major immediate-early promoter/enhancer activity which was independent of beta-chemokine binding. Inhibition of nuclear factor-kappaB (NF-kappaB) only partially blocked the effect of US28, whereas treatment with a specific p38 mitogen activated kinase (MAPK) inhibitor fully abrogated the US28-induced enhancement of promoter activity. Our results suggest that during human cytomegalovirus (HCMV) infection, US28 in epithelial cells transactivates the major immediate-early promoter/enhancer via the activation of p38 MAPK and downstream signaling that partially involves NF-kappaB.


Subject(s)
Cytomegalovirus/physiology , Enhancer Elements, Genetic , Gene Expression Regulation, Viral , Genes, Immediate-Early , Promoter Regions, Genetic , Receptors, Chemokine/physiology , Viral Proteins/physiology , Artificial Gene Fusion , Cell Line , Cytomegalovirus/genetics , Genes, Reporter , Humans , Luciferases/genetics , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Receptors, Chemokine/genetics , Signal Transduction , Viral Proteins/genetics , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , p38 Mitogen-Activated Protein Kinases/metabolism
8.
Nephrol Dial Transplant ; 20(11): 2524-31, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16115856

ABSTRACT

BACKGROUND: C-reactive protein (CRP) is a predictor of coronary heart disease, total mortality and chronic allograft nephropathy in renal transplant recipients. The determinants of CRP have been investigated in the general population, but not in renal transplant recipients. CRP might reflect metabolic aberrations in association with central obesity and systemic atherosclerosis. However, it may also reflect a low-grade immune-mediated response to the graft. In this study we investigated the factors associated with CRP in a renal transplant population. METHODS: Between August 2001 and July 2003, renal transplant recipients with a functioning graft for more than 1 year (n = 847) were eligible for investigation at their next visit to the outpatient clinic. A total of 606 patients (55% male, aged 51+/-12 years) participated at a median (interquartile range) time of 6.0 (2.6-11.4) years post-transplant. RESULTS: Median CRP concentration was 2.0 (0.80-4.8) mg/l and mean 24 h creatinine clearance was 62+/-22 ml/min. CRP was significantly associated with body mass index, waist circumference and waist-to-hip ratio (P-value < 0.0001). None of the transplant characteristics except creatinine clearance was associated with CRP. In multiple regression analysis, waist circumference, log sICAM-1 concentration, gender, creatinine clearance and current smoking were independently associated with CRP. CONCLUSIONS: In renal transplant recipients waist circumference and smoking are the two most important modifiable independent determinants of CRP. Furthermore, CRP is independently associated with the endothelial function parameter sICAM-1 and, in univariate analyses, associated with multiple cardiovascular risk factors. CRP is not associated with any of the transplant-related factors, except for renal transplant function.


Subject(s)
C-Reactive Protein/metabolism , Cardiovascular Diseases/etiology , Graft Rejection/blood , Kidney Transplantation , Obesity/blood , Smoking/adverse effects , Adult , Biomarkers/blood , Body Mass Index , Cardiovascular Diseases/blood , Chronic Disease , Creatinine/blood , Female , Follow-Up Studies , Graft Rejection/complications , Graft Rejection/prevention & control , Humans , Immunosuppressive Agents/therapeutic use , Male , Middle Aged , Obesity/complications , Prognosis , Retrospective Studies , Risk Factors
9.
Rev Med Virol ; 15(4): 269-82, 2005.
Article in English | MEDLINE | ID: mdl-15861487

ABSTRACT

Mimicking host proteins is a strategy adopted by several herpesviruses to exploit the host cell for their own benefit. In this respect the human cytomegalovirus (HCMV) chemokine receptor homologue US28, has been extensively studied. Molecular pirates such as US28 can teach us about crucial events in HCMV infection and may either offer a potential target for antiviral therapy or provide an alternative strategy to immune suppression. Despite elaborate research into the chemokine binding affinity, signalling properties, intracellular trafficking and expression kinetics of US28, a solid hypothesis about the role of US28 in HCMV infection has not yet been proposed. It appears that US28 may behave as a molecular pirate that employs smart strategies for cell entry, host gene regulation and immune evasion. This review will elaborate on these aspects of US28 biology and discuss possible implications for HCMV infection.


Subject(s)
Cytomegalovirus Infections/physiopathology , Cytomegalovirus/physiology , Receptors, Chemokine/physiology , Viral Proteins/physiology , Arteriosclerosis/etiology , Chemokine CX3CL1 , Chemokines, CX3C/metabolism , Humans , Membrane Proteins/metabolism , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/virology , Myocytes, Smooth Muscle/physiology , Myocytes, Smooth Muscle/virology , Signal Transduction , Virus Latency
10.
Biomaterials ; 26(23): 4874-81, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15763267

ABSTRACT

The foreign body response is characterized by enhanced recruitment of inflammatory cells. As the directional movement of cells is controlled by chemokines, disruption of the chemokine network would be an attractive approach to improve biocompatibility of an implanted material. The sequestration of chemokines by cell surface-expressed glycosaminoglycans (GAGs) is vital for in vivo chemokine activity. The myxoma virus encodes a soluble protein, M-T7, that interacts with conserved GAG-binding domains of chemokines to block chemokine-mediated leukocyte recruitment. We hypothesized that M-T7 might also affect the function of other inflammation-associated proteins in addition to chemokines that bind to GAG. In our studies, we focussed on the modulation of the GAG-binding molecules macrophage chemoattractant protein-1 (MCP-1) and vascular endothelial growth factor-164 (VEGF164) in the inflammatory reaction against subcutaneously implanted degradable cross-linked dermal sheep collagen discs in AO rats. Genetic delivery of M-T7 delays the influx of macrophages into the collagen discs. In addition, angiogenesis around the implanted material was reduced. The discs revealed reduced levels of rat MCP-1 and rat VEGF164. This was not due to down regulation of transcription of the genes that encode MCP-1 and VEGF164. Our in vivo observations suggest that, in addition to chemokines such as MCP-1, M-T7 neutralizes VEGF164.


Subject(s)
Foreign-Body Reaction/immunology , Foreign-Body Reaction/prevention & control , Genetic Therapy/methods , Neovascularization, Pathologic/immunology , Neovascularization, Pathologic/prevention & control , Receptors, Interferon/immunology , Vascular Endothelial Growth Factor A/immunology , Viral Proteins/immunology , Animals , Cell Line , Foreign-Body Reaction/pathology , Immunologic Factors/genetics , Immunologic Factors/immunology , Kidney , Male , Neovascularization, Pathologic/complications , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Rabbits , Rats , Receptors, Interferon/genetics , Transfection/methods , Vascular Endothelial Growth Factor A/genetics , Viral Proteins/genetics
11.
Cytokine Growth Factor Rev ; 16(1): 91-103, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15733834

ABSTRACT

The chemokine network is an extensive system that regulates many immune functions such as leukocyte locomotion, T cell differentiation, angiogenesis and mast cell degranulation. Tight control of chemokines is vital for proper immune function. Not surprisingly, viruses have found ways to subvert or exploit the immune system in order to persist in co-existence with their hosts. Several viral immune evasion genes encode proteins that modulate the chemokine network. We attempt to identify which aspects of the chemokine control mechanisms are susceptible to modulation. Chemokine-glycosaminoglycan interaction, extracellular processing of chemokines and chemokine scavenging will be discussed in the light of poxvirus and herpesvirus immune evasion. Viral chemokine-modulatory proteins may either be targets for anti-viral therapy or lead the way to new anti-inflammatory chemokine-modulating drugs.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Antiviral Agents/therapeutic use , Chemokines/physiology , Viral Proteins/antagonists & inhibitors , Viral Proteins/therapeutic use , Anti-Inflammatory Agents/pharmacology , Antiviral Agents/pharmacology , Chemokines/antagonists & inhibitors , Herpesviridae/pathogenicity , Poxviridae/pathogenicity
12.
Transpl Infect Dis ; 6(1): 15-22, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15225222

ABSTRACT

UNLABELLED: Post-transplant lymphoproliferative disease (PTLD) is one of the major causes of morbidity and mortality in transplantation patients. A primary Epstein-Barr virus (EBV) infection is a major risk factor for developing PTLD. The aim of this study was to determine circulating EBV DNA after liver transplantation in pediatric patients in relation to primary EBV infection and development of PTLD. EBV serology was performed before transplantation. Every 4 weeks after transplantation a competitive quantitative polymerase chain reaction (PCR) assay for EBV nuclear antigen-1 was performed in 13 patients. Patients were followed for development of a PTLD. Before transplantation four patients were EBV seropositive and nine patients were EBV seronegative. In one of the four patients who were EBV seropositive before transplantation, EBV DNA became detectable after transplantation, with a peak load of 3600 copies/mL. None of these four patients developed a PTLD. Eight of the nine patients who were EBV seronegative before transplantation developed positive EBV DNA samples. EBV DNA was first detected at a mean of 64 days after transplantation (range 38-89). The mean peak EBV DNA load was 79,700 copies/mL (3600-446,000). Two of these patients developed PTLD, but they could not be identified based on prior or concomitant EBV PCR results. CONCLUSIONS: In pediatric liver transplantation EBV DNA load is higher in patients with a primary infection than in patients who were EBV seropositive before transplantation. The EBV PCR cannot be used to identify individual patients who develop PTLD. However, elevated EBV DNA load can be used to detect a group of patients at increased risk for PTLD.


Subject(s)
DNA, Viral/blood , Herpesvirus 4, Human/isolation & purification , Liver Transplantation/adverse effects , Lymphoproliferative Disorders , Viral Load , Adolescent , Child , Child, Preschool , Epstein-Barr Virus Infections/diagnosis , Epstein-Barr Virus Infections/virology , Humans , Infant , Lymphoproliferative Disorders/diagnosis , Lymphoproliferative Disorders/prevention & control , Lymphoproliferative Disorders/virology , Polymerase Chain Reaction , Prospective Studies
13.
Transpl Infect Dis ; 5(3): 112-20, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14617298

ABSTRACT

Although cytomegalovirus (CMV) pulmonary involvement after solid organ transplantation is infrequently seen nowadays, CMV pneumonitis is still a potential lethal complication. Introduction of the pp65 antigenemia assay enabled early and rapid diagnosis of CMV viremia in transplant patients prior to symptoms. Also, in asymptomatic patients with CMV viremia, a decreased pulmonary diffusion capacity could be demonstrated. In this review, we discuss clinical and subclinical pulmonary involvement of CMV infection in the immunocompromised host with an emphasis on transplant recipients. The clinical course, diagnosis, therapy, prophylaxis, and pathophysiology of CMV pneumonitis are discussed.


Subject(s)
Cytomegalovirus Infections , Immunocompromised Host , Organ Transplantation/adverse effects , Pneumonia, Viral , Animals , Antiviral Agents/therapeutic use , Cytomegalovirus/isolation & purification , Cytomegalovirus Infections/diagnosis , Cytomegalovirus Infections/drug therapy , Cytomegalovirus Infections/physiopathology , Cytomegalovirus Infections/virology , Humans , Mice , Pneumonia, Viral/diagnosis , Pneumonia, Viral/drug therapy , Pneumonia, Viral/physiopathology , Pneumonia, Viral/virology
14.
J Virol ; 77(20): 11274-8, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14512575

ABSTRACT

The role of leukocytes in the in vivo dissemination of cytomegalovirus was studied in this experiment. Rat cytomegalovirus (RCMV) could be transferred to rat granulocytes and monocytes by cocultivation with RCMV-infected fibroblasts in vitro. Intravenous injection of purified infected granulocytes or monocytes resulted in a systemic infection in rats, indicating that our model is a powerful tool to gain further insight into CMV dissemination and the development of new antivirals.


Subject(s)
Granulocytes/virology , Monocytes/virology , Muromegalovirus/physiology , Animals , DNA, Viral/blood , Male , Neutrophils/virology , Rats
15.
Am J Kidney Dis ; 41(4): 859-67, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12666073

ABSTRACT

Transplantation is the preferred organ replacement therapy for most patients with end-stage renal disease. Despite impressive improvements over recent years in the treatment of acute rejection, approximately half of all grafts will loose function within 10 years after transplantation. Chronic renal transplant dysfunction, also known as transplant atherosclerosis, is a leading cause of late allograft loss. To date, no specific treatment for chronic renal transplant dysfunction is available. Although its precise pathophysiology remains unknown, it is believed that it involves a multifactorial process of alloantigen-dependent and alloantigen-independent risk factors. Obesity, posttransplant diabetes mellitus, dyslipidemia, hypertension, and proteinuria have all been identified as alloantigen-independent risk factors. Notably, these recipient-related risk factors are well-known risk factors for cardiovascular disease, which cluster within the insulin resistance syndrome in the general population. Insulin resistance is considered the central pathophysiologic feature of this syndrome. It is therefore tempting to speculate that it is insulin resistance that underlies the recipient-related risk factors for chronic renal transplant dysfunction. Recognition of insulin resistance as a central feature underlying many, if not all, recipient-related risk factors would not only improve our understanding of the pathophysiology of chronic renal transplant dysfunction, but also stimulate development of new treatment and prevention strategies.


Subject(s)
Graft Survival/physiology , Insulin Resistance , Kidney Transplantation , Kidney/physiopathology , Metabolic Syndrome/complications , Postoperative Complications/etiology , Arteriosclerosis/epidemiology , Diabetes Mellitus/epidemiology , Diet/adverse effects , Forecasting , Humans , Hyperlipidemias/epidemiology , Hypertension/epidemiology , Kidney Failure, Chronic/diet therapy , Kidney Failure, Chronic/epidemiology , Kidney Failure, Chronic/surgery , Kidney Failure, Chronic/therapy , Metabolic Syndrome/epidemiology , Obesity/epidemiology , Postoperative Complications/epidemiology , Proteinuria/epidemiology , Renal Dialysis , Risk Factors
16.
J Med Virol ; 69(2): 258-66, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12683416

ABSTRACT

The Epstein-Barr virus (EBV)-specific antibody response was studied in lung transplant patients to assess their value in the diagnosis and prognosis of post-transplant lymphoproliferative disease. Recently developed synthetic peptides representing Epstein-Barr nuclear antigen-1 (EBNA-1), diffuse early antigen (EA(D)), and virus capsid antigen (VCA) were studied in a semiquantitative enzyme-linked immunosorbent assay (ELISA) to study antibody patterns in 12 seronegative lung transplant patients, of whom four developed a post-transplant lymphoproliferative disease, and seven seropositive lung transplant patients, all of whom developed a post-transplant lymphoproliferative disease. Immunoblot technique was used as a control. All 12 EBV-seronegative patients had a very limited antibody response that was restricted mainly to VCA antibodies. EA(D) antibodies became detectable in only two patients. Antibody response never preceded clinical diagnosis of post-transplant lymphoproliferative disease in the four EBV-seronegative patients who developed post-transplant lymphoproliferative disease. In the seven seropositive lung transplant patients with post-transplant lymphoproliferative disease, we found a rise in antibody titer in only two patients. Immunoblot analysis confirmed the serological results. In conclusion, EBV-specific antibody patterns after lung transplantation are highly restricted and variable and of limited value for the diagnosis or prognosis of post-transplant lymphoproliferative disease.


Subject(s)
Antibodies, Viral/blood , Epstein-Barr Virus Infections/immunology , Herpesvirus 4, Human/immunology , Lung Transplantation/adverse effects , Lymphoproliferative Disorders/immunology , Adolescent , Adult , Child , Epstein-Barr Virus Infections/virology , Female , Humans , Immunoblotting , Lung Transplantation/immunology , Lymphoproliferative Disorders/diagnosis , Lymphoproliferative Disorders/virology , Male , Middle Aged
17.
Transplantation ; 74(9): 1320-7, 2002 Nov 15.
Article in English | MEDLINE | ID: mdl-12451273

ABSTRACT

BACKGROUND: In solid-organ transplantation, the allograft vasculature, in particular the endothelium, is prone to injury inflicted by peritransplantational and posttransplantational factors. Previously, we have shown that circulating endothelial cells (cEC) can be detected in the peripheral blood of kidney allograft recipients and are often associated with acute rejection and active infections with human cytomegalovirus. In the present study we hypothesized that cEC after kidney transplantation are of donor origin, thus reflecting transplantation-related damage to the allograft endothelium. METHODS: Using hydraulic micromanipulation equipment, we isolated single cEC (n=153) from the peripheral blood of nine kidney allograft recipients at various time points after transplantation. We demonstrated the origin of these cells (donor or recipient) by typing their HLA-DRB alleles by single-cell, genomic, nested polymerase chain reaction. RESULTS: The majority (71.8%) of cEC were of donor origin and could be detected up to 141 days after onset of acute rejection episodes. Although less frequent (28.2%), recipient-type cEC were detected in the same time course as donor-type cEC. CONCLUSION: We conclude that posttransplantational injury to the allograft endothelium is reflected by the presence of donor-derived cEC in the blood.


Subject(s)
Blood Cells/pathology , Endothelium, Vascular/pathology , Kidney Transplantation , Acute Disease , Adult , Blood Cells/physiology , Cell Line , Cytomegalovirus Infections/pathology , Endothelium, Vascular/physiopathology , Female , Graft Rejection/pathology , Humans , Male , Middle Aged , Phenotype , Postoperative Period , Tissue Donors
18.
Protein Expr Purif ; 25(3): 400-8, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12182819

ABSTRACT

Herpes simplex virus type 1 and 2 (HSV-1 and -2) glycoproteins D (gD-1 and gD-2) play a role in the entry of the virus into the host cell. Availability of substantial amounts of these proteins, or large fragments thereof, will be needed to allow studies at the molecular level. We studied the potency of the Pichia pastoris yeast expression system to produce soluble forms of gD. The DNA sequences encoding the extracellular domains of gD [amino acids 1-314 (gD-1(1-314)) and amino acids 1-254 (gD-1(1-254)) of gD-1 and amino acids 1-314 of gD-2 (gD-2(1-314))] were cloned into the P. pastoris yeast expression vector pPIC9. Two truncated forms of gD-1 were fitted with a His tail (designated as gD-1(1-314His) and gD-1(1-254His)) to facilitate their purification. Large amounts of gD-1(1-314) and gD-1(1-314His) (280-300mg/L induction medium) were produced. The yields of recombinant gD-1(1-254) and gD-1(1-254His) were lower: 20-36mg/L, and the yield of the gD-2(1-314) fragment was much lower: 6mg/L. SDS-PAGE analysis revealed multiple glycosylated species of the larger gD fragments, ranging in apparent molecular weight from 31 to 78kDa. The smaller gD-1(1-254) fragment appeared as two bands with molecular weights of 33 and 31kDa. All recombinant proteins produced by P. pastoris were recognized, as expected, by a panel of MAbs (A16, DL6, A18, DL11, HD1, ABDI, and AP7). In addition, we showed that gD-1(1-314), gD-2(1-314), and gD-1(1-254His) were able to interfere with binding of HSV to susceptible cells. These results indicate that the conformations of the recombinant proteins closely resemble those of native gD.


Subject(s)
Herpesvirus 1, Human/genetics , Herpesvirus 2, Human/genetics , Peptide Fragments/genetics , Peptide Fragments/metabolism , Pichia/genetics , Viral Envelope Proteins/genetics , Viral Envelope Proteins/metabolism , Chromatography, High Pressure Liquid , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Gene Expression , Genetic Vectors , Herpesvirus 1, Human/chemistry , Herpesvirus 2, Human/chemistry , Peptide Fragments/biosynthesis , Peptide Fragments/isolation & purification , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Solubility , Viral Envelope Proteins/biosynthesis , Viral Envelope Proteins/isolation & purification
19.
Scand J Immunol ; 56(3): 254-9, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12193226

ABSTRACT

We investigated if dendritic cells (DCs) were able to present intracellularly located antigens derived from apoptotic cells to T cells, thereby inducing a CD4+ and a CD8+ response. A transfected cell line with the cytomegalovirus-derived protein pp65 was triggered to go into apoptosis by ultraviolet B (UVB) irradiation, and after the uptake of apoptotic cells by DC, the activation and proliferation of T cells were determined. We found that DC efficiently phagocytosed apoptotic cells and induced a CD4+ and a CD8+ T-cell response specific for the viral protein pp65. This mechanism can be useful for vaccination studies to induce an antiviral immune response.


Subject(s)
Antigen Presentation , Antigens, Viral/immunology , Apoptosis , Dendritic Cells/immunology , Lymphocyte Activation , T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/immunology , Cells, Cultured , Cytoplasm/virology , Humans , Jurkat Cells , Phagocytosis , Phosphoproteins/immunology , T-Lymphocytes, Cytotoxic/immunology , Viral Matrix Proteins/immunology
20.
Transpl Infect Dis ; 4(1): 17-24, 2002 Mar.
Article in English | MEDLINE | ID: mdl-12123422

ABSTRACT

Background. In this retrospective single center study we have evaluated the relation between the immunosuppressive regimen and the incidence and characteristics of cytomegalovirus (CMV) infection in the setting without CMV prophylaxis from 1989 through 1998. Methods. All (470) first cadaveric renal transplantations in nonsensitized (PRA < 60%) patients were analyzed. Immunosuppression consisted of cyclosporine A (Sandimmune) and prednisolone from 1989 through 2-1993 (S; 189 patients), of cyclosporine microemulsion (Neoral) and prednisolone from 3-1993 through 5-1997 (N; 200 patients) and of mycophenolate mofetil, Neoral and prednisolone from 5-1997 until 1998 (M; 81 patients). The CMV pp65-antigenemia was measured routinely at least once weekly from day 10 till 12 weeks after transplantation or until pp65-antigenemia became negative. No CMV-prophylaxis was given. Results. By changing from Sandimmune to Neoral and by adding mycophenolate mofetil, respectively, we observed a higher frequency of especially secondary CMV infections (S vs. N vs. M, respectively, 28 vs. 50 vs. 63%, P = 0.026; S vs. N, P = 0.027; S vs. M, P = 0.015; and N vs. M, n.s). The CMV infections lasted longer (median duration antigenemia S vs. N vs. M, respectively, 3 vs. 5 vs. 7 weeks, P = 0.0003; S vs. N, P < 0.002; S vs. M, P < 0.001; and N vs. M, P < 0.05). Viral load was higher in M (median maximal pp65-antigenemia S vs. N vs. M, respectively, 19 vs. 14.5 vs. 73, P < 0.01; S vs. N, n.s.; S vs. M, P < 0.001 and N vs. M, P < 0.01). Conclusions. The use of Neoral and the addition of mycophenolate mofetil caused significant changes in the incidence, duration and viral load of CMV infections.


Subject(s)
Cytomegalovirus Infections/virology , Cytomegalovirus/isolation & purification , Immunosuppressive Agents/adverse effects , Kidney Transplantation , Mycophenolic Acid/analogs & derivatives , Postoperative Complications , Cyclosporine/adverse effects , Cytomegalovirus/immunology , Cytomegalovirus Infections/blood , Cytomegalovirus Infections/epidemiology , Drug Therapy, Combination , Female , Graft Rejection/prevention & control , Humans , Male , Middle Aged , Mycophenolic Acid/adverse effects , Phosphoproteins/blood , Prednisolone/adverse effects , Retrospective Studies , Viral Load , Viral Matrix Proteins/blood , Viremia
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